[PATCH v11 00/11] LSM: Three basic syscalls

[PATCH v11 00/11] LSM: Three basic syscalls

[Casey Schaufler]

Add three system calls for the Linux Security Module ABI.

lsm_get_self_attr() provides the security module specific attributes
that have previously been visible in the /proc/self/attr directory.
For each security module that uses the specified attribute on the
current process the system call will return an LSM identifier and
the value of the attribute. The LSM and attribute identifier values
are defined in include/uapi/linux/lsm.h

LSM identifiers are simple integers and reflect the order in which
the LSM was added to the mainline kernel. This is a convention, not
a promise of the API. LSM identifiers below the value of 100 are
reserved for unspecified future uses. That could include information
about the security infrastructure itself, or about how multiple LSMs
might interact with each other.

A new LSM hook security_getselfattr() is introduced to get the
required information from the security modules. This is similar
to the existing security_getprocattr() hook, but specifies the
format in which string data is returned and requires the module
to put the information into a userspace destination.

lsm_set_self_attr() changes the specified LSM attribute. Only one
attribute can be changed at a time, and then only if the specified
security module allows the change.

A new LSM hook security_setselfattr() is introduced to set the
required information in the security modules. This is similar
to the existing security_setprocattr() hook, but specifies the
format in which string data is presented and requires the module
to get the information from a userspace destination.

lsm_list_modules() provides the LSM identifiers, in order, of the
security modules that are active on the system. This has been
available in the securityfs file /sys/kernel/security/lsm.

Patch 0001 changes the LSM registration from passing the name
of the module to passing a lsm_id structure that contains the
name of the module, an LSM identifier number and an attribute
identifier.
Patch 0002 adds the registered lsm_ids to a table.
Patch 0003 changes security_[gs]etprocattr() to use LSM IDs instead
of LSM names.
Patch 0004 implements lsm_get_self_attr() and lsm_set_self_attr().
New LSM hooks security_getselfattr() and security_setselfattr() are
defined.
Patch 0005 implements lsm_list_modules().
Patch 0006 wires up the syscalls.
Patch 0007 implements helper functions to make it easier for
security modules to use lsm_ctx structures.
Patch 0008 provides the Smack implementation for [gs]etselfattr().
Patch 0009 provides the AppArmor implementation for [gs]etselfattr().
Patch 0010 provides the SELinux implementation for [gs]etselfattr().
Patch 0011 implements selftests for the three new syscalls.

https://github.com/cschaufler/lsm-stacking.git#lsm-syscalls-6.4-rc1-v11

v11: Remove redundent alignment code
     Improve a few comments.
     Use LSM_ATTR_UNDEF in place of 0 in a few places.
     Correct a return of -EINVAL to -E2BIG.
v10: Correct use of __user.
     Improve a few comments.
     Revert unnecessary changes in module initialization.
v9: Support a flag LSM_FLAG_SINGLE in lsm_get_self_attr() that
    instructs the call to provide only the attribute for the LSM
    identified in the referenced lsm_ctx structure.
    Fix a typing error.
    Change some coding style.
v8: Allow an LSM to provide more than one instance of an attribute,
    even though none of the existing modules do so.
    Pad the data returned by lsm_get_self_attr() to the size of
    the struct lsm_ctx.
    Change some displeasing varilable names.
v7: Pass the attribute desired to lsm_[gs]et_self_attr in its own
    parameter rather than encoding it in the flags.
    Change the flags parameters to u32.
    Don't shortcut out of calling LSM specific code in the
    infrastructure, let the LSM report that doesn't support an
    attribute instead. With that it is not necessary to maintain
    a set of supported attributes in the lsm_id structure.
    Fix a typing error.
v6: Switch from reusing security_[gs]procattr() to using new
    security_[gs]selfattr() hooks. Use explicit sized data types
    in the lsm_ctx structure.

v5: Correct syscall parameter data types.

v4: Restore "reserved" LSM ID values. Add explaination.
    Squash patches that introduce fields in lsm_id.
    Correct a wireup error.

v3: Add lsm_set_self_attr().
    Rename lsm_self_attr() to lsm_get_self_attr().
    Provide the values only for a specifed attribute in
    lsm_get_self_attr().
    Add selftests for the three new syscalls.
    Correct some parameter checking.

v2: Use user-interface safe data types.
    Remove "reserved" LSM ID values.
    Improve kerneldoc comments
    Include copyright dates
    Use more descriptive name for LSM counter
    Add documentation
    Correct wireup errors


Casey Schaufler (11):
  LSM: Identify modules by more than name
  LSM: Maintain a table of LSM attribute data
  proc: Use lsmids instead of lsm names for attrs
  LSM: syscalls for current process attributes
  LSM: Create lsm_list_modules system call
  LSM: wireup Linux Security Module syscalls
  LSM: Helpers for attribute names and filling lsm_ctx
  Smack: implement setselfattr and getselfattr hooks
  AppArmor: Add selfattr hooks
  SELinux: Add selfattr hooks
  LSM: selftests for Linux Security Module syscalls

 Documentation/userspace-api/index.rst         |   1 +
 Documentation/userspace-api/lsm.rst           |  73 +++++
 MAINTAINERS                                   |   1 +
 arch/alpha/kernel/syscalls/syscall.tbl        |   3 +
 arch/arm/tools/syscall.tbl                    |   3 +
 arch/arm64/include/asm/unistd.h               |   2 +-
 arch/arm64/include/asm/unistd32.h             |   6 +
 arch/ia64/kernel/syscalls/syscall.tbl         |   3 +
 arch/m68k/kernel/syscalls/syscall.tbl         |   3 +
 arch/microblaze/kernel/syscalls/syscall.tbl   |   3 +
 arch/mips/kernel/syscalls/syscall_n32.tbl     |   3 +
 arch/mips/kernel/syscalls/syscall_n64.tbl     |   3 +
 arch/mips/kernel/syscalls/syscall_o32.tbl     |   3 +
 arch/parisc/kernel/syscalls/syscall.tbl       |   3 +
 arch/powerpc/kernel/syscalls/syscall.tbl      |   3 +
 arch/s390/kernel/syscalls/syscall.tbl         |   3 +
 arch/sh/kernel/syscalls/syscall.tbl           |   3 +
 arch/sparc/kernel/syscalls/syscall.tbl        |   3 +
 arch/x86/entry/syscalls/syscall_32.tbl        |   3 +
 arch/x86/entry/syscalls/syscall_64.tbl        |   3 +
 arch/xtensa/kernel/syscalls/syscall.tbl       |   3 +
 fs/proc/base.c                                |  29 +-
 fs/proc/internal.h                            |   2 +-
 include/linux/lsm_hook_defs.h                 |   4 +
 include/linux/lsm_hooks.h                     |  17 +-
 include/linux/security.h                      |  46 ++-
 include/linux/syscalls.h                      |   6 +
 include/uapi/asm-generic/unistd.h             |  11 +-
 include/uapi/linux/lsm.h                      |  90 ++++++
 kernel/sys_ni.c                               |   5 +
 security/Makefile                             |   1 +
 security/apparmor/include/procattr.h          |   2 +-
 security/apparmor/lsm.c                       | 110 ++++++-
 security/apparmor/procattr.c                  |  10 +-
 security/bpf/hooks.c                          |   9 +-
 security/commoncap.c                          |   8 +-
 security/landlock/cred.c                      |   2 +-
 security/landlock/fs.c                        |   2 +-
 security/landlock/ptrace.c                    |   2 +-
 security/landlock/setup.c                     |   6 +
 security/landlock/setup.h                     |   1 +
 security/loadpin/loadpin.c                    |   9 +-
 security/lockdown/lockdown.c                  |   8 +-
 security/lsm_syscalls.c                       | 118 ++++++++
 security/safesetid/lsm.c                      |   9 +-
 security/security.c                           | 215 +++++++++++++-
 security/selinux/hooks.c                      | 157 ++++++++--
 security/smack/smack_lsm.c                    | 114 +++++++-
 security/tomoyo/tomoyo.c                      |   9 +-
 security/yama/yama_lsm.c                      |   8 +-
 .../arch/mips/entry/syscalls/syscall_n64.tbl  |   3 +
 .../arch/powerpc/entry/syscalls/syscall.tbl   |   3 +
 .../perf/arch/s390/entry/syscalls/syscall.tbl |   3 +
 .../arch/x86/entry/syscalls/syscall_64.tbl    |   3 +
 tools/testing/selftests/Makefile              |   1 +
 tools/testing/selftests/lsm/Makefile          |  12 +
 tools/testing/selftests/lsm/config            |   2 +
 .../selftests/lsm/lsm_get_self_attr_test.c    | 270 ++++++++++++++++++
 .../selftests/lsm/lsm_list_modules_test.c     | 153 ++++++++++
 .../selftests/lsm/lsm_set_self_attr_test.c    |  70 +++++
 60 files changed, 1568 insertions(+), 93 deletions(-)
 create mode 100644 Documentation/userspace-api/lsm.rst
 create mode 100644 include/uapi/linux/lsm.h
 create mode 100644 security/lsm_syscalls.c
 create mode 100644 tools/testing/selftests/lsm/Makefile
 create mode 100644 tools/testing/selftests/lsm/config
 create mode 100644 tools/testing/selftests/lsm/lsm_get_self_attr_test.c
 create mode 100644 tools/testing/selftests/lsm/lsm_list_modules_test.c
 create mode 100644 tools/testing/selftests/lsm/lsm_set_self_attr_test.c

-- 
2.40.1

[PATCH v11 01/11] LSM: Identify modules by more than name

[Casey Schaufler]

Create a struct lsm_id to contain identifying information
about Linux Security Modules (LSMs). At inception this contains
the name of the module, an identifier associated with the security
module and an integer member "attrs" which identifies the API
related data associated with each security module. The initial set
of features maps to information that has traditionaly been available
in /proc/self/attr. They are documented in a new userspace-api file.
Change the security_add_hooks() interface to use this structure.
Change the individual modules to maintain their own struct lsm_id
and pass it to security_add_hooks().

The values are for LSM identifiers are defined in a new UAPI
header file linux/lsm.h. Each existing LSM has been updated to
include it's LSMID in the lsm_id.

The LSM ID values are sequential, with the oldest module
LSM_ID_CAPABILITY being the lowest value and the existing modules
numbered in the order they were included in the main line kernel.
This is an arbitrary convention for assigning the values, but
none better presents itself. The value 0 is defined as being invalid.
The values 1-99 are reserved for any special case uses which may
arise in the future. This may include attributes of the LSM
infrastructure itself, possibly related to namespacing or network
attribute management. A special range is identified for such attributes
to help reduce confusion for developers unfamiliar with LSMs.

LSM attribute values are defined for the attributes presented by
modules that are available today. As with the LSM IDs, The value 0
is defined as being invalid. The values 1-99 are reserved for any
special case uses which may arise in the future.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: linux-security-module <linux-security-module@vger.kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
---
 Documentation/userspace-api/index.rst |  1 +
 Documentation/userspace-api/lsm.rst   | 55 +++++++++++++++++++++++++++
 MAINTAINERS                           |  1 +
 include/linux/lsm_hooks.h             | 16 +++++++-
 include/uapi/linux/lsm.h              | 54 ++++++++++++++++++++++++++
 security/apparmor/lsm.c               |  8 +++-
 security/bpf/hooks.c                  |  9 ++++-
 security/commoncap.c                  |  8 +++-
 security/landlock/cred.c              |  2 +-
 security/landlock/fs.c                |  2 +-
 security/landlock/ptrace.c            |  2 +-
 security/landlock/setup.c             |  6 +++
 security/landlock/setup.h             |  1 +
 security/loadpin/loadpin.c            |  9 ++++-
 security/lockdown/lockdown.c          |  8 +++-
 security/safesetid/lsm.c              |  9 ++++-
 security/security.c                   | 12 +++---
 security/selinux/hooks.c              |  9 ++++-
 security/smack/smack_lsm.c            |  8 +++-
 security/tomoyo/tomoyo.c              |  9 ++++-
 security/yama/yama_lsm.c              |  8 +++-
 21 files changed, 216 insertions(+), 21 deletions(-)
 create mode 100644 Documentation/userspace-api/lsm.rst
 create mode 100644 include/uapi/linux/lsm.h

diff --git a/Documentation/userspace-api/index.rst b/Documentation/userspace-api/index.rst
index 72a65db0c498..b5fa29c077eb 100644
--- a/Documentation/userspace-api/index.rst
+++ b/Documentation/userspace-api/index.rst
@@ -32,6 +32,7 @@ place where this information is gathered.
    sysfs-platform_profile
    vduse
    futex2
+   lsm
 
 .. only::  subproject and html
 
diff --git a/Documentation/userspace-api/lsm.rst b/Documentation/userspace-api/lsm.rst
new file mode 100644
index 000000000000..6ddf5506110b
--- /dev/null
+++ b/Documentation/userspace-api/lsm.rst
@@ -0,0 +1,55 @@
+.. SPDX-License-Identifier: GPL-2.0
+.. Copyright (C) 2022 Casey Schaufler <casey@schaufler-ca.com>
+.. Copyright (C) 2022 Intel Corporation
+
+=====================================
+Linux Security Modules
+=====================================
+
+:Author: Casey Schaufler
+:Date: November 2022
+
+Linux security modules (LSM) provide a mechanism to implement
+additional access controls to the Linux security policies.
+
+The various security modules may support any of these attributes:
+
+``LSM_ATTR_CURRENT`` is the current, active security context of the
+process.
+The proc filesystem provides this value in ``/proc/self/attr/current``.
+This is supported by the SELinux, Smack and AppArmor security modules.
+Smack also provides this value in ``/proc/self/attr/smack/current``.
+AppArmor also provides this value in ``/proc/self/attr/apparmor/current``.
+
+``LSM_ATTR_EXEC`` is the security context of the process at the time the
+current image was executed.
+The proc filesystem provides this value in ``/proc/self/attr/exec``.
+This is supported by the SELinux and AppArmor security modules.
+AppArmor also provides this value in ``/proc/self/attr/apparmor/exec``.
+
+``LSM_ATTR_FSCREATE`` is the security context of the process used when
+creating file system objects.
+The proc filesystem provides this value in ``/proc/self/attr/fscreate``.
+This is supported by the SELinux security module.
+
+``LSM_ATTR_KEYCREATE`` is the security context of the process used when
+creating key objects.
+The proc filesystem provides this value in ``/proc/self/attr/keycreate``.
+This is supported by the SELinux security module.
+
+``LSM_ATTR_PREV`` is the security context of the process at the time the
+current security context was set.
+The proc filesystem provides this value in ``/proc/self/attr/prev``.
+This is supported by the SELinux and AppArmor security modules.
+AppArmor also provides this value in ``/proc/self/attr/apparmor/prev``.
+
+``LSM_ATTR_SOCKCREATE`` is the security context of the process used when
+creating socket objects.
+The proc filesystem provides this value in ``/proc/self/attr/sockcreate``.
+This is supported by the SELinux security module.
+
+Additional documentation
+========================
+
+* Documentation/security/lsm.rst
+* Documentation/security/lsm-development.rst
diff --git a/MAINTAINERS b/MAINTAINERS
index 7e0b87d5aa2e..5e326a6355a3 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -18965,6 +18965,7 @@ S:	Supported
 W:	http://kernsec.org/
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm.git
 F:	security/
+F:	include/uapi/linux/lsm.h
 X:	security/selinux/
 
 SELINUX SECURITY MODULE
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index ab2b2fafa4a4..fba8881d2bb5 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -41,6 +41,18 @@ struct security_hook_heads {
 	#undef LSM_HOOK
 } __randomize_layout;
 
+/**
+ * struct lsm_id - Identify a Linux Security Module.
+ * @lsm: name of the LSM, must be approved by the LSM maintainers
+ * @id: LSM ID number from uapi/linux/lsm.h
+ *
+ * Contains the information that identifies the LSM.
+ */
+struct lsm_id {
+	const char	*name;
+	u64		id;
+};
+
 /*
  * Security module hook list structure.
  * For use with generic list macros for common operations.
@@ -49,7 +61,7 @@ struct security_hook_list {
 	struct hlist_node		list;
 	struct hlist_head		*head;
 	union security_list_options	hook;
-	const char			*lsm;
+	struct lsm_id			*lsmid;
 } __randomize_layout;
 
 /*
@@ -84,7 +96,7 @@ extern struct security_hook_heads security_hook_heads;
 extern char *lsm_names;
 
 extern void security_add_hooks(struct security_hook_list *hooks, int count,
-				const char *lsm);
+			       struct lsm_id *lsmid);
 
