From: Casey Schaufler <casey@schaufler-ca.com>
To: casey.schaufler@intel.com, jmorris@namei.org,
linux-security-module@vger.kernel.org, selinux@vger.kernel.org
Cc: john.johansen@canonical.com, linux-kernel@vger.kernel.org,
linux-audit@redhat.com, sds@tycho.nsa.gov
Subject: [PATCH v30 26/28] Audit: Add record for multiple object security contexts
Date: Tue, 23 Nov 2021 17:43:30 -0800 [thread overview]
Message-ID: <20211124014332.36128-27-casey@schaufler-ca.com> (raw)
In-Reply-To: <20211124014332.36128-1-casey@schaufler-ca.com>
Create a new audit record AUDIT_MAC_OBJ_CONTEXTS.
An example of the MAC_OBJ_CONTEXTS (1421) record is:
type=UNKNOWN[1421]
msg=audit(1601152467.009:1050):
obj_selinux="unconfined_u:object_r:user_home_t:s0"
When an audit event includes a AUDIT_MAC_OBJ_CONTEXTS record
the "obj=" field in other records in the event will be "obj=?".
A AUDIT_MAC_OBJ_CONTEXTS record is supplied when the system has
multiple security modules that may make access decisions based
on an object security context.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
---
include/linux/audit.h | 5 ++++
include/uapi/linux/audit.h | 1 +
kernel/audit.c | 61 ++++++++++++++++++++++++++++++++++++++
kernel/auditsc.c | 37 ++++-------------------
4 files changed, 72 insertions(+), 32 deletions(-)
diff --git a/include/linux/audit.h b/include/linux/audit.h
index 943584128399..8381afb4f49e 100644
--- a/include/linux/audit.h
+++ b/include/linux/audit.h
@@ -192,6 +192,8 @@ extern void audit_log_path_denied(int type,
extern void audit_log_lost(const char *message);
extern int audit_log_task_context(struct audit_buffer *ab);
+extern void audit_log_object_context(struct audit_buffer *ab,
+ struct lsmblob *blob);
extern void audit_log_task_info(struct audit_buffer *ab);
extern int audit_update_lsm_rules(void);
@@ -255,6 +257,9 @@ static inline int audit_log_task_context(struct audit_buffer *ab)
{
return 0;
}
+static inline void audit_log_object_context(struct audit_buffer *ab,
+ struct lsmblob *blob);
+{ }
static inline void audit_log_task_info(struct audit_buffer *ab)
{ }
diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h
index 86ad3da4f0d4..116566d0fc03 100644
--- a/include/uapi/linux/audit.h
+++ b/include/uapi/linux/audit.h
@@ -144,6 +144,7 @@
#define AUDIT_MAC_CALIPSO_ADD 1418 /* NetLabel: add CALIPSO DOI entry */
#define AUDIT_MAC_CALIPSO_DEL 1419 /* NetLabel: del CALIPSO DOI entry */
#define AUDIT_MAC_TASK_CONTEXTS 1420 /* Multiple LSM task contexts */
+#define AUDIT_MAC_OBJ_CONTEXTS 1421 /* Multiple LSM objext contexts */
#define AUDIT_FIRST_KERN_ANOM_MSG 1700
#define AUDIT_LAST_KERN_ANOM_MSG 1799
diff --git a/kernel/audit.c b/kernel/audit.c
index 6c93545a14f3..55fdcc2c88e4 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -199,6 +199,7 @@ struct audit_context_entry {
int type; /* Audit record type */
union {
struct lsmblob mac_task_context;
+ struct lsmblob mac_obj_context;
};
};
@@ -2190,6 +2191,44 @@ int audit_log_task_context(struct audit_buffer *ab)
}
EXPORT_SYMBOL(audit_log_task_context);
+void audit_log_object_context(struct audit_buffer *ab, struct lsmblob *blob)
+{
+ struct audit_context_entry *ace;
+ struct lsmcontext context;
+ int error;
+
+ if (!lsm_multiple_contexts()) {
+ error = security_secid_to_secctx(blob, &context, LSMBLOB_FIRST);
+ if (error) {
+ if (error != -EINVAL)
+ goto error_path;
+ return;
+ }
+ audit_log_format(ab, " obj=%s", context.context);
+ security_release_secctx(&context);
+ return;
+ }
+ /*
+ * If there is more than one security module that has a
+ * object "context" it's necessary to put the object data
+ * into a separate record to maintain compatibility.
