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* [PATCH 01/11] uapi: General notification ring definitions [ver #7]
From: David Howells @ 2019-08-30 13:57 UTC (permalink / raw)
  To: viro
  Cc: dhowells, Casey Schaufler, Stephen Smalley, Greg Kroah-Hartman,
	nicolas.dichtel, raven, Christian Brauner, dhowells, keyrings,
	linux-usb, linux-security-module, linux-fsdevel, linux-api,
	linux-block, linux-security-module, linux-kernel
In-Reply-To: <156717343223.2204.15875738850129174524.stgit@warthog.procyon.org.uk>

Add UAPI definitions for the general notification ring, including the
following pieces:

 (1) struct watch_notification.

     This is the metadata header for each entry in the ring.  It includes a
     type and subtype that indicate the source of the message
     (eg. WATCH_TYPE_MOUNT_NOTIFY) and the kind of the message
     (eg. NOTIFY_MOUNT_NEW_MOUNT).

     The header also contains an information field that conveys the
     following information:

	- WATCH_INFO_LENGTH.  The size of the entry (entries are variable
          length).

	- WATCH_INFO_ID.  The watch ID specified when the watchpoint was
          set.

	- WATCH_INFO_TYPE_INFO.  (Sub)type-specific information.

	- WATCH_INFO_FLAG_*.  Flag bits overlain on the type-specific
          information.  For use by the type.

     All the information in the header can be used in filtering messages at
     the point of writing into the buffer.

 (2) struct watch_queue_buffer.

     This describes the layout of the ring.  Note that the first slots in
     the ring contain a special metadata entry that contains the ring
     pointers.  The producer in the kernel knows to skip this and it has a
     proper header (WATCH_TYPE_META, WATCH_META_SKIP_NOTIFICATION) that
     indicates the size so that the ring consumer can handle it the same as
     any other record and just skip it.

     Note that this means that ring entries can never be split over the end
     of the ring, so if an entry would need to be split, a skip record is
     inserted to wrap the ring first; this is also WATCH_TYPE_META,
     WATCH_META_SKIP_NOTIFICATION.

 (3) WATCH_INFO_NOTIFICATIONS_LOST.

     This is a flag that can be set in the metadata header by the kernel to
     indicate that at least one message was lost since it was last cleared
     by userspace.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

 include/uapi/linux/watch_queue.h |   67 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 67 insertions(+)
 create mode 100644 include/uapi/linux/watch_queue.h

diff --git a/include/uapi/linux/watch_queue.h b/include/uapi/linux/watch_queue.h
new file mode 100644
index 000000000000..70f575099968
--- /dev/null
+++ b/include/uapi/linux/watch_queue.h
@@ -0,0 +1,67 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _UAPI_LINUX_WATCH_QUEUE_H
+#define _UAPI_LINUX_WATCH_QUEUE_H
+
+#include <linux/types.h>
+
+enum watch_notification_type {
+	WATCH_TYPE_META		= 0,	/* Special record */
+	WATCH_TYPE___NR		= 1
+};
+
+enum watch_meta_notification_subtype {
+	WATCH_META_SKIP_NOTIFICATION	= 0,	/* Just skip this record */
+	WATCH_META_REMOVAL_NOTIFICATION	= 1,	/* Watched object was removed */
+};
+
+#define WATCH_LENGTH_GRANULARITY sizeof(__u64)
+
+/*
+ * Notification record header.  This is aligned to 64-bits so that subclasses
+ * can contain __u64 fields.
+ */
+struct watch_notification {
+	__u32			type:24;	/* enum watch_notification_type */
+	__u32			subtype:8;	/* Type-specific subtype (filterable) */
+	__u32			info;
+#define WATCH_INFO_LENGTH	0x0000003f	/* Length of record / sizeof(watch_notification) */
+#define WATCH_INFO_LENGTH__SHIFT 0
+#define WATCH_INFO_ID		0x0000ff00	/* ID of watchpoint, if type-appropriate */
+#define WATCH_INFO_ID__SHIFT	8
+#define WATCH_INFO_TYPE_INFO	0xffff0000	/* Type-specific info */
+#define WATCH_INFO_TYPE_INFO__SHIFT 16
+#define WATCH_INFO_FLAG_0	0x00010000	/* Type-specific info, flag bit 0 */
+#define WATCH_INFO_FLAG_1	0x00020000	/* ... */
+#define WATCH_INFO_FLAG_2	0x00040000
+#define WATCH_INFO_FLAG_3	0x00080000
+#define WATCH_INFO_FLAG_4	0x00100000
+#define WATCH_INFO_FLAG_5	0x00200000
+#define WATCH_INFO_FLAG_6	0x00400000
+#define WATCH_INFO_FLAG_7	0x00800000
+} __attribute__((aligned(WATCH_LENGTH_GRANULARITY)));
+
+struct watch_queue_buffer {
+	union {
+		/* The first few entries are special, containing the
+		 * ring management variables.
+		 */
+		struct {
+			struct watch_notification watch; /* WATCH_TYPE_META */
+			__u32		head;		/* Ring head index */
+			__u32		tail;		/* Ring tail index */
+			__u32		mask;		/* Ring index mask */
+			__u32		__reserved;
+		} meta;
+		struct watch_notification slots[0];
+	};
+};
+
+/*
+ * The Metadata pseudo-notification message uses a flag bits in the information
+ * field to convey the fact that messages have been lost.  We can only use a
+ * single bit in this manner per word as some arches that support SMP
+ * (eg. parisc) have no kernel<->user atomic bit ops.
+ */
+#define WATCH_INFO_NOTIFICATIONS_LOST WATCH_INFO_FLAG_0
+
+#endif /* _UAPI_LINUX_WATCH_QUEUE_H */


^ permalink raw reply related

* [PATCH 00/11] Keyrings, Block and USB notifications [ver #7]
From: David Howells @ 2019-08-30 13:57 UTC (permalink / raw)
  To: viro
  Cc: dhowells, Casey Schaufler, Stephen Smalley, Greg Kroah-Hartman,
	nicolas.dichtel, raven, Christian Brauner, dhowells, keyrings,
	linux-usb, linux-security-module, linux-fsdevel, linux-api,
	linux-block, linux-security-module, linux-kernel


Here's a set of patches to add a general notification queue concept and to
add sources of events for:

 (1) Key/keyring events, such as creating, linking and removal of keys.

 (2) General device events (single common queue) including:

     - Block layer events, such as device errors

     - USB subsystem events, such as device/bus attach/remove, device
       reset, device errors.

Tests for the key/keyring events can be found on the keyutils next branch:

	https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/log/?h=next

Notifications are done automatically inside of the testing infrastructure
on every change to that every test makes to a key or keyring.

Manual pages can be found there also, including pages for watch_queue(7)
and the watch_devices(2) system call (these should be transferred to the
manpages package if taken upstream).

LSM hooks are included:

 (1) A set of hooks are provided that allow an LSM to rule on whether or
     not a watch may be set.  Each of these hooks takes a different
     "watched object" parameter, so they're not really shareable.  The LSM
     should use current's credentials.  [Wanted by SELinux & Smack]

 (2) A hook is provided to allow an LSM to rule on whether or not a
     particular message may be posted to a particular queue.  This is given
     the credentials from the event generator (which may be the system) and
     the watch setter.  [Wanted by Smack]

I've provided a preliminary attempt to provide SELinux and Smack with
implementations of some of these hooks.


Design decisions:

 (1) A misc chardev is used to create and open a ring buffer:

	fd = open("/dev/watch_queue", O_RDWR);

     which is then configured and mmap'd into userspace:

	ioctl(fd, IOC_WATCH_QUEUE_SET_SIZE, BUF_SIZE);
	ioctl(fd, IOC_WATCH_QUEUE_SET_FILTER, &filter);
	buf = mmap(NULL, BUF_SIZE * page_size, PROT_READ | PROT_WRITE,
		   MAP_SHARED, fd, 0);

     The fd cannot be read or written (though there is a facility to use
     write to inject records for debugging) and userspace just pulls data
     directly out of the buffer.

 (2) The ring index pointers are stored inside the ring and are thus
     accessible to userspace.  Userspace should only update the tail
     pointer and never the head pointer or risk breaking the buffer.  The
     kernel checks that the pointers appear valid before trying to use
     them.  A 'skip' record is maintained around the pointers.

 (3) poll() can be used to wait for data to appear in the buffer.

 (4) Records in the buffer are binary, typed and have a length so that they
     can be of varying size.

     This means that multiple heterogeneous sources can share a common
     buffer.  Tags may be specified when a watchpoint is created to help
     distinguish the sources.

 (5) The queue is reusable as there are 16 million types available, of
     which I've used just a few, so there is scope for others to be used.

 (6) Records are filterable as types have up to 256 subtypes that can be
     individually filtered.  Other filtration is also available.

 (7) Each time the buffer is opened, a new buffer is created - this means
     that there's no interference between watchers.

 (8) When recording a notification, the kernel will not sleep, but will
     rather mark a queue as overrun if there's insufficient space, thereby
     avoiding userspace causing the kernel to hang.

 (9) The 'watchpoint' should be specific where possible, meaning that you
     specify the object that you want to watch.

(10) The buffer is created and then watchpoints are attached to it, using
     one of:

	keyctl_watch_key(KEY_SPEC_SESSION_KEYRING, fd, 0x01);
	watch_devices(fd, 0x02, 0);

     where in both cases, fd indicates the queue and the number after is a
     tag between 0 and 255.

(11) The watch must be removed if either the watch buffer is destroyed or
     the watched object is destroyed.


Things I want to avoid:

 (1) Introducing features that make the core VFS dependent on the network
     stack or networking namespaces (ie. usage of netlink).

 (2) Dumping all this stuff into dmesg and having a daemon that sits there
     parsing the output and distributing it as this then puts the
     responsibility for security into userspace and makes handling
     namespaces tricky.  Further, dmesg might not exist or might be
     inaccessible inside a container.

 (3) Letting users see events they shouldn't be able to see.


The patches can be found here also:

	http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=notifications-core

Changes:

 ver #7:

 (*) Removed the 'watch' argument from the security_watch_key() and
     security_watch_devices() hooks as current_cred() can be used instead
     of watch->cred.

 ver #6:

 (*) Fix mmap bug in watch_queue driver.

 (*) Add an extended removal notification that can transmit an identifier
     to userspace (such as a key ID).

 (*) Don't produce a instantiation notification in mark_key_instantiated()
     but rather do it in the caller to prevent key updates from producing
     an instantiate notification as well as an update notification.

 (*) Set the right number of filters in the sample program.

 (*) Provide preliminary hook implementations for SELinux and Smack.

 ver #5:

 (*) Split the superblock watch and mount watch parts out into their own
     branch (notifications-mount) as they really need certain fsinfo()
     attributes.

 (*) Rearrange the watch notification UAPI header to push the length down
     to bits 0-5 and remove the lost-message bits.  The userspace's watch
     ID tag is moved to bits 8-15 and then the message type is allocated
     all of bits 16-31 for its own purposes.

     The lost-message bit is moved over to the header, rather than being
     placed in the next message to be generated and given its own word so
     it can be cleared with xchg(,0) for parisc.

 (*) The security_post_notification() hook is no longer called with the
     spinlock held and softirqs disabled - though the RCU readlock is still
     held.

 (*) Buffer pages are now accounted towards RLIMIT_MEMLOCK and CAP_IPC_LOCK
     will skip the overuse check.

 (*) The buffer is marked VM_DONTEXPAND.

 (*) Save the watch-setter's creds in struct watch and give that to the LSM
     hook for posting a message.

 ver #4:

 (*) Split the basic UAPI bits out into their own patch and then split the
     LSM hooks out into an intermediate patch.  Add LSM hooks for setting
     watches.

     Rename the *_notify() system calls to watch_*() for consistency.

 ver #3:

 (*) I've added a USB notification source and reformulated the block
     notification source so that there's now a common watch list, for which
     the system call is now device_notify().

     I've assigned a pair of unused ioctl numbers in the 'W' series to the
     ioctls added by this series.

     I've also added a description of the kernel API to the documentation.

 ver #2:

 (*) I've fixed various issues raised by Jann Horn and GregKH and moved to
     krefs for refcounting.  I've added some security features to try and
     give Casey Schaufler the LSM control he wants.

David
---
David Howells (11):
      uapi: General notification ring definitions
      security: Add hooks to rule on setting a watch
      security: Add a hook for the point of notification insertion
      General notification queue with user mmap()'able ring buffer
      keys: Add a notification facility
      Add a general, global device notification watch list
      block: Add block layer notifications
      usb: Add USB subsystem notifications
      Add sample notification program
      selinux: Implement the watch_key security hook
      smack: Implement the watch_key and post_notification hooks [untested]


 Documentation/ioctl/ioctl-number.rst        |    1 
 Documentation/security/keys/core.rst        |   58 ++
 Documentation/watch_queue.rst               |  460 ++++++++++++++
 arch/alpha/kernel/syscalls/syscall.tbl      |    1 
 arch/arm/tools/syscall.tbl                  |    1 
 arch/ia64/kernel/syscalls/syscall.tbl       |    1 
 arch/m68k/kernel/syscalls/syscall.tbl       |    1 
 arch/microblaze/kernel/syscalls/syscall.tbl |    1 
 arch/mips/kernel/syscalls/syscall_n32.tbl   |    1 
 arch/mips/kernel/syscalls/syscall_n64.tbl   |    1 
 arch/mips/kernel/syscalls/syscall_o32.tbl   |    1 
 arch/parisc/kernel/syscalls/syscall.tbl     |    1 
 arch/powerpc/kernel/syscalls/syscall.tbl    |    1 
 arch/s390/kernel/syscalls/syscall.tbl       |    1 
 arch/sh/kernel/syscalls/syscall.tbl         |    1 
 arch/sparc/kernel/syscalls/syscall.tbl      |    1 
 arch/x86/entry/syscalls/syscall_32.tbl      |    1 
 arch/x86/entry/syscalls/syscall_64.tbl      |    1 
 arch/xtensa/kernel/syscalls/syscall.tbl     |    1 
 block/Kconfig                               |    9 
 block/blk-core.c                            |   29 +
 drivers/base/Kconfig                        |    9 
 drivers/base/Makefile                       |    1 
 drivers/base/watch.c                        |   90 +++
 drivers/misc/Kconfig                        |   13 
 drivers/misc/Makefile                       |    1 
 drivers/misc/watch_queue.c                  |  893 +++++++++++++++++++++++++++
 drivers/usb/core/Kconfig                    |    9 
 drivers/usb/core/devio.c                    |   56 ++
 drivers/usb/core/hub.c                      |    4 
 include/linux/blkdev.h                      |   15 
 include/linux/device.h                      |    7 
 include/linux/key.h                         |    3 
 include/linux/lsm_audit.h                   |    1 
 include/linux/lsm_hooks.h                   |   38 +
 include/linux/security.h                    |   32 +
 include/linux/syscalls.h                    |    1 
 include/linux/usb.h                         |   18 +
 include/linux/watch_queue.h                 |   94 +++
 include/uapi/asm-generic/unistd.h           |    4 
 include/uapi/linux/keyctl.h                 |    2 
 include/uapi/linux/watch_queue.h            |  183 ++++++
 kernel/sys_ni.c                             |    1 
 samples/Kconfig                             |    6 
 samples/Makefile                            |    1 
 samples/watch_queue/Makefile                |    8 
 samples/watch_queue/watch_test.c            |  233 +++++++
 security/keys/Kconfig                       |    9 
 security/keys/compat.c                      |    3 
 security/keys/gc.c                          |    5 
 security/keys/internal.h                    |   30 +
 security/keys/key.c                         |   38 +
 security/keys/keyctl.c                      |   99 +++
 security/keys/keyring.c                     |   20 -
 security/keys/request_key.c                 |    4 
 security/security.c                         |   23 +
 security/selinux/hooks.c                    |   14 
 security/smack/smack_lsm.c                  |   82 ++
 58 files changed, 2593 insertions(+), 30 deletions(-)
 create mode 100644 Documentation/watch_queue.rst
 create mode 100644 drivers/base/watch.c
 create mode 100644 drivers/misc/watch_queue.c
 create mode 100644 include/linux/watch_queue.h
 create mode 100644 include/uapi/linux/watch_queue.h
 create mode 100644 samples/watch_queue/Makefile
 create mode 100644 samples/watch_queue/watch_test.c


^ permalink raw reply

* Re: [RFC PATCH] audit, security: allow LSMs to selectively enable audit collection
From: Stephen Smalley @ 2019-08-30 13:44 UTC (permalink / raw)
  To: Aaron Goidel, paul
  Cc: jmorris, serge, keescook, casey, rgb, linux-audit,
	linux-security-module, selinux
In-Reply-To: <20190815174111.6309-1-acgoide@tycho.nsa.gov>

On 8/15/19 1:41 PM, Aaron Goidel wrote:
> Presently, there is no way for LSMs to enable collection of supplemental
> audit records such as path and inode information when a permission denial
> occurs. Provide a LSM hook to allow LSMs to selectively enable collection
> on a per-task basis, even if the audit configuration would otherwise
> disable auditing of a task and/or contains no audit filter rules. If the
> hook returns a non-zero result, collect all available audit information. If
> the hook generates its own audit record, then supplemental audit
> information will be emitted at syscall exit.
> 
> In SELinux, we implement this hook by returning the result of a permission
> check on the process. If the new process2:audit_enable permission is
> allowed by the policy, then audit collection will be enabled for that
> process. Otherwise, SELinux will defer to the audit configuration.

Any feedback on this RFC patch?  I know Paul provided some thoughts on 
the general topic of LSM/audit enablement in the other patch thread but 
I haven't seen any response to this patch.

> 
> Signed-off-by: Aaron Goidel <acgoide@tycho.nsa.gov>
> ---
>   include/linux/lsm_hooks.h           |  7 +++++++
>   include/linux/security.h            |  7 ++++++-
>   kernel/auditsc.c                    | 10 +++++++---
>   security/security.c                 |  5 +++++
>   security/selinux/hooks.c            | 11 +++++++++++
>   security/selinux/include/classmap.h |  2 +-
>   6 files changed, 37 insertions(+), 5 deletions(-)
> 
> diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
> index ead98af9c602..7d70a6759621 100644
> --- a/include/linux/lsm_hooks.h
> +++ b/include/linux/lsm_hooks.h
> @@ -1380,6 +1380,11 @@
>    *	audit_rule_init.
>    *	@lsmrule contains the allocated rule
>    *
> + * @audit_enable:
> + *	Allow the security module to selectively enable audit collection
> + *	on permission denials based on whether or not @tsk has the
> + *	process2:audit_enable permission.
> + *
>    * @inode_invalidate_secctx:
>    *	Notify the security module that it must revalidate the security context
>    *	of an inode.
> @@ -1800,6 +1805,7 @@ union security_list_options {
>   	int (*audit_rule_known)(struct audit_krule *krule);
>   	int (*audit_rule_match)(u32 secid, u32 field, u32 op, void *lsmrule);
>   	void (*audit_rule_free)(void *lsmrule);
> +	int (*audit_enable)(struct task_struct *tsk);
>   #endif /* CONFIG_AUDIT */
>   
>   #ifdef CONFIG_BPF_SYSCALL
> @@ -2043,6 +2049,7 @@ struct security_hook_heads {
>   	struct hlist_head audit_rule_known;
>   	struct hlist_head audit_rule_match;
>   	struct hlist_head audit_rule_free;
> +	struct hlist_head audit_enable;
>   #endif /* CONFIG_AUDIT */
>   #ifdef CONFIG_BPF_SYSCALL
>   	struct hlist_head bpf;
> diff --git a/include/linux/security.h b/include/linux/security.h
> index 7d9c1da1f659..7be66db8de4e 100644
> --- a/include/linux/security.h
> +++ b/include/linux/security.h
> @@ -1719,7 +1719,7 @@ int security_audit_rule_init(u32 field, u32 op, char *rulestr, void **lsmrule);
>   int security_audit_rule_known(struct audit_krule *krule);
>   int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule);
>   void security_audit_rule_free(void *lsmrule);
> -
> +int security_audit_enable(struct task_struct *tsk);
>   #else
>   
>   static inline int security_audit_rule_init(u32 field, u32 op, char *rulestr,
> @@ -1742,6 +1742,11 @@ static inline int security_audit_rule_match(u32 secid, u32 field, u32 op,
>   static inline void security_audit_rule_free(void *lsmrule)
>   { }
>   
> +static inline int security_audit_enable(struct task_struct *tsk)
> +{
> +	return 0;
> +}
> +
>   #endif /* CONFIG_SECURITY */
>   #endif /* CONFIG_AUDIT */
>   
> diff --git a/kernel/auditsc.c b/kernel/auditsc.c
> index 95ae27edd417..7e052b71bc42 100644
> --- a/kernel/auditsc.c
> +++ b/kernel/auditsc.c
> @@ -906,8 +906,12 @@ int audit_alloc(struct task_struct *tsk)
>   
>   	state = audit_filter_task(tsk, &key);
>   	if (state == AUDIT_DISABLED) {
> -		clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
> -		return 0;
> +		if (security_audit_enable(tsk)) {
> +			state = AUDIT_BUILD_CONTEXT;
> +		} else {
> +			clear_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
> +			return 0;
> +		}
>   	}
>   
>   	if (!(context = audit_alloc_context(state))) {
> @@ -1623,7 +1627,7 @@ void __audit_syscall_entry(int major, unsigned long a1, unsigned long a2,
>   	if (state == AUDIT_DISABLED)
>   		return;
>   
> -	context->dummy = !audit_n_rules;
> +	context->dummy = !audit_n_rules && !security_audit_enable(current);
>   	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
>   		context->prio = 0;
>   		if (auditd_test_task(current))
> diff --git a/security/security.c b/security/security.c
> index 30687e1366b7..04e160e5d4ab 100644
> --- a/security/security.c
> +++ b/security/security.c
> @@ -2333,6 +2333,11 @@ int security_audit_rule_match(u32 secid, u32 field, u32 op, void *lsmrule)
>   {
>   	return call_int_hook(audit_rule_match, 0, secid, field, op, lsmrule);
>   }
> +
> +int security_audit_enable(struct task_struct *tsk)
> +{
> +	return call_int_hook(audit_enable, 0, tsk);
> +}
>   #endif /* CONFIG_AUDIT */
>   
>   #ifdef CONFIG_BPF_SYSCALL
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index d55571c585ff..88764aa0ab43 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -6628,6 +6628,16 @@ static void selinux_ib_free_security(void *ib_sec)
>   }
>   #endif
>   
> +#ifdef CONFIG_AUDIT
> +static int selinux_audit_enable(struct task_struct *tsk)
> +{
> +	u32 sid = current_sid();
> +
> +	return !avc_has_perm(&selinux_state, sid, sid, SECCLASS_PROCESS2,
> +			PROCESS2__AUDIT_ENABLE, NULL);
> +}
> +#endif
> +
>   #ifdef CONFIG_BPF_SYSCALL
>   static int selinux_bpf(int cmd, union bpf_attr *attr,
>   				     unsigned int size)
> @@ -6999,6 +7009,7 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
>   	LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
>   	LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
>   	LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
> +	LSM_HOOK_INIT(audit_enable, selinux_audit_enable),
>   #endif
>   
>   #ifdef CONFIG_BPF_SYSCALL
> diff --git a/security/selinux/include/classmap.h b/security/selinux/include/classmap.h
> index 32e9b03be3dd..d7d856cbd486 100644
> --- a/security/selinux/include/classmap.h
> +++ b/security/selinux/include/classmap.h
> @@ -52,7 +52,7 @@ struct security_class_mapping secclass_map[] = {
>   	    "execmem", "execstack", "execheap", "setkeycreate",
>   	    "setsockcreate", "getrlimit", NULL } },
>   	{ "process2",
> -	  { "nnp_transition", "nosuid_transition", NULL } },
> +	  { "nnp_transition", "nosuid_transition", "audit_enable", NULL } },
>   	{ "system",
>   	  { "ipc_info", "syslog_read", "syslog_mod",
>   	    "syslog_console", "module_request", "module_load", NULL } },
> 


^ permalink raw reply

* Re: [RFC][PATCH] fix d_absolute_path() interplay with fsmount()
From: Tetsuo Handa @ 2019-08-30 10:11 UTC (permalink / raw)
  To: Al Viro
  Cc: John Johansen, Eric W. Biederman, David Howells, linux-api,
	linux-fsdevel, torvalds, linux-security-module
In-Reply-To: <20190822035134.GK1131@ZenIV.linux.org.uk>

On 2019/08/22 12:51, Al Viro wrote:
> [bringing a private thread back to the lists]
> 
> There's a bug in interplay of fsmount() and d_absolute_path().
> Namely, the check in d_absolute_path() treats the
> not-yet-attached mount as "reached absolute root".

I think you can send this patch to linux-next.

^ permalink raw reply

* Re: [RFC/RFT v4 5/5] KEYS: trusted: Add generic trusted keys framework
From: Sumit Garg @ 2019-08-30  9:19 UTC (permalink / raw)
  To: keyrings, linux-integrity,
	open list:HARDWARE RANDOM NUMBER GENERATOR CORE,
	linux-security-module, Jarkko Sakkinen, Mimi Zohar
  Cc: dhowells, Herbert Xu, davem, peterhuewe, jgg, jejb, Arnd Bergmann,
	Greg Kroah-Hartman, James Morris, Serge E. Hallyn,
	Casey Schaufler, Ard Biesheuvel, Daniel Thompson,
	Linux Kernel Mailing List, tee-dev @ lists . linaro . org
In-Reply-To: <1565682784-10234-6-git-send-email-sumit.garg@linaro.org>

On Tue, 13 Aug 2019 at 13:24, Sumit Garg <sumit.garg@linaro.org> wrote:
>
> Current trusted keys framework is tightly coupled to use TPM device as
> an underlying implementation which makes it difficult for implementations
> like Trusted Execution Environment (TEE) etc. to provide trusked keys
> support in case platform doesn't posses a TPM device.
>
> So this patch tries to add generic trusted keys framework where underlying
> implemtations like TPM, TEE etc. could be easily plugged-in.
>
> Suggested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
> ---
>  include/keys/trusted-type.h                 |  45 ++++
>  include/keys/trusted_tpm.h                  |  15 --
>  security/keys/trusted-keys/Makefile         |   1 +
>  security/keys/trusted-keys/trusted-common.c | 343 +++++++++++++++++++++++++++
>  security/keys/trusted-keys/trusted-tpm.c    | 345 +++++-----------------------
>  5 files changed, 447 insertions(+), 302 deletions(-)
>  create mode 100644 security/keys/trusted-keys/trusted-common.c
>

Any comments/feedback on this patch before I send next version of TEE
patch-set with this patch included?