 #define LSM_FLAG_LEGACY_MAJOR	BIT(0)
 #define LSM_FLAG_EXCLUSIVE	BIT(1)
diff --git a/include/uapi/linux/lsm.h b/include/uapi/linux/lsm.h
new file mode 100644
index 000000000000..f27c9a9cc376
--- /dev/null
+++ b/include/uapi/linux/lsm.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Linux Security Modules (LSM) - User space API
+ *
+ * Copyright (C) 2022 Casey Schaufler <casey@schaufler-ca.com>
+ * Copyright (C) 2022 Intel Corporation
+ */
+
+#ifndef _UAPI_LINUX_LSM_H
+#define _UAPI_LINUX_LSM_H
+
+/*
+ * ID tokens to identify Linux Security Modules (LSMs)
+ *
+ * These token values are used to uniquely identify specific LSMs
+ * in the kernel as well as in the kernel's LSM userspace API.
+ *
+ * A value of zero/0 is considered undefined and should not be used
+ * outside the kernel. Values 1-99 are reserved for potential
+ * future use.
+ */
+#define LSM_ID_UNDEF		0
+#define LSM_ID_CAPABILITY	100
+#define LSM_ID_SELINUX		101
+#define LSM_ID_SMACK		102
+#define LSM_ID_TOMOYO		103
+#define LSM_ID_IMA		104
+#define LSM_ID_APPARMOR		105
+#define LSM_ID_YAMA		106
+#define LSM_ID_LOADPIN		107
+#define LSM_ID_SAFESETID	108
+#define LSM_ID_LOCKDOWN		109
+#define LSM_ID_BPF		110
+#define LSM_ID_LANDLOCK		111
+
+/*
+ * LSM_ATTR_XXX definitions identify different LSM attributes
+ * which are used in the kernel's LSM userspace API. Support
+ * for these attributes vary across the different LSMs. None
+ * are required.
+ *
+ * A value of zero/0 is considered undefined and should not be used
+ * outside the kernel. Values 1-99 are reserved for potential
+ * future use.
+ */
+#define LSM_ATTR_UNDEF		0
+#define LSM_ATTR_CURRENT	100
+#define LSM_ATTR_EXEC		101
+#define LSM_ATTR_FSCREATE	102
+#define LSM_ATTR_KEYCREATE	103
+#define LSM_ATTR_PREV		104
+#define LSM_ATTR_SOCKCREATE	105
+
+#endif /* _UAPI_LINUX_LSM_H */
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index f431251ffb91..308cb3a281c3 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -24,6 +24,7 @@
 #include <linux/zstd.h>
 #include <net/sock.h>
 #include <uapi/linux/mount.h>
+#include <uapi/linux/lsm.h>
 
 #include "include/apparmor.h"
 #include "include/apparmorfs.h"
@@ -1215,6 +1216,11 @@ struct lsm_blob_sizes apparmor_blob_sizes __ro_after_init = {
 	.lbs_task = sizeof(struct aa_task_ctx),
 };
 
+static struct lsm_id apparmor_lsmid __ro_after_init = {
+	.name = "apparmor",
+	.id = LSM_ID_APPARMOR,
+};
+
 static struct security_hook_list apparmor_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
 	LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
@@ -1904,7 +1910,7 @@ static int __init apparmor_init(void)
 		goto buffers_out;
 	}
 	security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
-				"apparmor");
+				&apparmor_lsmid);
 
 	/* Report that AppArmor successfully initialized */
 	apparmor_initialized = 1;
diff --git a/security/bpf/hooks.c b/security/bpf/hooks.c
index cfaf1d0e6a5f..7e7bdc1b7979 100644
--- a/security/bpf/hooks.c
+++ b/security/bpf/hooks.c
@@ -5,6 +5,7 @@
  */
 #include <linux/lsm_hooks.h>
 #include <linux/bpf_lsm.h>
+#include <uapi/linux/lsm.h>
 
 static struct security_hook_list bpf_lsm_hooks[] __ro_after_init = {
 	#define LSM_HOOK(RET, DEFAULT, NAME, ...) \
@@ -15,9 +16,15 @@ static struct security_hook_list bpf_lsm_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(task_free, bpf_task_storage_free),
 };
 
+static struct lsm_id bpf_lsmid __ro_after_init = {
+	.name = "bpf",
+	.id = LSM_ID_BPF,
+};
+
 static int __init bpf_lsm_init(void)
 {
-	security_add_hooks(bpf_lsm_hooks, ARRAY_SIZE(bpf_lsm_hooks), "bpf");
+	security_add_hooks(bpf_lsm_hooks, ARRAY_SIZE(bpf_lsm_hooks),
+			   &bpf_lsmid);
 	pr_info("LSM support for eBPF active\n");
 	return 0;
 }
diff --git a/security/commoncap.c b/security/commoncap.c
index 0b3fc2f3afe7..44c2577105f7 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -25,6 +25,7 @@
 #include <linux/binfmts.h>
 #include <linux/personality.h>
 #include <linux/mnt_idmapping.h>
+#include <uapi/linux/lsm.h>
 
 /*
  * If a non-root user executes a setuid-root binary in
@@ -1440,6 +1441,11 @@ int cap_mmap_file(struct file *file, unsigned long reqprot,
 
 #ifdef CONFIG_SECURITY
 
+static struct lsm_id capability_lsmid __ro_after_init = {
+	.name = "capability",
+	.id = LSM_ID_CAPABILITY,
+};
+
 static struct security_hook_list capability_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(capable, cap_capable),
 	LSM_HOOK_INIT(settime, cap_settime),
@@ -1464,7 +1470,7 @@ static struct security_hook_list capability_hooks[] __ro_after_init = {
 static int __init capability_init(void)
 {
 	security_add_hooks(capability_hooks, ARRAY_SIZE(capability_hooks),
-				"capability");
+			   &capability_lsmid);
 	return 0;
 }
 
diff --git a/security/landlock/cred.c b/security/landlock/cred.c
index 13dff2a31545..786af18c4a1c 100644
--- a/security/landlock/cred.c
+++ b/security/landlock/cred.c
@@ -42,5 +42,5 @@ static struct security_hook_list landlock_hooks[] __ro_after_init = {
 __init void landlock_add_cred_hooks(void)
 {
 	security_add_hooks(landlock_hooks, ARRAY_SIZE(landlock_hooks),
-			   LANDLOCK_NAME);
+			   &landlock_lsmid);
 }
diff --git a/security/landlock/fs.c b/security/landlock/fs.c
index 1c0c198f6fdb..db5ebecfbf02 100644
--- a/security/landlock/fs.c
+++ b/security/landlock/fs.c
@@ -1307,5 +1307,5 @@ static struct security_hook_list landlock_hooks[] __ro_after_init = {
 __init void landlock_add_fs_hooks(void)
 {
 	security_add_hooks(landlock_hooks, ARRAY_SIZE(landlock_hooks),
-			   LANDLOCK_NAME);
+			   &landlock_lsmid);
 }
diff --git a/security/landlock/ptrace.c b/security/landlock/ptrace.c
index 8a06d6c492bf..2bfc533d36e4 100644
--- a/security/landlock/ptrace.c
+++ b/security/landlock/ptrace.c
@@ -116,5 +116,5 @@ static struct security_hook_list landlock_hooks[] __ro_after_init = {
 __init void landlock_add_ptrace_hooks(void)
 {
 	security_add_hooks(landlock_hooks, ARRAY_SIZE(landlock_hooks),
-			   LANDLOCK_NAME);
+			   &landlock_lsmid);
 }
diff --git a/security/landlock/setup.c b/security/landlock/setup.c
index 0f6113528fa4..f5ec82a1c381 100644
--- a/security/landlock/setup.c
+++ b/security/landlock/setup.c
@@ -8,6 +8,7 @@
 
 #include <linux/init.h>
 #include <linux/lsm_hooks.h>
+#include <uapi/linux/lsm.h>
 
 #include "common.h"
 #include "cred.h"
@@ -24,6 +25,11 @@ struct lsm_blob_sizes landlock_blob_sizes __ro_after_init = {
 	.lbs_superblock = sizeof(struct landlock_superblock_security),
 };
 
+struct lsm_id landlock_lsmid __ro_after_init = {
+	.name = LANDLOCK_NAME,
+	.id = LSM_ID_LANDLOCK,
+};
+
 static int __init landlock_init(void)
 {
 	landlock_add_cred_hooks();
diff --git a/security/landlock/setup.h b/security/landlock/setup.h
index 1daffab1ab4b..38bce5b172dc 100644
--- a/security/landlock/setup.h
+++ b/security/landlock/setup.h
@@ -14,5 +14,6 @@
 extern bool landlock_initialized;
 
 extern struct lsm_blob_sizes landlock_blob_sizes;
+extern struct lsm_id landlock_lsmid;
 
 #endif /* _SECURITY_LANDLOCK_SETUP_H */
diff --git a/security/loadpin/loadpin.c b/security/loadpin/loadpin.c
index ebae964f7cc9..14202ee4a362 100644
--- a/security/loadpin/loadpin.c
+++ b/security/loadpin/loadpin.c
@@ -20,6 +20,7 @@
 #include <linux/string_helpers.h>
 #include <linux/dm-verity-loadpin.h>
 #include <uapi/linux/loadpin.h>
+#include <uapi/linux/lsm.h>
 
 #define VERITY_DIGEST_FILE_HEADER "# LOADPIN_TRUSTED_VERITY_ROOT_DIGESTS"
 
@@ -208,6 +209,11 @@ static int loadpin_load_data(enum kernel_load_data_id id, bool contents)
 	return loadpin_check(NULL, (enum kernel_read_file_id) id);
 }
 
+static struct lsm_id loadpin_lsmid __ro_after_init = {
+	.name = "loadpin",
+	.id = LSM_ID_LOADPIN,
+};
+
 static struct security_hook_list loadpin_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(sb_free_security, loadpin_sb_free_security),
 	LSM_HOOK_INIT(kernel_read_file, loadpin_read_file),
@@ -259,7 +265,8 @@ static int __init loadpin_init(void)
 	if (!register_sysctl("kernel/loadpin", loadpin_sysctl_table))
 		pr_notice("sysctl registration failed!\n");
 #endif
-	security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks), "loadpin");
+	security_add_hooks(loadpin_hooks, ARRAY_SIZE(loadpin_hooks),
+			   &loadpin_lsmid);
 
 	return 0;
 }
diff --git a/security/lockdown/lockdown.c b/security/lockdown/lockdown.c
index 68d19632aeb7..aa109b5811d9 100644
--- a/security/lockdown/lockdown.c
+++ b/security/lockdown/lockdown.c
@@ -13,6 +13,7 @@
 #include <linux/security.h>
 #include <linux/export.h>
 #include <linux/lsm_hooks.h>
+#include <uapi/linux/lsm.h>
 
 static enum lockdown_reason kernel_locked_down;
 
@@ -75,6 +76,11 @@ static struct security_hook_list lockdown_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(locked_down, lockdown_is_locked_down),
 };
 
+static struct lsm_id lockdown_lsmid __ro_after_init = {
+	.name = "lockdown",
+	.id = LSM_ID_LOCKDOWN,
+};
+
 static int __init lockdown_lsm_init(void)
 {
 #if defined(CONFIG_LOCK_DOWN_KERNEL_FORCE_INTEGRITY)
@@ -83,7 +89,7 @@ static int __init lockdown_lsm_init(void)
 	lock_kernel_down("Kernel configuration", LOCKDOWN_CONFIDENTIALITY_MAX);
 #endif
 	security_add_hooks(lockdown_hooks, ARRAY_SIZE(lockdown_hooks),
-			   "lockdown");
+			   &lockdown_lsmid);
 	return 0;
 }
 
diff --git a/security/safesetid/lsm.c b/security/safesetid/lsm.c
index e806739f7868..24bbab457623 100644
--- a/security/safesetid/lsm.c
+++ b/security/safesetid/lsm.c
@@ -19,6 +19,7 @@
 #include <linux/ptrace.h>
 #include <linux/sched/task_stack.h>
 #include <linux/security.h>
+#include <uapi/linux/lsm.h>
 #include "lsm.h"
 
 /* Flag indicating whether initialization completed */
@@ -261,6 +262,11 @@ static int safesetid_task_fix_setgroups(struct cred *new, const struct cred *old
 	return 0;
 }
 
+static struct lsm_id safesetid_lsmid __ro_after_init = {
+	.name = "safesetid",
+	.id = LSM_ID_SAFESETID,
+};
+
 static struct security_hook_list safesetid_security_hooks[] = {
 	LSM_HOOK_INIT(task_fix_setuid, safesetid_task_fix_setuid),
 	LSM_HOOK_INIT(task_fix_setgid, safesetid_task_fix_setgid),
@@ -271,7 +277,8 @@ static struct security_hook_list safesetid_security_hooks[] = {
 static int __init safesetid_security_init(void)
 {
 	security_add_hooks(safesetid_security_hooks,
-			   ARRAY_SIZE(safesetid_security_hooks), "safesetid");
+			   ARRAY_SIZE(safesetid_security_hooks),
+			   &safesetid_lsmid);
 
 	/* Report that SafeSetID successfully initialized */
 	safesetid_initialized = 1;
diff --git a/security/security.c b/security/security.c
index d5ff7ff45b77..e56714ef045a 100644
--- a/security/security.c
+++ b/security/security.c
@@ -512,17 +512,17 @@ static int lsm_append(const char *new, char **result)
  * security_add_hooks - Add a modules hooks to the hook lists.
  * @hooks: the hooks to add
  * @count: the number of hooks to add
- * @lsm: the name of the security module
+ * @lsmid: the identification information for the security module
  *
  * Each LSM has to register its hooks with the infrastructure.
  */
 void __init security_add_hooks(struct security_hook_list *hooks, int count,
-			       const char *lsm)
+			       struct lsm_id *lsmid)
 {
 	int i;
 
 	for (i = 0; i < count; i++) {
-		hooks[i].lsm = lsm;
+		hooks[i].lsmid = lsmid;
 		hlist_add_tail_rcu(&hooks[i].list, hooks[i].head);
 	}
 
@@ -531,7 +531,7 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count,
 	 * and fix this up afterwards.
 	 */
 	if (slab_is_available()) {
-		if (lsm_append(lsm, &lsm_names) < 0)
+		if (lsm_append(lsmid->name, &lsm_names) < 0)
 			panic("%s - Cannot get early memory.\n", __func__);
 	}
 }
@@ -3778,7 +3778,7 @@ int security_getprocattr(struct task_struct *p, const char *lsm,
 	struct security_hook_list *hp;
 
 	hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
-		if (lsm != NULL && strcmp(lsm, hp->lsm))
+		if (lsm != NULL && strcmp(lsm, hp->lsmid->name))
 			continue;
 		return hp->hook.getprocattr(p, name, value);
 	}
@@ -3803,7 +3803,7 @@ int security_setprocattr(const char *lsm, const char *name, void *value,
 	struct security_hook_list *hp;
 
 	hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
-		if (lsm != NULL && strcmp(lsm, hp->lsm))
+		if (lsm != NULL && strcmp(lsm, hp->lsmid->name))
 			continue;
 		return hp->hook.setprocattr(name, value, size);
 	}
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 79b4890e9936..49ec74bc006c 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -92,6 +92,7 @@
 #include <linux/fsnotify.h>
 #include <linux/fanotify.h>
 #include <linux/io_uring.h>
+#include <uapi/linux/lsm.h>
 
 #include "avc.h"
 #include "objsec.h"
@@ -6890,6 +6891,11 @@ static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
 }
 #endif /* CONFIG_IO_URING */
 
+static struct lsm_id selinux_lsmid __ro_after_init = {
+	.name = "selinux",
+	.id = LSM_ID_SELINUX,
+};
+
 /*
  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
  * 1. any hooks that don't belong to (2.) or (3.) below,
@@ -7210,7 +7216,8 @@ static __init int selinux_init(void)
 
 	hashtab_cache_init();
 
-	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
+	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
+			   &selinux_lsmid);
 
 	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
 		panic("SELinux: Unable to register AVC netcache callback\n");
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 7a3e9ab137d8..cf847cfe5ed8 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -43,6 +43,7 @@
 #include <linux/fs_parser.h>
 #include <linux/watch_queue.h>
 #include <linux/io_uring.h>
+#include <uapi/linux/lsm.h>
 #include "smack.h"
 
 #define TRANS_TRUE	"TRUE"
@@ -4840,6 +4841,11 @@ struct lsm_blob_sizes smack_blob_sizes __ro_after_init = {
 	.lbs_superblock = sizeof(struct superblock_smack),
 };
 
+static struct lsm_id smack_lsmid __ro_after_init = {
+	.name = "smack",
+	.id = LSM_ID_SMACK,
+};
+
 static struct security_hook_list smack_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(ptrace_access_check, smack_ptrace_access_check),
 	LSM_HOOK_INIT(ptrace_traceme, smack_ptrace_traceme),
@@ -5046,7 +5052,7 @@ static __init int smack_init(void)
 	/*
 	 * Register with LSM
 	 */
-	security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), "smack");
+	security_add_hooks(smack_hooks, ARRAY_SIZE(smack_hooks), &smack_lsmid);
 	smack_enabled = 1;
 
 	pr_info("Smack:  Initializing.\n");
diff --git a/security/tomoyo/tomoyo.c b/security/tomoyo/tomoyo.c
index 25006fddc964..e2efc94ec481 100644
--- a/security/tomoyo/tomoyo.c
+++ b/security/tomoyo/tomoyo.c
@@ -6,6 +6,7 @@
  */
 