+ */
+ audit_log_format(ab, " obj=?");
+ ace = kzalloc(sizeof(*ace), GFP_KERNEL);
+ if (ace) {
+ INIT_LIST_HEAD(&ace->list);
+ ace->type = AUDIT_MAC_OBJ_CONTEXTS;
+ ace->mac_obj_context = *blob;
+ list_add(&ace->list, &ab->aux_records);
+ return;
+ }
+ error = -ENOMEM;
+
+error_path:
+ audit_panic("error in audit_log_object_context");
+}
+EXPORT_SYMBOL(audit_log_object_context);
+
void audit_log_d_path_exe(struct audit_buffer *ab,
struct mm_struct *mm)
{
@@ -2497,6 +2536,28 @@ void audit_log_end(struct audit_buffer *ab)
}
}
break;
+ case AUDIT_MAC_OBJ_CONTEXTS:
+ for (i = 0; i < LSMBLOB_ENTRIES; i++) {
+ if (entry->mac_obj_context.secid[i] == 0)
+ continue;
+ rc = security_secid_to_secctx(
+ &entry->mac_obj_context,
+ &lcontext, i);
+ if (rc) {
+ if (rc != -EINVAL)
+ audit_panic("error in audit_log_end");
+ audit_log_format(mab, "%sobj_%s=\"?\"",
+ i ? " " : "",
+ lsm_slot_to_name(i));
+ } else {
+ audit_log_format(mab, "%sobj_%s=\"%s\"",
+ i ? " " : "",
+ lsm_slot_to_name(i),
+ lcontext.context);
+ security_release_secctx(&lcontext);
+ }
+ }
+ break;
default:
audit_panic("Unknown type in audit_log_end");
break;
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index c128f7e73e89..dc8531a79174 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -1111,7 +1111,6 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
struct lsmblob *blob, char *comm)
{
struct audit_buffer *ab;
- struct lsmcontext lsmctx;
int rc = 0;
ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
@@ -1121,15 +1120,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
from_kuid(&init_user_ns, auid),
from_kuid(&init_user_ns, uid), sessionid);
- if (lsmblob_is_set(blob)) {
- if (security_secid_to_secctx(blob, &lsmctx, LSMBLOB_FIRST)) {
- audit_log_format(ab, " obj=(none)");
- rc = 1;
- } else {
- audit_log_format(ab, " obj=%s", lsmctx.context);
- security_release_secctx(&lsmctx);
- }
- }
+ if (lsmblob_is_set(blob))
+ audit_log_object_context(ab, blob);
audit_log_format(ab, " ocomm=");
audit_log_untrustedstring(ab, comm);
audit_log_end(ab);
@@ -1364,18 +1356,10 @@ static void show_special(struct audit_context *context, int *call_panic)
from_kgid(&init_user_ns, context->ipc.gid),
context->ipc.mode);
if (osid) {
- struct lsmcontext lsmcxt;
struct lsmblob blob;
lsmblob_init(&blob, osid);
- if (security_secid_to_secctx(&blob, &lsmcxt,
- LSMBLOB_FIRST)) {
- audit_log_format(ab, " osid=%u", osid);
- *call_panic = 1;
- } else {
- audit_log_format(ab, " obj=%s", lsmcxt.context);
- security_release_secctx(&lsmcxt);
- }
+ audit_log_object_context(ab, &blob);
}
if (context->ipc.has_perm) {
audit_log_end(ab);
@@ -1527,19 +1511,8 @@ static void audit_log_name(struct audit_context *context, struct audit_names *n,
from_kgid(&init_user_ns, n->gid),
MAJOR(n->rdev),
MINOR(n->rdev));
- if (lsmblob_is_set(&n->lsmblob)) {
- struct lsmcontext lsmctx;
-
- if (security_secid_to_secctx(&n->lsmblob, &lsmctx,
- LSMBLOB_FIRST)) {
- audit_log_format(ab, " osid=?");
- if (call_panic)
- *call_panic = 2;
- } else {
- audit_log_format(ab, " obj=%s", lsmctx.context);
- security_release_secctx(&lsmctx);
- }
- }
+ if (lsmblob_is_set(&n->lsmblob))
+ audit_log_object_context(ab, &n->lsmblob);
/* log the audit_names record type */
switch (n->type) {
--
2.31.1
--
Linux-audit mailing list
Linux-audit@redhat.com
https://listman.redhat.com/mailman/listinfo/linux-audit
next prev parent reply other threads:[~2021-11-24 2:12 UTC|newest]