-Sumit

> diff --git a/include/keys/trusted-type.h b/include/keys/trusted-type.h
> index a94c03a..5559010 100644
> --- a/include/keys/trusted-type.h
> +++ b/include/keys/trusted-type.h
> @@ -40,6 +40,51 @@ struct trusted_key_options {
>         uint32_t policyhandle;
>  };
>
> +struct trusted_key_ops {
> +       /*
> +        * flag to indicate if trusted key implementation supports migration
> +        * or not.
> +        */
> +       unsigned char migratable;
> +
> +       /* trusted key init */
> +       int (*init)(void);
> +
> +       /* seal a trusted key */
> +       int (*seal)(struct trusted_key_payload *p, char *datablob);
> +
> +       /* unseal a trusted key */
> +       int (*unseal)(struct trusted_key_payload *p, char *datablob);
> +
> +       /* get random trusted key */
> +       int (*get_random)(unsigned char *key, size_t key_len);
> +
> +       /* trusted key cleanup */
> +       void (*cleanup)(void);
> +};
> +
>  extern struct key_type key_type_trusted;
> +#if defined(CONFIG_TCG_TPM)
> +extern struct trusted_key_ops tpm_trusted_key_ops;
> +#endif
> +
> +#define TRUSTED_DEBUG 0
> +
> +#if TRUSTED_DEBUG
> +static inline void dump_payload(struct trusted_key_payload *p)
> +{
> +       pr_info("trusted_key: key_len %d\n", p->key_len);
> +       print_hex_dump(KERN_INFO, "key ", DUMP_PREFIX_NONE,
> +                      16, 1, p->key, p->key_len, 0);
> +       pr_info("trusted_key: bloblen %d\n", p->blob_len);
> +       print_hex_dump(KERN_INFO, "blob ", DUMP_PREFIX_NONE,
> +                      16, 1, p->blob, p->blob_len, 0);
> +       pr_info("trusted_key: migratable %d\n", p->migratable);
> +}
> +#else
> +static inline void dump_payload(struct trusted_key_payload *p)
> +{
> +}
> +#endif
>
>  #endif /* _KEYS_TRUSTED_TYPE_H */
> diff --git a/include/keys/trusted_tpm.h b/include/keys/trusted_tpm.h
> index 0d72106..7b59344 100644
> --- a/include/keys/trusted_tpm.h
> +++ b/include/keys/trusted_tpm.h
> @@ -57,17 +57,6 @@ static inline void dump_options(struct trusted_key_options *o)
>                        16, 1, o->pcrinfo, o->pcrinfo_len, 0);
>  }
>
> -static inline void dump_payload(struct trusted_key_payload *p)
> -{
> -       pr_info("trusted_key: key_len %d\n", p->key_len);
> -       print_hex_dump(KERN_INFO, "key ", DUMP_PREFIX_NONE,
> -                      16, 1, p->key, p->key_len, 0);
> -       pr_info("trusted_key: bloblen %d\n", p->blob_len);
> -       print_hex_dump(KERN_INFO, "blob ", DUMP_PREFIX_NONE,
> -                      16, 1, p->blob, p->blob_len, 0);
> -       pr_info("trusted_key: migratable %d\n", p->migratable);
> -}
> -
>  static inline void dump_sess(struct osapsess *s)
>  {
>         print_hex_dump(KERN_INFO, "trusted-key: handle ", DUMP_PREFIX_NONE,
> @@ -93,10 +82,6 @@ static inline void dump_options(struct trusted_key_options *o)
>  {
>  }
>
> -static inline void dump_payload(struct trusted_key_payload *p)
> -{
> -}
> -
>  static inline void dump_sess(struct osapsess *s)
>  {
>  }
> diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile
> index fb42e94..9a4f721 100644
> --- a/security/keys/trusted-keys/Makefile
> +++ b/security/keys/trusted-keys/Makefile
> @@ -4,5 +4,6 @@
>  #
>
>  obj-$(CONFIG_TRUSTED_KEYS) += trusted.o
> +trusted-y += trusted-common.o
>  trusted-y += trusted-tpm.o
>  trusted-y += trusted-tpm2.o
> diff --git a/security/keys/trusted-keys/trusted-common.c b/security/keys/trusted-keys/trusted-common.c
> new file mode 100644
> index 0000000..8f00fde
> --- /dev/null
> +++ b/security/keys/trusted-keys/trusted-common.c
> @@ -0,0 +1,343 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2010 IBM Corporation
> + * Copyright (c) 2019, Linaro Limited
> + *
> + * Author:
> + * David Safford <safford@us.ibm.com>
> + * Added generic trusted key framework: Sumit Garg <sumit.garg@linaro.org>
> + *
> + * See Documentation/security/keys/trusted-encrypted.rst
> + */
> +
> +#include <keys/user-type.h>
> +#include <keys/trusted-type.h>
> +#include <linux/capability.h>
> +#include <linux/err.h>
> +#include <linux/init.h>
> +#include <linux/key-type.h>
> +#include <linux/module.h>
> +#include <linux/parser.h>
> +#include <linux/rcupdate.h>
> +#include <linux/slab.h>
> +#include <linux/string.h>
> +#include <linux/uaccess.h>
> +
> +static struct trusted_key_ops *available_tk_ops[] = {
> +#if defined(CONFIG_TCG_TPM)
> +       &tpm_trusted_key_ops,
> +#endif
> +};
> +static struct trusted_key_ops *tk_ops;
> +
> +enum {
> +       Opt_err,
> +       Opt_new, Opt_load, Opt_update,
> +};
> +
> +static const match_table_t key_tokens = {
> +       {Opt_new, "new"},
> +       {Opt_load, "load"},
> +       {Opt_update, "update"},
> +       {Opt_err, NULL}
> +};
> +
> +/*
> + * datablob_parse - parse the keyctl data and fill in the
> + *                  payload structure
> + *
> + * On success returns 0, otherwise -EINVAL.
> + */
> +static int datablob_parse(char *datablob, struct trusted_key_payload *p)
> +{
> +       substring_t args[MAX_OPT_ARGS];
> +       long keylen;
> +       int ret = -EINVAL;
> +       int key_cmd;
> +       char *c;
> +
> +       /* main command */
> +       c = strsep(&datablob, " \t");
> +       if (!c)
> +               return -EINVAL;
> +       key_cmd = match_token(c, key_tokens, args);
> +       switch (key_cmd) {
> +       case Opt_new:
> +               /* first argument is key size */
> +               c = strsep(&datablob, " \t");
> +               if (!c)
> +                       return -EINVAL;
> +               ret = kstrtol(c, 10, &keylen);
> +               if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE)
> +                       return -EINVAL;
> +               p->key_len = keylen;
> +               ret = Opt_new;
> +               break;
> +       case Opt_load:
> +               /* first argument is sealed blob */
> +               c = strsep(&datablob, " \t");
> +               if (!c)
> +                       return -EINVAL;
> +               p->blob_len = strlen(c) / 2;
> +               if (p->blob_len > MAX_BLOB_SIZE)
> +                       return -EINVAL;
> +               ret = hex2bin(p->blob, c, p->blob_len);
> +               if (ret < 0)
> +                       return -EINVAL;
> +               ret = Opt_load;
> +               break;
> +       case Opt_update:
> +               ret = Opt_update;
> +               break;
> +       case Opt_err:
> +               return -EINVAL;
> +       }
> +       return ret;
> +}
> +
> +static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
> +{
> +       struct trusted_key_payload *p = NULL;
> +       int ret;
> +
> +       ret = key_payload_reserve(key, sizeof(*p));
> +       if (ret < 0)
> +               return p;
> +       p = kzalloc(sizeof(*p), GFP_KERNEL);
> +
> +       p->migratable = tk_ops->migratable;
> +
> +       return p;
> +}
> +
> +/*
> + * trusted_instantiate - create a new trusted key
> + *
> + * Unseal an existing trusted blob or, for a new key, get a
> + * random key, then seal and create a trusted key-type key,
> + * adding it to the specified keyring.
> + *
> + * On success, return 0. Otherwise return errno.
> + */
> +static int trusted_instantiate(struct key *key,
> +                              struct key_preparsed_payload *prep)
> +{
> +       struct trusted_key_payload *payload = NULL;
> +       size_t datalen = prep->datalen;
> +       char *datablob;
> +       int ret = 0;
> +       int key_cmd;
> +       size_t key_len;
> +
> +       if (datalen <= 0 || datalen > 32767 || !prep->data)
> +               return -EINVAL;
> +
> +       datablob = kmalloc(datalen + 1, GFP_KERNEL);
> +       if (!datablob)
> +               return -ENOMEM;
> +       memcpy(datablob, prep->data, datalen);
> +       datablob[datalen] = '\0';
> +
> +       payload = trusted_payload_alloc(key);
> +       if (!payload) {
> +               ret = -ENOMEM;
> +               goto out;
> +       }
> +
> +       key_cmd = datablob_parse(datablob, payload);
> +       if (key_cmd < 0) {
> +               ret = key_cmd;
> +               goto out;
> +       }
> +
> +       dump_payload(payload);
> +
> +       switch (key_cmd) {
> +       case Opt_load:
> +               ret = tk_ops->unseal(payload, datablob);
> +               dump_payload(payload);
> +               if (ret < 0)
> +                       pr_info("trusted_key: key_unseal failed (%d)\n", ret);
> +               break;
> +       case Opt_new:
> +               key_len = payload->key_len;
> +               ret = tk_ops->get_random(payload->key, key_len);
> +               if (ret != key_len) {
> +                       pr_info("trusted_key: key_create failed (%d)\n", ret);
> +                       goto out;
> +               }
> +
> +               ret = tk_ops->seal(payload, datablob);
> +               if (ret < 0)
> +                       pr_info("trusted_key: key_seal failed (%d)\n", ret);
> +               break;
> +       default:
> +               ret = -EINVAL;
> +       }
> +out:
> +       kzfree(datablob);
> +       if (!ret)
> +               rcu_assign_keypointer(key, payload);
> +       else
> +               kzfree(payload);
> +       return ret;
> +}
> +
> +static void trusted_rcu_free(struct rcu_head *rcu)
> +{
> +       struct trusted_key_payload *p;
> +
> +       p = container_of(rcu, struct trusted_key_payload, rcu);
> +       kzfree(p);
> +}
> +
> +/*
> + * trusted_update - reseal an existing key with new PCR values
> + */
> +static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
> +{
> +       struct trusted_key_payload *p;
> +       struct trusted_key_payload *new_p;
> +       size_t datalen = prep->datalen;
> +       char *datablob;
> +       int ret = 0;
> +
> +       if (key_is_negative(key))
> +               return -ENOKEY;
> +       p = key->payload.data[0];
> +       if (!p->migratable)
> +               return -EPERM;
> +       if (datalen <= 0 || datalen > 32767 || !prep->data)
> +               return -EINVAL;
> +
> +       datablob = kmalloc(datalen + 1, GFP_KERNEL);
> +       if (!datablob)
> +               return -ENOMEM;
> +
> +       new_p = trusted_payload_alloc(key);
> +       if (!new_p) {
> +               ret = -ENOMEM;
> +               goto out;
> +       }
> +
> +       memcpy(datablob, prep->data, datalen);
> +       datablob[datalen] = '\0';
> +       ret = datablob_parse(datablob, new_p);
> +       if (ret != Opt_update) {
> +               ret = -EINVAL;
> +               kzfree(new_p);
> +               goto out;
> +       }
> +
> +       /* copy old key values, and reseal with new pcrs */
> +       new_p->migratable = p->migratable;
> +       new_p->key_len = p->key_len;
> +       memcpy(new_p->key, p->key, p->key_len);
> +       dump_payload(p);
> +       dump_payload(new_p);
> +
> +       ret = tk_ops->seal(new_p, datablob);
> +       if (ret < 0) {
> +               pr_info("trusted_key: key_seal failed (%d)\n", ret);
> +               kzfree(new_p);
> +               goto out;
> +       }
> +
> +       rcu_assign_keypointer(key, new_p);
> +       call_rcu(&p->rcu, trusted_rcu_free);
> +out:
> +       kzfree(datablob);
> +       return ret;
> +}
> +
> +/*
> + * trusted_read - copy the sealed blob data to userspace in hex.
> + * On success, return to userspace the trusted key datablob size.
> + */
> +static long trusted_read(const struct key *key, char __user *buffer,
> +                        size_t buflen)
> +{
> +       const struct trusted_key_payload *p;
> +       char *ascii_buf;
> +       char *bufp;
> +       int i;
> +
> +       p = dereference_key_locked(key);
> +       if (!p)
> +               return -EINVAL;
> +
> +       if (buffer && buflen >= 2 * p->blob_len) {
> +               ascii_buf = kmalloc_array(2, p->blob_len, GFP_KERNEL);
> +               if (!ascii_buf)
> +                       return -ENOMEM;
> +
> +               bufp = ascii_buf;
> +               for (i = 0; i < p->blob_len; i++)
> +                       bufp = hex_byte_pack(bufp, p->blob[i]);
> +               if (copy_to_user(buffer, ascii_buf, 2 * p->blob_len) != 0) {
> +                       kzfree(ascii_buf);
> +                       return -EFAULT;
> +               }
> +               kzfree(ascii_buf);
> +       }
> +       return 2 * p->blob_len;
> +}
> +
> +/*
> + * trusted_destroy - clear and free the key's payload
> + */
> +static void trusted_destroy(struct key *key)
> +{
> +       kzfree(key->payload.data[0]);
> +}
> +
> +struct key_type key_type_trusted = {
> +       .name = "trusted",
> +       .instantiate = trusted_instantiate,
> +       .update = trusted_update,
> +       .destroy = trusted_destroy,
> +       .describe = user_describe,
> +       .read = trusted_read,
> +};
> +EXPORT_SYMBOL_GPL(key_type_trusted);
> +
> +static int __init init_trusted(void)
> +{
> +       int i, ret = 0;
> +
> +       for (i = 0; i < sizeof(available_tk_ops); i++) {
> +               tk_ops = available_tk_ops[i];
> +
> +               if (!(tk_ops && tk_ops->init && tk_ops->seal &&
> +                     tk_ops->unseal && tk_ops->get_random))
> +                       continue;
> +
> +               ret = tk_ops->init();
> +               if (ret) {
> +                       if (tk_ops->cleanup)
> +                               tk_ops->cleanup();
> +               } else {
> +                       break;
> +               }
> +       }
> +
> +       /*
> +        * encrypted_keys.ko depends on successful load of this module even if
> +        * trusted key implementation is not found.
> +        */
> +       if (ret == -ENODEV)
> +               return 0;
> +
> +       return ret;
> +}
> +
> +static void __exit cleanup_trusted(void)
> +{
> +       if (tk_ops->cleanup)
> +               tk_ops->cleanup();
> +}
> +
> +late_initcall(init_trusted);
> +module_exit(cleanup_trusted);
> +
> +MODULE_LICENSE("GPL");
> diff --git a/security/keys/trusted-keys/trusted-tpm.c b/security/keys/trusted-keys/trusted-tpm.c
> index 66687e7..dab7c32 100644
> --- a/security/keys/trusted-keys/trusted-tpm.c
> +++ b/security/keys/trusted-keys/trusted-tpm.c
> @@ -1,29 +1,26 @@
>  // SPDX-License-Identifier: GPL-2.0-only
>  /*
>   * Copyright (C) 2010 IBM Corporation
> + * Copyright (c) 2019, Linaro Limited
>   *
>   * Author:
>   * David Safford <safford@us.ibm.com>
> + * Switch to generic trusted key framework: Sumit Garg <sumit.garg@linaro.org>
>   *
>   * See Documentation/security/keys/trusted-encrypted.rst
>   */
>
>  #include <crypto/hash_info.h>
> -#include <linux/uaccess.h>
> -#include <linux/module.h>
>  #include <linux/init.h>
>  #include <linux/slab.h>
>  #include <linux/parser.h>
>  #include <linux/string.h>
>  #include <linux/err.h>
> -#include <keys/user-type.h>
>  #include <keys/trusted-type.h>
>  #include <linux/key-type.h>
> -#include <linux/rcupdate.h>
>  #include <linux/crypto.h>
>  #include <crypto/hash.h>
>  #include <crypto/sha.h>
> -#include <linux/capability.h>
>  #include <linux/tpm.h>
>  #include <linux/tpm_command.h>
>
> @@ -705,7 +702,6 @@ static int key_unseal(struct trusted_key_payload *p,
>
>  enum {
>         Opt_err,
> -       Opt_new, Opt_load, Opt_update,
>         Opt_keyhandle, Opt_keyauth, Opt_blobauth,
>         Opt_pcrinfo, Opt_pcrlock, Opt_migratable,
>         Opt_hash,
> @@ -714,9 +710,6 @@ enum {
>  };
>
>  static const match_table_t key_tokens = {
> -       {Opt_new, "new"},
> -       {Opt_load, "load"},
> -       {Opt_update, "update"},
>         {Opt_keyhandle, "keyhandle=%s"},
>         {Opt_keyauth, "keyauth=%s"},
>         {Opt_blobauth, "blobauth=%s"},
> @@ -843,71 +836,6 @@ static int getoptions(char *c, struct trusted_key_payload *pay,
>         return 0;
>  }
>
> -/*
> - * datablob_parse - parse the keyctl data and fill in the
> - *                 payload and options structures
> - *
> - * On success returns 0, otherwise -EINVAL.
> - */
> -static int datablob_parse(char *datablob, struct trusted_key_payload *p,
> -                         struct trusted_key_options *o)
> -{
> -       substring_t args[MAX_OPT_ARGS];
> -       long keylen;
> -       int ret = -EINVAL;
> -       int key_cmd;
> -       char *c;
> -
> -       /* main command */
> -       c = strsep(&datablob, " \t");
> -       if (!c)
> -               return -EINVAL;
> -       key_cmd = match_token(c, key_tokens, args);
> -       switch (key_cmd) {
> -       case Opt_new:
> -               /* first argument is key size */
> -               c = strsep(&datablob, " \t");
> -               if (!c)
> -                       return -EINVAL;
> -               ret = kstrtol(c, 10, &keylen);
> -               if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE)
> -                       return -EINVAL;
> -               p->key_len = keylen;
> -               ret = getoptions(datablob, p, o);
> -               if (ret < 0)
> -                       return ret;
> -               ret = Opt_new;
> -               break;
> -       case Opt_load:
> -               /* first argument is sealed blob */
> -               c = strsep(&datablob, " \t");
> -               if (!c)
> -                       return -EINVAL;
> -               p->blob_len = strlen(c) / 2;
> -               if (p->blob_len > MAX_BLOB_SIZE)
> -                       return -EINVAL;
> -               ret = hex2bin(p->blob, c, p->blob_len);
> -               if (ret < 0)
> -                       return -EINVAL;
> -               ret = getoptions(datablob, p, o);
> -               if (ret < 0)
> -                       return ret;
> -               ret = Opt_load;
> -               break;
> -       case Opt_update:
> -               /* all arguments are options */
> -               ret = getoptions(datablob, p, o);
> -               if (ret < 0)
> -                       return ret;
> -               ret = Opt_update;
> -               break;
> -       case Opt_err:
> -               return -EINVAL;
> -               break;
> -       }
> -       return ret;
> -}
> -
>  static struct trusted_key_options *trusted_options_alloc(void)
>  {
>         struct trusted_key_options *options;
> @@ -928,258 +856,99 @@ static struct trusted_key_options *trusted_options_alloc(void)
>         return options;
>  }
>
> -static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
> +static int tpm_tk_seal(struct trusted_key_payload *p, char *datablob)
>  {
> -       struct trusted_key_payload *p = NULL;
> -       int ret;
> -
> -       ret = key_payload_reserve(key, sizeof *p);
> -       if (ret < 0)
> -               return p;
> -       p = kzalloc(sizeof *p, GFP_KERNEL);
> -       if (p)
> -               p->migratable = 1; /* migratable by default */
> -       return p;
> -}
> -
> -/*
> - * trusted_instantiate - create a new trusted key
> - *
> - * Unseal an existing trusted blob or, for a new key, get a
> - * random key, then seal and create a trusted key-type key,
> - * adding it to the specified keyring.
> - *
> - * On success, return 0. Otherwise return errno.
> - */
> -static int trusted_instantiate(struct key *key,
> -                              struct key_preparsed_payload *prep)
> -{
> -       struct trusted_key_payload *payload = NULL;
>         struct trusted_key_options *options = NULL;
> -       size_t datalen = prep->datalen;
> -       char *datablob;
>         int ret = 0;
> -       int key_cmd;
> -       size_t key_len;
>         int tpm2;
>
>         tpm2 = tpm_is_tpm2(chip);
>         if (tpm2 < 0)
>                 return tpm2;
>
> -       if (datalen <= 0 || datalen > 32767 || !prep->data)
> -               return -EINVAL;
> -
> -       datablob = kmalloc(datalen + 1, GFP_KERNEL);
> -       if (!datablob)
> -               return -ENOMEM;
> -       memcpy(datablob, prep->data, datalen);
> -       datablob[datalen] = '\0';
> -
>         options = trusted_options_alloc();
> -       if (!options) {
> -               ret = -ENOMEM;
> -               goto out;
> -       }
> -       payload = trusted_payload_alloc(key);
> -       if (!payload) {
> -               ret = -ENOMEM;
> -               goto out;
> -       }
> +       if (!options)
> +               return -ENOMEM;
>
> -       key_cmd = datablob_parse(datablob, payload, options);
> -       if (key_cmd < 0) {
> -               ret = key_cmd;
> +       ret = getoptions(datablob, p, options);
> +       if (ret < 0)
>                 goto out;
> -       }
> +       dump_options(options);
>
>         if (!options->keyhandle) {
>                 ret = -EINVAL;
>                 goto out;
>         }
>
> -       dump_payload(payload);
> -       dump_options(options);
> +       if (tpm2)
> +               ret = tpm_seal_trusted(chip, p, options);
> +       else
> +               ret = key_seal(p, options);
> +       if (ret < 0) {
> +               pr_info("tpm_trusted_key: key_seal failed (%d)\n", ret);
> +               goto out;
> +       }
>
> -       switch (key_cmd) {
> -       case Opt_load:
> -               if (tpm2)
> -                       ret = tpm_unseal_trusted(chip, payload, options);
> -               else
> -                       ret = key_unseal(payload, options);
> -               dump_payload(payload);
> -               dump_options(options);
> -               if (ret < 0)
> -                       pr_info("trusted_key: key_unseal failed (%d)\n", ret);
> -               break;
> -       case Opt_new:
> -               key_len = payload->key_len;
> -               ret = tpm_get_random(chip, payload->key, key_len);
> -               if (ret != key_len) {
> -                       pr_info("trusted_key: key_create failed (%d)\n", ret);
> +       if (options->pcrlock) {
> +               ret = pcrlock(options->pcrlock);
> +               if (ret < 0) {
> +                       pr_info("tpm_trusted_key: pcrlock failed (%d)\n", ret);
>                         goto out;
>                 }
> -               if (tpm2)
> -                       ret = tpm_seal_trusted(chip, payload, options);
> -               else
> -                       ret = key_seal(payload, options);
> -               if (ret < 0)
> -                       pr_info("trusted_key: key_seal failed (%d)\n", ret);
> -               break;
> -       default:
> -               ret = -EINVAL;
> -               goto out;
>         }
> -       if (!ret && options->pcrlock)
> -               ret = pcrlock(options->pcrlock);
>  out:
> -       kzfree(datablob);
>         kzfree(options);
> -       if (!ret)
> -               rcu_assign_keypointer(key, payload);
> -       else
> -               kzfree(payload);
>         return ret;
>  }
>
> -static void trusted_rcu_free(struct rcu_head *rcu)
> -{
> -       struct trusted_key_payload *p;
> -
> -       p = container_of(rcu, struct trusted_key_payload, rcu);
> -       kzfree(p);
> -}
> -
> -/*
> - * trusted_update - reseal an existing key with new PCR values
> - */
> -static int trusted_update(struct key *key, struct key_preparsed_payload *prep)
> +static int tpm_tk_unseal(struct trusted_key_payload *p, char *datablob)
>  {
> -       struct trusted_key_payload *p;
> -       struct trusted_key_payload *new_p;
> -       struct trusted_key_options *new_o;
> -       size_t datalen = prep->datalen;
> -       char *datablob;
> +       struct trusted_key_options *options = NULL;
>         int ret = 0;
> +       int tpm2;
>
> -       if (key_is_negative(key))
> -               return -ENOKEY;
> -       p = key->payload.data[0];
> -       if (!p->migratable)
> -               return -EPERM;
> -       if (datalen <= 0 || datalen > 32767 || !prep->data)
> -               return -EINVAL;
> +       tpm2 = tpm_is_tpm2(chip);
> +       if (tpm2 < 0)
> +               return tpm2;
>
> -       datablob = kmalloc(datalen + 1, GFP_KERNEL);
> -       if (!datablob)
> +       options = trusted_options_alloc();
> +       if (!options)
>                 return -ENOMEM;
> -       new_o = trusted_options_alloc();
> -       if (!new_o) {
> -               ret = -ENOMEM;
> -               goto out;
> -       }
> -       new_p = trusted_payload_alloc(key);
> -       if (!new_p) {
> -               ret = -ENOMEM;
> -               goto out;
> -       }
>
> -       memcpy(datablob, prep->data, datalen);
> -       datablob[datalen] = '\0';
> -       ret = datablob_parse(datablob, new_p, new_o);
> -       if (ret != Opt_update) {
> -               ret = -EINVAL;
> -               kzfree(new_p);
> +       ret = getoptions(datablob, p, options);
> +       if (ret < 0)
>                 goto out;
> -       }
> +       dump_options(options);
>
> -       if (!new_o->keyhandle) {
> +       if (!options->keyhandle) {
>                 ret = -EINVAL;
> -               kzfree(new_p);
>                 goto out;
>         }
>
> -       /* copy old key values, and reseal with new pcrs */
> -       new_p->migratable = p->migratable;
> -       new_p->key_len = p->key_len;
> -       memcpy(new_p->key, p->key, p->key_len);
> -       dump_payload(p);
> -       dump_payload(new_p);
> +       if (tpm2)
> +               ret = tpm_unseal_trusted(chip, p, options);
> +       else
> +               ret = key_unseal(p, options);
> +       if (ret < 0)
> +               pr_info("tpm_trusted_key: key_unseal failed (%d)\n", ret);
>
> -       ret = key_seal(new_p, new_o);
> -       if (ret < 0) {
> -               pr_info("trusted_key: key_seal failed (%d)\n", ret);
> -               kzfree(new_p);
> -               goto out;
> -       }
> -       if (new_o->pcrlock) {
> -               ret = pcrlock(new_o->pcrlock);
> +       if (options->pcrlock) {
> +               ret = pcrlock(options->pcrlock);
>                 if (ret < 0) {
> -                       pr_info("trusted_key: pcrlock failed (%d)\n", ret);
> -                       kzfree(new_p);
> +                       pr_info("tpm_trusted_key: pcrlock failed (%d)\n", ret);
>                         goto out;
>                 }
>         }
> -       rcu_assign_keypointer(key, new_p);
> -       call_rcu(&p->rcu, trusted_rcu_free);
>  out:
> -       kzfree(datablob);
> -       kzfree(new_o);
> +       kzfree(options);
>         return ret;
>  }
>
> -/*
> - * trusted_read - copy the sealed blob data to userspace in hex.
> - * On success, return to userspace the trusted key datablob size.
> - */
> -static long trusted_read(const struct key *key, char __user *buffer,
> -                        size_t buflen)
> -{
> -       const struct trusted_key_payload *p;
> -       char *ascii_buf;
> -       char *bufp;
> -       int i;
> -
> -       p = dereference_key_locked(key);
> -       if (!p)
> -               return -EINVAL;
> -
> -       if (buffer && buflen >= 2 * p->blob_len) {
> -               ascii_buf = kmalloc_array(2, p->blob_len, GFP_KERNEL);
> -               if (!ascii_buf)
> -                       return -ENOMEM;
> -
> -               bufp = ascii_buf;
> -               for (i = 0; i < p->blob_len; i++)
> -                       bufp = hex_byte_pack(bufp, p->blob[i]);
> -               if (copy_to_user(buffer, ascii_buf, 2 * p->blob_len) != 0) {
> -                       kzfree(ascii_buf);
> -                       return -EFAULT;
> -               }
> -               kzfree(ascii_buf);
> -       }
> -       return 2 * p->blob_len;
> -}
> -
> -/*
> - * trusted_destroy - clear and free the key's payload
> - */
> -static void trusted_destroy(struct key *key)
> +int tpm_tk_get_random(unsigned char *key, size_t key_len)
>  {
> -       kzfree(key->payload.data[0]);
> +       return tpm_get_random(chip, key, key_len);
>  }
>
> -struct key_type key_type_trusted = {
> -       .name = "trusted",
> -       .instantiate = trusted_instantiate,
> -       .update = trusted_update,
> -       .destroy = trusted_destroy,
> -       .describe = user_describe,
> -       .read = trusted_read,
> -};
> -
> -EXPORT_SYMBOL_GPL(key_type_trusted);
> -
>  static void trusted_shash_release(void)
>  {
>         if (hashalg)
> @@ -1194,14 +963,14 @@ static int __init trusted_shash_alloc(void)
>
>         hmacalg = crypto_alloc_shash(hmac_alg, 0, 0);
>         if (IS_ERR(hmacalg)) {
> -               pr_info("trusted_key: could not allocate crypto %s\n",
> +               pr_info("tpm_trusted_key: could not allocate crypto %s\n",
>                         hmac_alg);
>                 return PTR_ERR(hmacalg);
>         }
>
>         hashalg = crypto_alloc_shash(hash_alg, 0, 0);
>         if (IS_ERR(hashalg)) {
> -               pr_info("trusted_key: could not allocate crypto %s\n",
> +               pr_info("tpm_trusted_key: could not allocate crypto %s\n",
>                         hash_alg);
>                 ret = PTR_ERR(hashalg);
>                 goto hashalg_fail;
> @@ -1237,16 +1006,13 @@ static int __init init_digests(void)
>         return 0;
>  }
>
> -static int __init init_trusted(void)
> +static int __init init_tpm_trusted(void)
>  {
>         int ret;
>
> -       /* encrypted_keys.ko depends on successful load of this module even if
> -        * TPM is not used.
> -        */
>         chip = tpm_default_chip();
>         if (!chip)
> -               return 0;
> +               return -ENODEV;
>
>         ret = init_digests();
>         if (ret < 0)
> @@ -1267,7 +1033,7 @@ static int __init init_trusted(void)
>         return ret;
>  }
>
> -static void __exit cleanup_trusted(void)
> +static void __exit cleanup_tpm_trusted(void)
>  {
>         if (chip) {
>                 put_device(&chip->dev);
> @@ -1277,7 +1043,12 @@ static void __exit cleanup_trusted(void)
>         }
>  }
>
> -late_initcall(init_trusted);
> -module_exit(cleanup_trusted);
> -
> -MODULE_LICENSE("GPL");
> +struct trusted_key_ops tpm_trusted_key_ops = {
> +       .migratable = 1, /* migratable by default */
> +       .init = init_tpm_trusted,
> +       .seal = tpm_tk_seal,
> +       .unseal = tpm_tk_unseal,
> +       .get_random = tpm_tk_get_random,
> +       .cleanup = cleanup_tpm_trusted,
> +};
> +EXPORT_SYMBOL_GPL(tpm_trusted_key_ops);
> --
> 2.7.4
>

^ permalink raw reply

* Re: [PATCH] tpm_tis: Fix interrupt probing
From: Stefan Berger @ 2019-08-30  0:11 UTC (permalink / raw)
  To: Jarkko Sakkinen
  Cc: Stefan Berger, linux-integrity, linux-security-module,
	linux-kernel
In-Reply-To: <20190829161057.22l72j55jy3dyib7@linux.intel.com>

On 8/29/19 12:10 PM, Jarkko Sakkinen wrote:
> On Thu, Aug 29, 2019 at 04:20:21PM +0300, Jarkko Sakkinen wrote:
>> On Tue, Aug 27, 2019 at 03:34:36PM -0400, Stefan Berger wrote:
>>> On 8/27/19 11:19 AM, Jarkko Sakkinen wrote:
>>>> On Tue, Aug 27, 2019 at 04:14:00PM +0300, Jarkko Sakkinen wrote:
>>>>> On Tue, Aug 20, 2019 at 08:25:17AM -0400, Stefan Berger wrote:
>>>>>> From: Stefan Berger <stefanb@linux.ibm.com>
>>>>>>
>>>>>> The interrupt probing of the TPM TIS was broken since we are trying to
>>>>>> run it without an active locality and without the TPM_CHIP_FLAG_IRQ set.
>>>>>>
>>>>>> Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
>>>>> Need these:
>>>>>
>>>>> Cc: linux-stable@vger.kernel.org
>>>>> Fixes: a3fbfae82b4c ("tpm: take TPM chip power gating out of tpm_transmit()")
>>>>>
>>>>> Thank you. I'll apply this to my tree.
>>>>>
>>>>> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
>>>> The commit went in the following form:
>>>>
>>>> http://git.infradead.org/users/jjs/linux-tpmdd.git/commit/9b558deab2c5d7dc23d5f7a4064892ede482ad32
>>> I saw you dropped the stetting of the IRQ flag - I needed it, otherwise it
>>> wouldn't execute certain code paths.
>> I explained why I removed that part. There was no any reasoning for
>> it. Also, it cannot be in the same commit if it fixes a diffent
>> issue.
> AFAIK they go with different fixes-tags.

I sent a separate patch for this. It looks like this bug goes back to 
when the TPM_CHIP_FLAG_IRQ was introduced in March 2019?!

    Stefan



^ permalink raw reply

* [PATCH] tpm_tis_core: Set TPM_CHIP_FLAG_IRQ before probing for interrupts
From: Stefan Berger @ 2019-08-30  0:09 UTC (permalink / raw)
  To: jarkko.sakkinen
  Cc: linux-security-module, linux-kernel, linux-integrity,
	Stefan Berger, linux-stable

From: Stefan Berger <stefanb@linux.ibm.com>

The tpm_tis_core has to set the TPM_CHIP_FLAG_IRQ before probing for
interrupts since there is no other place in the code that would set
it.

Cc: linux-stable@vger.kernel.org
Fixes: 570a36097f30 ("tpm: drop 'irq' from struct tpm_vendor_specific")
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
---
 drivers/char/tpm/tpm_tis_core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index ffa9048d8f6c..270f43acbb77 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -981,6 +981,7 @@ int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 		}
 
 		tpm_chip_start(chip);
+		chip->flags |= TPM_CHIP_FLAG_IRQ;
 		if (irq) {
 			tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED,
 						 irq);
-- 
2.14.5


^ permalink raw reply related

* [PATCH v8 02/28] LSM: Infrastructure management of the sock security
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Move management of the sock->sk_security blob out
of the individual security modules and into the security
infrastructure. Instead of allocating the blobs from within
the modules the modules tell the infrastructure how much
space is required, and the space is allocated there.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 include/linux/lsm_hooks.h         |  1 +
 security/apparmor/include/net.h   |  6 ++-
 security/apparmor/lsm.c           | 38 ++++-----------
 security/security.c               | 36 +++++++++++++-
 security/selinux/hooks.c          | 78 +++++++++++++++----------------
 security/selinux/include/objsec.h |  5 ++
 security/selinux/netlabel.c       | 23 ++++-----
 security/smack/smack.h            |  5 ++
 security/smack/smack_lsm.c        | 64 ++++++++++++-------------
 security/smack/smack_netfilter.c  |  8 ++--
 10 files changed, 144 insertions(+), 120 deletions(-)

diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index f9222a04968d..b353482ea348 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -2047,6 +2047,7 @@ struct lsm_blob_sizes {
 	int	lbs_cred;
 	int	lbs_file;
 	int	lbs_inode;
+	int	lbs_sock;
 	int	lbs_superblock;
 	int	lbs_ipc;
 	int	lbs_msg_msg;
diff --git a/security/apparmor/include/net.h b/security/apparmor/include/net.h
index 7334ac966d01..adac04e3b3cc 100644
--- a/security/apparmor/include/net.h
+++ b/security/apparmor/include/net.h
@@ -55,7 +55,11 @@ struct aa_sk_ctx {
 	struct aa_label *peer;
 };
 
-#define SK_CTX(X) ((X)->sk_security)
+static inline struct aa_sk_ctx *aa_sock(const struct sock *sk)
+{
+	return sk->sk_security + apparmor_blob_sizes.lbs_sock;
+}
+
 #define SOCK_ctx(X) SOCK_INODE(X)->i_security
 #define DEFINE_AUDIT_NET(NAME, OP, SK, F, T, P)				  \
 	struct lsm_network_audit NAME ## _net = { .sk = (SK),		  \
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index 49d664ddff44..2716e7731279 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -757,33 +757,15 @@ static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo
 	return error;
 }
 
-/**
- * apparmor_sk_alloc_security - allocate and attach the sk_security field
- */
-static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
-{
-	struct aa_sk_ctx *ctx;
-
-	ctx = kzalloc(sizeof(*ctx), flags);
-	if (!ctx)
-		return -ENOMEM;
-
-	SK_CTX(sk) = ctx;
-
-	return 0;
-}
-
 /**
  * apparmor_sk_free_security - free the sk_security field
  */
 static void apparmor_sk_free_security(struct sock *sk)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 
-	SK_CTX(sk) = NULL;
 	aa_put_label(ctx->label);
 	aa_put_label(ctx->peer);
-	kfree(ctx);
 }
 
 /**
@@ -792,8 +774,8 @@ static void apparmor_sk_free_security(struct sock *sk)
 static void apparmor_sk_clone_security(const struct sock *sk,
 				       struct sock *newsk)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
-	struct aa_sk_ctx *new = SK_CTX(newsk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
+	struct aa_sk_ctx *new = aa_sock(newsk);
 
 	new->label = aa_get_label(ctx->label);
 	new->peer = aa_get_label(ctx->peer);
@@ -844,7 +826,7 @@ static int apparmor_socket_post_create(struct socket *sock, int family,
 		label = aa_get_current_label();
 
 	if (sock->sk) {
-		struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
+		struct aa_sk_ctx *ctx = aa_sock(sock->sk);
 
 		aa_put_label(ctx->label);
 		ctx->label = aa_get_label(label);
@@ -1029,7 +1011,7 @@ static int apparmor_socket_shutdown(struct socket *sock, int how)
  */
 static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 
 	if (!skb->secmark)
 		return 0;
@@ -1042,7 +1024,7 @@ static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 
 static struct aa_label *sk_peer_label(struct sock *sk)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 
 	if (ctx->peer)
 		return ctx->peer;
@@ -1126,7 +1108,7 @@ static int apparmor_socket_getpeersec_dgram(struct socket *sock,
  */
 static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 
 	if (!ctx->label)
 		ctx->label = aa_get_current_label();
@@ -1136,7 +1118,7 @@ static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
 static int apparmor_inet_conn_request(struct sock *sk, struct sk_buff *skb,
 				      struct request_sock *req)
 {
-	struct aa_sk_ctx *ctx = SK_CTX(sk);
+	struct aa_sk_ctx *ctx = aa_sock(sk);
 
 	if (!skb->secmark)
 		return 0;
@@ -1153,6 +1135,7 @@ struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
 	.lbs_cred = sizeof(struct aa_task_ctx *),
 	.lbs_file = sizeof(struct aa_file_ctx),
 	.lbs_task = sizeof(struct aa_task_ctx),
+	.lbs_sock = sizeof(struct aa_sk_ctx),
 };
 
 static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
@@ -1189,7 +1172,6 @@ static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
 	LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
 
-	LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
 	LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
 	LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
 
@@ -1581,7 +1563,7 @@ static unsigned int apparmor_ip_postroute(void *priv,
 	if (sk == NULL)
 		return NF_ACCEPT;
 