 #include <linux/lsm_hooks.h>
+#include <uapi/linux/lsm.h>
 #include "common.h"
 
 /**
@@ -542,6 +543,11 @@ static void tomoyo_task_free(struct task_struct *task)
 	}
 }
 
+static struct lsm_id tomoyo_lsmid __ro_after_init = {
+	.name = "tomoyo",
+	.id = LSM_ID_TOMOYO,
+};
+
 /*
  * tomoyo_security_ops is a "struct security_operations" which is used for
  * registering TOMOYO.
@@ -595,7 +601,8 @@ static int __init tomoyo_init(void)
 	struct tomoyo_task *s = tomoyo_task(current);
 
 	/* register ourselves with the security framework */
-	security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks), "tomoyo");
+	security_add_hooks(tomoyo_hooks, ARRAY_SIZE(tomoyo_hooks),
+			   &tomoyo_lsmid);
 	pr_info("TOMOYO Linux initialized\n");
 	s->domain_info = &tomoyo_kernel_domain;
 	atomic_inc(&tomoyo_kernel_domain.users);
diff --git a/security/yama/yama_lsm.c b/security/yama/yama_lsm.c
index 2503cf153d4a..31b52685e041 100644
--- a/security/yama/yama_lsm.c
+++ b/security/yama/yama_lsm.c
@@ -18,6 +18,7 @@
 #include <linux/task_work.h>
 #include <linux/sched.h>
 #include <linux/spinlock.h>
+#include <uapi/linux/lsm.h>
 
 #define YAMA_SCOPE_DISABLED	0
 #define YAMA_SCOPE_RELATIONAL	1
@@ -421,6 +422,11 @@ static int yama_ptrace_traceme(struct task_struct *parent)
 	return rc;
 }
 
+static struct lsm_id yama_lsmid __ro_after_init = {
+	.name = "yama",
+	.id = LSM_ID_YAMA,
+};
+
 static struct security_hook_list yama_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(ptrace_access_check, yama_ptrace_access_check),
 	LSM_HOOK_INIT(ptrace_traceme, yama_ptrace_traceme),
@@ -471,7 +477,7 @@ static inline void yama_init_sysctl(void) { }
 static int __init yama_init(void)
 {
 	pr_info("Yama: becoming mindful.\n");
-	security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks), "yama");
+	security_add_hooks(yama_hooks, ARRAY_SIZE(yama_hooks), &yama_lsmid);
 	yama_init_sysctl();
 	return 0;
 }
-- 
2.40.1

[PATCH v11 02/11] LSM: Maintain a table of LSM attribute data

[Casey Schaufler]

As LSMs are registered add their lsm_id pointers to a table.
This will be used later for attribute reporting.

Determine the number of possible security modules based on
their respective CONFIG options. This allows the number to be
known at build time. This allows data structures and tables
to use the constant.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
---
 include/linux/security.h |  2 ++
 security/security.c      | 36 ++++++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+)

diff --git a/include/linux/security.h b/include/linux/security.h
index e2734e9e44d5..569b1d8ab002 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -138,6 +138,8 @@ enum lockdown_reason {
 };
 
 extern const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1];
+extern u32 lsm_active_cnt;
+extern struct lsm_id *lsm_idlist[];
 
 /* These functions are in security/commoncap.c */
 extern int cap_capable(const struct cred *cred, struct user_namespace *ns,
diff --git a/security/security.c b/security/security.c
index e56714ef045a..39c5225603cf 100644
--- a/security/security.c
+++ b/security/security.c
@@ -36,6 +36,25 @@
 /* How many LSMs were built into the kernel? */
 #define LSM_COUNT (__end_lsm_info - __start_lsm_info)
 
+/*
+ * How many LSMs are built into the kernel as determined at
+ * build time. Used to determine fixed array sizes.
+ * The capability module is accounted for by CONFIG_SECURITY
+ */
+#define LSM_CONFIG_COUNT ( \
+	(IS_ENABLED(CONFIG_SECURITY) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_SECURITY_SELINUX) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_SECURITY_SMACK) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_SECURITY_TOMOYO) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_IMA) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_SECURITY_APPARMOR) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_SECURITY_YAMA) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_SECURITY_LOADPIN) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_SECURITY_SAFESETID) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_SECURITY_LOCKDOWN_LSM) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_BPF_LSM) ? 1 : 0) + \
+	(IS_ENABLED(CONFIG_SECURITY_LANDLOCK) ? 1 : 0))
+
 /*
  * These are descriptions of the reasons that can be passed to the
  * security_locked_down() LSM hook. Placing this array here allows
@@ -245,6 +264,12 @@ static void __init initialize_lsm(struct lsm_info *lsm)
 	}
 }
 
+/*
+ * Current index to use while initializing the lsm id list.
+ */
+u32 lsm_active_cnt __ro_after_init;
+struct lsm_id *lsm_idlist[LSM_CONFIG_COUNT] __ro_after_init;
+
 /* Populate ordered LSMs list from comma-separated LSM name list. */
 static void __init ordered_lsm_parse(const char *order, const char *origin)
 {
@@ -521,6 +546,17 @@ void __init security_add_hooks(struct security_hook_list *hooks, int count,
 {
 	int i;
 
+	if (lsm_active_cnt >= LSM_CONFIG_COUNT)
+		panic("%s Too many LSMs registered.\n", __func__);
+	/*
+	 * A security module may call security_add_hooks() more
+	 * than once during initialization, and LSM initialization
+	 * is serialized. Landlock is one such case.
+	 * Look at the previous entry, if there is one, for duplication.
+	 */
+	if (lsm_active_cnt == 0 || lsm_idlist[lsm_active_cnt - 1] != lsmid)
+		lsm_idlist[lsm_active_cnt++] = lsmid;
+
 	for (i = 0; i < count; i++) {
 		hooks[i].lsmid = lsmid;
 		hlist_add_tail_rcu(&hooks[i].list, hooks[i].head);
-- 
2.40.1

[PATCH v11 03/11] proc: Use lsmids instead of lsm names for attrs

[Casey Schaufler]

Use the LSM ID number instead of the LSM name to identify which
security module's attibute data should be shown in /proc/self/attr.
The security_[gs]etprocattr() functions have been changed to expect
the LSM ID. The change from a string comparison to an integer comparison
in these functions will provide a minor performance improvement.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Cc: linux-fsdevel@vger.kernel.org
---
 fs/proc/base.c           | 29 +++++++++++++++--------------
 fs/proc/internal.h       |  2 +-
 include/linux/security.h | 11 +++++------
 security/security.c      | 15 +++++++--------
 4 files changed, 28 insertions(+), 29 deletions(-)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index 05452c3b9872..f999bb5c497b 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -97,6 +97,7 @@
 #include <linux/resctrl.h>
 #include <linux/cn_proc.h>
 #include <linux/ksm.h>
+#include <uapi/linux/lsm.h>
 #include <trace/events/oom.h>
 #include "internal.h"
 #include "fd.h"
@@ -146,10 +147,10 @@ struct pid_entry {
 	NOD(NAME, (S_IFREG|(MODE)),			\
 		NULL, &proc_single_file_operations,	\
 		{ .proc_show = show } )
-#define ATTR(LSM, NAME, MODE)				\
+#define ATTR(LSMID, NAME, MODE)				\
 	NOD(NAME, (S_IFREG|(MODE)),			\
 		NULL, &proc_pid_attr_operations,	\
-		{ .lsm = LSM })
+		{ .lsmid = LSMID })
 
 /*
  * Count the number of hardlinks for the pid_entry table, excluding the .
@@ -2730,7 +2731,7 @@ static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
 	if (!task)
 		return -ESRCH;
 
-	length = security_getprocattr(task, PROC_I(inode)->op.lsm,
+	length = security_getprocattr(task, PROC_I(inode)->op.lsmid,
 				      file->f_path.dentry->d_name.name,
 				      &p);
 	put_task_struct(task);
@@ -2788,7 +2789,7 @@ static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
 	if (rv < 0)
 		goto out_free;
 
-	rv = security_setprocattr(PROC_I(inode)->op.lsm,
+	rv = security_setprocattr(PROC_I(inode)->op.lsmid,
 				  file->f_path.dentry->d_name.name, page,
 				  count);
 	mutex_unlock(&current->signal->cred_guard_mutex);
@@ -2837,27 +2838,27 @@ static const struct inode_operations proc_##LSM##_attr_dir_inode_ops = { \
 
 #ifdef CONFIG_SECURITY_SMACK
 static const struct pid_entry smack_attr_dir_stuff[] = {
-	ATTR("smack", "current",	0666),
+	ATTR(LSM_ID_SMACK, "current",	0666),
 };
 LSM_DIR_OPS(smack);
 #endif
 
 #ifdef CONFIG_SECURITY_APPARMOR
 static const struct pid_entry apparmor_attr_dir_stuff[] = {
-	ATTR("apparmor", "current",	0666),
-	ATTR("apparmor", "prev",	0444),
-	ATTR("apparmor", "exec",	0666),
+	ATTR(LSM_ID_APPARMOR, "current",	0666),
+	ATTR(LSM_ID_APPARMOR, "prev",		0444),
+	ATTR(LSM_ID_APPARMOR, "exec",		0666),
 };
 LSM_DIR_OPS(apparmor);
 #endif
 
 static const struct pid_entry attr_dir_stuff[] = {
-	ATTR(NULL, "current",		0666),
-	ATTR(NULL, "prev",		0444),
-	ATTR(NULL, "exec",		0666),
-	ATTR(NULL, "fscreate",		0666),
-	ATTR(NULL, "keycreate",		0666),
-	ATTR(NULL, "sockcreate",	0666),
+	ATTR(LSM_ID_UNDEF, "current",	0666),
+	ATTR(LSM_ID_UNDEF, "prev",		0444),
+	ATTR(LSM_ID_UNDEF, "exec",		0666),
+	ATTR(LSM_ID_UNDEF, "fscreate",	0666),
+	ATTR(LSM_ID_UNDEF, "keycreate",	0666),
+	ATTR(LSM_ID_UNDEF, "sockcreate",	0666),
 #ifdef CONFIG_SECURITY_SMACK
 	DIR("smack",			0555,
 	    proc_smack_attr_dir_inode_ops, proc_smack_attr_dir_ops),
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index 9dda7e54b2d0..a889d9ef9584 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -92,7 +92,7 @@ union proc_op {
 	int (*proc_show)(struct seq_file *m,
 		struct pid_namespace *ns, struct pid *pid,
 		struct task_struct *task);
-	const char *lsm;
+	int lsmid;
 };
 
 struct proc_inode {
diff --git a/include/linux/security.h b/include/linux/security.h
index 569b1d8ab002..945101b0d404 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -470,10 +470,9 @@ int security_sem_semctl(struct kern_ipc_perm *sma, int cmd);
 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops,
 			unsigned nsops, int alter);
 void security_d_instantiate(struct dentry *dentry, struct inode *inode);
-int security_getprocattr(struct task_struct *p, const char *lsm, const char *name,
+int security_getprocattr(struct task_struct *p, int lsmid, const char *name,
 			 char **value);
-int security_setprocattr(const char *lsm, const char *name, void *value,
-			 size_t size);
+int security_setprocattr(int lsmid, 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(u32 secid, char **secdata, u32 *seclen);
@@ -1332,14 +1331,14 @@ static inline void security_d_instantiate(struct dentry *dentry,
 					  struct inode *inode)
 { }
 
-static inline int security_getprocattr(struct task_struct *p, const char *lsm,
+static inline int security_getprocattr(struct task_struct *p, int lsmid,
 				       const char *name, char **value)
 {
 	return -EINVAL;
 }
 
-static inline int security_setprocattr(const char *lsm, char *name,
-				       void *value, size_t size)
+static inline int security_setprocattr(int lsmid, char *name, void *value,
+				       size_t size)
 {
 	return -EINVAL;
 }
diff --git a/security/security.c b/security/security.c
index 39c5225603cf..501c0884ec03 100644
--- a/security/security.c
+++ b/security/security.c
@@ -3800,7 +3800,7 @@ EXPORT_SYMBOL(security_d_instantiate);
 /**
  * security_getprocattr() - Read an attribute for a task
  * @p: the task
- * @lsm: LSM name
+ * @lsmid: LSM identification
  * @name: attribute name
  * @value: attribute value
  *
@@ -3808,13 +3808,13 @@ EXPORT_SYMBOL(security_d_instantiate);
  *
  * Return: Returns the length of @value on success, a negative value otherwise.
  */
-int security_getprocattr(struct task_struct *p, const char *lsm,
-			 const char *name, char **value)
+int security_getprocattr(struct task_struct *p, int lsmid, const char *name,
+			 char **value)
 {
 	struct security_hook_list *hp;
 
 	hlist_for_each_entry(hp, &security_hook_heads.getprocattr, list) {
-		if (lsm != NULL && strcmp(lsm, hp->lsmid->name))
+		if (lsmid != 0 && lsmid != hp->lsmid->id)
 			continue;
 		return hp->hook.getprocattr(p, name, value);
 	}
@@ -3823,7 +3823,7 @@ int security_getprocattr(struct task_struct *p, const char *lsm,
 
 /**
  * security_setprocattr() - Set an attribute for a task
- * @lsm: LSM name
+ * @lsmid: LSM identification
  * @name: attribute name
  * @value: attribute value
  * @size: attribute value size
@@ -3833,13 +3833,12 @@ int security_getprocattr(struct task_struct *p, const char *lsm,
  *
  * Return: Returns bytes written on success, a negative value otherwise.
  */
-int security_setprocattr(const char *lsm, const char *name, void *value,
-			 size_t size)
+int security_setprocattr(int lsmid, const char *name, void *value, size_t size)
 {
 	struct security_hook_list *hp;
 
 	hlist_for_each_entry(hp, &security_hook_heads.setprocattr, list) {
-		if (lsm != NULL && strcmp(lsm, hp->lsmid->name))
+		if (lsmid != 0 && lsmid != hp->lsmid->id)
 			continue;
 		return hp->hook.setprocattr(name, value, size);
 	}
-- 
2.40.1

[PATCH v11 04/11] LSM: syscalls for current process attributes

[Casey Schaufler]

Create a system call lsm_get_self_attr() to provide the security
module maintained attributes of the current process.
Create a system call lsm_set_self_attr() to set a security
module maintained attribute of the current process.
Historically these attributes have been exposed to user space via
entries in procfs under /proc/self/attr.

The attribute value is provided in a lsm_ctx structure. The structure
identifies the size of the attribute, and the attribute value. The format
of the attribute value is defined by the security module. A flags field
is included for LSM specific information. It is currently unused and must
be 0. The total size of the data, including the lsm_ctx structure and any
padding, is maintained as well.

struct lsm_ctx {
        __u64 id;
        __u64 flags;
        __u64 len;
        __u64 ctx_len;
        __u8 ctx[];
};

Two new LSM hooks are used to interface with the LSMs.
security_getselfattr() collects the lsm_ctx values from the
LSMs that support the hook, accounting for space requirements.
security_setselfattr() identifies which LSM the attribute is
intended for and passes it along.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
---
 Documentation/userspace-api/lsm.rst |  15 ++++
 include/linux/lsm_hook_defs.h       |   4 +
 include/linux/lsm_hooks.h           |   1 +
 include/linux/security.h            |  19 +++++
 include/linux/syscalls.h            |   5 ++
 include/uapi/linux/lsm.h            |  36 +++++++++
 kernel/sys_ni.c                     |   4 +
 security/Makefile                   |   1 +
 security/lsm_syscalls.c             |  55 ++++++++++++++
 security/security.c                 | 112 ++++++++++++++++++++++++++++
 10 files changed, 252 insertions(+)
 create mode 100644 security/lsm_syscalls.c

diff --git a/Documentation/userspace-api/lsm.rst b/Documentation/userspace-api/lsm.rst
index 6ddf5506110b..e6c3f262addc 100644
--- a/Documentation/userspace-api/lsm.rst
+++ b/Documentation/userspace-api/lsm.rst
@@ -48,6 +48,21 @@ creating socket objects.
 The proc filesystem provides this value in ``/proc/self/attr/sockcreate``.
 This is supported by the SELinux security module.
 