Thread overview: 40+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20211124014332.36128-1-casey.ref@schaufler-ca.com>
2021-11-24 1:43 ` [PATCH v30 00/28] LSM: Module stacking for AppArmor Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 01/28] integrity: disassociate ima_filter_rule from security_audit_rule Casey Schaufler
2021-12-06 2:43 ` Paul Moore
2021-11-24 1:43 ` [PATCH v30 02/28] LSM: Infrastructure management of the sock security Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 03/28] LSM: Add the lsmblob data structure Casey Schaufler
2021-12-06 2:44 ` Paul Moore
2021-11-24 1:43 ` [PATCH v30 04/28] LSM: provide lsm name and id slot mappings Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 05/28] IMA: avoid label collisions with stacked LSMs Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 06/28] LSM: Use lsmblob in security_audit_rule_match Casey Schaufler
2021-11-24 13:19 ` kernel test robot
2021-12-06 2:44 ` Paul Moore
2021-11-24 1:43 ` [PATCH v30 07/28] LSM: Use lsmblob in security_kernel_act_as Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 08/28] LSM: Use lsmblob in security_secctx_to_secid Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 09/28] LSM: Use lsmblob in security_secid_to_secctx Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 10/28] LSM: Use lsmblob in security_ipc_getsecid Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 11/28] LSM: Use lsmblob in security_task_getsecid Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 12/28] LSM: Use lsmblob in security_inode_getsecid Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 13/28] LSM: Use lsmblob in security_cred_getsecid Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 14/28] LSM: Specify which LSM to display Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 15/28] LSM: Ensure the correct LSM context releaser Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 16/28] LSM: Use lsmcontext in security_secid_to_secctx Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 17/28] LSM: Use lsmcontext in security_inode_getsecctx Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 18/28] LSM: security_secid_to_secctx in netlink netfilter Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 19/28] NET: Store LSM netlabel data in a lsmblob Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 20/28] binder: Pass LSM identifier for confirmation Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 21/28] LSM: Extend security_secid_to_secctx to include module selection Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 22/28] Audit: Keep multiple LSM data in audit_names Casey Schaufler
2021-12-06 2:44 ` Paul Moore
2021-11-24 1:43 ` [PATCH v30 23/28] Audit: Create audit_stamp structure Casey Schaufler
2021-12-06 2:44 ` Paul Moore
2021-11-24 1:43 ` [PATCH v30 24/28] Audit: Add framework for auxiliary records Casey Schaufler
2021-12-06 2:45 ` Paul Moore
2021-11-24 1:43 ` [PATCH v30 25/28] Audit: Add record for multiple task security contexts Casey Schaufler
2021-12-06 2:45 ` Paul Moore
2021-11-24 1:43 ` Casey Schaufler [this message]
2021-11-24 7:41 ` [PATCH v30 26/28] Audit: Add record for multiple object " kernel test robot
2021-11-24 13:40 ` kernel test robot
2021-12-06 2:45 ` Paul Moore
2021-11-24 1:43 ` [PATCH v30 27/28] LSM: Add /proc attr entry for full LSM context Casey Schaufler
2021-11-24 1:43 ` [PATCH v30 28/28] AppArmor: Remove the exclusive flag Casey Schaufler
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