-	ctx = SK_CTX(sk);
+	ctx = aa_sock(sk);
 	if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
 				    skb->secmark, sk))
 		return NF_ACCEPT;
diff --git a/security/security.c b/security/security.c
index 86198e303203..2c0834db7976 100644
--- a/security/security.c
+++ b/security/security.c
@@ -32,6 +32,7 @@
 #include <linux/string.h>
 #include <linux/msg.h>
 #include <net/flow.h>
+#include <net/sock.h>
 
 #define MAX_LSM_EVM_XATTR	2
 
@@ -172,6 +173,7 @@ static void __init lsm_set_blob_sizes(struct lsm_blob_sizes *needed)
 	lsm_set_blob_size(&needed->lbs_inode, &blob_sizes.lbs_inode);
 	lsm_set_blob_size(&needed->lbs_ipc, &blob_sizes.lbs_ipc);
 	lsm_set_blob_size(&needed->lbs_msg_msg, &blob_sizes.lbs_msg_msg);
+	lsm_set_blob_size(&needed->lbs_sock, &blob_sizes.lbs_sock);
 	lsm_set_blob_size(&needed->lbs_superblock, &blob_sizes.lbs_superblock);
 	lsm_set_blob_size(&needed->lbs_task, &blob_sizes.lbs_task);
 }
@@ -306,6 +308,7 @@ static void __init ordered_lsm_init(void)
 	init_debug("inode blob size      = %d\n", blob_sizes.lbs_inode);
 	init_debug("ipc blob size        = %d\n", blob_sizes.lbs_ipc);
 	init_debug("msg_msg blob size    = %d\n", blob_sizes.lbs_msg_msg);
+	init_debug("sock blob size       = %d\n", blob_sizes.lbs_sock);
 	init_debug("superblock blob size = %d\n", blob_sizes.lbs_superblock);
 	init_debug("task blob size       = %d\n", blob_sizes.lbs_task);
 
@@ -605,6 +608,28 @@ static void __init lsm_early_task(struct task_struct *task)
 		panic("%s: Early task alloc failed.\n", __func__);
 }
 
+/**
+ * lsm_sock_alloc - allocate a composite sock blob
+ * @sock: the sock that needs a blob
+ * @priority: allocation mode
+ *
+ * Allocate the sock blob for all the modules
+ *
+ * Returns 0, or -ENOMEM if memory can't be allocated.
+ */
+static int lsm_sock_alloc(struct sock *sock, gfp_t priority)
+{
+	if (blob_sizes.lbs_sock == 0) {
+		sock->sk_security = NULL;
+		return 0;
+	}
+
+	sock->sk_security = kzalloc(blob_sizes.lbs_sock, priority);
+	if (sock->sk_security == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
 /**
  * lsm_superblock_alloc - allocate a composite superblock blob
  * @sb: the superblock that needs a blob
@@ -2048,12 +2073,21 @@ EXPORT_SYMBOL(security_socket_getpeersec_dgram);
 
 int security_sk_alloc(struct sock *sk, int family, gfp_t priority)
 {
-	return call_int_hook(sk_alloc_security, 0, sk, family, priority);
+	int rc = lsm_sock_alloc(sk, priority);
+
+	if (unlikely(rc))
+		return rc;
+	rc = call_int_hook(sk_alloc_security, 0, sk, family, priority);
+	if (unlikely(rc))
+		security_sk_free(sk);
+	return rc;
 }
 
 void security_sk_free(struct sock *sk)
 {
 	call_void_hook(sk_free_security, sk);
+	kfree(sk->sk_security);
+	sk->sk_security = NULL;
 }
 
 void security_sk_clone(const struct sock *sk, struct sock *newsk)
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 7478d8eda00a..5d74ed35b728 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -4319,7 +4319,7 @@ static int socket_sockcreate_sid(const struct task_security_struct *tsec,
 
 static int sock_has_perm(struct sock *sk, u32 perms)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct common_audit_data ad;
 	struct lsm_network_audit net = {0,};
 
@@ -4376,7 +4376,7 @@ static int selinux_socket_post_create(struct socket *sock, int family,
 	isec->initialized = LABEL_INITIALIZED;
 
 	if (sock->sk) {
-		sksec = sock->sk->sk_security;
+		sksec = selinux_sock(sock->sk);
 		sksec->sclass = sclass;
 		sksec->sid = sid;
 		/* Allows detection of the first association on this socket */
@@ -4392,8 +4392,8 @@ static int selinux_socket_post_create(struct socket *sock, int family,
 static int selinux_socket_socketpair(struct socket *socka,
 				     struct socket *sockb)
 {
-	struct sk_security_struct *sksec_a = socka->sk->sk_security;
-	struct sk_security_struct *sksec_b = sockb->sk->sk_security;
+	struct sk_security_struct *sksec_a = selinux_sock(socka->sk);
+	struct sk_security_struct *sksec_b = selinux_sock(sockb->sk);
 
 	sksec_a->peer_sid = sksec_b->sid;
 	sksec_b->peer_sid = sksec_a->sid;
@@ -4408,7 +4408,7 @@ static int selinux_socket_socketpair(struct socket *socka,
 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
 {
 	struct sock *sk = sock->sk;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	u16 family;
 	int err;
 
@@ -4540,7 +4540,7 @@ static int selinux_socket_connect_helper(struct socket *sock,
 					 struct sockaddr *address, int addrlen)
 {
 	struct sock *sk = sock->sk;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	int err;
 
 	err = sock_has_perm(sk, SOCKET__CONNECT);
@@ -4711,9 +4711,9 @@ static int selinux_socket_unix_stream_connect(struct sock *sock,
 					      struct sock *other,
 					      struct sock *newsk)
 {
-	struct sk_security_struct *sksec_sock = sock->sk_security;
-	struct sk_security_struct *sksec_other = other->sk_security;
-	struct sk_security_struct *sksec_new = newsk->sk_security;
+	struct sk_security_struct *sksec_sock = selinux_sock(sock);
+	struct sk_security_struct *sksec_other = selinux_sock(other);
+	struct sk_security_struct *sksec_new = selinux_sock(newsk);
 	struct common_audit_data ad;
 	struct lsm_network_audit net = {0,};
 	int err;
@@ -4745,8 +4745,8 @@ static int selinux_socket_unix_stream_connect(struct sock *sock,
 static int selinux_socket_unix_may_send(struct socket *sock,
 					struct socket *other)
 {
-	struct sk_security_struct *ssec = sock->sk->sk_security;
-	struct sk_security_struct *osec = other->sk->sk_security;
+	struct sk_security_struct *ssec = selinux_sock(sock->sk);
+	struct sk_security_struct *osec = selinux_sock(other->sk);
 	struct common_audit_data ad;
 	struct lsm_network_audit net = {0,};
 
@@ -4788,7 +4788,7 @@ static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
 				       u16 family)
 {
 	int err = 0;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	u32 sk_sid = sksec->sid;
 	struct common_audit_data ad;
 	struct lsm_network_audit net = {0,};
@@ -4821,7 +4821,7 @@ static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 {
 	int err;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	u16 family = sk->sk_family;
 	u32 sk_sid = sksec->sid;
 	struct common_audit_data ad;
@@ -4889,13 +4889,15 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 	return err;
 }
 
-static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
-					    int __user *optlen, unsigned len)
+static int selinux_socket_getpeersec_stream(struct socket *sock,
+					    char __user *optval,
+					    int __user *optlen,
+					    unsigned int len)
 {
 	int err = 0;
 	char *scontext;
 	u32 scontext_len;
-	struct sk_security_struct *sksec = sock->sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sock->sk);
 	u32 peer_sid = SECSID_NULL;
 
 	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
@@ -4955,34 +4957,27 @@ static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *
 
 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
 {
-	struct sk_security_struct *sksec;
-
-	sksec = kzalloc(sizeof(*sksec), priority);
-	if (!sksec)
-		return -ENOMEM;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 
 	sksec->peer_sid = SECINITSID_UNLABELED;
 	sksec->sid = SECINITSID_UNLABELED;
 	sksec->sclass = SECCLASS_SOCKET;
 	selinux_netlbl_sk_security_reset(sksec);
-	sk->sk_security = sksec;
 
 	return 0;
 }
 
 static void selinux_sk_free_security(struct sock *sk)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 
-	sk->sk_security = NULL;
 	selinux_netlbl_sk_security_free(sksec);
-	kfree(sksec);
 }
 
 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
-	struct sk_security_struct *newsksec = newsk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
+	struct sk_security_struct *newsksec = selinux_sock(newsk);
 
 	newsksec->sid = sksec->sid;
 	newsksec->peer_sid = sksec->peer_sid;
@@ -4996,7 +4991,7 @@ static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
 	if (!sk)
 		*secid = SECINITSID_ANY_SOCKET;
 	else {
-		struct sk_security_struct *sksec = sk->sk_security;
+		struct sk_security_struct *sksec = selinux_sock(sk);
 
 		*secid = sksec->sid;
 	}
@@ -5006,7 +5001,7 @@ static void selinux_sock_graft(struct sock *sk, struct socket *parent)
 {
 	struct inode_security_struct *isec =
 		inode_security_novalidate(SOCK_INODE(parent));
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 
 	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
 	    sk->sk_family == PF_UNIX)
@@ -5021,7 +5016,7 @@ static void selinux_sock_graft(struct sock *sk, struct socket *parent)
 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
 				      struct sk_buff *skb)
 {
-	struct sk_security_struct *sksec = ep->base.sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(ep->base.sk);
 	struct common_audit_data ad;
 	struct lsm_network_audit net = {0,};
 	u8 peerlbl_active;
@@ -5172,8 +5167,8 @@ static int selinux_sctp_bind_connect(struct sock *sk, int optname,
 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
 				  struct sock *newsk)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
-	struct sk_security_struct *newsksec = newsk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
+	struct sk_security_struct *newsksec = selinux_sock(newsk);
 
 	/* If policy does not support SECCLASS_SCTP_SOCKET then call
 	 * the non-sctp clone version.
@@ -5190,7 +5185,7 @@ static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
 				     struct request_sock *req)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	int err;
 	u16 family = req->rsk_ops->family;
 	u32 connsid;
@@ -5211,7 +5206,7 @@ static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
 static void selinux_inet_csk_clone(struct sock *newsk,
 				   const struct request_sock *req)
 {
-	struct sk_security_struct *newsksec = newsk->sk_security;
+	struct sk_security_struct *newsksec = selinux_sock(newsk);
 
 	newsksec->sid = req->secid;
 	newsksec->peer_sid = req->peer_secid;
@@ -5228,7 +5223,7 @@ static void selinux_inet_csk_clone(struct sock *newsk,
 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
 {
 	u16 family = sk->sk_family;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 
 	/* handle mapped IPv4 packets arriving via IPv6 sockets */
 	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
@@ -5312,7 +5307,7 @@ static int selinux_tun_dev_attach_queue(void *security)
 static int selinux_tun_dev_attach(struct sock *sk, void *security)
 {
 	struct tun_security_struct *tunsec = security;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 
 	/* we don't currently perform any NetLabel based labeling here and it
 	 * isn't clear that we would want to do so anyway; while we could apply
@@ -5353,7 +5348,7 @@ static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
 	int err = 0;
 	u32 perm;
 	struct nlmsghdr *nlh;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 
 	if (skb->len < NLMSG_HDRLEN) {
 		err = -EINVAL;
@@ -5494,7 +5489,7 @@ static unsigned int selinux_ip_output(struct sk_buff *skb,
 			return NF_ACCEPT;
 
 		/* standard practice, label using the parent socket */
-		sksec = sk->sk_security;
+		sksec = selinux_sock(sk);
 		sid = sksec->sid;
 	} else
 		sid = SECINITSID_KERNEL;
@@ -5533,7 +5528,7 @@ static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
 
 	if (sk == NULL)
 		return NF_ACCEPT;
-	sksec = sk->sk_security;
+	sksec = selinux_sock(sk);
 
 	ad.type = LSM_AUDIT_DATA_NET;
 	ad.u.net = &net;
@@ -5625,7 +5620,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb,
 		u32 skb_sid;
 		struct sk_security_struct *sksec;
 
-		sksec = sk->sk_security;
+		sksec = selinux_sock(sk);
 		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
 			return NF_DROP;
 		/* At this point, if the returned skb peerlbl is SECSID_NULL
@@ -5654,7 +5649,7 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb,
 	} else {
 		/* Locally generated packet, fetch the security label from the
 		 * associated socket. */
-		struct sk_security_struct *sksec = sk->sk_security;
+		struct sk_security_struct *sksec = selinux_sock(sk);
 		peer_sid = sksec->sid;
 		secmark_perm = PACKET__SEND;
 	}
@@ -6633,6 +6628,7 @@ struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
 	.lbs_inode = sizeof(struct inode_security_struct),
 	.lbs_ipc = sizeof(struct ipc_security_struct),
 	.lbs_msg_msg = sizeof(struct msg_security_struct),
+	.lbs_sock = sizeof(struct sk_security_struct),
 	.lbs_superblock = sizeof(struct superblock_security_struct),
 };
 
diff --git a/security/selinux/include/objsec.h b/security/selinux/include/objsec.h
index d08d7e5d2f93..29f02b8f8f31 100644
--- a/security/selinux/include/objsec.h
+++ b/security/selinux/include/objsec.h
@@ -194,4 +194,9 @@ static inline struct superblock_security_struct *selinux_superblock(
 	return superblock->s_security + selinux_blob_sizes.lbs_superblock;
 }
 
+static inline struct sk_security_struct *selinux_sock(const struct sock *sock)
+{
+	return sock->sk_security + selinux_blob_sizes.lbs_sock;
+}
+
 #endif /* _SELINUX_OBJSEC_H_ */
diff --git a/security/selinux/netlabel.c b/security/selinux/netlabel.c
index 186e727b737b..c40914a157b7 100644
--- a/security/selinux/netlabel.c
+++ b/security/selinux/netlabel.c
@@ -31,6 +31,7 @@
 #include <linux/gfp.h>
 #include <linux/ip.h>
 #include <linux/ipv6.h>
+#include <linux/lsm_hooks.h>
 #include <net/sock.h>
 #include <net/netlabel.h>
 #include <net/ip.h>
@@ -81,7 +82,7 @@ static int selinux_netlbl_sidlookup_cached(struct sk_buff *skb,
 static struct netlbl_lsm_secattr *selinux_netlbl_sock_genattr(struct sock *sk)
 {
 	int rc;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct netlbl_lsm_secattr *secattr;
 
 	if (sksec->nlbl_secattr != NULL)
@@ -114,7 +115,7 @@ static struct netlbl_lsm_secattr *selinux_netlbl_sock_getattr(
 							const struct sock *sk,
 							u32 sid)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct netlbl_lsm_secattr *secattr = sksec->nlbl_secattr;
 
 	if (secattr == NULL)
@@ -249,7 +250,7 @@ int selinux_netlbl_skbuff_setsid(struct sk_buff *skb,
 	 * being labeled by it's parent socket, if it is just exit */
 	sk = skb_to_full_sk(skb);
 	if (sk != NULL) {
-		struct sk_security_struct *sksec = sk->sk_security;
+		struct sk_security_struct *sksec = selinux_sock(sk);
 
 		if (sksec->nlbl_state != NLBL_REQSKB)
 			return 0;
@@ -287,7 +288,7 @@ int selinux_netlbl_sctp_assoc_request(struct sctp_endpoint *ep,
 {
 	int rc;
 	struct netlbl_lsm_secattr secattr;
-	struct sk_security_struct *sksec = ep->base.sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(ep->base.sk);
 	struct sockaddr *addr;
 	struct sockaddr_in addr4;
 #if IS_ENABLED(CONFIG_IPV6)
@@ -370,7 +371,7 @@ int selinux_netlbl_inet_conn_request(struct request_sock *req, u16 family)
  */
 void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 
 	if (family == PF_INET)
 		sksec->nlbl_state = NLBL_LABELED;
@@ -388,8 +389,8 @@ void selinux_netlbl_inet_csk_clone(struct sock *sk, u16 family)
  */
 void selinux_netlbl_sctp_sk_clone(struct sock *sk, struct sock *newsk)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
-	struct sk_security_struct *newsksec = newsk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
+	struct sk_security_struct *newsksec = selinux_sock(newsk);
 
 	newsksec->nlbl_state = sksec->nlbl_state;
 }
@@ -407,7 +408,7 @@ void selinux_netlbl_sctp_sk_clone(struct sock *sk, struct sock *newsk)
 int selinux_netlbl_socket_post_create(struct sock *sk, u16 family)
 {
 	int rc;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct netlbl_lsm_secattr *secattr;
 
 	if (family != PF_INET && family != PF_INET6)
@@ -522,7 +523,7 @@ int selinux_netlbl_socket_setsockopt(struct socket *sock,
 {
 	int rc = 0;
 	struct sock *sk = sock->sk;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct netlbl_lsm_secattr secattr;
 
 	if (selinux_netlbl_option(level, optname) &&
@@ -560,7 +561,7 @@ static int selinux_netlbl_socket_connect_helper(struct sock *sk,
 						struct sockaddr *addr)
 {
 	int rc;
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 	struct netlbl_lsm_secattr *secattr;
 
 	/* connected sockets are allowed to disconnect when the address family
@@ -599,7 +600,7 @@ static int selinux_netlbl_socket_connect_helper(struct sock *sk,
 int selinux_netlbl_socket_connect_locked(struct sock *sk,
 					 struct sockaddr *addr)
 {
-	struct sk_security_struct *sksec = sk->sk_security;
+	struct sk_security_struct *sksec = selinux_sock(sk);
 
 	if (sksec->nlbl_state != NLBL_REQSKB &&
 	    sksec->nlbl_state != NLBL_CONNLABELED)
diff --git a/security/smack/smack.h b/security/smack/smack.h
index caecbcba9942..4ac4bf3310d7 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -375,6 +375,11 @@ static inline struct smack_known **smack_ipc(const struct kern_ipc_perm *ipc)
 	return ipc->security + smack_blob_sizes.lbs_ipc;
 }
 
+static inline struct socket_smack *smack_sock(const struct sock *sock)
+{
+	return sock->sk_security + smack_blob_sizes.lbs_sock;
+}
+
 static inline struct superblock_smack *smack_superblock(
 					const struct super_block *superblock)
 {
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 807eff2ccce9..fd69e1bd841b 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -1439,7 +1439,7 @@ static int smack_inode_getsecurity(struct inode *inode,
 		if (sock == NULL || sock->sk == NULL)
 			return -EOPNOTSUPP;
 
-		ssp = sock->sk->sk_security;
+		ssp = smack_sock(sock->sk);
 
 		if (strcmp(name, XATTR_SMACK_IPIN) == 0)
 			isp = ssp->smk_in;
@@ -1821,7 +1821,7 @@ static int smack_file_receive(struct file *file)
 
 	if (inode->i_sb->s_magic == SOCKFS_MAGIC) {
 		sock = SOCKET_I(inode);
-		ssp = sock->sk->sk_security;
+		ssp = smack_sock(sock->sk);
 		tsp = smack_cred(current_cred());
 		/*
 		 * If the receiving process can't write to the
@@ -2231,11 +2231,7 @@ static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
 static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
 {
 	struct smack_known *skp = smk_of_current();
-	struct socket_smack *ssp;
-
-	ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
-	if (ssp == NULL)
-		return -ENOMEM;
+	struct socket_smack *ssp = smack_sock(sk);
 
 	/*
 	 * Sockets created by kernel threads receive web label.
@@ -2249,11 +2245,10 @@ static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
 	}
 	ssp->smk_packet = NULL;
 
-	sk->sk_security = ssp;
-
 	return 0;
 }
 
+#ifdef SMACK_IPV6_PORT_LABELING
 /**
  * smack_sk_free_security - Free a socket blob
  * @sk: the socket
@@ -2262,7 +2257,6 @@ static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
  */
 static void smack_sk_free_security(struct sock *sk)
 {
-#ifdef SMACK_IPV6_PORT_LABELING
 	struct smk_port_label *spp;
 
 	if (sk->sk_family == PF_INET6) {
@@ -2275,9 +2269,8 @@ static void smack_sk_free_security(struct sock *sk)
 		}
 		rcu_read_unlock();
 	}
-#endif
-	kfree(sk->sk_security);
 }
+#endif
 
 /**
 * smack_ipv4host_label - check host based restrictions
@@ -2395,7 +2388,7 @@ static struct smack_known *smack_ipv6host_label(struct sockaddr_in6 *sip)
 static int smack_netlabel(struct sock *sk, int labeled)
 {
 	struct smack_known *skp;
-	struct socket_smack *ssp = sk->sk_security;
+	struct socket_smack *ssp = smack_sock(sk);
 	int rc = 0;
 
 	/*
@@ -2440,7 +2433,7 @@ static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap)
 	int rc;
 	int sk_lbl;
 	struct smack_known *hkp;
-	struct socket_smack *ssp = sk->sk_security;
+	struct socket_smack *ssp = smack_sock(sk);
 	struct smk_audit_info ad;
 
 	rcu_read_lock();
@@ -2516,7 +2509,7 @@ static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
 {
 	struct sock *sk = sock->sk;
 	struct sockaddr_in6 *addr6;
-	struct socket_smack *ssp = sock->sk->sk_security;
+	struct socket_smack *ssp = smack_sock(sock->sk);
 	struct smk_port_label *spp;
 	unsigned short port = 0;
 
@@ -2603,7 +2596,7 @@ static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
 				int act)
 {
 	struct smk_port_label *spp;
-	struct socket_smack *ssp = sk->sk_security;
+	struct socket_smack *ssp = smack_sock(sk);
 	struct smack_known *skp = NULL;
 	unsigned short port;
 	struct smack_known *object;
@@ -2697,7 +2690,7 @@ static int smack_inode_setsecurity(struct inode *inode, const char *name,
 	if (sock == NULL || sock->sk == NULL)
 		return -EOPNOTSUPP;
 
-	ssp = sock->sk->sk_security;
+	ssp = smack_sock(sock->sk);
 
 	if (strcmp(name, XATTR_SMACK_IPIN) == 0)
 		ssp->smk_in = skp;
@@ -2745,7 +2738,7 @@ static int smack_socket_post_create(struct socket *sock, int family,
 	 * Sockets created by kernel threads receive web label.
 	 */
 	if (unlikely(current->flags & PF_KTHREAD)) {
-		ssp = sock->sk->sk_security;
+		ssp = smack_sock(sock->sk);
 		ssp->smk_in = &smack_known_web;
 		ssp->smk_out = &smack_known_web;
 	}
@@ -2770,8 +2763,8 @@ static int smack_socket_post_create(struct socket *sock, int family,
 static int smack_socket_socketpair(struct socket *socka,
 		                   struct socket *sockb)
 {
-	struct socket_smack *asp = socka->sk->sk_security;
-	struct socket_smack *bsp = sockb->sk->sk_security;
+	struct socket_smack *asp = smack_sock(socka->sk);
+	struct socket_smack *bsp = smack_sock(sockb->sk);
 
 	asp->smk_packet = bsp->smk_out;
 	bsp->smk_packet = asp->smk_out;
@@ -2825,7 +2818,7 @@ static int smack_socket_connect(struct socket *sock, struct sockaddr *sap,
 		return 0;
 
 #ifdef SMACK_IPV6_SECMARK_LABELING
-	ssp = sock->sk->sk_security;
+	ssp = smack_sock(sock->sk);
 #endif
 
 	switch (sock->sk->sk_family) {
@@ -3566,9 +3559,9 @@ static int smack_unix_stream_connect(struct sock *sock,
 {
 	struct smack_known *skp;
 	struct smack_known *okp;
-	struct socket_smack *ssp = sock->sk_security;
-	struct socket_smack *osp = other->sk_security;
-	struct socket_smack *nsp = newsk->sk_security;
+	struct socket_smack *ssp = smack_sock(sock);
+	struct socket_smack *osp = smack_sock(other);
+	struct socket_smack *nsp = smack_sock(newsk);
 	struct smk_audit_info ad;
 	int rc = 0;
 #ifdef CONFIG_AUDIT
@@ -3614,8 +3607,8 @@ static int smack_unix_stream_connect(struct sock *sock,
  */
 static int smack_unix_may_send(struct socket *sock, struct socket *other)
 {
-	struct socket_smack *ssp = sock->sk->sk_security;
-	struct socket_smack *osp = other->sk->sk_security;
+	struct socket_smack *ssp = smack_sock(sock->sk);
+	struct socket_smack *osp = smack_sock(other->sk);
 	struct smk_audit_info ad;
 	int rc;
 
@@ -3652,7 +3645,7 @@ static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg,
 	struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name;
 #endif
 #ifdef SMACK_IPV6_SECMARK_LABELING
-	struct socket_smack *ssp = sock->sk->sk_security;
+	struct socket_smack *ssp = smack_sock(sock->sk);
 	struct smack_known *rsp;
 #endif
 	int rc = 0;
@@ -3817,7 +3810,7 @@ static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip)
 static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 {
 	struct netlbl_lsm_secattr secattr;
-	struct socket_smack *ssp = sk->sk_security;
+	struct socket_smack *ssp = smack_sock(sk);
 	struct smack_known *skp = NULL;
 	int rc = 0;
 	struct smk_audit_info ad;
@@ -3934,7 +3927,7 @@ static int smack_socket_getpeersec_stream(struct socket *sock,
 	int slen = 1;
 	int rc = 0;
 
-	ssp = sock->sk->sk_security;
+	ssp = smack_sock(sock->sk);
 	if (ssp->smk_packet != NULL) {
 		rcp = ssp->smk_packet->smk_known;
 		slen = strlen(rcp) + 1;
@@ -3984,7 +3977,7 @@ static int smack_socket_getpeersec_dgram(struct socket *sock,
 
 	switch (family) {
 	case PF_UNIX:
-		ssp = sock->sk->sk_security;
+		ssp = smack_sock(sock->sk);
 		s = ssp->smk_out->smk_secid;
 		break;
 	case PF_INET:
@@ -3997,7 +3990,7 @@ static int smack_socket_getpeersec_dgram(struct socket *sock,
 		 * Translate what netlabel gave us.
 		 */
 		if (sock != NULL && sock->sk != NULL)
-			ssp = sock->sk->sk_security;
+			ssp = smack_sock(sock->sk);
 		netlbl_secattr_init(&secattr);
 		rc = netlbl_skbuff_getattr(skb, family, &secattr);
 		if (rc == 0) {
@@ -4035,7 +4028,7 @@ static void smack_sock_graft(struct sock *sk, struct socket *parent)
 	    (sk->sk_family != PF_INET && sk->sk_family != PF_INET6))
 		return;
 
-	ssp = sk->sk_security;
+	ssp = smack_sock(sk);
 	ssp->smk_in = skp;
 	ssp->smk_out = skp;
 	/* cssp->smk_packet is already set in smack_inet_csk_clone() */
@@ -4055,7 +4048,7 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
 {
 	u16 family = sk->sk_family;
 	struct smack_known *skp;
-	struct socket_smack *ssp = sk->sk_security;
+	struct socket_smack *ssp = smack_sock(sk);
 	struct netlbl_lsm_secattr secattr;
 	struct sockaddr_in addr;
 	struct iphdr *hdr;
@@ -4154,7 +4147,7 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
 static void smack_inet_csk_clone(struct sock *sk,
 				 const struct request_sock *req)
 {
-	struct socket_smack *ssp = sk->sk_security;
+	struct socket_smack *ssp = smack_sock(sk);
 	struct smack_known *skp;
 
 	if (req->peer_secid != 0) {
@@ -4558,6 +4551,7 @@ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
 	.lbs_inode = sizeof(struct inode_smack),
 	.lbs_ipc = sizeof(struct smack_known *),
 	.lbs_msg_msg = sizeof(struct smack_known *),
+	.lbs_sock = sizeof(struct socket_smack),
 	.lbs_superblock = sizeof(struct superblock_smack),
 };
 
@@ -4667,7 +4661,9 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(socket_getpeersec_stream, smack_socket_getpeersec_stream),
 	LSM_HOOK_INIT(socket_getpeersec_dgram, smack_socket_getpeersec_dgram),
 	LSM_HOOK_INIT(sk_alloc_security, smack_sk_alloc_security),
+#ifdef SMACK_IPV6_PORT_LABELING
 	LSM_HOOK_INIT(sk_free_security, smack_sk_free_security),
+#endif
 	LSM_HOOK_INIT(sock_graft, smack_sock_graft),
 	LSM_HOOK_INIT(inet_conn_request, smack_inet_conn_request),
 	LSM_HOOK_INIT(inet_csk_clone, smack_inet_csk_clone),
diff --git a/security/smack/smack_netfilter.c b/security/smack/smack_netfilter.c
index e36d17835d4f..701a1cc1bdcc 100644
--- a/security/smack/smack_netfilter.c
+++ b/security/smack/smack_netfilter.c
@@ -31,8 +31,8 @@ static unsigned int smack_ipv6_output(void *priv,
 	struct socket_smack *ssp;
 	struct smack_known *skp;
 
-	if (sk && sk->sk_security) {
-		ssp = sk->sk_security;
+	if (sk && smack_sock(sk)) {
+		ssp = smack_sock(sk);
 		skp = ssp->smk_out;
 		skb->secmark = skp->smk_secid;
 	}
@@ -49,8 +49,8 @@ static unsigned int smack_ipv4_output(void *priv,
 	struct socket_smack *ssp;
 	struct smack_known *skp;
 
-	if (sk && sk->sk_security) {
-		ssp = sk->sk_security;
+	if (sk && smack_sock(sk)) {
+		ssp = smack_sock(sk);
 		skp = ssp->smk_out;
 		skb->secmark = skp->smk_secid;
 	}
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 26/28] NET: Add SO_PEERCONTEXT for multiple LSMs
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

The getsockopt SO_PEERSEC provides the LSM based security
information for a single module, but for reasons of backward
compatibility cannot include the information for multiple
modules. A new option SO_PEERCONTEXT is added to report the
security "context" of multiple modules using a "compound" format

        lsm1\0value\0lsm2\0value\0

This is expected to be used by system services, including dbus-daemon.
The exact format of a compound context has been the subject of
considerable debate. This format was suggested by Simon McVittie,
a dbus maintainer with a significant stake in the format being
uasable.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 arch/alpha/include/uapi/asm/socket.h  |   1 +
 arch/mips/include/uapi/asm/socket.h   |   1 +
 arch/parisc/include/uapi/asm/socket.h |   1 +
 arch/sparc/include/uapi/asm/socket.h  |   1 +
 include/linux/lsm_hooks.h             |   9 +-
 include/linux/security.h              |  11 ++-
 include/uapi/asm-generic/socket.h     |   1 +
 net/core/sock.c                       |   7 +-
 security/apparmor/lsm.c               |  20 ++---
 security/security.c                   | 116 +++++++++++++++++++++++---
 security/selinux/hooks.c              |  20 ++---
 security/smack/smack_lsm.c            |  31 +++----
 12 files changed, 156 insertions(+), 63 deletions(-)

diff --git a/arch/alpha/include/uapi/asm/socket.h b/arch/alpha/include/uapi/asm/socket.h
index 976e89b116e5..019e5fa8bcda 100644
--- a/arch/alpha/include/uapi/asm/socket.h
+++ b/arch/alpha/include/uapi/asm/socket.h
@@ -121,6 +121,7 @@
 
 #define SO_RCVTIMEO_NEW         66
 #define SO_SNDTIMEO_NEW         67
+#define SO_PEERCONTEXT          68
 
 #if !defined(__KERNEL__)
 
diff --git a/arch/mips/include/uapi/asm/socket.h b/arch/mips/include/uapi/asm/socket.h
index d41765cfbc6e..df8d984d76ed 100644
--- a/arch/mips/include/uapi/asm/socket.h
+++ b/arch/mips/include/uapi/asm/socket.h
@@ -132,6 +132,7 @@
 
 #define SO_RCVTIMEO_NEW         66
 #define SO_SNDTIMEO_NEW         67
+#define SO_PEERCONTEXT          68
 
 #if !defined(__KERNEL__)
 
diff --git a/arch/parisc/include/uapi/asm/socket.h b/arch/parisc/include/uapi/asm/socket.h
index 66c5dd245ac7..9ae358309f46 100644
--- a/arch/parisc/include/uapi/asm/socket.h
+++ b/arch/parisc/include/uapi/asm/socket.h
@@ -113,6 +113,7 @@
 
 #define SO_RCVTIMEO_NEW         0x4040
 #define SO_SNDTIMEO_NEW         0x4041
+#define SO_PEERCONTEXT          0x4042
 
 #if !defined(__KERNEL__)
 
diff --git a/arch/sparc/include/uapi/asm/socket.h b/arch/sparc/include/uapi/asm/socket.h
index 9265a9eece15..e8a53ef65210 100644
--- a/arch/sparc/include/uapi/asm/socket.h
+++ b/arch/sparc/include/uapi/asm/socket.h
@@ -114,6 +114,7 @@
 
 #define SO_RCVTIMEO_NEW          0x0044
 #define SO_SNDTIMEO_NEW          0x0045
+#define SO_PEERCONTEXT           0x0046
 
 #if !defined(__KERNEL__)
 