+Kernel interface
+================
+
+Set a security attribute of the current process
+-----------------------------------------------
+
+.. kernel-doc:: security/lsm_syscalls.c
+    :identifiers: sys_lsm_set_self_attr
+
+Get the specified security attributes of the current process
+------------------------------------------------------------
+
+.. kernel-doc:: security/lsm_syscalls.c
+    :identifiers: sys_lsm_get_self_attr
+
 Additional documentation
 ========================
 
diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h
index 6bb55e61e8e8..f69a7863dbe2 100644
--- a/include/linux/lsm_hook_defs.h
+++ b/include/linux/lsm_hook_defs.h
@@ -261,6 +261,10 @@ LSM_HOOK(int, 0, sem_semop, struct kern_ipc_perm *perm, struct sembuf *sops,
 LSM_HOOK(int, 0, netlink_send, struct sock *sk, struct sk_buff *skb)
 LSM_HOOK(void, LSM_RET_VOID, d_instantiate, struct dentry *dentry,
 	 struct inode *inode)
+LSM_HOOK(int, -EOPNOTSUPP, getselfattr, unsigned int attr,
+	 struct lsm_ctx __user *ctx, size_t *size, u32 flags)
+LSM_HOOK(int, -EOPNOTSUPP, setselfattr, unsigned int attr,
+	 struct lsm_ctx __user *ctx, size_t size, u32 flags)
 LSM_HOOK(int, -EINVAL, getprocattr, struct task_struct *p, const char *name,
 	 char **value)
 LSM_HOOK(int, -EINVAL, setprocattr, const char *name, void *value, size_t size)
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index fba8881d2bb5..9a3ae6b33d7b 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -25,6 +25,7 @@
 #ifndef __LINUX_LSM_HOOKS_H
 #define __LINUX_LSM_HOOKS_H
 
+#include <uapi/linux/lsm.h>
 #include <linux/security.h>
 #include <linux/init.h>
 #include <linux/rculist.h>
diff --git a/include/linux/security.h b/include/linux/security.h
index 945101b0d404..475d0abfebda 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -60,6 +60,7 @@ struct fs_parameter;
 enum fs_value_type;
 struct watch;
 struct watch_notification;
+struct lsm_ctx;
 
 /* Default (no) options for the capable function */
 #define CAP_OPT_NONE 0x0
@@ -470,6 +471,10 @@ int security_sem_semctl(struct kern_ipc_perm *sma, int cmd);
 int security_sem_semop(struct kern_ipc_perm *sma, struct sembuf *sops,
 			unsigned nsops, int alter);
 void security_d_instantiate(struct dentry *dentry, struct inode *inode);
+int security_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
+			 size_t __user *size, u32 flags);
+int security_setselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
+			 size_t size, u32 flags);
 int security_getprocattr(struct task_struct *p, int lsmid, const char *name,
 			 char **value);
 int security_setprocattr(int lsmid, const char *name, void *value, size_t size);
@@ -1331,6 +1336,20 @@ static inline void security_d_instantiate(struct dentry *dentry,
 					  struct inode *inode)
 { }
 
+static inline int security_getselfattr(unsigned int attr,
+				       struct lsm_ctx __user *ctx,
+				       size_t __user *size, u32 flags)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int security_setselfattr(unsigned int attr,
+				       struct lsm_ctx __user *ctx,
+				       size_t size, u32 flags)
+{
+	return -EOPNOTSUPP;
+}
+
 static inline int security_getprocattr(struct task_struct *p, int lsmid,
 				       const char *name, char **value)
 {
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 33a0ee3bcb2e..9a94c31bf6b6 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -71,6 +71,7 @@ struct clone_args;
 struct open_how;
 struct mount_attr;
 struct landlock_ruleset_attr;
+struct lsm_ctx;
 enum landlock_rule_type;
 
 #include <linux/types.h>
@@ -1058,6 +1059,10 @@ asmlinkage long sys_memfd_secret(unsigned int flags);
 asmlinkage long sys_set_mempolicy_home_node(unsigned long start, unsigned long len,
 					    unsigned long home_node,
 					    unsigned long flags);
+asmlinkage long sys_lsm_get_self_attr(unsigned int attr, struct lsm_ctx *ctx,
+				      size_t *size, __u32 flags);
+asmlinkage long sys_lsm_set_self_attr(unsigned int attr, struct lsm_ctx *ctx,
+				      size_t size, __u32 flags);
 
 /*
  * Architecture-specific system calls
diff --git a/include/uapi/linux/lsm.h b/include/uapi/linux/lsm.h
index f27c9a9cc376..eeda59a77c02 100644
--- a/include/uapi/linux/lsm.h
+++ b/include/uapi/linux/lsm.h
@@ -9,6 +9,36 @@
 #ifndef _UAPI_LINUX_LSM_H
 #define _UAPI_LINUX_LSM_H
 
+#include <linux/types.h>
+#include <linux/unistd.h>
+
+/**
+ * struct lsm_ctx - LSM context information
+ * @id: the LSM id number, see LSM_ID_XXX
+ * @flags: LSM specific flags
+ * @len: length of the lsm_ctx struct, @ctx and any other data or padding
+ * @ctx_len: the size of @ctx
+ * @ctx: the LSM context value
+ *
+ * The @len field MUST be equal to the size of the lsm_ctx struct
+ * plus any additional padding and/or data placed after @ctx.
+ *
+ * In all cases @ctx_len MUST be equal to the length of @ctx.
+ * If @ctx is a string value it should be nul terminated with
+ * @ctx_len equal to `strlen(@ctx) + 1`.  Binary values are
+ * supported.
+ *
+ * The @flags and @ctx fields SHOULD only be interpreted by the
+ * LSM specified by @id; they MUST be set to zero/0 when not used.
+ */
+struct lsm_ctx {
+	__u64 id;
+	__u64 flags;
+	__u64 len;
+	__u64 ctx_len;
+	__u8 ctx[];
+};
+
 /*
  * ID tokens to identify Linux Security Modules (LSMs)
  *
@@ -51,4 +81,10 @@
 #define LSM_ATTR_PREV		104
 #define LSM_ATTR_SOCKCREATE	105
 
+/*
+ * LSM_FLAG_XXX definitions identify special handling instructions
+ * for the API.
+ */
+#define LSM_FLAG_SINGLE	0x0001
+
 #endif /* _UAPI_LINUX_LSM_H */
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index 860b2dcf3ac4..d03c78ef1562 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -262,6 +262,10 @@ COND_SYSCALL_COMPAT(recvmsg);
 /* mm/nommu.c, also with MMU */
 COND_SYSCALL(mremap);
 
+/* security/lsm_syscalls.c */
+COND_SYSCALL(lsm_get_self_attr);
+COND_SYSCALL(lsm_set_self_attr);
+
 /* security/keys/keyctl.c */
 COND_SYSCALL(add_key);
 COND_SYSCALL(request_key);
diff --git a/security/Makefile b/security/Makefile
index 18121f8f85cd..59f238490665 100644
--- a/security/Makefile
+++ b/security/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_KEYS)			+= keys/
 
 # always enable default capabilities
 obj-y					+= commoncap.o
+obj-$(CONFIG_SECURITY) 			+= lsm_syscalls.o
 obj-$(CONFIG_MMU)			+= min_addr.o
 
 # Object file lists
diff --git a/security/lsm_syscalls.c b/security/lsm_syscalls.c
new file mode 100644
index 000000000000..ee3881159241
--- /dev/null
+++ b/security/lsm_syscalls.c
@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * System calls implementing the Linux Security Module API.
+ *
+ *  Copyright (C) 2022 Casey Schaufler <casey@schaufler-ca.com>
+ *  Copyright (C) 2022 Intel Corporation
+ */
+
+#include <asm/current.h>
+#include <linux/compiler_types.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/security.h>
+#include <linux/stddef.h>
+#include <linux/syscalls.h>
+#include <linux/types.h>
+#include <linux/lsm_hooks.h>
+#include <uapi/linux/lsm.h>
+
+/**
+ * sys_lsm_set_self_attr - Set current task's security module attribute
+ * @attr: which attribute to set
+ * @ctx: the LSM contexts
+ * @size: size of @ctx
+ * @flags: reserved for future use
+ *
+ * Sets the calling task's LSM context. On success this function
+ * returns 0. If the attribute specified cannot be set a negative
+ * value indicating the reason for the error is returned.
+ */
+SYSCALL_DEFINE4(lsm_set_self_attr, unsigned int, attr, struct lsm_ctx __user *,
+		ctx, size_t, size, u32, flags)
+{
+	return security_setselfattr(attr, ctx, size, flags);
+}
+
+/**
+ * sys_lsm_get_self_attr - Return current task's security module attributes
+ * @attr: which attribute to set
+ * @ctx: the LSM contexts
+ * @size: size of @ctx, updated on return
+ * @flags: reserved for future use
+ *
+ * Returns the calling task's LSM contexts. On success this
+ * function returns the number of @ctx array elements. This value
+ * may be zero if there are no LSM contexts assigned. If @size is
+ * insufficient to contain the return data -E2BIG is returned and
+ * @size is set to the minimum required size. In all other cases
+ * a negative value indicating the error is returned.
+ */
+SYSCALL_DEFINE4(lsm_get_self_attr, unsigned int, attr, struct lsm_ctx __user *,
+		ctx, size_t __user *, size, u32, flags)
+{
+	return security_getselfattr(attr, ctx, size, flags);
+}
diff --git a/security/security.c b/security/security.c
index 501c0884ec03..ca196b585996 100644
--- a/security/security.c
+++ b/security/security.c
@@ -3797,6 +3797,118 @@ void security_d_instantiate(struct dentry *dentry, struct inode *inode)
 }
 EXPORT_SYMBOL(security_d_instantiate);
 
+/**
+ * security_getselfattr - Read an LSM attribute of the current process.
+ * @attr: which attribute to return
+ * @ctx: the user-space destination for the information, or NULL
+ * @size: pointer to the size of space available to receive the data
+ * @flags: special handling options. LSM_FLAG_SINGLE indicates that only
+ * attributes associated with the LSM identified in the passed @ctx be
+ * reported
+ *
+ * Returns the number of attributes found on success, negative value
+ * on error. @size is reset to the total size of the data.
+ * If @size is insufficient to contain the data -E2BIG is returned.
+ */
+int security_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
+			 size_t __user *size, u32 flags)
+{
+	struct security_hook_list *hp;
+	struct lsm_ctx lctx = { .id = LSM_ID_UNDEF, };
+	u8 __user *base = (u8 __user *)ctx;
+	size_t total = 0;
+	size_t entrysize;
+	size_t left;
+	bool toobig = false;
+	int count = 0;
+	int rc;
+
+	if (attr == LSM_ATTR_UNDEF)
+		return -EINVAL;
+	if (size == NULL)
+		return -EINVAL;
+	if (get_user(left, size))
+		return -EFAULT;
+
+	if ((flags & LSM_FLAG_SINGLE) == LSM_FLAG_SINGLE) {
+		if (!ctx)
+			return -EINVAL;
+		if (copy_struct_from_user(&lctx, sizeof(lctx), ctx, left))
+			return -EFAULT;
+		if (lctx.id == LSM_ID_UNDEF)
+			return -EINVAL;
+	} else if (flags) {
+		return -EINVAL;
+	}
+
+	hlist_for_each_entry(hp, &security_hook_heads.getselfattr, list) {
+		if (lctx.id != LSM_ID_UNDEF && lctx.id != hp->lsmid->id)
+			continue;
+		entrysize = left;
+		if (base)
+			ctx = (struct lsm_ctx __user *)(base + total);
+		rc = hp->hook.getselfattr(attr, ctx, &entrysize, flags);
+		if (rc == -EOPNOTSUPP) {
+			rc = 0;
+			continue;
+		}
+		if (rc == -E2BIG) {
+			toobig = true;
+			left = 0;
+			continue;
+		}
+		if (rc < 0)
+			return rc;
+
+		left -= entrysize;
+		total += entrysize;
+		count += rc;
+	}
+	if (put_user(total, size))
+		return -EFAULT;
+	if (toobig)
+		return -E2BIG;
+	if (count == 0)
+		return LSM_RET_DEFAULT(getselfattr);
+	return count;
+}
+
+/**
+ * security_setselfattr - Set an LSM attribute on the current process.
+ * @attr: which attribute to set
+ * @ctx: the user-space source for the information
+ * @size: the size of the data
+ * @flags: reserved for future use, must be 0
+ *
+ * Set an LSM attribute for the current process. The LSM, attribute
+ * and new value are included in @ctx.
+ *
+ * Returns 0 on success, -EINVAL if the input is inconsistent, -EFAULT
+ * if the user buffer is inaccessible or an LSM specific failure.
+ */
+int security_setselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
+			 size_t size, u32 flags)
+{
+	struct security_hook_list *hp;
+	struct lsm_ctx lctx;
+
+	if (flags)
+		return -EINVAL;
+	if (size < sizeof(*ctx))
+		return -EINVAL;
+	if (copy_from_user(&lctx, ctx, sizeof(*ctx)))
+		return -EFAULT;
+	if (size < lctx.len || size < lctx.ctx_len + sizeof(ctx) ||
+	    lctx.len < lctx.ctx_len + sizeof(ctx))
+		return -EINVAL;
+
+	hlist_for_each_entry(hp, &security_hook_heads.setselfattr, list)
+		if ((hp->lsmid->id) == lctx.id)
+			return hp->hook.setselfattr(attr, ctx, size, flags);
+
+	return LSM_RET_DEFAULT(setselfattr);
+}
+
 /**
  * security_getprocattr() - Read an attribute for a task
  * @p: the task
-- 
2.40.1

[PATCH v11 05/11] LSM: Create lsm_list_modules system call

[Casey Schaufler]

Create a system call to report the list of Linux Security Modules
that are active on the system. The list is provided as an array
of LSM ID numbers.

The calling application can use this list determine what LSM
specific actions it might take. That might include choosing an
output format, determining required privilege or bypassing
security module specific behavior.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
---
 Documentation/userspace-api/lsm.rst |  3 +++
 include/linux/syscalls.h            |  1 +
 kernel/sys_ni.c                     |  1 +
 security/lsm_syscalls.c             | 39 +++++++++++++++++++++++++++++
 4 files changed, 44 insertions(+)

diff --git a/Documentation/userspace-api/lsm.rst b/Documentation/userspace-api/lsm.rst
index e6c3f262addc..9edae18a2688 100644
--- a/Documentation/userspace-api/lsm.rst
+++ b/Documentation/userspace-api/lsm.rst
@@ -63,6 +63,9 @@ Get the specified security attributes of the current process
 .. kernel-doc:: security/lsm_syscalls.c
     :identifiers: sys_lsm_get_self_attr
 
+.. kernel-doc:: security/lsm_syscalls.c
+    :identifiers: sys_lsm_list_modules
+
 Additional documentation
 ========================
 
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 9a94c31bf6b6..ddbcc333f3c3 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -1063,6 +1063,7 @@ asmlinkage long sys_lsm_get_self_attr(unsigned int attr, struct lsm_ctx *ctx,
 				      size_t *size, __u32 flags);
 asmlinkage long sys_lsm_set_self_attr(unsigned int attr, struct lsm_ctx *ctx,
 				      size_t size, __u32 flags);
+asmlinkage long sys_lsm_list_modules(u64 *ids, size_t *size, u32 flags);
 
 /*
  * Architecture-specific system calls
diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c
index d03c78ef1562..ceb3d21a62d0 100644
--- a/kernel/sys_ni.c
+++ b/kernel/sys_ni.c
@@ -265,6 +265,7 @@ COND_SYSCALL(mremap);
 /* security/lsm_syscalls.c */
 COND_SYSCALL(lsm_get_self_attr);
 COND_SYSCALL(lsm_set_self_attr);
+COND_SYSCALL(lsm_list_modules);
 
 /* security/keys/keyctl.c */
 COND_SYSCALL(add_key);
diff --git a/security/lsm_syscalls.c b/security/lsm_syscalls.c
index ee3881159241..f03f2d17ab49 100644
--- a/security/lsm_syscalls.c
+++ b/security/lsm_syscalls.c
@@ -53,3 +53,42 @@ SYSCALL_DEFINE4(lsm_get_self_attr, unsigned int, attr, struct lsm_ctx __user *,
 {
 	return security_getselfattr(attr, ctx, size, flags);
 }
+
+/**
+ * sys_lsm_list_modules - Return a list of the active security modules
+ * @ids: the LSM module ids
+ * @size: pointer to size of @ids, updated on return
+ * @flags: reserved for future use, must be zero
+ *
+ * Returns a list of the active LSM ids. On success this function
+ * returns the number of @ids array elements. This value may be zero
+ * if there are no LSMs active. If @size is insufficient to contain
+ * the return data -E2BIG is returned and @size is set to the minimum
+ * required size. In all other cases a negative value indicating the
+ * error is returned.
+ */
+SYSCALL_DEFINE3(lsm_list_modules, u64 __user *, ids, size_t __user *, size,
+		u32, flags)
+{
+	size_t total_size = lsm_active_cnt * sizeof(*ids);
+	size_t usize;
+	int i;
+
+	if (flags)
+		return -EINVAL;
+
+	if (get_user(usize, size))
+		return -EFAULT;
+
+	if (put_user(total_size, size) != 0)
+		return -EFAULT;
+
+	if (usize < total_size)
+		return -E2BIG;
+
+	for (i = 0; i < lsm_active_cnt; i++)
+		if (put_user(lsm_idlist[i]->id, ids++))
+			return -EFAULT;
+
+	return lsm_active_cnt;
+}
-- 
2.40.1