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 33e5ab4af9f8..b0f788bf82b6 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -864,8 +864,8 @@
  *	SO_GETPEERSEC.  For tcp sockets this can be meaningful if the
  *	socket is associated with an ipsec SA.
  *	@sock is the local socket.
- *	@optval userspace memory where the security state is to be copied.
- *	@optlen userspace int where the module should copy the actual length
+ *	@optval memory where the security state is to be copied.
+ *	@optlen int where the module should copy the actual length
  *	of the security state.
  *	@len as input is the maximum length to copy to userspace provided
  *	by the caller.
@@ -1697,9 +1697,8 @@ union security_list_options {
 	int (*socket_setsockopt)(struct socket *sock, int level, int optname);
 	int (*socket_shutdown)(struct socket *sock, int how);
 	int (*socket_sock_rcv_skb)(struct sock *sk, struct sk_buff *skb);
-	int (*socket_getpeersec_stream)(struct socket *sock,
-					char __user *optval,
-					int __user *optlen, unsigned len);
+	int (*socket_getpeersec_stream)(struct socket *sock, char **optval,
+					int *optlen, unsigned len);
 	int (*socket_getpeersec_dgram)(struct socket *sock,
 					struct sk_buff *skb, u32 *secid);
 	int (*sk_alloc_security)(struct sock *sk, int family, gfp_t priority);
diff --git a/include/linux/security.h b/include/linux/security.h
index bdef0edd14c5..d134ccff46b4 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -130,7 +130,7 @@ struct lsmblob {
 #define LSMBLOB_NEEDED		-2	/* Slot requested on initialization */
 #define LSMBLOB_NOT_NEEDED	-3	/* Slot not requested */
 #define LSMBLOB_DISPLAY		-4	/* Use the "display" slot */
-#define LSMBLOB_FIRST		-5	/* Use the default "display" slot */
+#define LSMBLOB_COMPOUND	-5	/* A compound "display" */
 
 /**
  * lsmblob_init - initialize an lsmblob structure.
@@ -1325,7 +1325,8 @@ int security_socket_setsockopt(struct socket *sock, int level, int optname);
 int security_socket_shutdown(struct socket *sock, int how);
 int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb);
 int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
-				      int __user *optlen, unsigned len);
+				      int __user *optlen, unsigned len,
+				      int display);
 int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
 				     struct lsmblob *blob);
 int security_sk_alloc(struct sock *sk, int family, gfp_t priority);
@@ -1459,8 +1460,10 @@ static inline int security_sock_rcv_skb(struct sock *sk,
 	return 0;
 }
 
-static inline int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
-						    int __user *optlen, unsigned len)
+static inline int security_socket_getpeersec_stream(struct socket *sock,
+						    char __user *optval,
+						    int __user *optlen,
+						    unsigned len, int display)
 {
 	return -ENOPROTOOPT;
 }
diff --git a/include/uapi/asm-generic/socket.h b/include/uapi/asm-generic/socket.h
index 8c1391c89171..b38d080c2802 100644
--- a/include/uapi/asm-generic/socket.h
+++ b/include/uapi/asm-generic/socket.h
@@ -116,6 +116,7 @@
 
 #define SO_RCVTIMEO_NEW         66
 #define SO_SNDTIMEO_NEW         67
+#define SO_PEERCONTEXT          68
 
 #if !defined(__KERNEL__)
 
diff --git a/net/core/sock.c b/net/core/sock.c
index 782343bb925b..b0955a34167c 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -1412,7 +1412,12 @@ int sock_getsockopt(struct socket *sock, int level, int optname,
 		break;
 
 	case SO_PEERSEC:
-		return security_socket_getpeersec_stream(sock, optval, optlen, len);
+		return security_socket_getpeersec_stream(sock, optval, optlen,
+							 len, LSMBLOB_DISPLAY);
+
+	case SO_PEERCONTEXT:
+		return security_socket_getpeersec_stream(sock, optval, optlen,
+							 len, LSMBLOB_COMPOUND);
 
 	case SO_MARK:
 		v.val = sk->sk_mark;
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index ec2e39aa9a84..5d25959610f9 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -1037,10 +1037,8 @@ static struct aa_label *sk_peer_label(struct sock *sk)
  *
  * Note: for tcp only valid if using ipsec or cipso on lan
  */
-static int apparmor_socket_getpeersec_stream(struct socket *sock,
-					     char __user *optval,
-					     int __user *optlen,
-					     unsigned int len)
+static int apparmor_socket_getpeersec_stream(struct socket *sock, char **optval,
+					     int *optlen, unsigned int len)
 {
 	char *name;
 	int slen, error = 0;
@@ -1060,17 +1058,11 @@ static int apparmor_socket_getpeersec_stream(struct socket *sock,
 	if (slen < 0) {
 		error = -ENOMEM;
 	} else {
-		if (slen > len) {
+		if (slen > len)
 			error = -ERANGE;
-		} else if (copy_to_user(optval, name, slen)) {
-			error = -EFAULT;
-			goto out;
-		}
-		if (put_user(slen, optlen))
-			error = -EFAULT;
-out:
-		kfree(name);
-
+		else
+			*optval = name;
+		*optlen = slen;
 	}
 
 done:
diff --git a/security/security.c b/security/security.c
index 70aabbef51b2..8cb91f33c166 100644
--- a/security/security.c
+++ b/security/security.c
@@ -743,6 +743,42 @@ static int lsm_superblock_alloc(struct super_block *sb)
 	return 0;
 }
 
+/**
+ * append_ctx - append a lsm/context pair to a compound context
+ * @ctx: the existing compound context
+ * @ctxlen: size of the old context, including terminating nul byte
+ * @lsm: new lsm name, nul terminated
+ * @new: new context, possibly nul terminated
+ * @newlen: maximum size of @new
+ *
+ * replace @ctx with a new compound context, appending @newlsm and @new
+ * to @ctx. On exit the new data replaces the old, which is freed.
+ * @ctxlen is set to the new size, which includes a trailing nul byte.
+ *
+ * Returns 0 on success, -ENOMEM if no memory is available.
+ */
+static int append_ctx(char **ctx, int *ctxlen, const char *lsm, char *new,
+		      int newlen)
+{
+	char *final;
+	int llen;
+
+	llen = strlen(lsm) + 1;
+	newlen = strnlen(new, newlen) + 1;
+
+	final = kzalloc(*ctxlen + llen + newlen, GFP_KERNEL);
+	if (final == NULL)
+		return -ENOMEM;
+	if (*ctxlen)
+		memcpy(final, *ctx, *ctxlen);
+	memcpy(final + *ctxlen, lsm, llen);
+	memcpy(final + *ctxlen + llen, new, newlen);
+	kfree(*ctx);
+	*ctx = final;
+	*ctxlen = *ctxlen + llen + newlen;
+	return 0;
+}
+
 /*
  * Hook list operation macros.
  *
@@ -2126,8 +2162,8 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
 	hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
 		if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
 			continue;
-		if (lsm == NULL && *display != LSMBLOB_INVALID &&
-		    *display != hp->lsmid->slot)
+		if (lsm == NULL && display != NULL &&
+		    *display != LSMBLOB_INVALID && *display != hp->lsmid->slot)
 			continue;
 		return hp->hook.setprocattr(name, value, size);
 	}
@@ -2208,6 +2244,15 @@ void security_release_secctx(struct lsmcontext *cp)
 	struct security_hook_list *hp;
 	bool found = false;
 
+	if (cp->slot == LSMBLOB_INVALID)
+		return;
+
+	if (cp->slot == LSMBLOB_COMPOUND) {
+		kfree(cp->context);
+		found = true;
+		goto clear_out;
+	}
+
 	hlist_for_each_entry(hp, &security_hook_heads.release_secctx, list)
 		if (cp->slot == hp->lsmid->slot) {
 			hp->hook.release_secctx(cp->context, cp->len);
@@ -2215,6 +2260,7 @@ void security_release_secctx(struct lsmcontext *cp)
 			break;
 		}
 
+clear_out:
 	memset(cp, 0, sizeof(*cp));
 
 	if (!found)
@@ -2351,17 +2397,67 @@ int security_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 EXPORT_SYMBOL(security_sock_rcv_skb);
 
 int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
-				      int __user *optlen, unsigned len)
+				      int __user *optlen, unsigned len,
+				      int display)
 {
-	int display = lsm_task_display(current);
 	struct security_hook_list *hp;
+	char *final = NULL;
+	char *cp;
+	int rc = 0;
+	unsigned finallen = 0;
+	unsigned clen = 0;
 
-	hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_stream,
-			     list)
-		if (display == LSMBLOB_INVALID || display == hp->lsmid->slot)
-			return hp->hook.socket_getpeersec_stream(sock, optval,
-								 optlen, len);
-	return -ENOPROTOOPT;
+	switch (display) {
+	case LSMBLOB_DISPLAY:
+		rc = -ENOPROTOOPT;
+		display = lsm_task_display(current);
+		hlist_for_each_entry(hp,
+				&security_hook_heads.socket_getpeersec_stream,
+				list)
+			if (display == LSMBLOB_INVALID ||
+			    display == hp->lsmid->slot) {
+				rc = hp->hook.socket_getpeersec_stream(sock,
+							&final, &finallen, len);
+				break;
+			}
+		break;
+	case LSMBLOB_COMPOUND:
+		/*
+		 * A compound context, in the form [lsm\0value\0]...
+		 */
+		hlist_for_each_entry(hp,
+				&security_hook_heads.socket_getpeersec_stream,
+				list) {
+			rc = hp->hook.socket_getpeersec_stream(sock, &cp, &clen,
+							       len);
+			if (rc == -EINVAL || rc == -ENOPROTOOPT) {
+				rc = 0;
+				continue;
+			}
+			if (rc) {
+				kfree(final);
+				return rc;
+			}
+			rc = append_ctx(&final, &finallen, hp->lsmid->lsm,
+					cp, clen);
+		}
+		if (final == NULL)
+			return -EINVAL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (finallen > len)
+		rc = -ERANGE;
+	else if (copy_to_user(optval, final, finallen))
+		rc = -EFAULT;
+
+	if (put_user(finallen, optlen))
+		rc = -EFAULT;
+
+	kfree(final);
+	return rc;
 }
 
 int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 2844f2ab7706..c8d469cc1b27 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -4923,10 +4923,8 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
 	return err;
 }
 
-static int selinux_socket_getpeersec_stream(struct socket *sock,
-					    char __user *optval,
-					    int __user *optlen,
-					    unsigned int len)
+static int selinux_socket_getpeersec_stream(struct socket *sock, char **optval,
+					    int *optlen, unsigned int len)
 {
 	int err = 0;
 	char *scontext;
@@ -4946,18 +4944,12 @@ static int selinux_socket_getpeersec_stream(struct socket *sock,
 	if (err)
 		return err;
 
-	if (scontext_len > len) {
+	if (scontext_len > len)
 		err = -ERANGE;
-		goto out_len;
-	}
-
-	if (copy_to_user(optval, scontext, scontext_len))
-		err = -EFAULT;
+	else
+		*optval = scontext;
 
-out_len:
-	if (put_user(scontext_len, optlen))
-		err = -EFAULT;
-	kfree(scontext);
+	*optlen = scontext_len;
 	return err;
 }
 
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 7a30b8692b1e..40c75205a914 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -3919,28 +3919,29 @@ static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
  *
  * returns zero on success, an error code otherwise
  */
-static int smack_socket_getpeersec_stream(struct socket *sock,
-					  char __user *optval,
-					  int __user *optlen, unsigned len)
+static int smack_socket_getpeersec_stream(struct socket *sock, char **optval,
+					  int *optlen, unsigned len)
 {
-	struct socket_smack *ssp;
-	char *rcp = "";
-	int slen = 1;
+	struct socket_smack *ssp = smack_sock(sock->sk);
+	char *rcp;
+	int slen;
 	int rc = 0;
 
-	ssp = smack_sock(sock->sk);
-	if (ssp->smk_packet != NULL) {
-		rcp = ssp->smk_packet->smk_known;
-		slen = strlen(rcp) + 1;
+	if (ssp->smk_packet == NULL) {
+		*optlen = 0;
+		return -EINVAL;
 	}
 
+	rcp = ssp->smk_packet->smk_known;
+	slen = strlen(rcp) + 1;
 	if (slen > len)
 		rc = -ERANGE;
-	else if (copy_to_user(optval, rcp, slen) != 0)
-		rc = -EFAULT;
-
-	if (put_user(slen, optlen) != 0)
-		rc = -EFAULT;
+	else {
+		*optval = kstrdup(rcp, GFP_KERNEL);
+		if (*optval == NULL)
+			rc = -ENOMEM;
+	}
+	*optlen = slen;
 
 	return rc;
 }
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 27/28] LSM: Add /proc attr entry for full LSM context
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Add an entry /proc/.../attr/context which displays the full
process security "context" in compound format:'
        lsm1\0value\0lsm2\0value\0...
This entry is not writable.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 fs/proc/base.c      |  1 +
 security/security.c | 27 +++++++++++++++++++++++++++
 2 files changed, 28 insertions(+)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 7bf70e041315..79600df5f7a2 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2619,6 +2619,7 @@ static const struct pid_entry attr_dir_stuff[] = {
 	ATTR(NULL, "keycreate",		0666),
 	ATTR(NULL, "sockcreate",	0666),
 	ATTR(NULL, "display",		0666),
+	ATTR(NULL, "context",		0666),
 #ifdef CONFIG_SECURITY_SMACK
 	DIR("smack",			0555,
 	    proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops),
diff --git a/security/security.c b/security/security.c
index 8cb91f33c166..d151ac4a398b 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2082,6 +2082,10 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name,
 				char **value)
 {
 	struct security_hook_list *hp;
+	char *final = NULL;
+	char *cp;
+	int rc = 0;
+	int finallen = 0;
 	int display = lsm_task_display(current);
 	int slot = 0;
 
@@ -2099,6 +2103,29 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name,
 		return -ENOMEM;
 	}
 
+	if (!strcmp(name, "context")) {
+		hlist_for_each_entry(hp, &security_hook_heads.getprocattr,
+				     list) {
+			rc = hp->hook.getprocattr(p, "current", &cp);
+			if (rc == -EINVAL || rc == -ENOPROTOOPT)
+				continue;
+			if (rc < 0) {
+				kfree(final);
+				return rc;
+			}
+			rc = append_ctx(&final, &finallen, hp->lsmid->lsm,
+					cp, rc);
+			if (rc < 0) {
+				kfree(final);
+				return rc;
+			}
+		}
+		if (final == NULL)
+			return -EINVAL;
+		*value = final;
+		return finallen;
+	}
+
 	hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
 		if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
 			continue;
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 28/28] AppArmor: Remove the exclusive flag
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

With the inclusion of the "display" process attribute
mechanism AppArmor no longer needs to be treated as an
"exclusive" security module. Remove the flag that indicates
it is exclusive. Remove the stub getpeersec_dgram AppArmor
hook as it has no effect in the single LSM case and
interferes in the multiple LSM case.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 security/apparmor/lsm.c | 20 +-------------------
 1 file changed, 1 insertion(+), 19 deletions(-)

diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index 5d25959610f9..fb5d5af426c6 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -1071,22 +1071,6 @@ static int apparmor_socket_getpeersec_stream(struct socket *sock, char **optval,
 	return error;
 }
 
-/**
- * apparmor_socket_getpeersec_dgram - get security label of packet
- * @sock: the peer socket
- * @skb: packet data
- * @secid: pointer to where to put the secid of the packet
- *
- * Sets the netlabel socket state on sk from parent
- */
-static int apparmor_socket_getpeersec_dgram(struct socket *sock,
-					    struct sk_buff *skb, u32 *secid)
-
-{
-	/* TODO: requires secid support */
-	return -ENOPROTOOPT;
-}
-
 /**
  * apparmor_sock_graft - Initialize newly created socket
  * @sk: child sock
@@ -1190,8 +1174,6 @@ static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
 #endif
 	LSM_HOOK_INIT(socket_getpeersec_stream,
 		      apparmor_socket_getpeersec_stream),
-	LSM_HOOK_INIT(socket_getpeersec_dgram,
-		      apparmor_socket_getpeersec_dgram),
 	LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
 #ifdef CONFIG_NETWORK_SECMARK
 	LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
@@ -1702,7 +1684,7 @@ static int __init apparmor_init(void)
 
 DEFINE_LSM(apparmor) = {
 	.name = "apparmor",
-	.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
+	.flags = LSM_FLAG_LEGACY_MAJOR,
 	.enabled = &apparmor_enabled,
 	.blobs = &apparmor_blob_sizes,
 	.init = apparmor_init,
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 25/28] LSM: Provide an user space interface for the default display
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Create /sys/kernel/security/lsm_display_default which contains
the name of the security module used when no display value
has been set.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 security/inode.c | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/security/inode.c b/security/inode.c
index b7772a9b315e..538a4d6796da 100644
--- a/security/inode.c
+++ b/security/inode.c
@@ -321,6 +321,22 @@ static const struct file_operations lsm_ops = {
 	.read = lsm_read,
 	.llseek = generic_file_llseek,
 };
+
+static struct dentry *lsm_display_default_dentry;
+static ssize_t lsm_display_default_read(struct file *filp, char __user *buf,
+					size_t count, loff_t *ppos)
+{
+	const char *name = security_lsm_slot_name(0);
+
+	if (name == NULL)
+		return 0;
+	return simple_read_from_buffer(buf, count, ppos, name, strlen(name));
+}
+
+static const struct file_operations lsm_display_default_ops = {
+	.read = lsm_display_default_read,
+	.llseek = generic_file_llseek,
+};
 #endif
 
 static int __init securityfs_init(void)
@@ -337,8 +353,10 @@ static int __init securityfs_init(void)
 		return retval;
 	}
 #ifdef CONFIG_SECURITY
-	lsm_dentry = securityfs_create_file("lsm", 0444, NULL, NULL,
-						&lsm_ops);
+	lsm_dentry = securityfs_create_file("lsm", 0444, NULL, NULL, &lsm_ops);
+	lsm_display_default_dentry = securityfs_create_file(
+					"lsm_display_default", 0444, NULL,
+					NULL, &lsm_display_default_ops);
 #endif
 	return 0;
 }
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 23/28] Audit: Add subj_LSM fields when necessary
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Add record entries to identify subject data for all of the
security modules when there is more than one.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 drivers/android/binder.c                |  2 +-
 include/linux/audit.h                   |  1 +
 include/linux/security.h                |  9 ++++-
 include/net/scm.h                       |  3 +-
 kernel/audit.c                          | 40 ++++++++++++++++++-
 kernel/audit_fsnotify.c                 |  1 +
 kernel/auditfilter.c                    |  1 +
 kernel/auditsc.c                        | 10 +++--
 net/ipv4/ip_sockglue.c                  |  2 +-
 net/netfilter/nf_conntrack_netlink.c    |  4 +-
 net/netfilter/nf_conntrack_standalone.c |  2 +-
 net/netfilter/nfnetlink_queue.c         |  2 +-
 net/netlabel/netlabel_unlabeled.c       | 11 ++++--
 net/netlabel/netlabel_user.c            |  2 +-
 net/xfrm/xfrm_policy.c                  |  2 +
 net/xfrm/xfrm_state.c                   |  2 +
 security/integrity/ima/ima_api.c        |  1 +
 security/integrity/integrity_audit.c    |  1 +
 security/security.c                     | 51 +++++++++++++++++++++++--
 19 files changed, 124 insertions(+), 23 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 90bc4ce07cd2..cb44f59b9bbe 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -3121,7 +3121,7 @@ static void binder_transaction(struct binder_proc *proc,
 		struct lsmblob blob;
 
 		security_task_getsecid(proc->tsk, &blob);
-		ret = security_secid_to_secctx(&blob, &lsmctx);
+		ret = security_secid_to_secctx(&blob, &lsmctx, LSMBLOB_DISPLAY);
 		if (ret) {
 			return_error = BR_FAILED_REPLY;
 			return_error_param = ret;
diff --git a/include/linux/audit.h b/include/linux/audit.h
index 1e69d9fe16da..306b404d419c 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -152,6 +152,7 @@ extern void		    audit_log_link_denied(const char *operation);
 extern void		    audit_log_lost(const char *message);
 
 extern int audit_log_task_context(struct audit_buffer *ab);
+extern void audit_log_task_lsms(struct audit_buffer *ab);
 extern void audit_log_task_info(struct audit_buffer *ab);
 
 extern int		    audit_update_lsm_rules(void);
diff --git a/include/linux/security.h b/include/linux/security.h
index 7fcc94ec8e04..bdef0edd14c5 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -129,6 +129,8 @@ struct lsmblob {
 #define LSMBLOB_INVALID		-1	/* Not a valid LSM slot number */
 #define LSMBLOB_NEEDED		-2	/* Slot requested on initialization */
 #define LSMBLOB_NOT_NEEDED	-3	/* Slot not requested */
+#define LSMBLOB_DISPLAY		-4	/* Use the "display" slot */
+#define LSMBLOB_FIRST		-5	/* Use the default "display" slot */
 
 /**
  * lsmblob_init - initialize an lsmblob structure.
@@ -178,6 +180,8 @@ static inline bool lsmblob_equal(struct lsmblob *bloba, struct lsmblob *blobb)
 	return true;
 }
 
+const char *security_lsm_slot_name(int slot);
+
 /* These functions are in security/commoncap.c */
 extern int cap_capable(const struct cred *cred, struct user_namespace *ns,
 		       int cap, unsigned int opts);
@@ -482,7 +486,8 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
 			 size_t size);
 int security_netlink_send(struct sock *sk, struct sk_buff *skb);
 int security_ismaclabel(const char *name);
-int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp);
+int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp,
+			     int display);
 int security_secctx_to_secid(const char *secdata, u32 seclen,
 			     struct lsmblob *blob);
 void security_release_secctx(struct lsmcontext *cp);
@@ -1263,7 +1268,7 @@ static inline int security_ismaclabel(const char *name)
 }
 
 static inline int security_secid_to_secctx(struct lsmblob *blob,
-					   struct lsmcontext *cp)
+					   struct lsmcontext *cp, int display)
 {
 	return -EOPNOTSUPP;
 }
diff --git a/include/net/scm.h b/include/net/scm.h
index 4a6ad8caf423..8b5a4737e1b8 100644
--- a/include/net/scm.h
+++ b/include/net/scm.h
@@ -96,7 +96,8 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
 	int err;
 
 	if (test_bit(SOCK_PASSSEC, &sock->flags)) {
-		err = security_secid_to_secctx(&scm->lsmblob, &context);
+		err = security_secid_to_secctx(&scm->lsmblob, &context,
+					       LSMBLOB_DISPLAY);
 
 		if (!err) {
 			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY,
diff --git a/kernel/audit.c b/kernel/audit.c
index e1dfd9c6df36..45ea36f1f1c5 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -405,6 +405,7 @@ static int audit_log_config_change(char *function_name, u32 new, u32 old,
 	if (rc)
 		allow_changes = 0; /* Something weird, deny request */
 	audit_log_format(ab, " res=%d", allow_changes);
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 	return rc;
 }
@@ -1110,6 +1111,7 @@ static void audit_log_feature_change(int which, u32 old_feature, u32 new_feature
 	audit_log_format(ab, " feature=%s old=%u new=%u old_lock=%u new_lock=%u res=%d",
 			 audit_feature_names[which], !!old_feature, !!new_feature,
 			 !!old_lock, !!new_lock, res);
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 }
 
@@ -1360,6 +1362,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 					size--;
 				audit_log_n_untrustedstring(ab, data, size);
 			}
+			audit_log_task_lsms(ab);
 			audit_log_end(ab);
 		}
 		break;
@@ -1374,6 +1377,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 					 msg_type == AUDIT_ADD_RULE ?
 						"add_rule" : "remove_rule",
 					 audit_enabled);
+			audit_log_task_lsms(ab);
 			audit_log_end(ab);
 			return -EPERM;
 		}
@@ -1387,6 +1391,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		audit_log_common_recv_msg(audit_context(), &ab,
 					  AUDIT_CONFIG_CHANGE);
 		audit_log_format(ab, " op=trim res=1");
+		audit_log_task_lsms(ab);
 		audit_log_end(ab);
 		break;
 	case AUDIT_MAKE_EQUIV: {
@@ -1422,6 +1427,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		audit_log_format(ab, " new=");
 		audit_log_untrustedstring(ab, new);
 		audit_log_format(ab, " res=%d", !err);
+		audit_log_task_lsms(ab);
 		audit_log_end(ab);
 		kfree(old);
 		kfree(new);
@@ -1431,7 +1437,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		len = 0;
 		if (lsmblob_is_set(&audit_sig_lsm)) {
 			err = security_secid_to_secctx(&audit_sig_lsm,
-						       &context);
+						       &context, LSMBLOB_FIRST);
 			if (err)
 				return err;
 		}
@@ -1490,6 +1496,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 				 " old-log_passwd=%d new-log_passwd=%d res=%d",
 				 old.enabled, s.enabled, old.log_passwd,
 				 s.log_passwd, !err);
+		audit_log_task_lsms(ab);
 		audit_log_end(ab);
 		break;
 	}
@@ -2068,6 +2075,33 @@ void audit_log_key(struct audit_buffer *ab, char *key)
 		audit_log_format(ab, "(null)");
 }
 
+void audit_log_task_lsms(struct audit_buffer *ab)
+{
+	int i;
+	const char *lsm;
+	struct lsmblob blob;
+	struct lsmcontext context;
+
+	/*
+	 * Don't do anything unless there is more than one LSM
+	 * with a security context to report.
+	 */
+	if (security_lsm_slot_name(1) == NULL)
+		return;
+
+	security_task_getsecid(current, &blob);
+
+	for (i = 0; i < LSMBLOB_ENTRIES; i++) {
+		lsm = security_lsm_slot_name(i);
+		if (lsm == NULL)
+			break;
+		if (security_secid_to_secctx(&blob, &context, i))
+			continue;
+		audit_log_format(ab, " subj_%s=%s", lsm, context.context);
+		security_release_secctx(&context);
+	}
+}
+
 int audit_log_task_context(struct audit_buffer *ab)
 {
 	int error;
@@ -2078,7 +2112,7 @@ int audit_log_task_context(struct audit_buffer *ab)
 	if (!lsmblob_is_set(&blob))
 		return 0;
 
-	error = security_secid_to_secctx(&blob, &context);
+	error = security_secid_to_secctx(&blob, &context, LSMBLOB_FIRST);
 	if (error) {
 		if (error != -EINVAL)
 			goto error_path;
@@ -2185,6 +2219,7 @@ void audit_log_link_denied(const char *operation)
 	audit_log_format(ab, "op=%s", operation);
 	audit_log_task_info(ab);
 	audit_log_format(ab, " res=0");
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 }
 
@@ -2235,6 +2270,7 @@ static void audit_log_set_loginuid(kuid_t koldloginuid, kuid_t kloginuid,
 			 oldloginuid, loginuid, tty ? tty_name(tty) : "(none)",
 			 oldsessionid, sessionid, !rc);
 	audit_put_tty(tty);
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 }
 
diff --git a/kernel/audit_fsnotify.c b/kernel/audit_fsnotify.c
index 37ae95cfb7f4..3a00583fa7fa 100644
--- a/kernel/audit_fsnotify.c
+++ b/kernel/audit_fsnotify.c
@@ -135,6 +135,7 @@ static void audit_mark_log_rule_change(struct audit_fsnotify_mark *audit_mark, c
 	audit_log_untrustedstring(ab, audit_mark->path);
 	audit_log_key(ab, rule->filterkey);
 	audit_log_format(ab, " list=%d res=1", rule->listnr);
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 }
 
diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c
index 8f244c98bb57..508d784413da 100644
--- a/kernel/auditfilter.c
+++ b/kernel/auditfilter.c
@@ -1099,6 +1099,7 @@ static void audit_log_rule_change(char *action, struct audit_krule *rule, int re
 	audit_log_format(ab, " op=%s", action);
 	audit_log_key(ab, rule->filterkey);
 	audit_log_format(ab, " list=%d res=%d", rule->listnr, res);
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 }
 
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 0478680cd0a8..46d7a58babd2 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -954,7 +954,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 			 from_kuid(&init_user_ns, auid),
 			 from_kuid(&init_user_ns, uid), sessionid);
 	if (lsmblob_is_set(blob)) {
-		if (security_secid_to_secctx(blob, &lsmctx)) {
+		if (security_secid_to_secctx(blob, &lsmctx, LSMBLOB_FIRST)) {
 			audit_log_format(ab, " obj=(none)");
 			rc = 1;
 		} else {
@@ -1198,7 +1198,8 @@ static void show_special(struct audit_context *context, int *call_panic)
 			struct lsmblob blob;
 
 			lsmblob_init(&blob, osid);
-			if (security_secid_to_secctx(&blob, &lsmcxt)) {
+			if (security_secid_to_secctx(&blob, &lsmcxt,
+						     LSMBLOB_FIRST)) {
 				audit_log_format(ab, " osid=%u", osid);
 				*call_panic = 1;
 			} else {
@@ -1351,7 +1352,7 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
 		struct lsmcontext lsmctx;
 
 		lsmblob_init(&blob, n->osid);
-		if (security_secid_to_secctx(&blob, &lsmctx)) {
+		if (security_secid_to_secctx(&blob, &lsmctx, LSMBLOB_FIRST)) {
 			audit_log_format(ab, " osid=%u", n->osid);
 			if (call_panic)
 				*call_panic = 2;
@@ -1460,6 +1461,7 @@ static void audit_log_exit(void)
 
 	audit_log_task_info(ab);
 	audit_log_key(ab, context->filterkey);
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 
 	for (aux = context->aux; aux; aux = aux->next) {
@@ -2569,6 +2571,7 @@ void audit_core_dumps(long signr)
 		return;
 	audit_log_task(ab);
 	audit_log_format(ab, " sig=%ld res=1", signr);
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 }
 
@@ -2595,6 +2598,7 @@ void audit_seccomp(unsigned long syscall, long signr, int code)
 	audit_log_format(ab, " sig=%ld arch=%x syscall=%ld compat=%d ip=0x%lx code=0x%x",
 			 signr, syscall_get_arch(), syscall,
 			 in_compat_syscall(), KSTK_EIP(current), code);
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 }
 
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 80ae0c5a1301..447fe60af0cd 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -138,7 +138,7 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
 	if (err)
 		return;
 
-	err = security_secid_to_secctx(&lb, &context);
+	err = security_secid_to_secctx(&lb, &context, LSMBLOB_DISPLAY);
 	if (err)
 		return;
 
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 403307ff0fff..c870aebe99a3 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -333,7 +333,7 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
 	struct lsmcontext context;
 
 	lsmblob_init(&blob, ct->secmark);
-	ret = security_secid_to_secctx(&blob, &context);
+	ret = security_secid_to_secctx(&blob, &context, LSMBLOB_DISPLAY);
 	if (ret)
 		return 0;
 
@@ -621,7 +621,7 @@ static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
 	struct lsmcontext context;
 
 	lsmblob_init(&blob, ct->secmark);
-	ret = security_secid_to_secctx(&blob, &context);
+	ret = security_secid_to_secctx(&blob, &context, LSMBLOB_DISPLAY);
 	if (ret)
 		return 0;
 
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index fcb51ab2bb8b..60dd81eb6f89 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -177,7 +177,7 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 	struct lsmcontext context;
 
 	lsmblob_init(&blob, ct->secmark);
-	ret = security_secid_to_secctx(&blob, &context);
+	ret = security_secid_to_secctx(&blob, &context, LSMBLOB_DISPLAY);
 	if (ret)
 		return;
 
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 58d5bd7a376e..ad4bb3f9c7dc 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -318,7 +318,7 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, struct lsmcontext *context)
 	if (skb->secmark) {
 		/* Any LSM might be looking for the secmark */
 		lsmblob_init(&blob, skb->secmark);
-		security_secid_to_secctx(&blob, context);
+		security_secid_to_secctx(&blob, context, LSMBLOB_DISPLAY);
 	}
 
 	read_unlock_bh(&skb->sk->sk_callback_lock);
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 57ede7781c8f..cf34c163af20 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -450,7 +450,8 @@ int netlbl_unlhsh_add(struct net *net,
 unlhsh_add_return:
 	rcu_read_unlock();
 	if (audit_buf != NULL) {
-		if (security_secid_to_secctx(lsmblob, &context) == 0) {
+		if (security_secid_to_secctx(lsmblob, &context,
+					     LSMBLOB_FIRST) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s",
 					 context.context);
 			security_release_secctx(&context);
@@ -505,7 +506,8 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
 		if (dev != NULL)
 			dev_put(dev);
 		if (entry != NULL &&
-		    security_secid_to_secctx(&entry->lsmblob, &context) == 0) {
+		    security_secid_to_secctx(&entry->lsmblob, &context,
+					     LSMBLOB_FIRST) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s",
 					 context.context);
 			security_release_secctx(&context);
@@ -565,7 +567,8 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
 		if (dev != NULL)
 			dev_put(dev);
 		if (entry != NULL &&
-		    security_secid_to_secctx(&entry->lsmblob, &context) == 0) {
+		    security_secid_to_secctx(&entry->lsmblob, &context,
+					     LSMBLOB_FIRST) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s",
 					 context.context);
 			security_release_secctx(&context);
@@ -1136,7 +1139,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
 		lsmb = (struct lsmblob *)&addr6->lsmblob;
 	}
 
-	ret_val = security_secid_to_secctx(lsmb, &context);
+	ret_val = security_secid_to_secctx(lsmb, &context, LSMBLOB_FIRST);
 	if (ret_val != 0)
 		goto list_cb_failure;
 	ret_val = nla_put(cb_arg->skb,
diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
index 2d1307f65250..193200955dbd 100644
--- a/net/netlabel/netlabel_user.c
+++ b/net/netlabel/netlabel_user.c
@@ -114,7 +114,7 @@ struct audit_buffer *netlbl_audit_start_common(int type,
 
 	lsmblob_init(&blob, audit_info->secid);
 	if (audit_info->secid != 0 &&
-	    security_secid_to_secctx(&blob, &context) == 0) {
+	    security_secid_to_secctx(&blob, &context, LSMBLOB_FIRST) == 0) {
 		audit_log_format(audit_buf, " subj=%s", context.context);
 		security_release_secctx(&context);
 	}
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 8d1a898d0ba5..5a67b2e5d941 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -3996,6 +3996,7 @@ void xfrm_audit_policy_add(struct xfrm_policy *xp, int result, bool task_valid)
 	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
 	audit_log_format(audit_buf, " res=%u", result);
 	xfrm_audit_common_policyinfo(xp, audit_buf);
+	audit_log_task_lsms(audit_buf);
 	audit_log_end(audit_buf);
 }
 EXPORT_SYMBOL_GPL(xfrm_audit_policy_add);
@@ -4011,6 +4012,7 @@ void xfrm_audit_policy_delete(struct xfrm_policy *xp, int result,
 	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
 	audit_log_format(audit_buf, " res=%u", result);
 	xfrm_audit_common_policyinfo(xp, audit_buf);
+	audit_log_task_lsms(audit_buf);
 	audit_log_end(audit_buf);
 }
 EXPORT_SYMBOL_GPL(xfrm_audit_policy_delete);
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index 1bb971f46fc6..d6944123ca0e 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -2456,6 +2456,7 @@ void xfrm_audit_state_add(struct xfrm_state *x, int result, bool task_valid)
 	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
 	xfrm_audit_helper_sainfo(x, audit_buf);
 	audit_log_format(audit_buf, " res=%u", result);
+	audit_log_task_lsms(audit_buf);
 	audit_log_end(audit_buf);
 }
 EXPORT_SYMBOL_GPL(xfrm_audit_state_add);
@@ -2470,6 +2471,7 @@ void xfrm_audit_state_delete(struct xfrm_state *x, int result, bool task_valid)
 	xfrm_audit_helper_usrinfo(task_valid, audit_buf);
 	xfrm_audit_helper_sainfo(x, audit_buf);
 	audit_log_format(audit_buf, " res=%u", result);
+	audit_log_task_lsms(audit_buf);
 	audit_log_end(audit_buf);
 }
 EXPORT_SYMBOL_GPL(xfrm_audit_state_delete);
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 94b2a4840d81..1e96afcb2d8d 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -337,6 +337,7 @@ void ima_audit_measurement(struct integrity_iint_cache *iint,
 	audit_log_format(ab, " hash=\"%s:%s\"", algo_name, hash);
 
 	audit_log_task_info(ab);
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 
 	iint->flags |= IMA_AUDITED;
diff --git a/security/integrity/integrity_audit.c b/security/integrity/integrity_audit.c
index 82c98f7d217e..aca1c6bdcccd 100644
--- a/security/integrity/integrity_audit.c
+++ b/security/integrity/integrity_audit.c
@@ -57,5 +57,6 @@ void integrity_audit_msg(int audit_msgno, struct inode *inode,
 		audit_log_format(ab, " ino=%lu", inode->i_ino);
 	}
 	audit_log_format(ab, " res=%d", !result);
+	audit_log_task_lsms(ab);
 	audit_log_end(ab);
 }
diff --git a/security/security.c b/security/security.c
index 20805ad99ccd..70aabbef51b2 100644
--- a/security/security.c
+++ b/security/security.c
@@ -434,7 +434,31 @@ static int lsm_append(const char *new, char **result)
  * Pointers to the LSM id structures for local use.
  */
 static int lsm_slot __lsm_ro_after_init;
-static struct lsm_id *lsm_slotlist[LSMBLOB_ENTRIES];
+static struct lsm_id *lsm_slotlist[LSMBLOB_ENTRIES] __lsm_ro_after_init;
+
+/**
+ * security_lsm_slot_name - Get the name of the security module in a slot
+ * @slot: index into the "display" slot list.
+ *
+ * Provide the name of the security module associated with
+ * a display slot.
+ *
+ * If @slot is LSMBLOB_INVALID return the value
+ * for slot 0 if it has been set, otherwise NULL.
+ *
+ * Returns a pointer to the name string or NULL.
+ */
+const char *security_lsm_slot_name(int slot)
+{
+	if (slot == LSMBLOB_INVALID)
+		slot = 0;
+	else if (slot >= LSMBLOB_ENTRIES || slot < 0)
+		return NULL;
+
+	if (lsm_slotlist[slot] == NULL)
+		return NULL;
+	return lsm_slotlist[slot]->lsm;
+}
 
 /**
  * security_add_hooks - Add a modules hooks to the hook lists.
@@ -2121,13 +2145,32 @@ int security_ismaclabel(const char *name)
 }
 EXPORT_SYMBOL(security_ismaclabel);
 
-int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp)
+int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp,
+			     int display)
 {
 	struct security_hook_list *hp;
-	int display = lsm_task_display(current);
 
 	memset(cp, 0, sizeof(*cp));
 
+	/*
+	 * display either is the slot number use for formatting
+	 * or an instruction on which relative slot to use.
+	 */
+	if (display == LSMBLOB_DISPLAY)
+		display = lsm_task_display(current);
+	else if (display == LSMBLOB_FIRST)
+		display = LSMBLOB_INVALID;
+	else if (display < 0) {
+		WARN_ONCE(true,
+			"LSM: security_secid_to_secctx unknown display\n");
+		display = LSMBLOB_INVALID;
+	} else if (display >= lsm_slot) {
+		WARN_ONCE(true,
+			"LSM: security_secid_to_secctx invalid display\n");
+		display = LSMBLOB_INVALID;
+	}
+
+
 	hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
 		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
 			continue;
@@ -2138,7 +2181,7 @@ int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp)
 					&cp->context, &cp->len);
 		}
 	}
-	return 0;
+	return -EOPNOTSUPP;
 }
 EXPORT_SYMBOL(security_secid_to_secctx);
 
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 24/28] Audit: Include object data for all security modules
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

When there is more than one context displaying security
module extend what goes into the audit record by supplimenting
the "obj=" with an "obj_<lsm>=" for each such security
module.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 kernel/audit.h   |   4 +-
 kernel/auditsc.c | 110 ++++++++++++++++++++++++-----------------------
 2 files changed, 58 insertions(+), 56 deletions(-)

diff --git a/kernel/audit.h b/kernel/audit.h
index 29e29c6f4afb..af9a7d1fc069 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -91,7 +91,7 @@ struct audit_names {
 	kuid_t			uid;
 	kgid_t			gid;
 	dev_t			rdev;
-	u32			osid;
+	struct lsmblob		oblob;
 	struct audit_cap_data	fcap;
 	unsigned int		fcap_ver;
 	unsigned char		type;		/* record type */
@@ -165,7 +165,7 @@ struct audit_context {
 			kuid_t			uid;
 			kgid_t			gid;
 			umode_t			mode;
-			u32			osid;
+			struct lsmblob		oblob;
 			int			has_perm;
 			uid_t			perm_uid;
 			gid_t			perm_gid;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 46d7a58babd2..04367c3593e4 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -646,17 +646,15 @@ static int audit_filter_rules(struct task_struct *tsk,
 			if (f->lsm_rule) {
 				/* Find files that match */
 				if (name) {
-					lsmblob_init(&blob, name->osid);
 					result = security_audit_rule_match(
-								&blob,
+								&name->oblob,
 								f->type,
 								f->op,
 								f->lsm_rule);
 				} else if (ctx) {
 					list_for_each_entry(n, &ctx->names_list, list) {
-						lsmblob_init(&blob, n->osid);
 						if (security_audit_rule_match(
-								&blob,
+								&n->oblob,
 								f->type,
 								f->op,
 								f->lsm_rule)) {
@@ -668,8 +666,7 @@ static int audit_filter_rules(struct task_struct *tsk,
 				/* Find ipc objects that match */
 				if (!ctx || ctx->type != AUDIT_IPC)
 					break;
-				lsmblob_init(&blob, ctx->ipc.osid);
-				if (security_audit_rule_match(&blob,
+				if (security_audit_rule_match(&ctx->ipc.oblob,
 							      f->type, f->op,
 							      f->lsm_rule))
 					++result;
@@ -937,13 +934,57 @@ static inline void audit_free_context(struct audit_context *context)
 	kfree(context);
 }
 
+static int audit_log_object_context(struct audit_buffer *ab,
+				    struct lsmblob *blob)
+{
+	struct lsmcontext context;
+	const char *lsm;
+	int i;
+
+	/*
+	 * None of the installed modules have object labels.
+	 */
+	if (security_lsm_slot_name(0) == NULL)
+		return 0;
+
+	if (blob->secid[0] != 0) {
+		if (security_secid_to_secctx(blob, &context, 0)) {
+			audit_log_format(ab, " obj=?");
+			return 1;
+		}
+		audit_log_format(ab, " obj=%s", context.context);
+		security_release_secctx(&context);
+	}
+
+	/*
+	 * Don't do anything more unless there is more than one LSM
+	 * with a security context to report.
+	 */
+	if (security_lsm_slot_name(1) == NULL)
+		return 0;
+
+	for (i = 0; i < LSMBLOB_ENTRIES; i++) {
+		lsm = security_lsm_slot_name(i);
+		if (lsm == NULL)
+			break;
+		if (blob->secid[i] == 0)
+			continue;
+		if (security_secid_to_secctx(blob, &context, i)) {
+			audit_log_format(ab, " obj_%s=?", lsm);
+			continue;
+		}
+		audit_log_format(ab, " obj_%s=%s", lsm, context.context);
+		security_release_secctx(&context);
+	}
+	return 0;
+}
+
 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 				 kuid_t auid, kuid_t uid,
 				 unsigned int sessionid,
 				 struct lsmblob *blob, char *comm)
 {
 	struct audit_buffer *ab;
-	struct lsmcontext lsmctx;
 	int rc = 0;
 
 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
@@ -953,15 +994,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
 			 from_kuid(&init_user_ns, auid),
 			 from_kuid(&init_user_ns, uid), sessionid);
-	if (lsmblob_is_set(blob)) {
-		if (security_secid_to_secctx(blob, &lsmctx, LSMBLOB_FIRST)) {
-			audit_log_format(ab, " obj=(none)");
-			rc = 1;
-		} else {
-			audit_log_format(ab, " obj=%s", lsmctx.context);
-			security_release_secctx(&lsmctx);
-		}
-	}
+	rc = audit_log_object_context(ab, blob);
 	audit_log_format(ab, " ocomm=");
 	audit_log_untrustedstring(ab, comm);
 	audit_log_end(ab);
@@ -1187,26 +1220,14 @@ static void show_special(struct audit_context *context, int *call_panic)
 				context->socketcall.args[i]);
 		break; }
 	case AUDIT_IPC: {
-		u32 osid = context->ipc.osid;
+		struct lsmblob *oblob = & context->ipc.oblob;
 
 		audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
 				 from_kuid(&init_user_ns, context->ipc.uid),
 				 from_kgid(&init_user_ns, context->ipc.gid),
 				 context->ipc.mode);
-		if (osid) {
-			struct lsmcontext lsmcxt;
-			struct lsmblob blob;
-
-			lsmblob_init(&blob, osid);
-			if (security_secid_to_secctx(&blob, &lsmcxt,
-						     LSMBLOB_FIRST)) {
-				audit_log_format(ab, " osid=%u", osid);
-				*call_panic = 1;
-			} else {
-				audit_log_format(ab, " obj=%s", lsmcxt.context);
-				security_release_secctx(&lsmcxt);
-			}
-		}
+		if (audit_log_object_context(ab, oblob))
+			*call_panic = 1;
 		if (context->ipc.has_perm) {
 			audit_log_end(ab);
 			ab = audit_log_start(context, GFP_KERNEL,
@@ -1347,20 +1368,8 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
 				 from_kgid(&init_user_ns, n->gid),
 				 MAJOR(n->rdev),
 				 MINOR(n->rdev));
-	if (n->osid != 0) {
-		struct lsmblob blob;
-		struct lsmcontext lsmctx;
-
-		lsmblob_init(&blob, n->osid);
-		if (security_secid_to_secctx(&blob, &lsmctx, LSMBLOB_FIRST)) {
-			audit_log_format(ab, " osid=%u", n->osid);
-			if (call_panic)
-				*call_panic = 2;
-		} else {
-			audit_log_format(ab, " obj=%s", lsmctx.context);
-			security_release_secctx(&lsmctx);
-		}
-	}
+	if (audit_log_object_context(ab, &n->oblob) && call_panic)
+		*call_panic = 2;
 
 	/* log the audit_names record type */
 	switch (n->type) {
@@ -1908,17 +1917,13 @@ static inline int audit_copy_fcaps(struct audit_names *name,
 void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
 		      struct inode *inode, unsigned int flags)
 {
-	struct lsmblob blob;
-
 	name->ino   = inode->i_ino;
 	name->dev   = inode->i_sb->s_dev;
 	name->mode  = inode->i_mode;
 	name->uid   = inode->i_uid;
 	name->gid   = inode->i_gid;
 	name->rdev  = inode->i_rdev;
-	security_inode_getsecid(inode, &blob);
-	/* scaffolding until osid is updated */
-	name->osid = blob.secid[0];
+	security_inode_getsecid(inode, &name->oblob);
 	if (flags & AUDIT_INODE_NOEVAL) {
 		name->fcap_ver = -1;
 		return;
@@ -2268,14 +2273,11 @@ void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
 {
 	struct audit_context *context = audit_context();
-	struct lsmblob blob;
 	context->ipc.uid = ipcp->uid;
 	context->ipc.gid = ipcp->gid;
 	context->ipc.mode = ipcp->mode;
 	context->ipc.has_perm = 0;
-	security_ipc_getsecid(ipcp, &blob);
-	/* scaffolding on the [0] - change "osid" to a lsmblob */
-	context->ipc.osid = blob.secid[0];
+	security_ipc_getsecid(ipcp, &context->ipc.oblob);
 	context->type = AUDIT_IPC;
 }
 
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 21/28] NET: Store LSM netlabel data in a lsmblob
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Netlabel uses LSM interfaces requiring an lsmblob and
the internal storage is used to pass information between
these interfaces, so change the internal data from a secid
to a lsmblob. Update the netlabel interfaces and their
callers to accommodate the change. This requires that the
modules using netlabel use the lsm_id.slot to access the
correct secid when using netlabel.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 include/net/netlabel.h              |  8 ++--
 net/ipv4/cipso_ipv4.c               |  6 ++-
 net/netlabel/netlabel_kapi.c        |  6 +--
 net/netlabel/netlabel_unlabeled.c   | 57 +++++++++++------------------
 net/netlabel/netlabel_unlabeled.h   |  2 +-
 security/selinux/hooks.c            |  2 +-
 security/selinux/include/security.h |  1 +
 security/selinux/netlabel.c         |  2 +-
 security/selinux/ss/services.c      |  4 +-
 security/smack/smack.h              |  1 +
 security/smack/smack_lsm.c          |  5 ++-
 security/smack/smackfs.c            | 10 +++--
 12 files changed, 50 insertions(+), 54 deletions(-)

diff --git a/include/net/netlabel.h b/include/net/netlabel.h
index 72d6435fc16c..6c550455e69f 100644
--- a/include/net/netlabel.h
+++ b/include/net/netlabel.h
@@ -180,7 +180,7 @@ struct netlbl_lsm_catmap {
  * @attr.mls: MLS sensitivity label
  * @attr.mls.cat: MLS category bitmap
  * @attr.mls.lvl: MLS sensitivity level
- * @attr.secid: LSM specific secid token
+ * @attr.lsmblob: LSM specific data
  *
  * Description:
  * This structure is used to pass security attributes between NetLabel and the
@@ -215,7 +215,7 @@ struct netlbl_lsm_secattr {
 			struct netlbl_lsm_catmap *cat;
 			u32 lvl;
 		} mls;
-		u32 secid;
+		struct lsmblob lsmblob;
 	} attr;
 };
 
@@ -429,7 +429,7 @@ int netlbl_cfg_unlbl_static_add(struct net *net,
 				const void *addr,
 				const void *mask,
 				u16 family,
-				u32 secid,
+				struct lsmblob *lsmblob,
 				struct netlbl_audit *audit_info);
 int netlbl_cfg_unlbl_static_del(struct net *net,
 				const char *dev_name,
@@ -537,7 +537,7 @@ static inline int netlbl_cfg_unlbl_static_add(struct net *net,
 					      const void *addr,
 					      const void *mask,
 					      u16 family,
-					      u32 secid,
+					      struct lsmblob *lsmblob,
 					      struct netlbl_audit *audit_info)
 {
 	return -ENOSYS;
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index f0165c5f376b..eb4939f38a14 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -1481,7 +1481,8 @@ static int cipso_v4_gentag_loc(const struct cipso_v4_doi *doi_def,
 
 	buffer[0] = CIPSO_V4_TAG_LOCAL;
 	buffer[1] = CIPSO_V4_TAG_LOC_BLEN;
-	*(u32 *)&buffer[2] = secattr->attr.secid;
+	/* only one netlabel user - the first */
+	*(u32 *)&buffer[2] = secattr->attr.lsmblob.secid[0];
 
 	return CIPSO_V4_TAG_LOC_BLEN;
 }
@@ -1501,7 +1502,8 @@ static int cipso_v4_parsetag_loc(const struct cipso_v4_doi *doi_def,
 				 const unsigned char *tag,
 				 struct netlbl_lsm_secattr *secattr)
 {
-	secattr->attr.secid = *(u32 *)&tag[2];
+	/* only one netlabel user - the first */
+	secattr->attr.lsmblob.secid[0] = *(u32 *)&tag[2];
 	secattr->flags |= NETLBL_SECATTR_SECID;
 
 	return 0;
diff --git a/net/netlabel/netlabel_kapi.c b/net/netlabel/netlabel_kapi.c
index ee3e5b6471a6..724d44943543 100644
--- a/net/netlabel/netlabel_kapi.c
+++ b/net/netlabel/netlabel_kapi.c
@@ -210,7 +210,7 @@ int netlbl_cfg_unlbl_map_add(const char *domain,
  * @addr: IP address in network byte order (struct in[6]_addr)
  * @mask: address mask in network byte order (struct in[6]_addr)
  * @family: address family
- * @secid: LSM secid value for the entry
+ * @lsmblob: LSM data value for the entry
  * @audit_info: NetLabel audit information
  *
  * Description:
@@ -224,7 +224,7 @@ int netlbl_cfg_unlbl_static_add(struct net *net,
 				const void *addr,
 				const void *mask,
 				u16 family,
-				u32 secid,
+				struct lsmblob *lsmblob,
 				struct netlbl_audit *audit_info)
 {
 	u32 addr_len;
@@ -244,7 +244,7 @@ int netlbl_cfg_unlbl_static_add(struct net *net,
 
 	return netlbl_unlhsh_add(net,
 				 dev_name, addr, mask, addr_len,
-				 secid, audit_info);
+				 lsmblob, audit_info);
 }
 
 /**
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 4716e0011ba5..57ede7781c8f 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -80,7 +80,7 @@ struct netlbl_unlhsh_tbl {
 #define netlbl_unlhsh_addr4_entry(iter) \
 	container_of(iter, struct netlbl_unlhsh_addr4, list)
 struct netlbl_unlhsh_addr4 {
-	u32 secid;
+	struct lsmblob lsmblob;
 
 	struct netlbl_af4list list;
 	struct rcu_head rcu;
@@ -88,7 +88,7 @@ struct netlbl_unlhsh_addr4 {
 #define netlbl_unlhsh_addr6_entry(iter) \
 	container_of(iter, struct netlbl_unlhsh_addr6, list)
 struct netlbl_unlhsh_addr6 {
-	u32 secid;
+	struct lsmblob lsmblob;
 
 	struct netlbl_af6list list;
 	struct rcu_head rcu;
@@ -233,7 +233,7 @@ static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex)
  * @iface: the associated interface entry
  * @addr: IPv4 address in network byte order
  * @mask: IPv4 address mask in network byte order
- * @secid: LSM secid value for entry
+ * @lsmblob: LSM data value for entry
  *
  * Description:
  * Add a new address entry into the unlabeled connection hash table using the
@@ -244,7 +244,7 @@ static struct netlbl_unlhsh_iface *netlbl_unlhsh_search_iface(int ifindex)
 static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
 				   const struct in_addr *addr,
 				   const struct in_addr *mask,
-				   u32 secid)
+				   struct lsmblob *lsmblob)
 {
 	int ret_val;
 	struct netlbl_unlhsh_addr4 *entry;
@@ -256,7 +256,7 @@ static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
 	entry->list.addr = addr->s_addr & mask->s_addr;
 	entry->list.mask = mask->s_addr;
 	entry->list.valid = 1;
-	entry->secid = secid;
+	entry->lsmblob = *lsmblob;
 
 	spin_lock(&netlbl_unlhsh_lock);
 	ret_val = netlbl_af4list_add(&entry->list, &iface->addr4_list);
@@ -273,7 +273,7 @@ static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
  * @iface: the associated interface entry
  * @addr: IPv6 address in network byte order
  * @mask: IPv6 address mask in network byte order
- * @secid: LSM secid value for entry
+ * @lsmblob: LSM data value for entry
  *
  * Description:
  * Add a new address entry into the unlabeled connection hash table using the
@@ -284,7 +284,7 @@ static int netlbl_unlhsh_add_addr4(struct netlbl_unlhsh_iface *iface,
 static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface,
 				   const struct in6_addr *addr,
 				   const struct in6_addr *mask,
-				   u32 secid)
+				   struct lsmblob *lsmblob)
 {
 	int ret_val;
 	struct netlbl_unlhsh_addr6 *entry;
@@ -300,7 +300,7 @@ static int netlbl_unlhsh_add_addr6(struct netlbl_unlhsh_iface *iface,
 	entry->list.addr.s6_addr32[3] &= mask->s6_addr32[3];
 	entry->list.mask = *mask;
 	entry->list.valid = 1;
-	entry->secid = secid;
+	entry->lsmblob = *lsmblob;
 
 	spin_lock(&netlbl_unlhsh_lock);
 	ret_val = netlbl_af6list_add(&entry->list, &iface->addr6_list);
@@ -379,7 +379,7 @@ int netlbl_unlhsh_add(struct net *net,
 		      const void *addr,
 		      const void *mask,
 		      u32 addr_len,
-		      u32 secid,
+		      struct lsmblob *lsmblob,
 		      struct netlbl_audit *audit_info)
 {
 	int ret_val;
@@ -388,7 +388,6 @@ int netlbl_unlhsh_add(struct net *net,
 	struct netlbl_unlhsh_iface *iface;
 	struct audit_buffer *audit_buf = NULL;
 	struct lsmcontext context;
-	struct lsmblob blob;
 
 	if (addr_len != sizeof(struct in_addr) &&
 	    addr_len != sizeof(struct in6_addr))
@@ -421,7 +420,7 @@ int netlbl_unlhsh_add(struct net *net,
 		const struct in_addr *addr4 = addr;
 		const struct in_addr *mask4 = mask;
 
-		ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, secid);
+		ret_val = netlbl_unlhsh_add_addr4(iface, addr4, mask4, lsmblob);
 		if (audit_buf != NULL)
 			netlbl_af4list_audit_addr(audit_buf, 1,
 						  dev_name,
@@ -434,7 +433,7 @@ int netlbl_unlhsh_add(struct net *net,
 		const struct in6_addr *addr6 = addr;
 		const struct in6_addr *mask6 = mask;
 
-		ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, secid);
+		ret_val = netlbl_unlhsh_add_addr6(iface, addr6, mask6, lsmblob);
 		if (audit_buf != NULL)
 			netlbl_af6list_audit_addr(audit_buf, 1,
 						  dev_name,
@@ -451,8 +450,7 @@ int netlbl_unlhsh_add(struct net *net,
 unlhsh_add_return:
 	rcu_read_unlock();
 	if (audit_buf != NULL) {
-		lsmblob_init(&blob, secid);
-		if (security_secid_to_secctx(&blob, &context) == 0) {
+		if (security_secid_to_secctx(lsmblob, &context) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s",
 					 context.context);
 			security_release_secctx(&context);
@@ -487,7 +485,6 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
 	struct audit_buffer *audit_buf;
 	struct net_device *dev;
 	struct lsmcontext context;
-	struct lsmblob blob;
 
 	spin_lock(&netlbl_unlhsh_lock);
 	list_entry = netlbl_af4list_remove(addr->s_addr, mask->s_addr,
@@ -507,10 +504,8 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
 					  addr->s_addr, mask->s_addr);
 		if (dev != NULL)
 			dev_put(dev);
-		if (entry != NULL)
-			lsmblob_init(&blob, entry->secid);
 		if (entry != NULL &&
-		    security_secid_to_secctx(&blob, &context) == 0) {
+		    security_secid_to_secctx(&entry->lsmblob, &context) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s",
 					 context.context);
 			security_release_secctx(&context);
@@ -551,7 +546,6 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
 	struct audit_buffer *audit_buf;
 	struct net_device *dev;
 	struct lsmcontext context;
-	struct lsmblob blob;
 
 	spin_lock(&netlbl_unlhsh_lock);
 	list_entry = netlbl_af6list_remove(addr, mask, &iface->addr6_list);
@@ -570,10 +564,8 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
 					  addr, mask);
 		if (dev != NULL)
 			dev_put(dev);
-		if (entry != NULL)
-			lsmblob_init(&blob, entry->secid);
 		if (entry != NULL &&
-		    security_secid_to_secctx(&blob, &context) == 0) {
+		    security_secid_to_secctx(&entry->lsmblob, &context) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s",
 					 context.context);
 			security_release_secctx(&context);
@@ -927,9 +919,8 @@ static int netlbl_unlabel_staticadd(struct sk_buff *skb,
 	if (ret_val != 0)
 		return ret_val;
 
-	/* scaffolding with the [0] */
 	return netlbl_unlhsh_add(&init_net,
-				 dev_name, addr, mask, addr_len, blob.secid[0],
+				 dev_name, addr, mask, addr_len, &blob,
 				 &audit_info);
 }
 
@@ -977,10 +968,8 @@ static int netlbl_unlabel_staticadddef(struct sk_buff *skb,
 	if (ret_val != 0)
 		return ret_val;
 
-	/* scaffolding with the [0] */
 	return netlbl_unlhsh_add(&init_net,
-				 NULL, addr, mask, addr_len, blob.secid[0],
-				 &audit_info);
+				 NULL, addr, mask, addr_len, &blob, &audit_info);
 }
 
 /**
@@ -1092,8 +1081,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
 	struct net_device *dev;
 	struct lsmcontext context;
 	void *data;
-	u32 secid;
-	struct lsmblob blob;
+	struct lsmblob *lsmb;
 
 	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
 			   cb_arg->seq, &netlbl_unlabel_gnl_family,
@@ -1131,7 +1119,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
 		if (ret_val != 0)
 			goto list_cb_failure;
 
-		secid = addr4->secid;
+		lsmb = (struct lsmblob *)&addr4->lsmblob;
 	} else {
 		ret_val = nla_put_in6_addr(cb_arg->skb,
 					   NLBL_UNLABEL_A_IPV6ADDR,
@@ -1145,11 +1133,10 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
 		if (ret_val != 0)
 			goto list_cb_failure;
 
-		secid = addr6->secid;
+		lsmb = (struct lsmblob *)&addr6->lsmblob;
 	}
 
-	lsmblob_init(&blob, secid);
-	ret_val = security_secid_to_secctx(&blob, &context);
+	ret_val = security_secid_to_secctx(lsmb, &context);
 	if (ret_val != 0)
 		goto list_cb_failure;
 	ret_val = nla_put(cb_arg->skb,
@@ -1500,7 +1487,7 @@ int netlbl_unlabel_getattr(const struct sk_buff *skb,
 					      &iface->addr4_list);
 		if (addr4 == NULL)
 			goto unlabel_getattr_nolabel;
-		secattr->attr.secid = netlbl_unlhsh_addr4_entry(addr4)->secid;
+		secattr->attr.lsmblob = netlbl_unlhsh_addr4_entry(addr4)->lsmblob;
 		break;
 	}
 #if IS_ENABLED(CONFIG_IPV6)
@@ -1513,7 +1500,7 @@ int netlbl_unlabel_getattr(const struct sk_buff *skb,
 					      &iface->addr6_list);
 		if (addr6 == NULL)
 			goto unlabel_getattr_nolabel;
-		secattr->attr.secid = netlbl_unlhsh_addr6_entry(addr6)->secid;
+		secattr->attr.lsmblob = netlbl_unlhsh_addr6_entry(addr6)->lsmblob;
 		break;
 	}
 #endif /* IPv6 */
diff --git a/net/netlabel/netlabel_unlabeled.h b/net/netlabel/netlabel_unlabeled.h
index 3a9e5dc9511b..dcff99695c97 100644
--- a/net/netlabel/netlabel_unlabeled.h
+++ b/net/netlabel/netlabel_unlabeled.h
@@ -225,7 +225,7 @@ int netlbl_unlhsh_add(struct net *net,
 		      const void *addr,
 		      const void *mask,
 		      u32 addr_len,
-		      u32 secid,
+		      struct lsmblob *lsmblob,
 		      struct netlbl_audit *audit_info);
 int netlbl_unlhsh_remove(struct net *net,
 			 const char *dev_name,
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 74c491980ed2..352be16a887d 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -6622,7 +6622,7 @@ struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
 	.lbs_superblock = sizeof(struct superblock_security_struct),
 };
 
-static struct lsm_id selinux_lsmid __lsm_ro_after_init = {
+struct lsm_id selinux_lsmid __lsm_ro_after_init = {
 	.lsm  = "selinux",
 	.slot = LSMBLOB_NEEDED
 };
diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index b5b7c5aade8c..f0ca3879ba48 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -68,6 +68,7 @@
 struct netlbl_lsm_secattr;
 
 extern int selinux_enabled;
+extern struct lsm_id selinux_lsmid;
 
 /* Policy capabilities */
 enum {
diff --git a/security/selinux/netlabel.c b/security/selinux/netlabel.c
index c40914a157b7..120d50c1bcac 100644
--- a/security/selinux/netlabel.c
+++ b/security/selinux/netlabel.c
@@ -122,7 +122,7 @@ static struct netlbl_lsm_secattr *selinux_netlbl_sock_getattr(
 		return NULL;
 
 	if ((secattr->flags & NETLBL_SECATTR_SECID) &&
-	    (secattr->attr.secid == sid))
+	    (secattr->attr.lsmblob.secid[selinux_lsmid.slot] == sid))
 		return secattr;
 
 	return NULL;
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index e3f5d6aece66..4ca0e006c3cc 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -3593,7 +3593,7 @@ int security_netlbl_secattr_to_sid(struct selinux_state *state,
 	if (secattr->flags & NETLBL_SECATTR_CACHE)
 		*sid = *(u32 *)secattr->cache->data;
 	else if (secattr->flags & NETLBL_SECATTR_SECID)
-		*sid = secattr->attr.secid;
+		*sid = secattr->attr.lsmblob.secid[selinux_lsmid.slot];
 	else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
 		rc = -EIDRM;
 		ctx = sidtab_search(sidtab, SECINITSID_NETMSG);
@@ -3666,7 +3666,7 @@ int security_netlbl_sid_to_secattr(struct selinux_state *state,
 	if (secattr->domain == NULL)
 		goto out;
 
-	secattr->attr.secid = sid;
+	secattr->attr.lsmblob.secid[selinux_lsmid.slot] = sid;
 	secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
 	mls_export_netlbl_lvl(policydb, ctx, secattr);
 	rc = mls_export_netlbl_cat(policydb, ctx, secattr);
diff --git a/security/smack/smack.h b/security/smack/smack.h
index 7cc3a3382fee..039bf5de56b4 100644
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -320,6 +320,7 @@ void smk_destroy_label_list(struct list_head *list);
  * Shared data.
  */
 extern int smack_enabled;
+extern struct lsm_id smack_lsmid;
 extern int smack_cipso_direct;
 extern int smack_cipso_mapped;
 extern struct smack_known *smack_net_ambient;
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 472cb2097d36..7a30b8692b1e 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -3741,7 +3741,8 @@ static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap,
 		/*
 		 * Looks like a fallback, which gives us a secid.
 		 */
-		return smack_from_secid(sap->attr.secid);
+		return smack_from_secid(
+				sap->attr.lsmblob.secid[smack_lsmid.slot]);
 	/*
 	 * Without guidance regarding the smack value
 	 * for the packet fall back on the network
@@ -4558,7 +4559,7 @@ struct lsm_blob_sizes smack_blob_sizes __lsm_ro_after_init = {
 	.lbs_superblock = sizeof(struct superblock_smack),
 };
 