[PATCH v11 06/11] LSM: wireup Linux Security Module syscalls

[Casey Schaufler]

Wireup lsm_get_self_attr, lsm_set_self_attr and lsm_list_modules
system calls.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: linux-api@vger.kernel.org
---
 arch/alpha/kernel/syscalls/syscall.tbl              |  3 +++
 arch/arm/tools/syscall.tbl                          |  3 +++
 arch/arm64/include/asm/unistd.h                     |  2 +-
 arch/arm64/include/asm/unistd32.h                   |  6 ++++++
 arch/ia64/kernel/syscalls/syscall.tbl               |  3 +++
 arch/m68k/kernel/syscalls/syscall.tbl               |  3 +++
 arch/microblaze/kernel/syscalls/syscall.tbl         |  3 +++
 arch/mips/kernel/syscalls/syscall_n32.tbl           |  3 +++
 arch/mips/kernel/syscalls/syscall_n64.tbl           |  3 +++
 arch/mips/kernel/syscalls/syscall_o32.tbl           |  3 +++
 arch/parisc/kernel/syscalls/syscall.tbl             |  3 +++
 arch/powerpc/kernel/syscalls/syscall.tbl            |  3 +++
 arch/s390/kernel/syscalls/syscall.tbl               |  3 +++
 arch/sh/kernel/syscalls/syscall.tbl                 |  3 +++
 arch/sparc/kernel/syscalls/syscall.tbl              |  3 +++
 arch/x86/entry/syscalls/syscall_32.tbl              |  3 +++
 arch/x86/entry/syscalls/syscall_64.tbl              |  3 +++
 arch/xtensa/kernel/syscalls/syscall.tbl             |  3 +++
 include/uapi/asm-generic/unistd.h                   | 11 ++++++++++-
 tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl |  3 +++
 tools/perf/arch/powerpc/entry/syscalls/syscall.tbl  |  3 +++
 tools/perf/arch/s390/entry/syscalls/syscall.tbl     |  3 +++
 tools/perf/arch/x86/entry/syscalls/syscall_64.tbl   |  3 +++
 23 files changed, 77 insertions(+), 2 deletions(-)

diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl
index 8ebacf37a8cf..178e2792c251 100644
--- a/arch/alpha/kernel/syscalls/syscall.tbl
+++ b/arch/alpha/kernel/syscalls/syscall.tbl
@@ -490,3 +490,6 @@
 558	common	process_mrelease		sys_process_mrelease
 559	common  futex_waitv                     sys_futex_waitv
 560	common	set_mempolicy_home_node		sys_ni_syscall
+561	common	lsm_get_self_attr		sys_lsm_get_self_attr
+562	common	lsm_list_modules		sys_lsm_list_modules
+563	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl
index ac964612d8b0..9cda144f9631 100644
--- a/arch/arm/tools/syscall.tbl
+++ b/arch/arm/tools/syscall.tbl
@@ -464,3 +464,6 @@
 448	common	process_mrelease		sys_process_mrelease
 449	common	futex_waitv			sys_futex_waitv
 450	common	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr		sys_lsm_get_self_attr
+452	common	lsm_list_modules		sys_lsm_list_modules
+453	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h
index 037feba03a51..6a28fb91b85d 100644
--- a/arch/arm64/include/asm/unistd.h
+++ b/arch/arm64/include/asm/unistd.h
@@ -39,7 +39,7 @@
 #define __ARM_NR_compat_set_tls		(__ARM_NR_COMPAT_BASE + 5)
 #define __ARM_NR_COMPAT_END		(__ARM_NR_COMPAT_BASE + 0x800)
 
-#define __NR_compat_syscalls		451
+#define __NR_compat_syscalls		454
 #endif
 
 #define __ARCH_WANT_SYS_CLONE
diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h
index 604a2053d006..72022ffd5faa 100644
--- a/arch/arm64/include/asm/unistd32.h
+++ b/arch/arm64/include/asm/unistd32.h
@@ -907,6 +907,12 @@ __SYSCALL(__NR_process_mrelease, sys_process_mrelease)
 __SYSCALL(__NR_futex_waitv, sys_futex_waitv)
 #define __NR_set_mempolicy_home_node 450
 __SYSCALL(__NR_set_mempolicy_home_node, sys_set_mempolicy_home_node)
+#define __NR_lsm_get_self_attr 451
+__SYSCALL(__NR_lsm_get_self_attr, sys_lsm_get_self_attr)
+#define __NR_lsm_list_modules 452
+__SYSCALL(__NR_lsm_list_modules, sys_lsm_list_modules)
+#define __NR_lsm_set_self_attr 453
+__SYSCALL(__NR_lsm_set_self_attr, sys_lsm_set_self_attr)
 
 /*
  * Please add new compat syscalls above this comment and update
diff --git a/arch/ia64/kernel/syscalls/syscall.tbl b/arch/ia64/kernel/syscalls/syscall.tbl
index 72c929d9902b..c52e9d87f47d 100644
--- a/arch/ia64/kernel/syscalls/syscall.tbl
+++ b/arch/ia64/kernel/syscalls/syscall.tbl
@@ -371,3 +371,6 @@
 448	common	process_mrelease		sys_process_mrelease
 449	common  futex_waitv                     sys_futex_waitv
 450	common	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr		sys_lsm_get_self_attr
+452	common	lsm_list_modules		sys_lsm_list_modules
+453	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl
index b1f3940bc298..31eac3c99d84 100644
--- a/arch/m68k/kernel/syscalls/syscall.tbl
+++ b/arch/m68k/kernel/syscalls/syscall.tbl
@@ -450,3 +450,6 @@
 448	common	process_mrelease		sys_process_mrelease
 449	common  futex_waitv                     sys_futex_waitv
 450	common	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr		sys_lsm_get_self_attr
+452	common	lsm_list_modules		sys_lsm_list_modules
+453	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl
index 820145e47350..5037fa1f74b8 100644
--- a/arch/microblaze/kernel/syscalls/syscall.tbl
+++ b/arch/microblaze/kernel/syscalls/syscall.tbl
@@ -456,3 +456,6 @@
 448	common	process_mrelease		sys_process_mrelease
 449	common  futex_waitv                     sys_futex_waitv
 450	common	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr		sys_lsm_get_self_attr
+452	common	lsm_list_modules		sys_lsm_list_modules
+453	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl
index 253ff994ed2e..29545b3ec587 100644
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n32.tbl
@@ -389,3 +389,6 @@
 448	n32	process_mrelease		sys_process_mrelease
 449	n32	futex_waitv			sys_futex_waitv
 450	n32	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	n32	lsm_get_self_attr		sys_lsm_get_self_attr
+452	n32	lsm_list_modules		sys_lsm_list_modules
+453	n32	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl
index 3f1886ad9d80..8492aa4a771f 100644
--- a/arch/mips/kernel/syscalls/syscall_n64.tbl
+++ b/arch/mips/kernel/syscalls/syscall_n64.tbl
@@ -365,3 +365,6 @@
 448	n64	process_mrelease		sys_process_mrelease
 449	n64	futex_waitv			sys_futex_waitv
 450	common	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	n64	lsm_get_self_attr		sys_lsm_get_self_attr
+452	n64	lsm_list_modules		sys_lsm_list_modules
+453	n64	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl
index 8f243e35a7b2..d74fd86de2a2 100644
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl
+++ b/arch/mips/kernel/syscalls/syscall_o32.tbl
@@ -438,3 +438,6 @@
 448	o32	process_mrelease		sys_process_mrelease
 449	o32	futex_waitv			sys_futex_waitv
 450	o32	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	o32	lsm_get_self_attr		sys_lsm_get_self_attr
+452	o32	lsm_list_modules		sys_lsm_list_modules
+453	032	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl
index 0e42fceb2d5e..d1a5f3120d6c 100644
--- a/arch/parisc/kernel/syscalls/syscall.tbl
+++ b/arch/parisc/kernel/syscalls/syscall.tbl
@@ -448,3 +448,6 @@
 448	common	process_mrelease		sys_process_mrelease
 449	common	futex_waitv			sys_futex_waitv
 450	common	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr		sys_lsm_get_self_attr
+452	common	lsm_list_modules		sys_lsm_list_modules
+453	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl
index a0be127475b1..a414fe8c069b 100644
--- a/arch/powerpc/kernel/syscalls/syscall.tbl
+++ b/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -537,3 +537,6 @@
 448	common	process_mrelease		sys_process_mrelease
 449	common  futex_waitv                     sys_futex_waitv
 450 	nospu	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr		sys_lsm_get_self_attr
+452	common	lsm_list_modules		sys_lsm_list_modules
+453	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl
index b68f47541169..7511e05b785d 100644
--- a/arch/s390/kernel/syscalls/syscall.tbl
+++ b/arch/s390/kernel/syscalls/syscall.tbl
@@ -453,3 +453,6 @@
 448  common	process_mrelease	sys_process_mrelease		sys_process_mrelease
 449  common	futex_waitv		sys_futex_waitv			sys_futex_waitv
 450  common	set_mempolicy_home_node	sys_set_mempolicy_home_node	sys_set_mempolicy_home_node
+451  common	lsm_get_self_attr	sys_lsm_get_self_attr		sys_lsm_get_self_attr
+452  common	lsm_list_modules	sys_lsm_list_modules		sys_lsm_list_modules
+453  common	lsm_set_self_attr	sys_lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl
index 2de85c977f54..1a75a599bb55 100644
--- a/arch/sh/kernel/syscalls/syscall.tbl
+++ b/arch/sh/kernel/syscalls/syscall.tbl
@@ -453,3 +453,6 @@
 448	common	process_mrelease		sys_process_mrelease
 449	common  futex_waitv                     sys_futex_waitv
 450	common	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr		sys_lsm_get_self_attr
+452	common	lsm_list_modules		sys_lsm_list_modules
+453	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl
index 4398cc6fb68d..80b165091f6f 100644
--- a/arch/sparc/kernel/syscalls/syscall.tbl
+++ b/arch/sparc/kernel/syscalls/syscall.tbl
@@ -496,3 +496,6 @@
 448	common	process_mrelease		sys_process_mrelease
 449	common  futex_waitv                     sys_futex_waitv
 450	common	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr		sys_lsm_get_self_attr
+452	common	lsm_list_modules		sys_lsm_list_modules
+453	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl
index 320480a8db4f..130f9feb9eb9 100644
--- a/arch/x86/entry/syscalls/syscall_32.tbl
+++ b/arch/x86/entry/syscalls/syscall_32.tbl
@@ -455,3 +455,6 @@
 448	i386	process_mrelease	sys_process_mrelease
 449	i386	futex_waitv		sys_futex_waitv
 450	i386	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	i386	lsm_get_self_attr	sys_lsm_get_self_attr
+452	i386	lsm_list_modules	sys_lsm_list_modules
+453	i386	lsm_set_self_attr	sys_lsm_set_self_attr
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl
index c84d12608cd2..96dd45bc5988 100644
--- a/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/arch/x86/entry/syscalls/syscall_64.tbl
@@ -372,6 +372,9 @@
 448	common	process_mrelease	sys_process_mrelease
 449	common	futex_waitv		sys_futex_waitv
 450	common	set_mempolicy_home_node	sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr	sys_lsm_get_self_attr
+452	common	lsm_list_modules	sys_lsm_list_modules
+453	common	lsm_set_self_attr	sys_lsm_set_self_attr
 
 #
 # Due to a historical design error, certain syscalls are numbered differently
diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl
index 52c94ab5c205..2610aba19802 100644
--- a/arch/xtensa/kernel/syscalls/syscall.tbl
+++ b/arch/xtensa/kernel/syscalls/syscall.tbl
@@ -421,3 +421,6 @@
 448	common	process_mrelease		sys_process_mrelease
 449	common  futex_waitv                     sys_futex_waitv
 450	common	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr		sys_lsm_get_self_attr
+452	common	lsm_list_modules		sys_lsm_list_modules
+453	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 45fa180cc56a..93f89fb06ef5 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -886,8 +886,17 @@ __SYSCALL(__NR_futex_waitv, sys_futex_waitv)
 #define __NR_set_mempolicy_home_node 450
 __SYSCALL(__NR_set_mempolicy_home_node, sys_set_mempolicy_home_node)
 
+#define __NR_lsm_get_self_attr 451
+__SYSCALL(__NR_lsm_get_self_attr, sys_lsm_get_self_attr)
+
+#define __NR_lsm_list_modules 452
+__SYSCALL(__NR_lsm_list_modules, sys_lsm_list_modules)
+
+#define __NR_lsm_set_self_attr 453
+__SYSCALL(__NR_lsm_set_self_attr, sys_lsm_set_self_attr)
+
 #undef __NR_syscalls
-#define __NR_syscalls 451
+#define __NR_syscalls 454
 
 /*
  * 32 bit systems traditionally used different
diff --git a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
index 3f1886ad9d80..8492aa4a771f 100644
--- a/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
+++ b/tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl
@@ -365,3 +365,6 @@
 448	n64	process_mrelease		sys_process_mrelease
 449	n64	futex_waitv			sys_futex_waitv
 450	common	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	n64	lsm_get_self_attr		sys_lsm_get_self_attr
+452	n64	lsm_list_modules		sys_lsm_list_modules
+453	n64	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
index a0be127475b1..a414fe8c069b 100644
--- a/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/powerpc/entry/syscalls/syscall.tbl
@@ -537,3 +537,6 @@
 448	common	process_mrelease		sys_process_mrelease
 449	common  futex_waitv                     sys_futex_waitv
 450 	nospu	set_mempolicy_home_node		sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr		sys_lsm_get_self_attr
+452	common	lsm_list_modules		sys_lsm_list_modules
+453	common	lsm_set_self_attr		sys_lsm_set_self_attr
diff --git a/tools/perf/arch/s390/entry/syscalls/syscall.tbl b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
index 799147658dee..f9257e040109 100644
--- a/tools/perf/arch/s390/entry/syscalls/syscall.tbl
+++ b/tools/perf/arch/s390/entry/syscalls/syscall.tbl
@@ -453,3 +453,6 @@
 448  common	process_mrelease	sys_process_mrelease		sys_process_mrelease
 449  common	futex_waitv		sys_futex_waitv			sys_futex_waitv
 450  common	set_mempolicy_home_node	sys_set_mempolicy_home_node	sys_set_mempolicy_home_node
+451  common	lsm_get_self_attr	sys_lsm_get_self_attr	sys_lsm_get_self_attr
+452  common	lsm_list_modules	sys_lsm_list_modules	sys_lsm_list_modules
+453  common	lsm_set_self_attr	sys_lsm_set_self_attr	sys_lsm_set_self_attr
diff --git a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
index c84d12608cd2..96dd45bc5988 100644
--- a/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
+++ b/tools/perf/arch/x86/entry/syscalls/syscall_64.tbl
@@ -372,6 +372,9 @@
 448	common	process_mrelease	sys_process_mrelease
 449	common	futex_waitv		sys_futex_waitv
 450	common	set_mempolicy_home_node	sys_set_mempolicy_home_node
+451	common	lsm_get_self_attr	sys_lsm_get_self_attr
+452	common	lsm_list_modules	sys_lsm_list_modules
+453	common	lsm_set_self_attr	sys_lsm_set_self_attr
 
 #
 # Due to a historical design error, certain syscalls are numbered differently
-- 
2.40.1

[PATCH v11 07/11] LSM: Helpers for attribute names and filling lsm_ctx

[Casey Schaufler]

Add lsm_name_to_attr(), which translates a text string to a
LSM_ATTR value if one is available.

Add lsm_fill_user_ctx(), which fills a struct lsm_ctx, including
the trailing attribute value.

All are used in module specific components of LSM system calls.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
---
 include/linux/security.h | 14 +++++++++++++
 security/lsm_syscalls.c  | 24 ++++++++++++++++++++++
 security/security.c      | 44 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 82 insertions(+)

diff --git a/include/linux/security.h b/include/linux/security.h
index 475d0abfebda..75ac91223c2d 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -32,6 +32,7 @@
 #include <linux/string.h>
 #include <linux/mm.h>
 #include <linux/sockptr.h>
+#include <uapi/linux/lsm.h>
 
 struct linux_binprm;
 struct cred;
@@ -263,6 +264,7 @@ int unregister_blocking_lsm_notifier(struct notifier_block *nb);
 /* prototypes */
 extern int security_init(void);
 extern int early_security_init(void);
+extern u64 lsm_name_to_attr(const char *name);
 
 /* Security operations */
 int security_binder_set_context_mgr(const struct cred *mgr);
@@ -488,6 +490,8 @@ 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_locked_down(enum lockdown_reason what);
+int lsm_fill_user_ctx(struct lsm_ctx __user *ctx, void *context,
+		      size_t context_size, u64 id, u64 flags);
 #else /* CONFIG_SECURITY */
 
 static inline int call_blocking_lsm_notifier(enum lsm_event event, void *data)
@@ -505,6 +509,11 @@ static inline  int unregister_blocking_lsm_notifier(struct notifier_block *nb)
 	return 0;
 }
 
+static inline u64 lsm_name_to_attr(const char *name)
+{
+	return LSM_ATTR_UNDEF;
+}
+
 static inline void security_free_mnt_opts(void **mnt_opts)
 {
 }
@@ -1408,6 +1417,11 @@ static inline int security_locked_down(enum lockdown_reason what)
 {
 	return 0;
 }
+static inline int lsm_fill_user_ctx(struct lsm_ctx __user *ctx, void *context,
+				    size_t context_size, u64 id, u64 flags)
+{
+	return -EOPNOTSUPP;
+}
 #endif	/* CONFIG_SECURITY */
 
 #if defined(CONFIG_SECURITY) && defined(CONFIG_WATCH_QUEUE)
diff --git a/security/lsm_syscalls.c b/security/lsm_syscalls.c
index f03f2d17ab49..bc22f05e2d8c 100644
--- a/security/lsm_syscalls.c
+++ b/security/lsm_syscalls.c
@@ -17,6 +17,30 @@
 #include <linux/lsm_hooks.h>
 #include <uapi/linux/lsm.h>
 
+/**
+ * lsm_name_to_attr - map an LSM attribute name to its ID
+ * @name: name of the attribute
+ *
+ * Returns the LSM attribute value associated with @name, or 0 if
+ * there is no mapping.
+ */
+u64 lsm_name_to_attr(const char *name)
+{
+	if (!strcmp(name, "current"))
+		return LSM_ATTR_CURRENT;
+	if (!strcmp(name, "exec"))
+		return LSM_ATTR_EXEC;
+	if (!strcmp(name, "fscreate"))
+		return LSM_ATTR_FSCREATE;
+	if (!strcmp(name, "keycreate"))
+		return LSM_ATTR_KEYCREATE;
+	if (!strcmp(name, "prev"))
+		return LSM_ATTR_PREV;
+	if (!strcmp(name, "sockcreate"))
+		return LSM_ATTR_SOCKCREATE;
+	return LSM_ATTR_UNDEF;
+}
+
 /**
  * sys_lsm_set_self_attr - Set current task's security module attribute
  * @attr: which attribute to set
diff --git a/security/security.c b/security/security.c
index ca196b585996..3d8c3c3a6d92 100644
--- a/security/security.c
+++ b/security/security.c
@@ -769,6 +769,50 @@ static int lsm_superblock_alloc(struct super_block *sb)
 	return 0;
 }
 
+/**
+ * lsm_fill_user_ctx - Fill a user space lsm_ctx structure
+ * @ctx: an LSM context to be filled
+ * @context: the new context value
+ * @context_size: the size of the new context value
+ * @id: LSM id
+ * @flags: LSM defined flags
+ *
+ * Fill all of the fields in a user space lsm_ctx structure.
+ * Caller is assumed to have verified that @ctx has enough space
+ * for @context.
+ *
+ * The total length is padded to a multiple of 64 bits to
+ * accomodate possible alignment issues.
+ *
+ * Returns 0 on success, -EFAULT on a copyout error, -ENOMEM
+ * if memory can't be allocated.
+ */
+int lsm_fill_user_ctx(struct lsm_ctx __user *ctx, void *context,
+		      size_t context_size, u64 id, u64 flags)
+{
+	struct lsm_ctx *lctx;
+	size_t locallen = struct_size(lctx, ctx, context_size);
+	int rc = 0;
+
+	lctx = kzalloc(locallen, GFP_KERNEL);
+	if (lctx == NULL)
+		return -ENOMEM;
+
+	lctx->id = id;
+	lctx->flags = flags;
+	lctx->ctx_len = context_size;
+	lctx->len = locallen;
+
+	memcpy(lctx->ctx, context, context_size);
+
+	if (copy_to_user(ctx, lctx, locallen))
+		rc = -EFAULT;
+
+	kfree(lctx);
+
+	return rc;
+}
+
 /*
  * The default value of the LSM hook is defined in linux/lsm_hook_defs.h and
  * can be accessed with:
-- 
2.40.1

[PATCH v11 08/11] Smack: implement setselfattr and getselfattr hooks

[Casey Schaufler]

Implement Smack support for security_[gs]etselfattr.
Refactor the setprocattr hook to avoid code duplication.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 security/smack/smack_lsm.c | 106 +++++++++++++++++++++++++++++++++++--
 1 file changed, 101 insertions(+), 5 deletions(-)

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index cf847cfe5ed8..4a84639e9db9 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -3536,6 +3536,45 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
 	return;
 }
 
+/**
+ * smack_getselfattr - Smack current process attribute
+ * @attr: which attribute to fetch
+ * @ctx: buffer to receive the result
+ * @size: available size in, actual size out
+ * @flags: unused
+ *
+ * Fill the passed user space @ctx with the details of the requested
+ * attribute.
+ *
+ * Returns 1, the number of attributes, on success, an error code otherwise.
+ */
+static int smack_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
+			     size_t *size, u32 flags)
+{
+	struct smack_known *skp = smk_of_current();
+	int total;
+	int slen;
+	int rc;
+
+	if (attr != LSM_ATTR_CURRENT)
+		return -EOPNOTSUPP;
+
+	slen = strlen(skp->smk_known) + 1;
+	total = ALIGN(slen + sizeof(*ctx), 8);
+	if (total > *size)
+		rc = -E2BIG;
+	else if (ctx)
+		rc = lsm_fill_user_ctx(ctx, skp->smk_known, slen, LSM_ID_SMACK,
+				       0);
+	else
+		rc = 1;
+
+	*size = total;
+	if (rc >= 0)
+		return 1;
+	return rc;
+}
+
 /**
  * smack_getprocattr - Smack process attribute access
  * @p: the object task
@@ -3565,8 +3604,8 @@ static int smack_getprocattr(struct task_struct *p, const char *name, char **val
 }
 
 /**
- * smack_setprocattr - Smack process attribute setting
- * @name: the name of the attribute in /proc/.../attr
+ * do_setattr - Smack process attribute setting
+ * @attr: the ID of the attribute
  * @value: the value to set
  * @size: the size of the value
  *
@@ -3575,7 +3614,7 @@ static int smack_getprocattr(struct task_struct *p, const char *name, char **val
  *
  * Returns the length of the smack label or an error code
  */
-static int smack_setprocattr(const char *name, void *value, size_t size)
+static int do_setattr(u64 attr, void *value, size_t size)
 {
 	struct task_smack *tsp = smack_cred(current_cred());
 	struct cred *new;
@@ -3589,8 +3628,8 @@ static int smack_setprocattr(const char *name, void *value, size_t size)
 	if (value == NULL || size == 0 || size >= SMK_LONGLABEL)
 		return -EINVAL;
 
-	if (strcmp(name, "current") != 0)
-		return -EINVAL;
+	if (attr != LSM_ATTR_CURRENT)
+		return -EOPNOTSUPP;
 
 	skp = smk_import_entry(value, size);
 	if (IS_ERR(skp))
@@ -3629,6 +3668,61 @@ static int smack_setprocattr(const char *name, void *value, size_t size)
 	return size;
 }
 
+/**
+ * smack_setselfattr - Set a Smack process attribute
+ * @attr: which attribute to set
+ * @ctx: buffer containing the data
+ * @size: size of @ctx
+ * @flags: unused
+ *
+ * Fill the passed user space @ctx with the details of the requested
+ * attribute.
+ *
+ * Returns 0 on success, an error code otherwise.
+ */
+static int smack_setselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
+			     size_t size, u32 flags)
+{
+	struct lsm_ctx *lctx;
+	int rc;
+
+	lctx = kmalloc(size, GFP_KERNEL);
+	if (lctx == NULL)
+		return -ENOMEM;
+
+	if (copy_from_user(lctx, ctx, size))
+		rc = -EFAULT;
+	else if (lctx->ctx_len > size)
+		rc = -E2BIG;
+	else
+		rc = do_setattr(attr, lctx->ctx, lctx->ctx_len);
+
+	kfree(lctx);
+	if (rc > 0)
+		return 0;
+	return rc;
+}
+
+/**
+ * smack_setprocattr - Smack process attribute setting
+ * @name: the name of the attribute in /proc/.../attr
+ * @value: the value to set
+ * @size: the size of the value
+ *
+ * Sets the Smack value of the task. Only setting self
+ * is permitted and only with privilege
+ *
+ * Returns the length of the smack label or an error code
+ */
+static int smack_setprocattr(const char *name, void *value, size_t size)
+{
+	int attr = lsm_name_to_attr(name);
+
+	if (attr == LSM_ATTR_UNDEF)
+		return do_setattr(attr, value, size);
+	return -EINVAL;
+}
+
 /**
  * smack_unix_stream_connect - Smack access on UDS
  * @sock: one sock
@@ -4939,6 +5033,8 @@ static struct security_hook_list smack_hooks[] __ro_after_init = {
 
 	LSM_HOOK_INIT(d_instantiate, smack_d_instantiate),
 
+	LSM_HOOK_INIT(getselfattr, smack_getselfattr),
+	LSM_HOOK_INIT(setselfattr, smack_setselfattr),
 	LSM_HOOK_INIT(getprocattr, smack_getprocattr),
 	LSM_HOOK_INIT(setprocattr, smack_setprocattr),
 
-- 
2.40.1

[PATCH v11 09/11] AppArmor: Add selfattr hooks

[Casey Schaufler]

Add hooks for setselfattr and getselfattr. These hooks are not very
different from their setprocattr and getprocattr equivalents, and
much of the code is shared.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: John Johansen <john.johansen@canonical.com>
---
 security/apparmor/include/procattr.h |   2 +-
 security/apparmor/lsm.c              | 102 +++++++++++++++++++++++++--
 security/apparmor/procattr.c         |  10 +--
 3 files changed, 103 insertions(+), 11 deletions(-)

diff --git a/security/apparmor/include/procattr.h b/security/apparmor/include/procattr.h
index 31689437e0e1..03dbfdb2f2c0 100644
--- a/security/apparmor/include/procattr.h
+++ b/security/apparmor/include/procattr.h
@@ -11,7 +11,7 @@
 #ifndef __AA_PROCATTR_H
 #define __AA_PROCATTR_H
 
-int aa_getprocattr(struct aa_label *label, char **string);
+int aa_getprocattr(struct aa_label *label, char **string, bool newline);
 int aa_setprocattr_changehat(char *args, size_t size, int flags);
 
 #endif /* __AA_PROCATTR_H */
diff --git a/security/apparmor/lsm.c b/security/apparmor/lsm.c
index 308cb3a281c3..7d99d5be4c12 100644
--- a/security/apparmor/lsm.c
+++ b/security/apparmor/lsm.c
@@ -630,6 +630,54 @@ static int apparmor_sb_pivotroot(const struct path *old_path,
 	return error;
 }
 
+static int apparmor_getselfattr(unsigned int attr, struct lsm_ctx __user *lx,
+				size_t *size, u32 flags)
+{
+	int error = -ENOENT;
+	struct aa_task_ctx *ctx = task_ctx(current);
+	struct aa_label *label = NULL;
+	size_t total_len = 0;
+	char *value;
+
+	switch (attr) {
+	case LSM_ATTR_CURRENT:
+		label = aa_get_newest_label(cred_label(current_cred()));
+		break;
+	case LSM_ATTR_PREV:
+		if (ctx->previous)
+			label = aa_get_newest_label(ctx->previous);
+		break;
+	case LSM_ATTR_EXEC:
+		if (ctx->onexec)
+			label = aa_get_newest_label(ctx->onexec);
+		break;
+	default:
+		error = -EOPNOTSUPP;
+		break;
+	}
+
+	if (label) {
+		error = aa_getprocattr(label, &value, false);
+		if (error > 0) {
+			total_len = ALIGN(struct_size(lx, ctx, error), 8);
+			if (total_len > *size)
+				error = -E2BIG;
+			else if (lx)
+				error = lsm_fill_user_ctx(lx, value, error,
+							  LSM_ID_APPARMOR, 0);
+			else
+				error = 1;
+		}
+	}
+
+	aa_put_label(label);
+
+	*size = total_len;
+	if (error < 0)
+		return error;
+	return 1;
+}
+
 static int apparmor_getprocattr(struct task_struct *task, const char *name,
 				char **value)
 {
@@ -649,7 +697,7 @@ static int apparmor_getprocattr(struct task_struct *task, const char *name,
 		error = -EINVAL;
 
 	if (label)
-		error = aa_getprocattr(label, value);
+		error = aa_getprocattr(label, value, true);
 
 	aa_put_label(label);
 	put_cred(cred);
@@ -657,8 +705,7 @@ static int apparmor_getprocattr(struct task_struct *task, const char *name,
 	return error;
 }
 
-static int apparmor_setprocattr(const char *name, void *value,
-				size_t size)
+static int do_setattr(u64 attr, void *value, size_t size)
 {
 	char *command, *largs = NULL, *args = value;
 	size_t arg_size;
@@ -689,7 +736,7 @@ static int apparmor_setprocattr(const char *name, void *value,
 		goto out;
 
 	arg_size = size - (args - (largs ? largs : (char *) value));
-	if (strcmp(name, "current") == 0) {
+	if (attr == LSM_ATTR_CURRENT) {
 		if (strcmp(command, "changehat") == 0) {
 			error = aa_setprocattr_changehat(args, arg_size,
 							 AA_CHANGE_NOFLAGS);
@@ -704,7 +751,7 @@ static int apparmor_setprocattr(const char *name, void *value,
 			error = aa_change_profile(args, AA_CHANGE_STACK);
 		} else
 			goto fail;
-	} else if (strcmp(name, "exec") == 0) {
+	} else if (attr == LSM_ATTR_EXEC) {
 		if (strcmp(command, "exec") == 0)
 			error = aa_change_profile(args, AA_CHANGE_ONEXEC);
 		else if (strcmp(command, "stack") == 0)
@@ -724,13 +771,54 @@ static int apparmor_setprocattr(const char *name, void *value,
 
 fail:
 	aad(&sa)->label = begin_current_label_crit_section();
-	aad(&sa)->info = name;
+	if (attr == LSM_ATTR_CURRENT)
+		aad(&sa)->info = "current";
+	else if (attr == LSM_ATTR_EXEC)
+		aad(&sa)->info = "exec";
+	else
+		aad(&sa)->info = "invalid";
 	aad(&sa)->error = error = -EINVAL;
 	aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
 	end_current_label_crit_section(aad(&sa)->label);
 	goto out;
 }
 
+static int apparmor_setselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
+				size_t size, u32 flags)
+{
+	struct lsm_ctx *lctx;
+	int rc;
+
+	if (attr != LSM_ATTR_CURRENT && attr != LSM_ATTR_EXEC)
+		return -EOPNOTSUPP;
+
+	lctx = kmalloc(size, GFP_KERNEL);
+	if (lctx == NULL)
+		return -ENOMEM;
+
+	if (copy_from_user(lctx, ctx, size))
+		rc = -EFAULT;
+	else if (lctx->ctx_len > size)
+		rc = -EINVAL;
+	else
+		rc = do_setattr(attr, lctx->ctx, lctx->ctx_len);
+
+	kfree(lctx);
+	if (rc > 0)
+		return 0;
+	return rc;
+}
+
+static int apparmor_setprocattr(const char *name, void *value,
+				size_t size)
+{
+	int attr = lsm_name_to_attr(name);
+
+	if (attr)
+		return do_setattr(attr, value, size);
+	return -EINVAL;
+}
+
 /**
  * apparmor_bprm_committing_creds - do task cleanup on committing new creds
  * @bprm: binprm for the exec  (NOT NULL)
@@ -1253,6 +1341,8 @@ static struct security_hook_list apparmor_hooks[] __ro_after_init = {
 	LSM_HOOK_INIT(file_lock, apparmor_file_lock),
 	LSM_HOOK_INIT(file_truncate, apparmor_file_truncate),
 
+	LSM_HOOK_INIT(getselfattr, apparmor_getselfattr),
+	LSM_HOOK_INIT(setselfattr, apparmor_setselfattr),
 	LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
 	LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
 
diff --git a/security/apparmor/procattr.c b/security/apparmor/procattr.c
index 197d41f9c32b..e3857e3d7c6c 100644
--- a/security/apparmor/procattr.c
+++ b/security/apparmor/procattr.c
@@ -20,6 +20,7 @@
  * aa_getprocattr - Return the label information for @label
  * @label: the label to print label info about  (NOT NULL)
  * @string: Returns - string containing the label info (NOT NULL)
+ * @newline: indicates that a newline should be added
  *
  * Requires: label != NULL && string != NULL
  *
@@ -27,7 +28,7 @@
  *
  * Returns: size of string placed in @string else error code on failure
  */
-int aa_getprocattr(struct aa_label *label, char **string)
+int aa_getprocattr(struct aa_label *label, char **string, bool newline)
 {
 	struct aa_ns *ns = labels_ns(label);
 	struct aa_ns *current_ns = aa_get_current_ns();
@@ -57,11 +58,12 @@ int aa_getprocattr(struct aa_label *label, char **string)
 		return len;
 	}
 