-static struct lsm_id smack_lsmid __lsm_ro_after_init = {
+struct lsm_id smack_lsmid __lsm_ro_after_init = {
 	.lsm  = "smack",
 	.slot = LSMBLOB_NEEDED
 };
diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
index faf2ea3968b3..6a4c468c200c 100644
--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -1150,6 +1150,7 @@ static void smk_net4addr_insert(struct smk_net4addr *new)
 static ssize_t smk_write_net4addr(struct file *file, const char __user *buf,
 				size_t count, loff_t *ppos)
 {
+	struct lsmblob lsmblob;
 	struct smk_net4addr *snp;
 	struct sockaddr_in newname;
 	char *smack;
@@ -1281,10 +1282,13 @@ static ssize_t smk_write_net4addr(struct file *file, const char __user *buf,
 	 * this host so that incoming packets get labeled.
 	 * but only if we didn't get the special CIPSO option
 	 */
-	if (rc == 0 && skp != NULL)
+	if (rc == 0 && skp != NULL) {
+		lsmblob_init(&lsmblob, 0);
+		lsmblob.secid[smack_lsmid.slot] = snp->smk_label->smk_secid;
 		rc = netlbl_cfg_unlbl_static_add(&init_net, NULL,
-			&snp->smk_host, &snp->smk_mask, PF_INET,
-			snp->smk_label->smk_secid, &audit_info);
+			&snp->smk_host, &snp->smk_mask, PF_INET, &lsmblob,
+			&audit_info);
+	}
 
 	if (rc == 0)
 		rc = count;
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 20/28] LSM: security_secid_to_secctx in netlink netfilter
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Change netlink netfilter interfaces to use lsmcontext
pointers, and remove scaffolding.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 net/netfilter/nfnetlink_queue.c | 32 +++++++++++++-------------------
 1 file changed, 13 insertions(+), 19 deletions(-)

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 5593ee05d106..58d5bd7a376e 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -305,12 +305,10 @@ static int nfqnl_put_sk_uidgid(struct sk_buff *skb, struct sock *sk)
 	return -1;
 }
 
-static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
+static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, struct lsmcontext *context)
 {
-	u32 seclen = 0;
 #if IS_ENABLED(CONFIG_NETWORK_SECMARK)
 	struct lsmblob blob;
-	struct lsmcontext context = { };
 
 	if (!skb || !sk_fullsock(skb->sk))
 		return 0;
@@ -318,15 +316,16 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
 	read_lock_bh(&skb->sk->sk_callback_lock);
 
 	if (skb->secmark) {
+		/* Any LSM might be looking for the secmark */
 		lsmblob_init(&blob, skb->secmark);
-		security_secid_to_secctx(&blob, &context);
-		*secdata = context.context;
+		security_secid_to_secctx(&blob, context);
 	}
 
 	read_unlock_bh(&skb->sk->sk_callback_lock);
-	seclen = context.len;
+	return context->len;
+#else
+	return 0;
 #endif
-	return seclen;
 }
 
 static u32 nfqnl_get_bridge_size(struct nf_queue_entry *entry)
@@ -402,8 +401,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	enum ip_conntrack_info uninitialized_var(ctinfo);
 	struct nfnl_ct_hook *nfnl_ct;
 	bool csum_verify;
-	struct lsmcontext scaff; /* scaffolding */
-	char *secdata = NULL;
+	struct lsmcontext context = { };
 	u32 seclen = 0;
 
 	size =    nlmsg_total_size(sizeof(struct nfgenmsg))
@@ -470,7 +468,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	}
 
 	if ((queue->flags & NFQA_CFG_F_SECCTX) && entskb->sk) {
-		seclen = nfqnl_get_sk_secctx(entskb, &secdata);
+		seclen = nfqnl_get_sk_secctx(entskb, &context);
 		if (seclen)
 			size += nla_total_size(seclen);
 	}
@@ -605,7 +603,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	    nfqnl_put_sk_uidgid(skb, entskb->sk) < 0)
 		goto nla_put_failure;
 
-	if (seclen && nla_put(skb, NFQA_SECCTX, seclen, secdata))
+	if (seclen && nla_put(skb, NFQA_SECCTX, context.len, context.context))
 		goto nla_put_failure;
 
 	if (ct && nfnl_ct->build(skb, ct, ctinfo, NFQA_CT, NFQA_CT_INFO) < 0)
@@ -633,10 +631,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	}
 
 	nlh->nlmsg_len = skb->len;
-	if (seclen) {
-		lsmcontext_init(&scaff, secdata, seclen, 0);
-		security_release_secctx(&scaff);
-	}
+	if (seclen)
+		security_release_secctx(&context);
 	return skb;
 
 nla_put_failure:
@@ -644,10 +640,8 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	kfree_skb(skb);
 	net_err_ratelimited("nf_queue: error creating packet message\n");
 nlmsg_failure:
-	if (seclen) {
-		lsmcontext_init(&scaff, secdata, seclen, 0);
-		security_release_secctx(&scaff);
-	}
+	if (seclen)
+		security_release_secctx(&context);
 	return NULL;
 }
 
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 22/28] SELinux: Verify LSM display sanity in binder
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Verify that the tasks on the ends of a binder transaction
use LSM display values that don't cause SELinux contexts
to be interpreted by another LSM or another LSM's context
to be interpreted by SELinux. No judgement is made in cases
that where SELinux contexts are not used in the binder
transaction.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 include/linux/security.h |  1 +
 security/selinux/hooks.c | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+)

diff --git a/include/linux/security.h b/include/linux/security.h
index c16aea55be97..7fcc94ec8e04 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -125,6 +125,7 @@ struct lsmblob {
 	u32     secid[LSMBLOB_ENTRIES];
 };
 
+#define LSMBLOB_FIRST		0	/* First valid LSM slot number */
 #define LSMBLOB_INVALID		-1	/* Not a valid LSM slot number */
 #define LSMBLOB_NEEDED		-2	/* Slot requested on initialization */
 #define LSMBLOB_NOT_NEEDED	-3	/* Slot not requested */
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 352be16a887d..2844f2ab7706 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2009,6 +2009,28 @@ static inline u32 open_file_to_av(struct file *file)
 	return av;
 }
 
+/*
+ * Verify that if the "display" LSM is SELinux for either task
+ * that it is for both tasks.
+ */
+static inline bool compatible_task_displays(struct task_struct *here,
+					    struct task_struct *there)
+{
+	int h = lsm_task_display(here);
+	int t = lsm_task_display(there);
+
+	if (h == t)
+		return true;
+
+	/* unspecified is only ok if SELinux isn't going to be involved */
+	if (selinux_lsmid.slot == LSMBLOB_FIRST)
+		return ((h == LSMBLOB_FIRST && t == LSMBLOB_INVALID) ||
+			(t == LSMBLOB_FIRST && h == LSMBLOB_INVALID));
+
+	/* it's ok only if neither display is SELinux */
+	return (h != selinux_lsmid.slot && t != selinux_lsmid.slot);
+}
+
 /* Hook functions begin here. */
 
 static int selinux_binder_set_context_mgr(struct task_struct *mgr)
@@ -2016,6 +2038,9 @@ static int selinux_binder_set_context_mgr(struct task_struct *mgr)
 	u32 mysid = current_sid();
 	u32 mgrsid = task_sid(mgr);
 
+	if (!compatible_task_displays(current, mgr))
+		return -EINVAL;
+
 	return avc_has_perm(&selinux_state,
 			    mysid, mgrsid, SECCLASS_BINDER,
 			    BINDER__SET_CONTEXT_MGR, NULL);
@@ -2029,6 +2054,9 @@ static int selinux_binder_transaction(struct task_struct *from,
 	u32 tosid = task_sid(to);
 	int rc;
 
+	if (!compatible_task_displays(from, to))
+		return -EINVAL;
+
 	if (mysid != fromsid) {
 		rc = avc_has_perm(&selinux_state,
 				  mysid, fromsid, SECCLASS_BINDER,
@@ -2048,6 +2076,9 @@ static int selinux_binder_transfer_binder(struct task_struct *from,
 	u32 fromsid = task_sid(from);
 	u32 tosid = task_sid(to);
 
+	if (!compatible_task_displays(from, to))
+		return -EINVAL;
+
 	return avc_has_perm(&selinux_state,
 			    fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
 			    NULL);
@@ -2064,6 +2095,9 @@ static int selinux_binder_transfer_file(struct task_struct *from,
 	struct common_audit_data ad;
 	int rc;
 
+	if (!compatible_task_displays(from, to))
+		return -EINVAL;
+
 	ad.type = LSM_AUDIT_DATA_PATH;
 	ad.u.path = file->f_path;
 
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 19/28] LSM: Use lsmcontext in security_inode_getsecctx
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Change the security_inode_getsecctx() interface to fill
a lsmcontext structure instead of data and length pointers.
This provides the information about which LSM created the
context so that security_release_secctx() can use the
correct hook. A lsmcontext is used within kernfs to store
the security information as well.

security_inode_getsecctx() does not use the "display"
value. There's only one possible user at any time at
this point, and the use is only internal.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 fs/kernfs/dir.c             |  9 ++-------
 fs/kernfs/inode.c           | 34 ++++++++++++----------------------
 fs/kernfs/kernfs-internal.h |  3 +--
 fs/nfsd/nfs4xdr.c           | 23 +++++++++--------------
 include/linux/security.h    |  5 +++--
 security/security.c         | 13 +++++++++++--
 6 files changed, 38 insertions(+), 49 deletions(-)

diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index c8362b6d556e..1d000289d8b7 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -532,13 +532,8 @@ void kernfs_put(struct kernfs_node *kn)
 	kfree_const(kn->name);
 
 	if (kn->iattr) {
-		struct lsmcontext scaff; /* scaffolding */
-
-		if (kn->iattr->ia_secdata) {
-			lsmcontext_init(&scaff, kn->iattr->ia_secdata,
-					kn->iattr->ia_secdata_len, 0);
-			security_release_secctx(&scaff);
-		}
+		if (kn->iattr->ia_context.context)
+			security_release_secctx(&kn->iattr->ia_context);
 		simple_xattrs_free(&kn->iattr->xattrs);
 		kmem_cache_free(kernfs_iattrs_cache, kn->iattr);
 	}
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index 02cde9dac5ee..ffbf7863306d 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -135,21 +135,14 @@ int kernfs_iop_setattr(struct dentry *dentry, struct iattr *iattr)
 	return error;
 }
 
-static int kernfs_node_setsecdata(struct kernfs_iattrs *attrs, void **secdata,
-				  u32 *secdata_len)
+static void kernfs_node_setsecdata(struct kernfs_iattrs *attrs,
+				   struct lsmcontext *cp)
 {
-	void *old_secdata;
-	size_t old_secdata_len;
+	struct lsmcontext old_context;
 
-	old_secdata = attrs->ia_secdata;
-	old_secdata_len = attrs->ia_secdata_len;
-
-	attrs->ia_secdata = *secdata;
-	attrs->ia_secdata_len = *secdata_len;
-
-	*secdata = old_secdata;
-	*secdata_len = old_secdata_len;
-	return 0;
+	old_context = attrs->ia_context;
+	attrs->ia_context = *cp;
+	*cp = old_context;
 }
 
 ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size)
@@ -192,8 +185,8 @@ static void kernfs_refresh_inode(struct kernfs_node *kn, struct inode *inode)
 		 * persistent copy in kernfs_node.
 		 */
 		set_inode_attr(inode, &attrs->ia_iattr);
-		security_inode_notifysecctx(inode, attrs->ia_secdata,
-					    attrs->ia_secdata_len);
+		security_inode_notifysecctx(inode, attrs->ia_context.context,
+					    attrs->ia_context.len);
 	}
 
 	if (kernfs_type(kn) == KERNFS_DIR)
@@ -350,8 +343,6 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler,
 	struct kernfs_node *kn = inode->i_private;
 	struct kernfs_iattrs *attrs;
 	struct lsmcontext context;
-	void *secdata;
-	u32 secdata_len = 0;
 	int error;
 
 	attrs = kernfs_iattrs(kn);
@@ -361,18 +352,17 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler,
 	error = security_inode_setsecurity(inode, suffix, value, size, flags);
 	if (error)
 		return error;
-	error = security_inode_getsecctx(inode, &secdata, &secdata_len);
+	error = security_inode_getsecctx(inode, &context);
 	if (error)
 		return error;
 
 	mutex_lock(&kernfs_mutex);
-	error = kernfs_node_setsecdata(attrs, &secdata, &secdata_len);
+	kernfs_node_setsecdata(attrs, &context);
 	mutex_unlock(&kernfs_mutex);
 
-	if (secdata) {
-		lsmcontext_init(&context, secdata, secdata_len, 0);
+	if (context.context)
 		security_release_secctx(&context);
-	}
+
 	return error;
 }
 
diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index 0b7d197a904c..844a028d282f 100644
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -21,8 +21,7 @@
 
 struct kernfs_iattrs {
 	struct iattr		ia_iattr;
-	void			*ia_secdata;
-	u32			ia_secdata_len;
+	struct lsmcontext	ia_context;
 
 	struct simple_xattrs	xattrs;
 };
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index bb3db033e144..d2dbec9c3340 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2304,11 +2304,11 @@ nfsd4_encode_layout_types(struct xdr_stream *xdr, u32 layout_types)
 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
 static inline __be32
 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
-			    void *context, int len)
+			    struct lsmcontext *context)
 {
 	__be32 *p;
 
-	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
+	p = xdr_reserve_space(xdr, context->len + 4 + 4 + 4);
 	if (!p)
 		return nfserr_resource;
 
@@ -2318,13 +2318,13 @@ nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
 	 */
 	*p++ = cpu_to_be32(0); /* lfs */
 	*p++ = cpu_to_be32(0); /* pi */
-	p = xdr_encode_opaque(p, context, len);
+	p = xdr_encode_opaque(p, context->context, context->len);
 	return 0;
 }
 #else
 static inline __be32
 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
-			    void *context, int len)
+			    struct lsmcontext *context)
 { return 0; }
 #endif
 
@@ -2420,9 +2420,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
 	__be32 status;
 	int err;
 	struct nfs4_acl *acl = NULL;
-	struct lsmcontext scaff; /* scaffolding */
-	void *context = NULL;
-	int contextlen;
+	struct lsmcontext context = { };
 	bool contextsupport = false;
 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
 	u32 minorversion = resp->cstate.minorversion;
@@ -2479,7 +2477,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
 		if (exp->ex_flags & NFSEXP_SECURITY_LABEL)
 			err = security_inode_getsecctx(d_inode(dentry),
-						&context, &contextlen);
+						       &context);
 		else
 			err = -EOPNOTSUPP;
 		contextsupport = (err == 0);
@@ -2908,8 +2906,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
 	}
 
 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
-		status = nfsd4_encode_security_label(xdr, rqstp, context,
-								contextlen);
+		status = nfsd4_encode_security_label(xdr, rqstp, &context);
 		if (status)
 			goto out;
 	}
@@ -2920,10 +2917,8 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
 
 out:
 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
-	if (context) {
-		lsmcontext_init(&scaff, context, contextlen, 0); /*scaffolding*/
-		security_release_secctx(&scaff);
-	}
+	if (context.context)
+		security_release_secctx(&context);
 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
 	kfree(acl);
 	if (tempfh) {
diff --git a/include/linux/security.h b/include/linux/security.h
index 2674eb70c2d7..c16aea55be97 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -489,7 +489,7 @@ void security_release_secctx(struct lsmcontext *cp);
 void security_inode_invalidate_secctx(struct inode *inode);
 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen);
 int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen);
-int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen);
+int security_inode_getsecctx(struct inode *inode, struct lsmcontext *cp);
 #else /* CONFIG_SECURITY */
 
 static inline int call_lsm_notifier(enum lsm_event event, void *data)
@@ -1290,7 +1290,8 @@ static inline int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32
 {
 	return -EOPNOTSUPP;
 }
-static inline int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
+static inline int security_inode_getsecctx(struct inode *inode,
+					   struct lsmcontext *cp)
 {
 	return -EOPNOTSUPP;
 }
diff --git a/security/security.c b/security/security.c
index 7bbc17cc212d..20805ad99ccd 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2198,9 +2198,18 @@ int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
 }
 EXPORT_SYMBOL(security_inode_setsecctx);
 
-int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
+int security_inode_getsecctx(struct inode *inode, struct lsmcontext *cp)
 {
-	return call_int_hook(inode_getsecctx, -EOPNOTSUPP, inode, ctx, ctxlen);
+	struct security_hook_list *hp;
+
+	memset(cp, 0, sizeof(*cp));
+
+	hlist_for_each_entry(hp, &security_hook_heads.inode_getsecctx, list) {
+		cp->slot = hp->lsmid->slot;
+		return hp->hook.inode_getsecctx(inode, (void **)&cp->context,
+						&cp->len);
+	}
+	return -EOPNOTSUPP;
 }
 EXPORT_SYMBOL(security_inode_getsecctx);
 
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 18/28] LSM: Use lsmcontext in security_dentry_init_security
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Change the security_dentry_init_security() interface to
fill an lsmcontext structure instead of a void * data area
and a length. The lone caller of this interface is NFS4,
which may make copies of the data using its own mechanisms.
A rework of the nfs4 code to use the lsmcontext properly
is a significant project, so the coward's way out is taken,
and the lsmcontext data from security_dentry_init_security()
is copied, then released directly.

This interface does not use the "display". There is currently
not case where that is useful or reasonable.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 fs/nfs/nfs4proc.c        | 26 ++++++++++++++++----------
 include/linux/security.h |  7 +++----
 security/security.c      | 29 +++++++++++++++++++++++++----
 3 files changed, 44 insertions(+), 18 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index af1c0db29c39..952f805965bb 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -113,6 +113,7 @@ static inline struct nfs4_label *
 nfs4_label_init_security(struct inode *dir, struct dentry *dentry,
 	struct iattr *sattr, struct nfs4_label *label)
 {
+	struct lsmcontext context;
 	int err;
 
 	if (label == NULL)
@@ -122,21 +123,26 @@ nfs4_label_init_security(struct inode *dir, struct dentry *dentry,
 		return NULL;
 
 	err = security_dentry_init_security(dentry, sattr->ia_mode,
-				&dentry->d_name, (void **)&label->label, &label->len);
-	if (err == 0)
-		return label;
+					    &dentry->d_name, &context);
+
+	if (err)
+		return NULL;
+
+	label->label = kmemdup(context.context, context.len, GFP_KERNEL);
+	if (label->label == NULL)
+		label = NULL;
+	else
+		label->len = context.len;
+
+	security_release_secctx(&context);
+
+	return label;
 
-	return NULL;
 }
 static inline void
 nfs4_label_release_security(struct nfs4_label *label)
 {
-	struct lsmcontext scaff; /* scaffolding */
-
-	if (label) {
-		lsmcontext_init(&scaff, label->label, label->len, 0);
-		security_release_secctx(&scaff);
-	}
+	kfree(label->label);
 }
 static inline u32 *nfs4_bitmask(struct nfs_server *server, struct nfs4_label *label)
 {
diff --git a/include/linux/security.h b/include/linux/security.h
index 7255825aa697..2674eb70c2d7 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -352,8 +352,8 @@ int security_sb_clone_mnt_opts(const struct super_block *oldsb,
 int security_add_mnt_opt(const char *option, const char *val,
 				int len, void **mnt_opts);
 int security_dentry_init_security(struct dentry *dentry, int mode,
-					const struct qstr *name, void **ctx,
-					u32 *ctxlen);
+					const struct qstr *name,
+					struct lsmcontext *ctx);
 int security_dentry_create_files_as(struct dentry *dentry, int mode,
 					struct qstr *name,
 					const struct cred *old,
@@ -724,8 +724,7 @@ static inline void security_inode_free(struct inode *inode)
 static inline int security_dentry_init_security(struct dentry *dentry,
 						 int mode,
 						 const struct qstr *name,
-						 void **ctx,
-						 u32 *ctxlen)
+						 struct lsmcontext *ctx)
 {
 	return -EOPNOTSUPP;
 }
diff --git a/security/security.c b/security/security.c
index 38e10f92dae3..7bbc17cc212d 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1029,12 +1029,33 @@ void security_inode_free(struct inode *inode)
 				inode_free_by_rcu);
 }
 
+/*
+ * security_dentry_init_security - initial context for a dentry
+ * @dentry: directory entry
+ * @mode: access mode
+ * @name: path name
+ * @context: resulting security context
+ *
+ * Use at most one security module to get the initial
+ * security context. Do not use the "display".
+ *
+ * Returns -EOPNOTSUPP if not supplied by any module or the module result.
+ */
 int security_dentry_init_security(struct dentry *dentry, int mode,
-					const struct qstr *name, void **ctx,
-					u32 *ctxlen)
+				  const struct qstr *name,
+				  struct lsmcontext *cp)
 {
-	return call_int_hook(dentry_init_security, -EOPNOTSUPP, dentry, mode,
-				name, ctx, ctxlen);
+	struct security_hook_list *hp;
+
+	hlist_for_each_entry(hp, &security_hook_heads.dentry_init_security,
+			     list) {
+		cp->slot = hp->lsmid->slot;
+		return hp->hook.dentry_init_security(dentry, mode, name,
+						     (void **)&cp->context,
+						     &cp->len);
+	}
+
+	return -EOPNOTSUPP;
 }
 EXPORT_SYMBOL(security_dentry_init_security);
 
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 17/28] LSM: Use lsmcontext in security_secid_to_secctx
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Replace the (secctx,seclen) pointer pair with a single
lsmcontext pointer to allow return of the LSM identifier
along with the context and context length. This allows
security_release_secctx() to know how to release the
context. Callers have been modified to use or save the
returned data from the new structure.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 drivers/android/binder.c                | 24 ++++++---------
 include/linux/security.h                |  4 +--
 include/net/scm.h                       | 10 ++-----
 kernel/audit.c                          | 29 +++++++-----------
 kernel/auditsc.c                        | 31 +++++++------------
 net/ipv4/ip_sockglue.c                  |  7 ++---
 net/netfilter/nf_conntrack_netlink.c    | 14 +++++----
 net/netfilter/nf_conntrack_standalone.c |  7 ++---
 net/netfilter/nfnetlink_queue.c         |  5 +++-
 net/netlabel/netlabel_unlabeled.c       | 40 ++++++++-----------------
 net/netlabel/netlabel_user.c            |  7 ++---
 security/security.c                     | 10 +++++--
 12 files changed, 73 insertions(+), 115 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 89e574be34cc..90bc4ce07cd2 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -2874,9 +2874,7 @@ static void binder_transaction(struct binder_proc *proc,
 	binder_size_t last_fixup_min_off = 0;
 	struct binder_context *context = proc->context;
 	int t_debug_id = atomic_inc_return(&binder_last_id);
-	char *secctx = NULL;
-	u32 secctx_sz = 0;
-	struct lsmcontext scaff; /* scaffolding */
+	struct lsmcontext lsmctx = { };
 
 	e = binder_transaction_log_add(&binder_transaction_log);
 	e->debug_id = t_debug_id;
@@ -3123,14 +3121,14 @@ static void binder_transaction(struct binder_proc *proc,
 		struct lsmblob blob;
 
 		security_task_getsecid(proc->tsk, &blob);
-		ret = security_secid_to_secctx(&blob, &secctx, &secctx_sz);
+		ret = security_secid_to_secctx(&blob, &lsmctx);
 		if (ret) {
 			return_error = BR_FAILED_REPLY;
 			return_error_param = ret;
 			return_error_line = __LINE__;
 			goto err_get_secctx_failed;
 		}
-		extra_buffers_size += ALIGN(secctx_sz, sizeof(u64));
+		extra_buffers_size += ALIGN(lsmctx.len, sizeof(u64));
 	}
 
 	trace_binder_transaction(reply, t, target_node);
@@ -3149,19 +3147,17 @@ static void binder_transaction(struct binder_proc *proc,
 		t->buffer = NULL;
 		goto err_binder_alloc_buf_failed;
 	}
-	if (secctx) {
+	if (lsmctx.context) {
 		size_t buf_offset = ALIGN(tr->data_size, sizeof(void *)) +
 				    ALIGN(tr->offsets_size, sizeof(void *)) +
 				    ALIGN(extra_buffers_size, sizeof(void *)) -
-				    ALIGN(secctx_sz, sizeof(u64));
+				    ALIGN(lsmctx.len, sizeof(u64));
 
 		t->security_ctx = (uintptr_t)t->buffer->user_data + buf_offset;
 		binder_alloc_copy_to_buffer(&target_proc->alloc,
 					    t->buffer, buf_offset,
-					    secctx, secctx_sz);
-		lsmcontext_init(&scaff, secctx, secctx_sz, 0);
-		security_release_secctx(&scaff);
-		secctx = NULL;
+					    lsmctx.context, lsmctx.len);
+		security_release_secctx(&lsmctx);
 	}
 	t->buffer->debug_id = t->debug_id;
 	t->buffer->transaction = t;
@@ -3481,10 +3477,8 @@ static void binder_transaction(struct binder_proc *proc,
 	t->buffer->transaction = NULL;
 	binder_alloc_free_buf(&target_proc->alloc, t->buffer);
 err_binder_alloc_buf_failed:
-	if (secctx) {
-		lsmcontext_init(&scaff, secctx, secctx_sz, 0);
-		security_release_secctx(&scaff);
-	}
+	if (lsmctx.context)
+		security_release_secctx(&lsmctx);
 err_get_secctx_failed:
 	kfree(tcomplete);
 	binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
diff --git a/include/linux/security.h b/include/linux/security.h
index 046012a7255f..7255825aa697 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -481,7 +481,7 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
 			 size_t size);
 int security_netlink_send(struct sock *sk, struct sk_buff *skb);
 int security_ismaclabel(const char *name);
-int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen);
+int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp);
 int security_secctx_to_secid(const char *secdata, u32 seclen,
 			     struct lsmblob *blob);
 void security_release_secctx(struct lsmcontext *cp);
@@ -1263,7 +1263,7 @@ static inline int security_ismaclabel(const char *name)
 }
 
 static inline int security_secid_to_secctx(struct lsmblob *blob,
-					   char **secdata, u32 *seclen)
+					   struct lsmcontext *cp)
 {
 	return -EOPNOTSUPP;
 }
diff --git a/include/net/scm.h b/include/net/scm.h
index 30ba801c91bd..4a6ad8caf423 100644
--- a/include/net/scm.h
+++ b/include/net/scm.h
@@ -93,18 +93,14 @@ static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
 static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
 {
 	struct lsmcontext context;
-	char *secdata;
-	u32 seclen;
 	int err;
 
 	if (test_bit(SOCK_PASSSEC, &sock->flags)) {
-		err = security_secid_to_secctx(&scm->lsmblob, &secdata,
-					       &seclen);
+		err = security_secid_to_secctx(&scm->lsmblob, &context);
 
 		if (!err) {
-			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
-			/*scaffolding*/
-			lsmcontext_init(&context, secdata, seclen, 0);
+			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY,
+				 context.len, context.context);
 			security_release_secctx(&context);
 		}
 	}
diff --git a/kernel/audit.c b/kernel/audit.c
index f844a2a642e6..e1dfd9c6df36 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1191,9 +1191,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	struct audit_buffer	*ab;
 	u16			msg_type = nlh->nlmsg_type;
 	struct audit_sig_info   *sig_data;
-	char			*ctx = NULL;
 	u32			len;
-	struct lsmcontext	scaff; /* scaffolding */
+	struct lsmcontext	context = { };
 
 	err = audit_netlink_ok(skb, msg_type);
 	if (err)
@@ -1431,25 +1430,22 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	case AUDIT_SIGNAL_INFO:
 		len = 0;
 		if (lsmblob_is_set(&audit_sig_lsm)) {
-			err = security_secid_to_secctx(&audit_sig_lsm, &ctx,
-						       &len);
+			err = security_secid_to_secctx(&audit_sig_lsm,
+						       &context);
 			if (err)
 				return err;
 		}
 		sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
 		if (!sig_data) {
-			if (lsmblob_is_set(&audit_sig_lsm)) {
-				lsmcontext_init(&scaff, ctx, len, 0);
-				security_release_secctx(&scaff);
-			}
+			if (lsmblob_is_set(&audit_sig_lsm))
+				security_release_secctx(&context);
 			return -ENOMEM;
 		}
 		sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
 		sig_data->pid = audit_sig_pid;
 		if (lsmblob_is_set(&audit_sig_lsm)) {
-			memcpy(sig_data->ctx, ctx, len);
-			lsmcontext_init(&scaff, ctx, len, 0);
-			security_release_secctx(&scaff);
+			memcpy(sig_data->ctx, context.context, context.len);
+			security_release_secctx(&context);
 		}
 		audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
 				 sig_data, sizeof(*sig_data) + len);
@@ -2074,26 +2070,23 @@ void audit_log_key(struct audit_buffer *ab, char *key)
 
 int audit_log_task_context(struct audit_buffer *ab)
 {
-	char *ctx = NULL;
-	unsigned len;
 	int error;
 	struct lsmblob blob;
-	struct lsmcontext scaff; /* scaffolding */
+	struct lsmcontext context;
 
 	security_task_getsecid(current, &blob);
 	if (!lsmblob_is_set(&blob))
 		return 0;
 
-	error = security_secid_to_secctx(&blob, &ctx, &len);
+	error = security_secid_to_secctx(&blob, &context);
 	if (error) {
 		if (error != -EINVAL)
 			goto error_path;
 		return 0;
 	}
 
-	audit_log_format(ab, " subj=%s", ctx);
-	lsmcontext_init(&scaff, ctx, len, 0);
-	security_release_secctx(&scaff);
+	audit_log_format(ab, " subj=%s", context.context);
+	security_release_secctx(&context);
 	return 0;
 
 error_path:
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 9fab0e7d90c3..0478680cd0a8 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -943,9 +943,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 				 struct lsmblob *blob, char *comm)
 {
 	struct audit_buffer *ab;
-	struct lsmcontext lsmcxt;
-	char *ctx = NULL;
-	u32 len;
+	struct lsmcontext lsmctx;
 	int rc = 0;
 
 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
@@ -956,13 +954,12 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 			 from_kuid(&init_user_ns, auid),
 			 from_kuid(&init_user_ns, uid), sessionid);
 	if (lsmblob_is_set(blob)) {
-		if (security_secid_to_secctx(blob, &ctx, &len)) {
+		if (security_secid_to_secctx(blob, &lsmctx)) {
 			audit_log_format(ab, " obj=(none)");
 			rc = 1;
 		} else {
-			audit_log_format(ab, " obj=%s", ctx);
-			lsmcontext_init(&lsmcxt, ctx, len, 0); /*scaffolding*/
-			security_release_secctx(&lsmcxt);
+			audit_log_format(ab, " obj=%s", lsmctx.context);
+			security_release_secctx(&lsmctx);
 		}
 	}
 	audit_log_format(ab, " ocomm=");
@@ -1174,7 +1171,6 @@ static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
 
 static void show_special(struct audit_context *context, int *call_panic)
 {
-	struct lsmcontext lsmcxt;
 	struct audit_buffer *ab;
 	int i;
 
@@ -1198,17 +1194,15 @@ static void show_special(struct audit_context *context, int *call_panic)
 				 from_kgid(&init_user_ns, context->ipc.gid),
 				 context->ipc.mode);
 		if (osid) {
-			char *ctx = NULL;
-			u32 len;
+			struct lsmcontext lsmcxt;
 			struct lsmblob blob;
 
 			lsmblob_init(&blob, osid);
-			if (security_secid_to_secctx(&blob, &ctx, &len)) {
+			if (security_secid_to_secctx(&blob, &lsmcxt)) {
 				audit_log_format(ab, " osid=%u", osid);
 				*call_panic = 1;
 			} else {
-				audit_log_format(ab, " obj=%s", ctx);
-				lsmcontext_init(&lsmcxt, ctx, len, 0);
+				audit_log_format(ab, " obj=%s", lsmcxt.context);
 				security_release_secctx(&lsmcxt);
 			}
 		}
@@ -1353,20 +1347,17 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
 				 MAJOR(n->rdev),
 				 MINOR(n->rdev));
 	if (n->osid != 0) {
-		char *ctx = NULL;
-		u32 len;
 		struct lsmblob blob;
-		struct lsmcontext lsmcxt;
+		struct lsmcontext lsmctx;
 
 		lsmblob_init(&blob, n->osid);
-		if (security_secid_to_secctx(&blob, &ctx, &len)) {
+		if (security_secid_to_secctx(&blob, &lsmctx)) {
 			audit_log_format(ab, " osid=%u", n->osid);
 			if (call_panic)
 				*call_panic = 2;
 		} else {
-			audit_log_format(ab, " obj=%s", ctx);
-			lsmcontext_init(&lsmcxt, ctx, len, 0); /* scaffolding */
-			security_release_secctx(&lsmcxt);
+			audit_log_format(ab, " obj=%s", lsmctx.context);
+			security_release_secctx(&lsmctx);
 		}
 	}
 
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 7834c357b60b..80ae0c5a1301 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -132,20 +132,17 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
 {
 	struct lsmcontext context;
 	struct lsmblob lb;
-	char *secdata;
-	u32 seclen;
 	int err;
 
 	err = security_socket_getpeersec_dgram(NULL, skb, &lb);
 	if (err)
 		return;
 
-	err = security_secid_to_secctx(&lb, &secdata, &seclen);
+	err = security_secid_to_secctx(&lb, &context);
 	if (err)
 		return;
 