-	(*string)[len] = '\n';
-	(*string)[len + 1] = 0;
+	if (newline)
+		(*string)[len++] = '\n';
+	(*string)[len] = 0;
 
 	aa_put_ns(current_ns);
-	return len + 1;
+	return len;
 }
 
 /**
-- 
2.40.1

[PATCH v11 10/11] SELinux: Add selfattr hooks

[Casey Schaufler]

Add hooks for setselfattr and getselfattr. These hooks are not very
different from their setprocattr and getprocattr equivalents, and
much of the code is shared.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Cc: selinux@vger.kernel.org
Cc: Paul Moore <paul@paul-moore.com>
---
 security/selinux/hooks.c | 148 ++++++++++++++++++++++++++++++++-------
 1 file changed, 121 insertions(+), 27 deletions(-)

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 49ec74bc006c..a4a536552717 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -6226,8 +6226,8 @@ static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
 		inode_doinit_with_dentry(inode, dentry);
 }
 
-static int selinux_getprocattr(struct task_struct *p,
-			       const char *name, char **value)
+static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
+			       char **value)
 {
 	const struct task_security_struct *__tsec;
 	u32 sid;
@@ -6244,20 +6244,27 @@ static int selinux_getprocattr(struct task_struct *p,
 			goto bad;
 	}
 
-	if (!strcmp(name, "current"))
+	switch (attr) {
+	case LSM_ATTR_CURRENT:
 		sid = __tsec->sid;
-	else if (!strcmp(name, "prev"))
+		break;
+	case LSM_ATTR_PREV:
 		sid = __tsec->osid;
-	else if (!strcmp(name, "exec"))
+		break;
+	case LSM_ATTR_EXEC:
 		sid = __tsec->exec_sid;
-	else if (!strcmp(name, "fscreate"))
+		break;
+	case LSM_ATTR_FSCREATE:
 		sid = __tsec->create_sid;
-	else if (!strcmp(name, "keycreate"))
+		break;
+	case LSM_ATTR_KEYCREATE:
 		sid = __tsec->keycreate_sid;
-	else if (!strcmp(name, "sockcreate"))
+		break;
+	case LSM_ATTR_SOCKCREATE:
 		sid = __tsec->sockcreate_sid;
-	else {
-		error = -EINVAL;
+		break;
+	default:
+		error = -EOPNOTSUPP;
 		goto bad;
 	}
 	rcu_read_unlock();
@@ -6275,7 +6282,7 @@ static int selinux_getprocattr(struct task_struct *p,
 	return error;
 }
 
-static int selinux_setprocattr(const char *name, void *value, size_t size)
+static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
 {
 	struct task_security_struct *tsec;
 	struct cred *new;
@@ -6286,23 +6293,31 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 	/*
 	 * Basic control over ability to set these attributes at all.
 	 */
-	if (!strcmp(name, "exec"))
+	switch (attr) {
+	case LSM_ATTR_EXEC:
 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
 				     PROCESS__SETEXEC, NULL);
-	else if (!strcmp(name, "fscreate"))
+		break;
+	case LSM_ATTR_FSCREATE:
 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
 				     PROCESS__SETFSCREATE, NULL);
-	else if (!strcmp(name, "keycreate"))
+		break;
+	case LSM_ATTR_KEYCREATE:
 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
 				     PROCESS__SETKEYCREATE, NULL);
-	else if (!strcmp(name, "sockcreate"))
+		break;
+	case LSM_ATTR_SOCKCREATE:
 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
 				     PROCESS__SETSOCKCREATE, NULL);
-	else if (!strcmp(name, "current"))
+		break;
+	case LSM_ATTR_CURRENT:
 		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
 				     PROCESS__SETCURRENT, NULL);
-	else
-		error = -EINVAL;
+		break;
+	default:
+		error = -EOPNOTSUPP;
+		break;
+	}
 	if (error)
 		return error;
 
@@ -6314,13 +6329,14 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 		}
 		error = security_context_to_sid(value, size,
 						&sid, GFP_KERNEL);
-		if (error == -EINVAL && !strcmp(name, "fscreate")) {
+		if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
 			if (!has_cap_mac_admin(true)) {
 				struct audit_buffer *ab;
 				size_t audit_size;
 
-				/* We strip a nul only if it is at the end, otherwise the
-				 * context contains a nul and we should audit that */
+				/* We strip a nul only if it is at the end,
+				 * otherwise the context contains a nul and
+				 * we should audit that */
 				if (str[size - 1] == '\0')
 					audit_size = size - 1;
 				else
@@ -6331,7 +6347,8 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 				if (!ab)
 					return error;
 				audit_log_format(ab, "op=fscreate invalid_context=");
-				audit_log_n_untrustedstring(ab, value, audit_size);
+				audit_log_n_untrustedstring(ab, value,
+							    audit_size);
 				audit_log_end(ab);
 
 				return error;
@@ -6354,11 +6371,11 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 	   checks and may_create for the file creation checks. The
 	   operation will then fail if the context is not permitted. */
 	tsec = selinux_cred(new);
-	if (!strcmp(name, "exec")) {
+	if (attr == LSM_ATTR_EXEC) {
 		tsec->exec_sid = sid;
-	} else if (!strcmp(name, "fscreate")) {
+	} else if (attr == LSM_ATTR_FSCREATE) {
 		tsec->create_sid = sid;
-	} else if (!strcmp(name, "keycreate")) {
+	} else if (attr == LSM_ATTR_KEYCREATE) {
 		if (sid) {
 			error = avc_has_perm(mysid, sid,
 					     SECCLASS_KEY, KEY__CREATE, NULL);
@@ -6366,9 +6383,9 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 				goto abort_change;
 		}
 		tsec->keycreate_sid = sid;
-	} else if (!strcmp(name, "sockcreate")) {
+	} else if (attr == LSM_ATTR_SOCKCREATE) {
 		tsec->sockcreate_sid = sid;
-	} else if (!strcmp(name, "current")) {
+	} else if (attr == LSM_ATTR_CURRENT) {
 		error = -EINVAL;
 		if (sid == 0)
 			goto abort_change;
@@ -6410,6 +6427,81 @@ static int selinux_setprocattr(const char *name, void *value, size_t size)
 	return error;
 }
 
+static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
+			       size_t *size, u32 flags)
+{
+	char *value;
+	size_t total_len;
+	int len;
+	int rc;
+
+	len = selinux_lsm_getattr(attr, current, &value);
+	if (len < 0)
+		return len;
+
+	total_len = ALIGN(struct_size(ctx, ctx, len), 8);
+
+	if (total_len > *size)
+		rc = -E2BIG;
+	else if (ctx)
+		rc = lsm_fill_user_ctx(ctx, value, len, LSM_ID_SELINUX, 0);
+	else
+		rc = 1;
+
+	*size = total_len;
+	if (rc < 0)
+		return rc;
+	return 1;
+}
+
+static int selinux_setselfattr(unsigned int __user attr,
+			       struct lsm_ctx __user *ctx, size_t __user size,
+			       u32 __user flags)
+{
+	struct lsm_ctx *lctx;
+	int rc;
+
+	lctx = kmalloc(size, GFP_KERNEL);
+	if (lctx == NULL)
+		return -ENOMEM;
+
+	if (copy_from_user(lctx, ctx, size))
+		rc = -EFAULT;
+	else if (lctx->ctx_len > size)
+		rc = -EINVAL;
+	else
+		rc = selinux_lsm_setattr(attr, lctx->ctx, lctx->ctx_len);
+
+	kfree(lctx);
+	if (rc > 0)
+		return 0;
+	return rc;
+}
+
+static int selinux_getprocattr(struct task_struct *p,
+			       const char *name, char **value)
+{
+	unsigned int attr = lsm_name_to_attr(name);
+	int rc;
+
+	if (attr) {
+		rc = selinux_lsm_getattr(attr, p, value);
+		if (rc != -EOPNOTSUPP)
+			return rc;
+	}
+
+	return -EINVAL;
+}
+
+static int selinux_setprocattr(const char *name, void *value, size_t size)
+{
+	int attr = lsm_name_to_attr(name);
+
+	if (attr)
+		return selinux_lsm_setattr(attr, value, size);
+	return -EINVAL;
+}
+
 static int selinux_ismaclabel(const char *name)
 {
 	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
@@ -7041,6 +7133,8 @@ static struct security_hook_list selinux_hooks[] __ro_after_init = {
 
 	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
 
+	LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
+	LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
 	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
 	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
 
-- 
2.40.1

[PATCH v11 11/11] LSM: selftests for Linux Security Module syscalls

[Casey Schaufler]

Add selftests for the three system calls supporting the LSM
infrastructure.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
 tools/testing/selftests/Makefile              |   1 +
 tools/testing/selftests/lsm/Makefile          |  12 +
 tools/testing/selftests/lsm/config            |   2 +
 .../selftests/lsm/lsm_get_self_attr_test.c    | 270 ++++++++++++++++++
 .../selftests/lsm/lsm_list_modules_test.c     | 153 ++++++++++
 .../selftests/lsm/lsm_set_self_attr_test.c    |  70 +++++
 6 files changed, 508 insertions(+)
 create mode 100644 tools/testing/selftests/lsm/Makefile
 create mode 100644 tools/testing/selftests/lsm/config
 create mode 100644 tools/testing/selftests/lsm/lsm_get_self_attr_test.c
 create mode 100644 tools/testing/selftests/lsm/lsm_list_modules_test.c
 create mode 100644 tools/testing/selftests/lsm/lsm_set_self_attr_test.c

diff --git a/tools/testing/selftests/Makefile b/tools/testing/selftests/Makefile
index 90a62cf75008..2b91df264ada 100644
--- a/tools/testing/selftests/Makefile
+++ b/tools/testing/selftests/Makefile
@@ -38,6 +38,7 @@ TARGETS += landlock
 TARGETS += lib
 TARGETS += livepatch
 TARGETS += lkdtm
+TARGETS += lsm
 TARGETS += membarrier
 TARGETS += memfd
 TARGETS += memory-hotplug
diff --git a/tools/testing/selftests/lsm/Makefile b/tools/testing/selftests/lsm/Makefile
new file mode 100644
index 000000000000..f39a75212b78
--- /dev/null
+++ b/tools/testing/selftests/lsm/Makefile
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# First run: make -C ../../../.. headers_install
+
+CFLAGS += -Wall -O2 $(KHDR_INCLUDES)
+
+TEST_GEN_PROGS := lsm_get_self_attr_test lsm_list_modules_test \
+		  lsm_set_self_attr_test
+
+include ../lib.mk
+
+$(TEST_GEN_PROGS):
diff --git a/tools/testing/selftests/lsm/config b/tools/testing/selftests/lsm/config
new file mode 100644
index 000000000000..afb887715f64
--- /dev/null
+++ b/tools/testing/selftests/lsm/config
@@ -0,0 +1,2 @@
+CONFIG_SYSFS=y
+CONFIG_SECURITY=y
diff --git a/tools/testing/selftests/lsm/lsm_get_self_attr_test.c b/tools/testing/selftests/lsm/lsm_get_self_attr_test.c
new file mode 100644
index 000000000000..a62524b17bf7
--- /dev/null
+++ b/tools/testing/selftests/lsm/lsm_get_self_attr_test.c
@@ -0,0 +1,270 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Linux Security Module infrastructure tests
+ * Tests for the lsm_get_self_attr system call
+ *
+ * Copyright © 2022 Casey Schaufler <casey@schaufler-ca.com>
+ * Copyright © 2022 Intel Corporation
+ */
+
+#define _GNU_SOURCE
+#include <linux/lsm.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include "../kselftest_harness.h"
+
+#define PROCATTR	"/proc/self/attr/"
+
+static int read_proc_attr(const char *attr, char *value, __kernel_size_t size)
+{
+	int fd;
+	int len;
+	char *path;
+
+	len = strlen(PROCATTR) + strlen(attr) + 1;
+	path = calloc(len, 1);
+	if (path == NULL)
+		return -1;
+	sprintf(path, "%s%s", PROCATTR, attr);
+
+	fd = open(path, O_RDONLY);
+	free(path);
+
+	if (fd < 0)
+		return -1;
+	len = read(fd, value, size);
+	if (len <= 0)
+		return -1;
+	close(fd);
+
+	path = strchr(value, '\n');
+	if (path)
+		*path = '\0';
+
+	return 0;
+}
+
+static struct lsm_ctx *next_ctx(struct lsm_ctx *ctxp)
+{
+	void *vp;
+
+	vp = (void *)ctxp + sizeof(*ctxp) + ctxp->ctx_len;
+	return (struct lsm_ctx *)vp;
+}
+
+TEST(size_null_lsm_get_self_attr)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	char *ctx = calloc(page_size, 1);
+
+	ASSERT_NE(NULL, ctx);
+	errno = 0;
+	ASSERT_EQ(-1, syscall(__NR_lsm_get_self_attr, LSM_ATTR_CURRENT, ctx,
+			      NULL, 0));
+	ASSERT_EQ(EINVAL, errno);
+
+	free(ctx);
+}
+
+TEST(ctx_null_lsm_get_self_attr)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	__kernel_size_t size = page_size;
+
+	ASSERT_NE(-1, syscall(__NR_lsm_get_self_attr, LSM_ATTR_CURRENT, NULL,
+			      &size, 0));
+	ASSERT_NE(1, size);
+}
+
+TEST(size_too_small_lsm_get_self_attr)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	char *ctx = calloc(page_size, 1);
+	__kernel_size_t size = 1;
+
+	ASSERT_NE(NULL, ctx);
+	errno = 0;
+	ASSERT_EQ(-1, syscall(__NR_lsm_get_self_attr, LSM_ATTR_CURRENT, ctx,
+			      &size, 0));
+	ASSERT_EQ(E2BIG, errno);
+	ASSERT_NE(1, size);
+
+	free(ctx);
+}
+
+TEST(flags_zero_lsm_get_self_attr)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	char *ctx = calloc(page_size, 1);
+	__kernel_size_t size = page_size;
+
+	ASSERT_NE(NULL, ctx);
+	errno = 0;
+	ASSERT_EQ(-1, syscall(__NR_lsm_get_self_attr, LSM_ATTR_CURRENT, ctx,
+			      &size, 1));
+	ASSERT_EQ(EINVAL, errno);
+	ASSERT_EQ(page_size, size);
+
+	free(ctx);
+}
+
+TEST(flags_overset_lsm_get_self_attr)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	char *ctx = calloc(page_size, 1);
+	__kernel_size_t size = page_size;
+
+	ASSERT_NE(NULL, ctx);
+	errno = 0;
+	ASSERT_EQ(-1, syscall(__NR_lsm_get_self_attr,
+			      LSM_ATTR_CURRENT | LSM_ATTR_PREV, ctx, &size, 0));
+	ASSERT_EQ(EOPNOTSUPP, errno);
+
+	free(ctx);
+}
+
+TEST(basic_lsm_get_self_attr)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	__kernel_size_t size = page_size;
+	struct lsm_ctx *ctx = calloc(page_size, 1);
+	struct lsm_ctx *tctx = NULL;
+	__u64 *syscall_lsms = calloc(page_size, 1);
+	char *attr = calloc(page_size, 1);
+	int cnt_current = 0;
+	int cnt_exec = 0;
+	int cnt_fscreate = 0;
+	int cnt_keycreate = 0;
+	int cnt_prev = 0;
+	int cnt_sockcreate = 0;
+	int lsmcount;
+	int count;
+	int i;
+
+	ASSERT_NE(NULL, ctx);
+	ASSERT_NE(NULL, syscall_lsms);
+
+	lsmcount = syscall(__NR_lsm_list_modules, syscall_lsms, &size, 0);
+	ASSERT_LE(1, lsmcount);
+
+	for (i = 0; i < lsmcount; i++) {
+		switch (syscall_lsms[i]) {
+		case LSM_ID_SELINUX:
+			cnt_current++;
+			cnt_exec++;
+			cnt_fscreate++;
+			cnt_keycreate++;
+			cnt_prev++;
+			cnt_sockcreate++;
+			break;
+		case LSM_ID_SMACK:
+			cnt_current++;
+			break;
+		case LSM_ID_APPARMOR:
+			cnt_current++;
+			cnt_exec++;
+			cnt_prev++;
+			break;
+		default:
+			break;
+		}
+	}
+
+	if (cnt_current) {
+		size = page_size;
+		count = syscall(__NR_lsm_get_self_attr, LSM_ATTR_CURRENT, ctx,
+				&size, 0);
+		ASSERT_EQ(cnt_current, count);
+		tctx = ctx;
+		ASSERT_EQ(0, read_proc_attr("current", attr, page_size));
+		ASSERT_EQ(0, strcmp((char *)tctx->ctx, attr));
+		for (i = 1; i < count; i++) {
+			tctx = next_ctx(tctx);
+			ASSERT_NE(0, strcmp((char *)tctx->ctx, attr));
+		}
+	}
+	if (cnt_exec) {
+		size = page_size;
+		count = syscall(__NR_lsm_get_self_attr, LSM_ATTR_EXEC, ctx,
+				&size, 0);
+		ASSERT_GE(cnt_exec, count);
+		if (count > 0) {
+			tctx = ctx;
+			if (read_proc_attr("exec", attr, page_size) == 0)
+				ASSERT_EQ(0, strcmp((char *)tctx->ctx, attr));
+		}
+		for (i = 1; i < count; i++) {
+			tctx = next_ctx(tctx);
+			ASSERT_NE(0, strcmp((char *)tctx->ctx, attr));
+		}
+	}
+	if (cnt_fscreate) {
+		size = page_size;
+		count = syscall(__NR_lsm_get_self_attr, LSM_ATTR_FSCREATE, ctx,
+				&size, 0);
+		ASSERT_GE(cnt_fscreate, count);
+		if (count > 0) {
+			tctx = ctx;
+			if (read_proc_attr("fscreate", attr, page_size) == 0)
+				ASSERT_EQ(0, strcmp((char *)tctx->ctx, attr));
+		}
+		for (i = 1; i < count; i++) {
+			tctx = next_ctx(tctx);
+			ASSERT_NE(0, strcmp((char *)tctx->ctx, attr));
+		}
+	}
+	if (cnt_keycreate) {
+		size = page_size;
+		count = syscall(__NR_lsm_get_self_attr, LSM_ATTR_KEYCREATE, ctx,
+				&size, 0);
+		ASSERT_GE(cnt_keycreate, count);
+		if (count > 0) {
+			tctx = ctx;
+			if (read_proc_attr("keycreate", attr, page_size) == 0)
+				ASSERT_EQ(0, strcmp((char *)tctx->ctx, attr));
+		}
+		for (i = 1; i < count; i++) {
+			tctx = next_ctx(tctx);
+			ASSERT_NE(0, strcmp((char *)tctx->ctx, attr));
+		}
+	}
+	if (cnt_prev) {
+		size = page_size;
+		count = syscall(__NR_lsm_get_self_attr, LSM_ATTR_PREV, ctx,
+				&size, 0);
+		ASSERT_GE(cnt_prev, count);
+		if (count > 0) {
+			tctx = ctx;
+			ASSERT_EQ(0, read_proc_attr("prev", attr, page_size));
+			ASSERT_EQ(0, strcmp((char *)tctx->ctx, attr));
+			for (i = 1; i < count; i++) {
+				tctx = next_ctx(tctx);
+				ASSERT_NE(0, strcmp((char *)tctx->ctx, attr));
+			}
+		}
+	}
+	if (cnt_sockcreate) {
+		size = page_size;
+		count = syscall(__NR_lsm_get_self_attr, LSM_ATTR_SOCKCREATE,
+				ctx, &size, 0);
+		ASSERT_GE(cnt_sockcreate, count);
+		if (count > 0) {
+			tctx = ctx;
+			if (read_proc_attr("sockcreate", attr, page_size) == 0)
+				ASSERT_EQ(0, strcmp((char *)tctx->ctx, attr));
+		}
+		for (i = 1; i < count; i++) {
+			tctx = next_ctx(tctx);
+			ASSERT_NE(0, strcmp((char *)tctx->ctx, attr));
+		}
+	}
+
+	free(ctx);
+	free(attr);
+	free(syscall_lsms);
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/lsm/lsm_list_modules_test.c b/tools/testing/selftests/lsm/lsm_list_modules_test.c
new file mode 100644
index 000000000000..871d516a7d7d
--- /dev/null
+++ b/tools/testing/selftests/lsm/lsm_list_modules_test.c
@@ -0,0 +1,153 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Linux Security Module infrastructure tests
+ * Tests for the lsm_list_modules system call
+ *
+ * Copyright © 2022 Casey Schaufler <casey@schaufler-ca.com>
+ * Copyright © 2022 Intel Corporation
+ */
+
+#define _GNU_SOURCE
+#include <linux/lsm.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include "../kselftest_harness.h"
+
+static int read_sysfs_lsms(char *lsms, __kernel_size_t size)
+{
+	FILE *fp;
+
+	fp = fopen("/sys/kernel/security/lsm", "r");
+	if (fp == NULL)
+		return -1;
+	if (fread(lsms, 1, size, fp) <= 0)
+		return -1;
+	fclose(fp);
+	return 0;
+}
+
+TEST(size_null_lsm_list_modules)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	char *syscall_lsms = calloc(page_size, 1);
+
+	ASSERT_NE(NULL, syscall_lsms);
+	errno = 0;
+	ASSERT_EQ(-1, syscall(__NR_lsm_list_modules, syscall_lsms, NULL, 0));
+	ASSERT_EQ(EFAULT, errno);
+
+	free(syscall_lsms);
+}
+
+TEST(ids_null_lsm_list_modules)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	__kernel_size_t size = page_size;
+
+	errno = 0;
+	ASSERT_EQ(-1, syscall(__NR_lsm_list_modules, NULL, &size, 0));
+	ASSERT_EQ(EFAULT, errno);
+	ASSERT_NE(1, size);
+}
+
+TEST(size_too_small_lsm_list_modules)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	char *syscall_lsms = calloc(page_size, 1);
+	__kernel_size_t size = 1;
+
+	ASSERT_NE(NULL, syscall_lsms);
+	errno = 0;
+	ASSERT_EQ(-1, syscall(__NR_lsm_list_modules, syscall_lsms, &size, 0));
+	ASSERT_EQ(E2BIG, errno);
+	ASSERT_NE(1, size);
+
+	free(syscall_lsms);
+}
+
+TEST(flags_set_lsm_list_modules)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	char *syscall_lsms = calloc(page_size, 1);
+	__kernel_size_t size = page_size;
+
+	ASSERT_NE(NULL, syscall_lsms);
+	errno = 0;
+	ASSERT_EQ(-1, syscall(__NR_lsm_list_modules, syscall_lsms, &size, 7));
+	ASSERT_EQ(EINVAL, errno);
+	ASSERT_EQ(page_size, size);
+
+	free(syscall_lsms);
+}
+
+TEST(correct_lsm_list_modules)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	__kernel_size_t size = page_size;
+	__u64 *syscall_lsms = calloc(page_size, 1);
+	char *sysfs_lsms = calloc(page_size, 1);
+	char *name;
+	char *cp;
+	int count;
+	int i;
+
+	ASSERT_NE(NULL, sysfs_lsms);
+	ASSERT_NE(NULL, syscall_lsms);
+	ASSERT_EQ(0, read_sysfs_lsms(sysfs_lsms, page_size));
+
+	count = syscall(__NR_lsm_list_modules, syscall_lsms, &size, 0);
+	ASSERT_LE(1, count);
+	cp = sysfs_lsms;
+	for (i = 0; i < count; i++) {
+		switch (syscall_lsms[i]) {
+		case LSM_ID_CAPABILITY:
+			name = "capability";
+			break;
+		case LSM_ID_SELINUX:
+			name = "selinux";
+			break;
+		case LSM_ID_SMACK:
+			name = "smack";
+			break;
+		case LSM_ID_TOMOYO:
+			name = "tomoyo";
+			break;
+		case LSM_ID_IMA:
+			name = "ima";
+			break;
+		case LSM_ID_APPARMOR:
+			name = "apparmor";
+			break;
+		case LSM_ID_YAMA:
+			name = "yama";
+			break;
+		case LSM_ID_LOADPIN:
+			name = "loadpin";
+			break;
+		case LSM_ID_SAFESETID:
+			name = "safesetid";
+			break;
+		case LSM_ID_LOCKDOWN:
+			name = "lockdown";
+			break;
+		case LSM_ID_BPF:
+			name = "bpf";
+			break;
+		case LSM_ID_LANDLOCK:
+			name = "landlock";
+			break;
+		default:
+			name = "INVALID";
+			break;
+		}
+		ASSERT_EQ(0, strncmp(cp, name, strlen(name)));
+		cp += strlen(name) + 1;
+	}
+
+	free(sysfs_lsms);
+	free(syscall_lsms);
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/lsm/lsm_set_self_attr_test.c b/tools/testing/selftests/lsm/lsm_set_self_attr_test.c
new file mode 100644
index 000000000000..ca538a703168
--- /dev/null
+++ b/tools/testing/selftests/lsm/lsm_set_self_attr_test.c
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Linux Security Module infrastructure tests
+ * Tests for the lsm_set_self_attr system call
+ *
+ * Copyright © 2022 Casey Schaufler <casey@schaufler-ca.com>
+ * Copyright © 2022 Intel Corporation
+ */
+
+#define _GNU_SOURCE
+#include <linux/lsm.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include "../kselftest_harness.h"
+
+TEST(ctx_null_lsm_set_self_attr)
+{
+	ASSERT_EQ(-1, syscall(__NR_lsm_set_self_attr, LSM_ATTR_CURRENT, NULL,
+			      sizeof(struct lsm_ctx), 0));
+}
+
+TEST(size_too_small_lsm_set_self_attr)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	struct lsm_ctx *ctx = calloc(page_size, 1);
+	__kernel_size_t size = page_size;
+
+	ASSERT_NE(NULL, ctx);
+	ASSERT_GE(1, syscall(__NR_lsm_get_self_attr, LSM_ATTR_CURRENT, ctx,
+			     &size, 0));
+	ASSERT_EQ(-1, syscall(__NR_lsm_set_self_attr, LSM_ATTR_CURRENT, ctx, 1,
+			      0));
+
+	free(ctx);
+}
+
+TEST(flags_zero_lsm_set_self_attr)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	char *ctx = calloc(page_size, 1);
+	__kernel_size_t size = page_size;
+
+	ASSERT_NE(NULL, ctx);
+	ASSERT_GE(1, syscall(__NR_lsm_get_self_attr, LSM_ATTR_CURRENT, ctx,
+			     &size, 0));
+	ASSERT_EQ(-1, syscall(__NR_lsm_set_self_attr, LSM_ATTR_CURRENT, ctx,
+			      size, 1));
+
+	free(ctx);
+}
+
+TEST(flags_overset_lsm_set_self_attr)
+{
+	const long page_size = sysconf(_SC_PAGESIZE);
+	char *ctx = calloc(page_size, 1);
+	__kernel_size_t size = page_size;
+	struct lsm_ctx *tctx = (struct lsm_ctx *)ctx;
+
+	ASSERT_NE(NULL, ctx);
+	ASSERT_GE(1, syscall(__NR_lsm_get_self_attr, LSM_ATTR_CURRENT, tctx,
+			     &size, 0));
+	ASSERT_EQ(-1, syscall(__NR_lsm_set_self_attr,
+			      LSM_ATTR_CURRENT | LSM_ATTR_PREV, tctx, size, 0));
+
+	free(ctx);
+}
+
+TEST_HARNESS_MAIN
-- 
2.40.1

Re: [PATCH v11 07/11] LSM: Helpers for attribute names and filling lsm_ctx

[Kees Cook]

On Fri, Jun 16, 2023 at 09:50:51AM -0700, Casey Schaufler wrote:
> Add lsm_name_to_attr(), which translates a text string to a
> LSM_ATTR value if one is available.
> 
> Add lsm_fill_user_ctx(), which fills a struct lsm_ctx, including
> the trailing attribute value.
> 
> All are used in module specific components of LSM system calls.
> 
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook

Re: [PATCH v11 11/11] LSM: selftests for Linux Security Module syscalls

[Kees Cook]

On Fri, Jun 16, 2023 at 09:50:55AM -0700, Casey Schaufler wrote:
> Add selftests for the three system calls supporting the LSM
> infrastructure.
> 
> Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook

Re: [PATCH v11 00/11] LSM: Three basic syscalls

[Jay Freyensee]

On 6/16/23 9:50 AM, Casey Schaufler wrote:
> Add three system calls for the Linux Security Module ABI.
>
> lsm_get_self_attr() provides the security module specific attributes
> that have previously been visible in the /proc/self/attr directory.
> For each security module that uses the specified attribute on the
> current process the system call will return an LSM identifier and
> the value of the attribute. The LSM and attribute identifier values
> are defined in include/uapi/linux/lsm.h
>
> LSM identifiers are simple integers and reflect the order in which
> the LSM was added to the mainline kernel. This is a convention, not
> a promise of the API. LSM identifiers below the value of 100 are
> reserved for unspecified future uses. That could include information
> about the security infrastructure itself, or about how multiple LSMs
> might interact with each other.
>
> A new LSM hook security_getselfattr() is introduced to get the
> required information from the security modules. This is similar
> to the existing security_getprocattr() hook, but specifies the
> format in which string data is returned and requires the module
> to put the information into a userspace destination.
>
> lsm_set_self_attr() changes the specified LSM attribute. Only one
> attribute can be changed at a time, and then only if the specified
> security module allows the change.
>
> A new LSM hook security_setselfattr() is introduced to set the
> required information in the security modules. This is similar
> to the existing security_setprocattr() hook, but specifies the
> format in which string data is presented and requires the module
> to get the information from a userspace destination.
>
> lsm_list_modules() provides the LSM identifiers, in order, of the
> security modules that are active on the system. This has been
> available in the securityfs file /sys/kernel/security/lsm.
Active or available?

If I use landlock's documentation example:

Jun 07 10:37:11 fedora kernel: LSM: initializing 
lsm=lockdown,capability,yama,integrity,selinux,bpf>
Jun 07 10:37:11 fedora kernel: landlock: Up and running.

My interpretation of the two log lines is the first line tells me 
landlock is available on the distro (fedora this case), but the second 
line tells me landlock is now active. Thus the lsm available list may be 
different than the lsm active list.


So is lsm_list_modules() going to tell me just what lsm's are available 
in a distro for use, or is it going to tell me what lsm's are available 
_and_ active?

Thanks,

Jay

Re: [PATCH v11 00/11] LSM: Three basic syscalls

[Casey Schaufler]

On 6/23/2023 6:10 PM, Jay Freyensee wrote:
>
> On 6/16/23 9:50 AM, Casey Schaufler wrote:
>> Add three system calls for the Linux Security Module ABI.
>>
>> lsm_get_self_attr() provides the security module specific attributes
>> that have previously been visible in the /proc/self/attr directory.
>> For each security module that uses the specified attribute on the
>> current process the system call will return an LSM identifier and
>> the value of the attribute. The LSM and attribute identifier values
>> are defined in include/uapi/linux/lsm.h
>>
>> LSM identifiers are simple integers and reflect the order in which
>> the LSM was added to the mainline kernel. This is a convention, not
>> a promise of the API. LSM identifiers below the value of 100 are
>> reserved for unspecified future uses. That could include information
>> about the security infrastructure itself, or about how multiple LSMs
>> might interact with each other.
>>
>> A new LSM hook security_getselfattr() is introduced to get the
>> required information from the security modules. This is similar
>> to the existing security_getprocattr() hook, but specifies the
>> format in which string data is returned and requires the module
>> to put the information into a userspace destination.
>>
>> lsm_set_self_attr() changes the specified LSM attribute. Only one
>> attribute can be changed at a time, and then only if the specified
>> security module allows the change.
>>
>> A new LSM hook security_setselfattr() is introduced to set the
>> required information in the security modules. This is similar
>> to the existing security_setprocattr() hook, but specifies the
>> format in which string data is presented and requires the module
>> to get the information from a userspace destination.
>>
>> lsm_list_modules() provides the LSM identifiers, in order, of the
>> security modules that are active on the system. This has been
>> available in the securityfs file /sys/kernel/security/lsm.
> Active or available?

Active. Security modules are registered during init time.
There isn't really a notion of "available" since you can't
enable or disable them dynamically.

>
> If I use landlock's documentation example:
>
> Jun 07 10:37:11 fedora kernel: LSM: initializing
> lsm=lockdown,capability,yama,integrity,selinux,bpf>
> Jun 07 10:37:11 fedora kernel: landlock: Up and running.
>
> My interpretation of the two log lines is the first line tells me
> landlock is available on the distro (fedora this case), but the second
> line tells me landlock is now active. Thus the lsm available list may
> be different than the lsm active list.

Your "available" list would depend on which modules are compiled in.
There is no explicit mechanism provided to get that list. There isn't
anything interesting you could do with it on a running system.

>
> So is lsm_list_modules() going to tell me just what lsm's are
> available in a distro for use, or is it going to tell me what lsm's
> are available _and_ active?

As documented, its going to tell you which are active.
You can infer that a module is available if it is active.
You cannot infer that a module isn't "available", that is,
isn't compiled in, if it isn't active.

>
> Thanks,
>
> Jay
>