-	put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
-	lsmcontext_init(&context, secdata, seclen, 0); /* scaffolding */
+	put_cmsg(msg, SOL_IP, SCM_SECURITY, context.len, context.context);
 	security_release_secctx(&context);
 }
 
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 6954e6600583..403307ff0fff 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -328,13 +328,12 @@ static int ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
 static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
 {
 	struct nlattr *nest_secctx;
-	int len, ret;
-	char *secctx;
+	int ret;
 	struct lsmblob blob;
 	struct lsmcontext context;
 
 	lsmblob_init(&blob, ct->secmark);
-	ret = security_secid_to_secctx(&blob, &secctx, &len);
+	ret = security_secid_to_secctx(&blob, &context);
 	if (ret)
 		return 0;
 
@@ -343,13 +342,12 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
 	if (!nest_secctx)
 		goto nla_put_failure;
 
-	if (nla_put_string(skb, CTA_SECCTX_NAME, secctx))
+	if (nla_put_string(skb, CTA_SECCTX_NAME, context.context))
 		goto nla_put_failure;
 	nla_nest_end(skb, nest_secctx);
 
 	ret = 0;
 nla_put_failure:
-	lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
 	security_release_secctx(&context);
 	return ret;
 }
@@ -620,12 +618,16 @@ static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
 #ifdef CONFIG_NF_CONNTRACK_SECMARK
 	int len, ret;
 	struct lsmblob blob;
+	struct lsmcontext context;
 
 	lsmblob_init(&blob, ct->secmark);
-	ret = security_secid_to_secctx(&blob, NULL, &len);
+	ret = security_secid_to_secctx(&blob, &context);
 	if (ret)
 		return 0;
 
+	len = context.len;
+	security_release_secctx(&context);
+
 	return nla_total_size(0) /* CTA_SECCTX */
 	       + nla_total_size(sizeof(char) * len); /* CTA_SECCTX_NAME */
 #else
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index 79158ad0486e..fcb51ab2bb8b 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -173,19 +173,16 @@ static void ct_seq_stop(struct seq_file *s, void *v)
 static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 {
 	int ret;
-	u32 len;
-	char *secctx;
 	struct lsmblob blob;
 	struct lsmcontext context;
 
 	lsmblob_init(&blob, ct->secmark);
-	ret = security_secid_to_secctx(&blob, &secctx, &len);
+	ret = security_secid_to_secctx(&blob, &context);
 	if (ret)
 		return;
 
-	seq_printf(s, "secctx=%s ", secctx);
+	seq_printf(s, "secctx=%s ", context.context);
 
-	lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
 	security_release_secctx(&context);
 }
 #else
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index fe8403ef4e89..5593ee05d106 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -310,6 +310,7 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
 	u32 seclen = 0;
 #if IS_ENABLED(CONFIG_NETWORK_SECMARK)
 	struct lsmblob blob;
+	struct lsmcontext context = { };
 
 	if (!skb || !sk_fullsock(skb->sk))
 		return 0;
@@ -318,10 +319,12 @@ static u32 nfqnl_get_sk_secctx(struct sk_buff *skb, char **secdata)
 
 	if (skb->secmark) {
 		lsmblob_init(&blob, skb->secmark);
-		security_secid_to_secctx(&blob, secdata, &seclen);
+		security_secid_to_secctx(&blob, &context);
+		*secdata = context.context;
 	}
 
 	read_unlock_bh(&skb->sk->sk_callback_lock);
+	seclen = context.len;
 #endif
 	return seclen;
 }
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 15b1945853be..4716e0011ba5 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -388,8 +388,6 @@ int netlbl_unlhsh_add(struct net *net,
 	struct netlbl_unlhsh_iface *iface;
 	struct audit_buffer *audit_buf = NULL;
 	struct lsmcontext context;
-	char *secctx = NULL;
-	u32 secctx_len;
 	struct lsmblob blob;
 
 	if (addr_len != sizeof(struct in_addr) &&
@@ -454,12 +452,9 @@ int netlbl_unlhsh_add(struct net *net,
 	rcu_read_unlock();
 	if (audit_buf != NULL) {
 		lsmblob_init(&blob, secid);
-		if (security_secid_to_secctx(&blob,
-					     &secctx,
-					     &secctx_len) == 0) {
-			audit_log_format(audit_buf, " sec_obj=%s", secctx);
-			/* scaffolding */
-			lsmcontext_init(&context, secctx, secctx_len, 0);
+		if (security_secid_to_secctx(&blob, &context) == 0) {
+			audit_log_format(audit_buf, " sec_obj=%s",
+					 context.context);
 			security_release_secctx(&context);
 		}
 		audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
@@ -492,8 +487,6 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
 	struct audit_buffer *audit_buf;
 	struct net_device *dev;
 	struct lsmcontext context;
-	char *secctx;
-	u32 secctx_len;
 	struct lsmblob blob;
 
 	spin_lock(&netlbl_unlhsh_lock);
@@ -517,11 +510,9 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
 		if (entry != NULL)
 			lsmblob_init(&blob, entry->secid);
 		if (entry != NULL &&
-		    security_secid_to_secctx(&blob,
-					     &secctx, &secctx_len) == 0) {
-			audit_log_format(audit_buf, " sec_obj=%s", secctx);
-			/* scaffolding */
-			lsmcontext_init(&context, secctx, secctx_len, 0);
+		    security_secid_to_secctx(&blob, &context) == 0) {
+			audit_log_format(audit_buf, " sec_obj=%s",
+					 context.context);
 			security_release_secctx(&context);
 		}
 		audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
@@ -560,8 +551,6 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
 	struct audit_buffer *audit_buf;
 	struct net_device *dev;
 	struct lsmcontext context;
-	char *secctx;
-	u32 secctx_len;
 	struct lsmblob blob;
 
 	spin_lock(&netlbl_unlhsh_lock);
@@ -584,10 +573,9 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
 		if (entry != NULL)
 			lsmblob_init(&blob, entry->secid);
 		if (entry != NULL &&
-		    security_secid_to_secctx(&blob,
-					     &secctx, &secctx_len) == 0) {
-			audit_log_format(audit_buf, " sec_obj=%s", secctx);
-			lsmcontext_init(&context, secctx, secctx_len, 0);
+		    security_secid_to_secctx(&blob, &context) == 0) {
+			audit_log_format(audit_buf, " sec_obj=%s",
+					 context.context);
 			security_release_secctx(&context);
 		}
 		audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
@@ -1105,8 +1093,6 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
 	struct lsmcontext context;
 	void *data;
 	u32 secid;
-	char *secctx;
-	u32 secctx_len;
 	struct lsmblob blob;
 
 	data = genlmsg_put(cb_arg->skb, NETLINK_CB(cb_arg->nl_cb->skb).portid,
@@ -1163,15 +1149,13 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
 	}
 
 	lsmblob_init(&blob, secid);
-	ret_val = security_secid_to_secctx(&blob, &secctx, &secctx_len);
+	ret_val = security_secid_to_secctx(&blob, &context);
 	if (ret_val != 0)
 		goto list_cb_failure;
 	ret_val = nla_put(cb_arg->skb,
 			  NLBL_UNLABEL_A_SECCTX,
-			  secctx_len,
-			  secctx);
-	/* scaffolding */
-	lsmcontext_init(&context, secctx, secctx_len, 0);
+			  context.len,
+			  context.context);
 	security_release_secctx(&context);
 	if (ret_val != 0)
 		goto list_cb_failure;
diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
index 94aea4985b74..2d1307f65250 100644
--- a/net/netlabel/netlabel_user.c
+++ b/net/netlabel/netlabel_user.c
@@ -99,8 +99,6 @@ struct audit_buffer *netlbl_audit_start_common(int type,
 {
 	struct audit_buffer *audit_buf;
 	struct lsmcontext context;
-	char *secctx;
-	u32 secctx_len;
 	struct lsmblob blob;
 
 	if (audit_enabled == AUDIT_OFF)
@@ -116,9 +114,8 @@ struct audit_buffer *netlbl_audit_start_common(int type,
 
 	lsmblob_init(&blob, audit_info->secid);
 	if (audit_info->secid != 0 &&
-	    security_secid_to_secctx(&blob, &secctx, &secctx_len) == 0) {
-		audit_log_format(audit_buf, " subj=%s", secctx);
-		lsmcontext_init(&context, secctx, secctx_len, 0);/*scaffolding*/
+	    security_secid_to_secctx(&blob, &context) == 0) {
+		audit_log_format(audit_buf, " subj=%s", context.context);
 		security_release_secctx(&context);
 	}
 
diff --git a/security/security.c b/security/security.c
index 2b355c2a53f3..38e10f92dae3 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2100,18 +2100,22 @@ int security_ismaclabel(const char *name)
 }
 EXPORT_SYMBOL(security_ismaclabel);
 
-int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen)
+int security_secid_to_secctx(struct lsmblob *blob, struct lsmcontext *cp)
 {
 	struct security_hook_list *hp;
 	int display = lsm_task_display(current);
 
+	memset(cp, 0, sizeof(*cp));
+
 	hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
 		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
 			continue;
-		if (display == LSMBLOB_INVALID || display == hp->lsmid->slot)
+		if (display == LSMBLOB_INVALID || display == hp->lsmid->slot) {
+			cp->slot = hp->lsmid->slot;
 			return hp->hook.secid_to_secctx(
 					blob->secid[hp->lsmid->slot],
-					secdata, seclen);
+					&cp->context, &cp->len);
+		}
 	}
 	return 0;
 }
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 16/28] LSM: Ensure the correct LSM context releaser
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Add a new lsmcontext data structure to hold all the information
about a "security context", including the string, its size and
which LSM allocated the string. The allocation information is
necessary because LSMs have different policies regarding the
lifecycle of these strings. SELinux allocates and destroys
them on each use, whereas Smack provides a pointer to an entry
in a list that never goes away.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 drivers/android/binder.c                | 10 +++++--
 fs/kernfs/dir.c                         | 10 +++++--
 fs/kernfs/inode.c                       |  7 +++--
 fs/nfs/nfs4proc.c                       |  8 +++--
 fs/nfsd/nfs4xdr.c                       |  7 +++--
 include/linux/security.h                | 39 +++++++++++++++++++++++--
 include/net/scm.h                       |  5 +++-
 kernel/audit.c                          | 14 ++++++---
 kernel/auditsc.c                        | 12 ++++++--
 net/ipv4/ip_sockglue.c                  |  4 ++-
 net/netfilter/nf_conntrack_netlink.c    |  4 ++-
 net/netfilter/nf_conntrack_standalone.c |  4 ++-
 net/netfilter/nfnetlink_queue.c         | 13 ++++++---
 net/netlabel/netlabel_unlabeled.c       | 19 +++++++++---
 net/netlabel/netlabel_user.c            |  4 ++-
 security/security.c                     | 18 ++++++++----
 security/smack/smack_lsm.c              | 14 ++++++---
 17 files changed, 148 insertions(+), 44 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c
index 144ac4f1c24f..89e574be34cc 100644
--- a/drivers/android/binder.c
+++ b/drivers/android/binder.c
@@ -2876,6 +2876,7 @@ static void binder_transaction(struct binder_proc *proc,
 	int t_debug_id = atomic_inc_return(&binder_last_id);
 	char *secctx = NULL;
 	u32 secctx_sz = 0;
+	struct lsmcontext scaff; /* scaffolding */
 
 	e = binder_transaction_log_add(&binder_transaction_log);
 	e->debug_id = t_debug_id;
@@ -3158,7 +3159,8 @@ static void binder_transaction(struct binder_proc *proc,
 		binder_alloc_copy_to_buffer(&target_proc->alloc,
 					    t->buffer, buf_offset,
 					    secctx, secctx_sz);
-		security_release_secctx(secctx, secctx_sz);
+		lsmcontext_init(&scaff, secctx, secctx_sz, 0);
+		security_release_secctx(&scaff);
 		secctx = NULL;
 	}
 	t->buffer->debug_id = t->debug_id;
@@ -3479,8 +3481,10 @@ static void binder_transaction(struct binder_proc *proc,
 	t->buffer->transaction = NULL;
 	binder_alloc_free_buf(&target_proc->alloc, t->buffer);
 err_binder_alloc_buf_failed:
-	if (secctx)
-		security_release_secctx(secctx, secctx_sz);
+	if (secctx) {
+		lsmcontext_init(&scaff, secctx, secctx_sz, 0);
+		security_release_secctx(&scaff);
+	}
 err_get_secctx_failed:
 	kfree(tcomplete);
 	binder_stats_deleted(BINDER_STAT_TRANSACTION_COMPLETE);
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index b84d635567d3..c8362b6d556e 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -532,9 +532,13 @@ void kernfs_put(struct kernfs_node *kn)
 	kfree_const(kn->name);
 
 	if (kn->iattr) {
-		if (kn->iattr->ia_secdata)
-			security_release_secctx(kn->iattr->ia_secdata,
-						kn->iattr->ia_secdata_len);
+		struct lsmcontext scaff; /* scaffolding */
+
+		if (kn->iattr->ia_secdata) {
+			lsmcontext_init(&scaff, kn->iattr->ia_secdata,
+					kn->iattr->ia_secdata_len, 0);
+			security_release_secctx(&scaff);
+		}
 		simple_xattrs_free(&kn->iattr->xattrs);
 		kmem_cache_free(kernfs_iattrs_cache, kn->iattr);
 	}
diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c
index 0c1fd945ce42..02cde9dac5ee 100644
--- a/fs/kernfs/inode.c
+++ b/fs/kernfs/inode.c
@@ -349,6 +349,7 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler,
 {
 	struct kernfs_node *kn = inode->i_private;
 	struct kernfs_iattrs *attrs;
+	struct lsmcontext context;
 	void *secdata;
 	u32 secdata_len = 0;
 	int error;
@@ -368,8 +369,10 @@ static int kernfs_security_xattr_set(const struct xattr_handler *handler,
 	error = kernfs_node_setsecdata(attrs, &secdata, &secdata_len);
 	mutex_unlock(&kernfs_mutex);
 
-	if (secdata)
-		security_release_secctx(secdata, secdata_len);
+	if (secdata) {
+		lsmcontext_init(&context, secdata, secdata_len, 0);
+		security_release_secctx(&context);
+	}
 	return error;
 }
 
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 4dbb0ee23432..af1c0db29c39 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -131,8 +131,12 @@ nfs4_label_init_security(struct inode *dir, struct dentry *dentry,
 static inline void
 nfs4_label_release_security(struct nfs4_label *label)
 {
-	if (label)
-		security_release_secctx(label->label, label->len);
+	struct lsmcontext scaff; /* scaffolding */
+
+	if (label) {
+		lsmcontext_init(&scaff, label->label, label->len, 0);
+		security_release_secctx(&scaff);
+	}
 }
 static inline u32 *nfs4_bitmask(struct nfs_server *server, struct nfs4_label *label)
 {
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 3de42a729093..bb3db033e144 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -2420,6 +2420,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
 	__be32 status;
 	int err;
 	struct nfs4_acl *acl = NULL;
+	struct lsmcontext scaff; /* scaffolding */
 	void *context = NULL;
 	int contextlen;
 	bool contextsupport = false;
@@ -2919,8 +2920,10 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
 
 out:
 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
-	if (context)
-		security_release_secctx(context, contextlen);
+	if (context) {
+		lsmcontext_init(&scaff, context, contextlen, 0); /*scaffolding*/
+		security_release_secctx(&scaff);
+	}
 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
 	kfree(acl);
 	if (tempfh) {
diff --git a/include/linux/security.h b/include/linux/security.h
index d310fa3942ce..046012a7255f 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -76,6 +76,41 @@ enum lsm_event {
 	LSM_POLICY_CHANGE,
 };
 
+/*
+ * A "security context" is the text representation of
+ * the information used by LSMs.
+ * This structure contains the string, its length, and which LSM
+ * it is useful for.
+ */
+struct lsmcontext {
+	char	*context;	/* Provided by the module */
+	u32	len;
+	int	slot;		/* Identifies the module */
+};
+
+/**
+ * lsmcontext_init - initialize an lsmcontext structure.
+ * @cp: Pointer to the context to initialize
+ * @context: Initial context, or NULL
+ * @size: Size of context, or 0
+ * @slot: Which LSM provided the context
+ *
+ * Fill in the lsmcontext from the provided information.
+ * This is a scaffolding function that will be removed when
+ * lsmcontext integration is complete.
+ */
+static inline void lsmcontext_init(struct lsmcontext *cp, char *context,
+				   u32 size, int slot)
+{
+	cp->slot = slot;
+	cp->context = context;
+
+	if (context == NULL || size == 0)
+		cp->len = 0;
+	else
+		cp->len = strlen(context);
+}
+
 /*
  * Data exported by the security modules
  *
@@ -449,7 +484,7 @@ int security_ismaclabel(const char *name);
 int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen);
 int security_secctx_to_secid(const char *secdata, u32 seclen,
 			     struct lsmblob *blob);
-void security_release_secctx(char *secdata, u32 seclen);
+void security_release_secctx(struct lsmcontext *cp);
 
 void security_inode_invalidate_secctx(struct inode *inode);
 int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen);
@@ -1240,7 +1275,7 @@ static inline int security_secctx_to_secid(const char *secdata,
 	return -EOPNOTSUPP;
 }
 
-static inline void security_release_secctx(char *secdata, u32 seclen)
+static inline void security_release_secctx(struct lsmcontext *cp)
 {
 }
 
diff --git a/include/net/scm.h b/include/net/scm.h
index 31ae605fcc0a..30ba801c91bd 100644
--- a/include/net/scm.h
+++ b/include/net/scm.h
@@ -92,6 +92,7 @@ static __inline__ int scm_send(struct socket *sock, struct msghdr *msg,
 #ifdef CONFIG_SECURITY_NETWORK
 static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct scm_cookie *scm)
 {
+	struct lsmcontext context;
 	char *secdata;
 	u32 seclen;
 	int err;
@@ -102,7 +103,9 @@ static inline void scm_passec(struct socket *sock, struct msghdr *msg, struct sc
 
 		if (!err) {
 			put_cmsg(msg, SOL_SOCKET, SCM_SECURITY, seclen, secdata);
-			security_release_secctx(secdata, seclen);
+			/*scaffolding*/
+			lsmcontext_init(&context, secdata, seclen, 0);
+			security_release_secctx(&context);
 		}
 	}
 }
diff --git a/kernel/audit.c b/kernel/audit.c
index 1b51e907f131..f844a2a642e6 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -1193,6 +1193,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	struct audit_sig_info   *sig_data;
 	char			*ctx = NULL;
 	u32			len;
+	struct lsmcontext	scaff; /* scaffolding */
 
 	err = audit_netlink_ok(skb, msg_type);
 	if (err)
@@ -1437,15 +1438,18 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 		}
 		sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
 		if (!sig_data) {
-			if (lsmblob_is_set(&audit_sig_lsm))
-				security_release_secctx(ctx, len);
+			if (lsmblob_is_set(&audit_sig_lsm)) {
+				lsmcontext_init(&scaff, ctx, len, 0);
+				security_release_secctx(&scaff);
+			}
 			return -ENOMEM;
 		}
 		sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
 		sig_data->pid = audit_sig_pid;
 		if (lsmblob_is_set(&audit_sig_lsm)) {
 			memcpy(sig_data->ctx, ctx, len);
-			security_release_secctx(ctx, len);
+			lsmcontext_init(&scaff, ctx, len, 0);
+			security_release_secctx(&scaff);
 		}
 		audit_send_reply(skb, seq, AUDIT_SIGNAL_INFO, 0, 0,
 				 sig_data, sizeof(*sig_data) + len);
@@ -2074,6 +2078,7 @@ int audit_log_task_context(struct audit_buffer *ab)
 	unsigned len;
 	int error;
 	struct lsmblob blob;
+	struct lsmcontext scaff; /* scaffolding */
 
 	security_task_getsecid(current, &blob);
 	if (!lsmblob_is_set(&blob))
@@ -2087,7 +2092,8 @@ int audit_log_task_context(struct audit_buffer *ab)
 	}
 
 	audit_log_format(ab, " subj=%s", ctx);
-	security_release_secctx(ctx, len);
+	lsmcontext_init(&scaff, ctx, len, 0);
+	security_release_secctx(&scaff);
 	return 0;
 
 error_path:
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index c7aa39bda5cc..9fab0e7d90c3 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -943,6 +943,7 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 				 struct lsmblob *blob, char *comm)
 {
 	struct audit_buffer *ab;
+	struct lsmcontext lsmcxt;
 	char *ctx = NULL;
 	u32 len;
 	int rc = 0;
@@ -960,7 +961,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 			rc = 1;
 		} else {
 			audit_log_format(ab, " obj=%s", ctx);
-			security_release_secctx(ctx, len);
+			lsmcontext_init(&lsmcxt, ctx, len, 0); /*scaffolding*/
+			security_release_secctx(&lsmcxt);
 		}
 	}
 	audit_log_format(ab, " ocomm=");
@@ -1172,6 +1174,7 @@ static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
 
 static void show_special(struct audit_context *context, int *call_panic)
 {
+	struct lsmcontext lsmcxt;
 	struct audit_buffer *ab;
 	int i;
 
@@ -1205,7 +1208,8 @@ static void show_special(struct audit_context *context, int *call_panic)
 				*call_panic = 1;
 			} else {
 				audit_log_format(ab, " obj=%s", ctx);
-				security_release_secctx(ctx, len);
+				lsmcontext_init(&lsmcxt, ctx, len, 0);
+				security_release_secctx(&lsmcxt);
 			}
 		}
 		if (context->ipc.has_perm) {
@@ -1352,6 +1356,7 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
 		char *ctx = NULL;
 		u32 len;
 		struct lsmblob blob;
+		struct lsmcontext lsmcxt;
 
 		lsmblob_init(&blob, n->osid);
 		if (security_secid_to_secctx(&blob, &ctx, &len)) {
@@ -1360,7 +1365,8 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
 				*call_panic = 2;
 		} else {
 			audit_log_format(ab, " obj=%s", ctx);
-			security_release_secctx(ctx, len);
+			lsmcontext_init(&lsmcxt, ctx, len, 0); /* scaffolding */
+			security_release_secctx(&lsmcxt);
 		}
 	}
 
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index e05f4ef68bd8..7834c357b60b 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -130,6 +130,7 @@ static void ip_cmsg_recv_checksum(struct msghdr *msg, struct sk_buff *skb,
 
 static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
 {
+	struct lsmcontext context;
 	struct lsmblob lb;
 	char *secdata;
 	u32 seclen;
@@ -144,7 +145,8 @@ static void ip_cmsg_recv_security(struct msghdr *msg, struct sk_buff *skb)
 		return;
 
 	put_cmsg(msg, SOL_IP, SCM_SECURITY, seclen, secdata);
-	security_release_secctx(secdata, seclen);
+	lsmcontext_init(&context, secdata, seclen, 0); /* scaffolding */
+	security_release_secctx(&context);
 }
 
 static void ip_cmsg_recv_dstaddr(struct msghdr *msg, struct sk_buff *skb)
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index ca0968f13240..6954e6600583 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -331,6 +331,7 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
 	int len, ret;
 	char *secctx;
 	struct lsmblob blob;
+	struct lsmcontext context;
 
 	lsmblob_init(&blob, ct->secmark);
 	ret = security_secid_to_secctx(&blob, &secctx, &len);
@@ -348,7 +349,8 @@ static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
 
 	ret = 0;
 nla_put_failure:
-	security_release_secctx(secctx, len);
+	lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
+	security_release_secctx(&context);
 	return ret;
 }
 #else
diff --git a/net/netfilter/nf_conntrack_standalone.c b/net/netfilter/nf_conntrack_standalone.c
index c793103f3cd7..79158ad0486e 100644
--- a/net/netfilter/nf_conntrack_standalone.c
+++ b/net/netfilter/nf_conntrack_standalone.c
@@ -176,6 +176,7 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 	u32 len;
 	char *secctx;
 	struct lsmblob blob;
+	struct lsmcontext context;
 
 	lsmblob_init(&blob, ct->secmark);
 	ret = security_secid_to_secctx(&blob, &secctx, &len);
@@ -184,7 +185,8 @@ static void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
 
 	seq_printf(s, "secctx=%s ", secctx);
 
-	security_release_secctx(secctx, len);
+	lsmcontext_init(&context, secctx, len, 0); /* scaffolding */
+	security_release_secctx(&context);
 }
 #else
 static inline void ct_show_secctx(struct seq_file *s, const struct nf_conn *ct)
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 59211bff90ab..fe8403ef4e89 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -399,6 +399,7 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	enum ip_conntrack_info uninitialized_var(ctinfo);
 	struct nfnl_ct_hook *nfnl_ct;
 	bool csum_verify;
+	struct lsmcontext scaff; /* scaffolding */
 	char *secdata = NULL;
 	u32 seclen = 0;
 
@@ -629,8 +630,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	}
 
 	nlh->nlmsg_len = skb->len;
-	if (seclen)
-		security_release_secctx(secdata, seclen);
+	if (seclen) {
+		lsmcontext_init(&scaff, secdata, seclen, 0);
+		security_release_secctx(&scaff);
+	}
 	return skb;
 
 nla_put_failure:
@@ -638,8 +641,10 @@ nfqnl_build_packet_message(struct net *net, struct nfqnl_instance *queue,
 	kfree_skb(skb);
 	net_err_ratelimited("nf_queue: error creating packet message\n");
 nlmsg_failure:
-	if (seclen)
-		security_release_secctx(secdata, seclen);
+	if (seclen) {
+		lsmcontext_init(&scaff, secdata, seclen, 0);
+		security_release_secctx(&scaff);
+	}
 	return NULL;
 }
 
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index 2294aa9471e6..15b1945853be 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c
@@ -387,6 +387,7 @@ int netlbl_unlhsh_add(struct net *net,
 	struct net_device *dev;
 	struct netlbl_unlhsh_iface *iface;
 	struct audit_buffer *audit_buf = NULL;
+	struct lsmcontext context;
 	char *secctx = NULL;
 	u32 secctx_len;
 	struct lsmblob blob;
@@ -457,7 +458,9 @@ int netlbl_unlhsh_add(struct net *net,
 					     &secctx,
 					     &secctx_len) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s", secctx);
-			security_release_secctx(secctx, secctx_len);
+			/* scaffolding */
+			lsmcontext_init(&context, secctx, secctx_len, 0);
+			security_release_secctx(&context);
 		}
 		audit_log_format(audit_buf, " res=%u", ret_val == 0 ? 1 : 0);
 		audit_log_end(audit_buf);
@@ -488,6 +491,7 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
 	struct netlbl_unlhsh_addr4 *entry;
 	struct audit_buffer *audit_buf;
 	struct net_device *dev;
+	struct lsmcontext context;
 	char *secctx;
 	u32 secctx_len;
 	struct lsmblob blob;
@@ -516,7 +520,9 @@ static int netlbl_unlhsh_remove_addr4(struct net *net,
 		    security_secid_to_secctx(&blob,
 					     &secctx, &secctx_len) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s", secctx);
-			security_release_secctx(secctx, secctx_len);
+			/* scaffolding */
+			lsmcontext_init(&context, secctx, secctx_len, 0);
+			security_release_secctx(&context);
 		}
 		audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
 		audit_log_end(audit_buf);
@@ -553,6 +559,7 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
 	struct netlbl_unlhsh_addr6 *entry;
 	struct audit_buffer *audit_buf;
 	struct net_device *dev;
+	struct lsmcontext context;
 	char *secctx;
 	u32 secctx_len;
 	struct lsmblob blob;
@@ -580,7 +587,8 @@ static int netlbl_unlhsh_remove_addr6(struct net *net,
 		    security_secid_to_secctx(&blob,
 					     &secctx, &secctx_len) == 0) {
 			audit_log_format(audit_buf, " sec_obj=%s", secctx);
-			security_release_secctx(secctx, secctx_len);
+			lsmcontext_init(&context, secctx, secctx_len, 0);
+			security_release_secctx(&context);
 		}
 		audit_log_format(audit_buf, " res=%u", entry != NULL ? 1 : 0);
 		audit_log_end(audit_buf);
@@ -1094,6 +1102,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
 	int ret_val = -ENOMEM;
 	struct netlbl_unlhsh_walk_arg *cb_arg = arg;
 	struct net_device *dev;
+	struct lsmcontext context;
 	void *data;
 	u32 secid;
 	char *secctx;
@@ -1161,7 +1170,9 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd,
 			  NLBL_UNLABEL_A_SECCTX,
 			  secctx_len,
 			  secctx);
-	security_release_secctx(secctx, secctx_len);
+	/* scaffolding */
+	lsmcontext_init(&context, secctx, secctx_len, 0);
+	security_release_secctx(&context);
 	if (ret_val != 0)
 		goto list_cb_failure;
 
diff --git a/net/netlabel/netlabel_user.c b/net/netlabel/netlabel_user.c
index 2ccc6567e2a2..94aea4985b74 100644
--- a/net/netlabel/netlabel_user.c
+++ b/net/netlabel/netlabel_user.c
@@ -98,6 +98,7 @@ struct audit_buffer *netlbl_audit_start_common(int type,
 					       struct netlbl_audit *audit_info)
 {
 	struct audit_buffer *audit_buf;
+	struct lsmcontext context;
 	char *secctx;
 	u32 secctx_len;
 	struct lsmblob blob;
@@ -117,7 +118,8 @@ struct audit_buffer *netlbl_audit_start_common(int type,
 	if (audit_info->secid != 0 &&
 	    security_secid_to_secctx(&blob, &secctx, &secctx_len) == 0) {
 		audit_log_format(audit_buf, " subj=%s", secctx);
-		security_release_secctx(secctx, secctx_len);
+		lsmcontext_init(&context, secctx, secctx_len, 0);/*scaffolding*/
+		security_release_secctx(&context);
 	}
 
 	return audit_buf;
diff --git a/security/security.c b/security/security.c
index c3c9bd88b7af..2b355c2a53f3 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2135,17 +2135,23 @@ int security_secctx_to_secid(const char *secdata, u32 seclen,
 }
 EXPORT_SYMBOL(security_secctx_to_secid);
 
-void security_release_secctx(char *secdata, u32 seclen)
+void security_release_secctx(struct lsmcontext *cp)
 {
 	struct security_hook_list *hp;
-	int *display = current->security;
+	bool found = false;
 
 	hlist_for_each_entry(hp, &security_hook_heads.release_secctx, list)
-		if (display == NULL || *display == LSMBLOB_INVALID ||
-		    *display == hp->lsmid->slot) {
-			hp->hook.release_secctx(secdata, seclen);
-			return;
+		if (cp->slot == hp->lsmid->slot) {
+			hp->hook.release_secctx(cp->context, cp->len);
+			found = true;
+			break;
 		}
+
+	memset(cp, 0, sizeof(*cp));
+
+	if (!found)
+		pr_warn("%s context \"%s\" from slot %d not released\n",
+			__func__, cp->context, cp->slot);
 }
 EXPORT_SYMBOL(security_release_secctx);
 
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 7a0ead4da479..472cb2097d36 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -4439,11 +4439,16 @@ static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
 	return 0;
 }
 
-/*
- * There used to be a smack_release_secctx hook
- * that did nothing back when hooks were in a vector.
- * Now that there's a list such a hook adds cost.
+/**
+ * smack_release_secctx - do everything necessary to free a context
+ * @secdata: Unused
+ * @seclen: Unused
+ *
+ * Do nothing but hold a slot in the hooks list.
  */
+static void smack_release_secctx(char *secdata, u32 seclen)
+{
+}
 
 static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
 {
@@ -4688,6 +4693,7 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
 	LSM_HOOK_INIT(ismaclabel, smack_ismaclabel),
 	LSM_HOOK_INIT(secid_to_secctx, smack_secid_to_secctx),
 	LSM_HOOK_INIT(secctx_to_secid, smack_secctx_to_secid),
+	LSM_HOOK_INIT(release_secctx, smack_release_secctx),
 	LSM_HOOK_INIT(inode_notifysecctx, smack_inode_notifysecctx),
 	LSM_HOOK_INIT(inode_setsecctx, smack_inode_setsecctx),
 	LSM_HOOK_INIT(inode_getsecctx, smack_inode_getsecctx),
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 15/28] LSM: Specify which LSM to display
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Create a new entry "display" in /proc/.../attr for controlling
which LSM security information is displayed for a process.
The name of an active LSM that supplies hooks for human readable
data may be written to "display" to set the value. This requires
CAP_MAC_ADMIN privilege. The name of the LSM currently in use can
be read from "display". At this point there can only be one LSM
capable of display active. A helper function lsm_task_display()
is provided to get the display slot for a task_struct.

Note that procfs restricts writes in the attr directory to 'self'.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 fs/proc/base.c            |   1 +
 include/linux/lsm_hooks.h |  15 ++++
 security/security.c       | 148 +++++++++++++++++++++++++++++++++-----
 3 files changed, 147 insertions(+), 17 deletions(-)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index ddef482f1334..7bf70e041315 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2618,6 +2618,7 @@ static const struct pid_entry attr_dir_stuff[] = {
 	ATTR(NULL, "fscreate",		0666),
 	ATTR(NULL, "keycreate",		0666),
 	ATTR(NULL, "sockcreate",	0666),
+	ATTR(NULL, "display",		0666),
 #ifdef CONFIG_SECURITY_SMACK
 	DIR("smack",			0555,
 	    proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops),
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index fe1fb7a69ee5..33e5ab4af9f8 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -2134,4 +2134,19 @@ static inline void security_delete_hooks(struct security_hook_list *hooks,
 
 extern int lsm_inode_alloc(struct inode *inode);
 
+/**
+ * lsm_task_display - the "display LSM for this task
+ * @task: The task to report on
+ *
+ * Returns the task's display LSM slot.
+ */
+static inline int lsm_task_display(struct task_struct *task)
+{
+	int *display = task->security;
+
+	if (display)
+		return *display;
+	return LSMBLOB_INVALID;
+}
+
 #endif /* ! __LINUX_LSM_HOOKS_H */
diff --git a/security/security.c b/security/security.c
index 8927508b2142..c3c9bd88b7af 100644
--- a/security/security.c
+++ b/security/security.c
@@ -31,6 +31,7 @@
 #include <linux/backing-dev.h>
 #include <linux/string.h>
 #include <linux/msg.h>
+#include <linux/binfmts.h>
 #include <net/flow.h>
 #include <net/sock.h>
 
@@ -46,7 +47,14 @@ static struct kmem_cache *lsm_file_cache;
 static struct kmem_cache *lsm_inode_cache;
 
 char *lsm_names;
-static struct lsm_blob_sizes blob_sizes __lsm_ro_after_init;
+
+/*
+ * The task blob includes the "display" slot used for
+ * chosing which module presents contexts.
+ */
+static struct lsm_blob_sizes blob_sizes __lsm_ro_after_init = {
+	.lbs_task = sizeof(int),
+};
 
 /* Boot-time LSM user choice */
 static __initdata const char *chosen_lsm_order;
@@ -423,8 +431,10 @@ static int lsm_append(const char *new, char **result)
 
 /*
  * Current index to use while initializing the lsmblob secid list.
+ * Pointers to the LSM id structures for local use.
  */
 static int lsm_slot __lsm_ro_after_init;
+static struct lsm_id *lsm_slotlist[LSMBLOB_ENTRIES];
 
 /**
  * security_add_hooks - Add a modules hooks to the hook lists.
@@ -444,6 +454,7 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count,
 	if (lsmid->slot == LSMBLOB_NEEDED) {
 		if (lsm_slot >= LSMBLOB_ENTRIES)
 			panic("%s Too many LSMs registered.\n", __func__);
+		lsm_slotlist[lsm_slot] = lsmid;
 		lsmid->slot = lsm_slot++;
 		init_debug("%s assigned lsmblob slot %d\n", lsmid->lsm,
 			   lsmid->slot);
@@ -564,6 +575,8 @@ int lsm_inode_alloc(struct inode *inode)
  */
 static int lsm_task_alloc(struct task_struct *task)
 {
+	int *display;
+
 	if (blob_sizes.lbs_task == 0) {
 		task->security = NULL;
 		return 0;
@@ -572,6 +585,15 @@ static int lsm_task_alloc(struct task_struct *task)
 	task->security = kzalloc(blob_sizes.lbs_task, GFP_KERNEL);
 	if (task->security == NULL)
 		return -ENOMEM;
+
+	/*
+	 * The start of the task blob contains the "display" LSM slot number.
+	 * Start with it set to the invalid slot number, indicating that the
+	 * default first registered LSM be displayed.
+	 */
+	display = task->security;
+	*display = LSMBLOB_INVALID;
+
 	return 0;
 }
 
@@ -1563,14 +1585,26 @@ int security_file_open(struct file *file)
 
 int security_task_alloc(struct task_struct *task, unsigned long clone_flags)
 {
+	int *odisplay = current->security;
+	int *ndisplay;
 	int rc = lsm_task_alloc(task);
 
-	if (rc)
+	if (unlikely(rc))
 		return rc;
+
 	rc = call_int_hook(task_alloc, 0, task, clone_flags);
-	if (unlikely(rc))
+	if (unlikely(rc)) {
 		security_task_free(task);
-	return rc;
+		return rc;
+	}
+
+	if (odisplay) {
+		ndisplay = task->security;
+		if (ndisplay)
+			*ndisplay = *odisplay;
+	}
+
+	return 0;
 }
 
 void security_task_free(struct task_struct *task)
@@ -1967,23 +2001,89 @@ int security_getprocattr(struct task_struct *p, const char *lsm, char *name,
 				char **value)
 {
 	struct security_hook_list *hp;
+	int display = lsm_task_display(current);
+	int slot = 0;
+
+	if (!strcmp(name, "display")) {
+		/*
+		 * lsm_slot will be 0 if there are no displaying modules.
+		 */
+		if (lsm_slot == 0)
+			return -EINVAL;
+		if (display != LSMBLOB_INVALID)
+			slot = display;
+		*value = kstrdup(lsm_slotlist[slot]->lsm, GFP_KERNEL);
+		if (*value)
+			return strlen(*value);
+		return -ENOMEM;
+	}
 
 	hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
 		if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
 			continue;
+		if (lsm == NULL && display != LSMBLOB_INVALID &&
+		    display != hp->lsmid->slot)
+			continue;
 		return hp->hook.getprocattr(p, name, value);
 	}
 	return -EINVAL;
 }
 
+/**
+ * security_setprocattr - Set process attributes via /proc
+ * @lsm: name of module involved, or NULL
+ * @name: name of the attribute
+ * @value: value to set the attribute to
+ * @size: size of the value
+ *
+ * Set the process attribute for the specified security module
+ * to the specified value. Note that this can only be used to set
+ * the process attributes for the current, or "self" process.
+ * The /proc code has already done this check.
+ *
+ * Returns 0 on success, an appropriate code otherwise.
+ */
 int security_setprocattr(const char *lsm, const char *name, void *value,
 			 size_t size)
 {
 	struct security_hook_list *hp;
+	char *term;
+	char *cp;
+	int *display = current->security;
+	int rc = -EINVAL;
+	int slot = 0;
+
+	if (!strcmp(name, "display")) {
+		if (!capable(CAP_MAC_ADMIN))
+			return -EPERM;
+		/*
+		 * lsm_slot will be 0 if there are no displaying modules.
+		 */
+		if (lsm_slot == 0 || size == 0)
+			return -EINVAL;
+		term = kmemdup_nul(value, size, GFP_KERNEL);
+		if (term == NULL)
+			return -ENOMEM;
+
+		cp = strsep(&term, " \n");
+
+		for (slot = 0; slot < lsm_slot; slot++)
+			if (!strcmp(cp, lsm_slotlist[slot]->lsm)) {
+				*display = lsm_slotlist[slot]->slot;
+				rc = size;
+				break;
+			}
+
+		kfree(cp);
+		return rc;
+	}
 
 	hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
 		if (lsm != NULL && strcmp(lsm, hp->lsmid->lsm))
 			continue;
+		if (lsm == NULL && *display != LSMBLOB_INVALID &&
+		    *display != hp->lsmid->slot)
+			continue;
 		return hp->hook.setprocattr(name, value, size);
 	}
 	return -EINVAL;
@@ -2003,15 +2103,15 @@ EXPORT_SYMBOL(security_ismaclabel);
 int security_secid_to_secctx(struct lsmblob *blob, char **secdata, u32 *seclen)
 {
 	struct security_hook_list *hp;
-	int rc;
+	int display = lsm_task_display(current);
 
 	hlist_for_each_entry(hp, &security_hook_heads.secid_to_secctx, list) {
 		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
 			continue;
-		rc = hp->hook.secid_to_secctx(blob->secid[hp->lsmid->slot],
-					      secdata, seclen);
-		if (rc != 0)
-			return rc;
+		if (display == LSMBLOB_INVALID || display == hp->lsmid->slot)
+			return hp->hook.secid_to_secctx(
+					blob->secid[hp->lsmid->slot],
+					secdata, seclen);
 	}
 	return 0;
 }
@@ -2021,16 +2121,15 @@ int security_secctx_to_secid(const char *secdata, u32 seclen,
 			     struct lsmblob *blob)
 {
 	struct security_hook_list *hp;
-	int rc;
+	int display = lsm_task_display(current);
 
 	lsmblob_init(blob, 0);
 	hlist_for_each_entry(hp, &security_hook_heads.secctx_to_secid, list) {
 		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
 			continue;
-		rc = hp->hook.secctx_to_secid(secdata, seclen,
-					      &blob->secid[hp->lsmid->slot]);
-		if (rc != 0)
-			return rc;
+		if (display == LSMBLOB_INVALID || display == hp->lsmid->slot)
+			return hp->hook.secctx_to_secid(secdata, seclen,
+						&blob->secid[hp->lsmid->slot]);
 	}
 	return 0;
 }
@@ -2038,7 +2137,15 @@ EXPORT_SYMBOL(security_secctx_to_secid);
 
 void security_release_secctx(char *secdata, u32 seclen)
 {
-	call_void_hook(release_secctx, secdata, seclen);
+	struct security_hook_list *hp;
+	int *display = current->security;
+
+	hlist_for_each_entry(hp, &security_hook_heads.release_secctx, list)
+		if (display == NULL || *display == LSMBLOB_INVALID ||
+		    *display == hp->lsmid->slot) {
+			hp->hook.release_secctx(secdata, seclen);
+			return;
+		}
 }
 EXPORT_SYMBOL(security_release_secctx);
 
@@ -2163,8 +2270,15 @@ EXPORT_SYMBOL(security_sock_rcv_skb);
 int security_socket_getpeersec_stream(struct socket *sock, char __user *optval,
 				      int __user *optlen, unsigned len)
 {
-	return call_int_hook(socket_getpeersec_stream, -ENOPROTOOPT, sock,
-				optval, optlen, len);
+	int display = lsm_task_display(current);
+	struct security_hook_list *hp;
+
+	hlist_for_each_entry(hp, &security_hook_heads.socket_getpeersec_stream,
+			     list)
+		if (display == LSMBLOB_INVALID || display == hp->lsmid->slot)
+			return hp->hook.socket_getpeersec_stream(sock, optval,
+								 optlen, len);
+	return -ENOPROTOOPT;
 }
 
 int security_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb,
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 13/28] LSM: Use lsmblob in security_cred_getsecid
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

Change the security_cred_getsecid() interface to fill in a
lsmblob instead of a u32 secid. The associated data elements
in the audit sub-system are changed from a secid to a lsmblob
to accommodate multiple possible LSM audit users.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 include/linux/security.h          |  2 +-
 kernel/audit.c                    | 14 +++++-------
 kernel/audit.h                    |  5 +++--
 kernel/auditsc.c                  | 37 +++++++++++--------------------
 security/integrity/ima/ima_main.c |  8 +++----
 security/security.c               | 12 +++++++---
 6 files changed, 36 insertions(+), 42 deletions(-)

diff --git a/include/linux/security.h b/include/linux/security.h
index 2d81cac418e3..d310fa3942ce 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -387,7 +387,7 @@ int security_cred_alloc_blank(struct cred *cred, gfp_t gfp);
 void security_cred_free(struct cred *cred);
 int security_prepare_creds(struct cred *new, const struct cred *old, gfp_t gfp);
 void security_transfer_creds(struct cred *new, const struct cred *old);
-void security_cred_getsecid(const struct cred *c, u32 *secid);
+void security_cred_getsecid(const struct cred *c, struct lsmblob *blob);
 int security_kernel_act_as(struct cred *new, struct lsmblob *blob);
 int security_kernel_create_files_as(struct cred *new, struct inode *inode);
 int security_kernel_module_request(char *kmod_name);
diff --git a/kernel/audit.c b/kernel/audit.c
index a0205f3c23c7..1b51e907f131 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -137,7 +137,7 @@ static u32	audit_backlog_wait_time = AUDIT_BACKLOG_WAIT_TIME;
 /* The identity of the user shutting down the audit system. */
 kuid_t		audit_sig_uid = INVALID_UID;
 pid_t		audit_sig_pid = -1;
-u32		audit_sig_sid = 0;
+struct lsmblob	audit_sig_lsm;
 
 /* Records can be lost in several ways:
    0) [suppressed in audit_alloc]
@@ -1429,23 +1429,21 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	}
 	case AUDIT_SIGNAL_INFO:
 		len = 0;
-		if (audit_sig_sid) {
-			struct lsmblob blob;
-
-			lsmblob_init(&blob, audit_sig_sid);
-			err = security_secid_to_secctx(&blob, &ctx, &len);
+		if (lsmblob_is_set(&audit_sig_lsm)) {
+			err = security_secid_to_secctx(&audit_sig_lsm, &ctx,
+						       &len);
 			if (err)
 				return err;
 		}
 		sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
 		if (!sig_data) {
-			if (audit_sig_sid)
+			if (lsmblob_is_set(&audit_sig_lsm))
 				security_release_secctx(ctx, len);
 			return -ENOMEM;
 		}
 		sig_data->uid = from_kuid(&init_user_ns, audit_sig_uid);
 		sig_data->pid = audit_sig_pid;
-		if (audit_sig_sid) {
+		if (lsmblob_is_set(&audit_sig_lsm)) {
 			memcpy(sig_data->ctx, ctx, len);
 			security_release_secctx(ctx, len);
 		}
diff --git a/kernel/audit.h b/kernel/audit.h
index 958d5b8fc1b3..29e29c6f4afb 100644
--- a/kernel/audit.h
+++ b/kernel/audit.h
@@ -22,6 +22,7 @@
 #include <linux/fs.h>
 #include <linux/audit.h>
 #include <linux/skbuff.h>
+#include <linux/security.h>
 #include <uapi/linux/mqueue.h>
 #include <linux/tty.h>
 
@@ -147,7 +148,7 @@ struct audit_context {
 	kuid_t		    target_auid;
 	kuid_t		    target_uid;
 	unsigned int	    target_sessionid;
-	u32		    target_sid;
+	struct lsmblob   target_lsm;
 	char		    target_comm[TASK_COMM_LEN];
 
 	struct audit_tree_refs *trees, *first_trees;
@@ -338,7 +339,7 @@ extern char *audit_unpack_string(void **bufp, size_t *remain, size_t len);
 
 extern pid_t audit_sig_pid;
 extern kuid_t audit_sig_uid;
-extern u32 audit_sig_sid;
+extern struct lsmblob audit_sig_lsm;
 
 extern int audit_filter(int msgtype, unsigned int listtype);
 
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 54797c0fc3b7..c7aa39bda5cc 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -112,7 +112,7 @@ struct audit_aux_data_pids {
 	kuid_t			target_auid[AUDIT_AUX_PIDS];
 	kuid_t			target_uid[AUDIT_AUX_PIDS];
 	unsigned int		target_sessionid[AUDIT_AUX_PIDS];
-	u32			target_sid[AUDIT_AUX_PIDS];
+	struct lsmblob	target_lsm[AUDIT_AUX_PIDS];
 	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
 	int			pid_count;
 };
@@ -938,14 +938,14 @@ static inline void audit_free_context(struct audit_context *context)
 }
 
 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
-				 kuid_t auid, kuid_t uid, unsigned int sessionid,
-				 u32 sid, char *comm)
+				 kuid_t auid, kuid_t uid,
+				 unsigned int sessionid,
+				 struct lsmblob *blob, char *comm)
 {
 	struct audit_buffer *ab;
 	char *ctx = NULL;
 	u32 len;
 	int rc = 0;
-	struct lsmblob blob;
 
 	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
 	if (!ab)
@@ -954,9 +954,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
 			 from_kuid(&init_user_ns, auid),
 			 from_kuid(&init_user_ns, uid), sessionid);
-	if (sid) {
-		lsmblob_init(&blob, sid);
-		if (security_secid_to_secctx(&blob, &ctx, &len)) {
+	if (lsmblob_is_set(blob)) {
+		if (security_secid_to_secctx(blob, &ctx, &len)) {
 			audit_log_format(ab, " obj=(none)");
 			rc = 1;
 		} else {
@@ -1527,7 +1526,7 @@ static void audit_log_exit(void)
 						  axs->target_auid[i],
 						  axs->target_uid[i],
 						  axs->target_sessionid[i],
-						  axs->target_sid[i],
+						  &axs->target_lsm[i],
 						  axs->target_comm[i]))
 				call_panic = 1;
 	}
@@ -1536,7 +1535,7 @@ static void audit_log_exit(void)
 	    audit_log_pid_context(context, context->target_pid,
 				  context->target_auid, context->target_uid,
 				  context->target_sessionid,
-				  context->target_sid, context->target_comm))
+				  &context->target_lsm, context->target_comm))
 			call_panic = 1;
 
 	if (context->pwd.dentry && context->pwd.mnt) {
@@ -1713,7 +1712,7 @@ void __audit_syscall_exit(int success, long return_code)
 	context->aux = NULL;
 	context->aux_pids = NULL;
 	context->target_pid = 0;
-	context->target_sid = 0;
+	lsmblob_init(&context->target_lsm, 0);
 	context->sockaddr_len = 0;
 	context->type = 0;
 	context->fds[0] = -1;
@@ -2367,15 +2366,12 @@ int __audit_sockaddr(int len, void *a)
 void __audit_ptrace(struct task_struct *t)
 {
 	struct audit_context *context = audit_context();
-	struct lsmblob blob;
 
 	context->target_pid = task_tgid_nr(t);
 	context->target_auid = audit_get_loginuid(t);
 	context->target_uid = task_uid(t);
 	context->target_sessionid = audit_get_sessionid(t);
-	security_task_getsecid(t, &blob);
-	/* scaffolding - until target_sid is converted */
-	context->target_sid = blob.secid[0];
+	security_task_getsecid(t, &context->target_lsm);
 	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
 }
 
@@ -2392,7 +2388,6 @@ int audit_signal_info(int sig, struct task_struct *t)
 	struct audit_aux_data_pids *axp;
 	struct audit_context *ctx = audit_context();
 	kuid_t uid = current_uid(), auid, t_uid = task_uid(t);
-	struct lsmblob blob;
 
 	if (auditd_test_task(t) &&
 	    (sig == SIGTERM || sig == SIGHUP ||
@@ -2403,9 +2398,7 @@ int audit_signal_info(int sig, struct task_struct *t)
 			audit_sig_uid = auid;
 		else
 			audit_sig_uid = uid;
-		security_task_getsecid(current, &blob);
-		/* scaffolding until audit_sig_sid is converted */
-		audit_sig_sid = blob.secid[0];
+		security_task_getsecid(current, &audit_sig_lsm);
 	}
 
 	if (!audit_signals || audit_dummy_context())
@@ -2418,9 +2411,7 @@ int audit_signal_info(int sig, struct task_struct *t)
 		ctx->target_auid = audit_get_loginuid(t);
 		ctx->target_uid = t_uid;
 		ctx->target_sessionid = audit_get_sessionid(t);
-		security_task_getsecid(t, &blob);
-		/* scaffolding until target_sid is converted */
-		ctx->target_sid = blob.secid[0];
+		security_task_getsecid(t, &ctx->target_lsm);
 		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
 		return 0;
 	}
@@ -2441,9 +2432,7 @@ int audit_signal_info(int sig, struct task_struct *t)
 	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
 	axp->target_uid[axp->pid_count] = t_uid;
 	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
-	security_task_getsecid(t, &blob);
-	/* scaffolding until target_sid is converted */
-	axp->target_sid[axp->pid_count] = blob.secid[0];
+	security_task_getsecid(t, &axp->target_lsm[axp->pid_count]);
 	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
 	axp->pid_count++;
 
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index fefa848cf0c7..1afb75a893af 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -363,7 +363,6 @@ int ima_file_mmap(struct file *file, unsigned long prot)
 int ima_bprm_check(struct linux_binprm *bprm)
 {
 	int ret;
-	u32 secid;
 	struct lsmblob blob;
 
 	security_task_getsecid(current, &blob);
@@ -373,9 +372,10 @@ int ima_bprm_check(struct linux_binprm *bprm)
 	if (ret)
 		return ret;
 
-	security_cred_getsecid(bprm->cred, &secid);
-	return process_measurement(bprm->file, bprm->cred, secid, NULL, 0,
-				   MAY_EXEC, CREDS_CHECK);
+	security_cred_getsecid(bprm->cred, &blob);
+	/* scaffolding until process_measurement changes */
+	return process_measurement(bprm->file, bprm->cred, blob.secid[0],
+				   NULL, 0, MAY_EXEC, CREDS_CHECK);
 }
 
 /**
diff --git a/security/security.c b/security/security.c
index 745e8791b6e3..8927508b2142 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1627,10 +1627,16 @@ void security_transfer_creds(struct cred *new, const struct cred *old)
 	call_void_hook(cred_transfer, new, old);
 }
 
-void security_cred_getsecid(const struct cred *c, u32 *secid)
+void security_cred_getsecid(const struct cred *c, struct lsmblob *blob)
 {
-	*secid = 0;
-	call_void_hook(cred_getsecid, c, secid);
+	struct security_hook_list *hp;
+
+	lsmblob_init(blob, 0);
+	hlist_for_each_entry(hp, &security_hook_heads.cred_getsecid, list) {
+		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+			continue;
+		hp->hook.cred_getsecid(c, &blob->secid[hp->lsmid->slot]);
+	}
 }
 EXPORT_SYMBOL(security_cred_getsecid);
 
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 14/28] IMA: Change internal interfaces to use lsmblobs
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

The IMA interfaces ima_get_action() and ima_match_policy()
call LSM functions that use lsmblobs. Change the IMA functions
to pass the lsmblob to be compatible with the LSM functions.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 security/integrity/ima/ima.h          | 10 ++++++----
 security/integrity/ima/ima_api.c      |  9 +++++----
 security/integrity/ima/ima_appraise.c |  4 +---
 security/integrity/ima/ima_main.c     | 27 +++++++++++----------------
 security/integrity/ima/ima_policy.c   | 12 ++++++------
 5 files changed, 29 insertions(+), 33 deletions(-)

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 5a337239d9e4..73b3b15dec5c 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -192,8 +192,9 @@ enum ima_hooks {
 };
 
 /* LIM API function definitions */
-int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
-		   int mask, enum ima_hooks func, int *pcr);
+int ima_get_action(struct inode *inode, const struct cred *cred,
+		   struct lsmblob *blob, int mask, enum ima_hooks func,
+		   int *pcr);
 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
 int ima_collect_measurement(struct integrity_iint_cache *iint,
 			    struct file *file, void *buf, loff_t size,
@@ -213,8 +214,9 @@ void ima_free_template_entry(struct ima_template_entry *entry);
 const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
 
 /* IMA policy related functions */
-int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
-		     enum ima_hooks func, int mask, int flags, int *pcr);
+int ima_match_policy(struct inode *inode, const struct cred *cred,
+		     struct lsmblob *blob, enum ima_hooks func, int mask,
+		     int flags, int *pcr);
 void ima_init_policy(void);
 void ima_update_policy(void);
 void ima_update_policy_flag(void);
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index c7505fb122d4..94b2a4840d81 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -159,7 +159,7 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
  * ima_get_action - appraise & measure decision based on policy.
  * @inode: pointer to inode to measure
  * @cred: pointer to credentials structure to validate
- * @secid: secid of the task being validated
+ * @blob: LSM data of the task being validated
  * @mask: contains the permission mask (MAY_READ, MAY_WRITE, MAY_EXEC,
  *        MAY_APPEND)
  * @func: caller identifier
@@ -175,14 +175,15 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
  * Returns IMA_MEASURE, IMA_APPRAISE mask.
  *
  */
-int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
-		   int mask, enum ima_hooks func, int *pcr)
+int ima_get_action(struct inode *inode, const struct cred *cred,
+		   struct lsmblob *blob, int mask, enum ima_hooks func,
+		   int *pcr)
 {
 	int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE | IMA_HASH;
 
 	flags &= ima_policy_flag;
 
-	return ima_match_policy(inode, cred, secid, func, mask, flags, pcr);
+	return ima_match_policy(inode, cred, blob, func, mask, flags, pcr);
 }
 
 /*
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 85c7692fc4a3..3ff7aae81829 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -50,15 +50,13 @@ bool is_ima_appraise_enabled(void)
  */
 int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
 {
-	u32 secid;
 	struct lsmblob blob;
 
 	if (!ima_appraise)
 		return 0;
 
 	security_task_getsecid(current, &blob);
-	lsmblob_secid(&blob, &secid);
-	return ima_match_policy(inode, current_cred(), secid, func, mask,
+	return ima_match_policy(inode, current_cred(), &blob, func, mask,
 				IMA_APPRAISE | IMA_HASH, NULL);
 }
 
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index 1afb75a893af..0588dd9a88db 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -169,8 +169,8 @@ void ima_file_free(struct file *file)
 }
 
 static int process_measurement(struct file *file, const struct cred *cred,
-			       u32 secid, char *buf, loff_t size, int mask,
-			       enum ima_hooks func)
+			       struct lsmblob *blob, char *buf, loff_t size,
+			       int mask, enum ima_hooks func)
 {
 	struct inode *inode = file_inode(file);
 	struct integrity_iint_cache *iint = NULL;
@@ -192,7 +192,7 @@ static int process_measurement(struct file *file, const struct cred *cred,
 	 * bitmask based on the appraise/audit/measurement policy.
 	 * Included is the appraise submask.
 	 */
-	action = ima_get_action(inode, cred, secid, mask, func, &pcr);
+	action = ima_get_action(inode, cred, blob, mask, func, &pcr);
 	violation_check = ((func == FILE_CHECK || func == MMAP_CHECK) &&
 			   (ima_policy_flag & IMA_MEASURE));
 	if (!action && !violation_check)
@@ -339,8 +339,7 @@ int ima_file_mmap(struct file *file, unsigned long prot)
 
 	if (file && (prot & PROT_EXEC)) {
 		security_task_getsecid(current, &blob);
-		/* scaffolding - until process_measurement changes */
-		return process_measurement(file, current_cred(), blob.secid[0],
+		return process_measurement(file, current_cred(), &blob,
 					   NULL, 0, MAY_EXEC, MMAP_CHECK);
 	}
 
@@ -366,16 +365,14 @@ int ima_bprm_check(struct linux_binprm *bprm)
 	struct lsmblob blob;
 
 	security_task_getsecid(current, &blob);
-	/* scaffolding until process_measurement changes */
-	ret = process_measurement(bprm->file, current_cred(), blob.secid[0],
-				  NULL, 0, MAY_EXEC, BPRM_CHECK);
+	ret = process_measurement(bprm->file, current_cred(), &blob, NULL, 0,
+				  MAY_EXEC, BPRM_CHECK);
 	if (ret)
 		return ret;
 
 	security_cred_getsecid(bprm->cred, &blob);
-	/* scaffolding until process_measurement changes */
-	return process_measurement(bprm->file, bprm->cred, blob.secid[0],
-				   NULL, 0, MAY_EXEC, CREDS_CHECK);
+	return process_measurement(bprm->file, bprm->cred, &blob, NULL, 0,
+				   MAY_EXEC, CREDS_CHECK);
 }
 
 /**
@@ -393,8 +390,7 @@ int ima_file_check(struct file *file, int mask)
 	struct lsmblob blob;
 
 	security_task_getsecid(current, &blob);
-	/* scaffolding until process_measurement changes */
-	return process_measurement(file, current_cred(), blob.secid[0], NULL, 0,
+	return process_measurement(file, current_cred(), &blob, NULL, 0,
 				   mask & (MAY_READ | MAY_WRITE | MAY_EXEC |
 					   MAY_APPEND), FILE_CHECK);
 }
@@ -526,9 +522,8 @@ int ima_post_read_file(struct file *file, void *buf, loff_t size,
 
 	func = read_idmap[read_id] ?: FILE_CHECK;
 	security_task_getsecid(current, &blob);
-	/* scaffolding until process_measurement changes */
-	return process_measurement(file, current_cred(), blob.secid[0], buf,
-				   size, MAY_READ, func);
+	return process_measurement(file, current_cred(), &blob, buf, size,
+				   MAY_READ, func);
 }
 
 /**
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 92ee3d984c73..dbad256aa7b4 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -286,7 +286,7 @@ static void ima_lsm_update_rules(void)
  * Returns true on rule match, false on failure.
  */
 static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
-			    const struct cred *cred, u32 secid,
+			    const struct cred *cred, struct lsmblob *blob,
 			    enum ima_hooks func, int mask)
 {
 	int i;
@@ -345,7 +345,6 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
 		case LSM_SUBJ_USER:
 		case LSM_SUBJ_ROLE:
 		case LSM_SUBJ_TYPE:
-			lsmblob_init(&blob, secid);
 			rc = security_filter_rule_match(&blob,
 							rule->lsm[i].type,
 							Audit_equal,
@@ -394,7 +393,7 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
  * @inode: pointer to an inode for which the policy decision is being made
  * @cred: pointer to a credentials structure for which the policy decision is
  *        being made
- * @secid: LSM secid of the task to be validated
+ * @blob: LSM data of the task to be validated
  * @func: IMA hook identifier
  * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
  * @pcr: set the pcr to extend
@@ -406,8 +405,9 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
  * list when walking it.  Reads are many orders of magnitude more numerous
  * than writes so ima_match_policy() is classical RCU candidate.
  */
-int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
-		     enum ima_hooks func, int mask, int flags, int *pcr)
+int ima_match_policy(struct inode *inode, const struct cred *cred,
+		     struct lsmblob *blob, enum ima_hooks func, int mask,
+		     int flags, int *pcr)
 {
 	struct ima_rule_entry *entry;
 	int action = 0, actmask = flags | (flags << 1);
@@ -418,7 +418,7 @@ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
 		if (!(entry->action & actmask))
 			continue;
 
-		if (!ima_match_rules(entry, inode, cred, secid, func, mask))
+		if (!ima_match_rules(entry, inode, cred, blob, func, mask))
 			continue;
 
 		action |= entry->flags & IMA_ACTION_FLAGS;
-- 
2.20.1


^ permalink raw reply related

* [PATCH v8 10/28] LSM: Use lsmblob in security_ipc_getsecid
From: Casey Schaufler @ 2019-08-29 23:29 UTC (permalink / raw)
  To: casey.schaufler, jmorris, linux-security-module, selinux
  Cc: casey, keescook, john.johansen, penguin-kernel, paul, sds
In-Reply-To: <20190829232935.7099-1-casey@schaufler-ca.com>

There may be more than one LSM that provides IPC data
for auditing. Change security_ipc_getsecid() to fill in
a lsmblob structure instead of the u32 secid. The
audit data structure containing the secid will be updated
later, so there is a bit of scaffolding here.

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 include/linux/security.h |  7 ++++---
 kernel/auditsc.c         |  5 ++++-
 security/security.c      | 12 +++++++++---
 3 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/include/linux/security.h b/include/linux/security.h
index 7b4667cc4930..41dc3053094e 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -417,7 +417,7 @@ int security_task_prctl(int option, unsigned long arg2, unsigned long arg3,
 			unsigned long arg4, unsigned long arg5);
 void security_task_to_inode(struct task_struct *p, struct inode *inode);
 int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag);
-void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid);
+void security_ipc_getsecid(struct kern_ipc_perm *ipcp, struct lsmblob *blob);
 int security_msg_msg_alloc(struct msg_msg *msg);
 void security_msg_msg_free(struct msg_msg *msg);
 int security_msg_queue_alloc(struct kern_ipc_perm *msq);
@@ -1102,9 +1102,10 @@ static inline int security_ipc_permission(struct kern_ipc_perm *ipcp,
 	return 0;
 }
 
-static inline void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
+static inline void security_ipc_getsecid(struct kern_ipc_perm *ipcp,
+					 struct lsmblob *blob)
 {
-	*secid = 0;
+	lsmblob_init(blob, 0);
 }
 
 static inline int security_msg_msg_alloc(struct msg_msg *msg)
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index d31914088a82..148733ec3c72 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -2268,11 +2268,14 @@ void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
 void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
 {
 	struct audit_context *context = audit_context();
+	struct lsmblob blob;
 	context->ipc.uid = ipcp->uid;
 	context->ipc.gid = ipcp->gid;
 	context->ipc.mode = ipcp->mode;
 	context->ipc.has_perm = 0;
-	security_ipc_getsecid(ipcp, &context->ipc.osid);
+	security_ipc_getsecid(ipcp, &blob);
+	/* scaffolding on the [0] - change "osid" to a lsmblob */
+	context->ipc.osid = blob.secid[0];
 	context->type = AUDIT_IPC;
 }
 
diff --git a/security/security.c b/security/security.c
index 837c3c6b6e7c..b4789c31e532 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1795,10 +1795,16 @@ int security_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
 	return call_int_hook(ipc_permission, 0, ipcp, flag);
 }
 
-void security_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
+void security_ipc_getsecid(struct kern_ipc_perm *ipcp, struct lsmblob *blob)
 {
-	*secid = 0;
-	call_void_hook(ipc_getsecid, ipcp, secid);
+	struct security_hook_list *hp;
+
+	lsmblob_init(blob, 0);
+	hlist_for_each_entry(hp, &security_hook_heads.ipc_getsecid, list) {
+		if (WARN_ON(hp->lsmid->slot < 0 || hp->lsmid->slot >= lsm_slot))
+			continue;
+		hp->hook.ipc_getsecid(ipcp, &blob->secid[hp->lsmid->slot]);
+	}
 }
 
 int security_msg_msg_alloc(struct msg_msg *msg)
-- 
2.20.1


^ permalink raw reply related


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