[ Upstream commit 95e0b46fcebd7dbf6850dee96046e4c4ddc7f69c ]
module.name will be allocated unconditionally when auditing load module, and audit_log_start() can fail with other reasons, or audit_log_exit maybe not called, caused module.name is not freed
so free module.name in audit_free_context and __audit_syscall_exit
unreferenced object 0xffff88af90837d20 (size 8): comm "modprobe", pid 1036, jiffies 4294704867 (age 3069.138s) hex dump (first 8 bytes): 69 78 67 62 65 00 ff ff ixgbe... backtrace: [<0000000008da28fe>] __audit_log_kern_module+0x33/0x80 [<00000000c1491e61>] load_module+0x64f/0x3850 [<000000007fc9ae3f>] __do_sys_init_module+0x218/0x250 [<0000000000d4a478>] do_syscall_64+0x117/0x400 [<000000004924ded8>] entry_SYSCALL_64_after_hwframe+0x49/0xbe [<000000007dc331dd>] 0xffffffffffffffff
Fixes: ca86cad7380e3 ("audit: log module name on init_module") Signed-off-by: Zhang Yu zhangyu31@baidu.com Signed-off-by: Li RongQing lirongqing@baidu.com [PM: manual merge fixup in __audit_syscall_exit()] Signed-off-by: Paul Moore paul@paul-moore.com Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/auditsc.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/kernel/auditsc.c b/kernel/auditsc.c index d1eab1d4a930e..fa7b8047aab89 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -840,6 +840,13 @@ static inline void audit_proctitle_free(struct audit_context *context) context->proctitle.len = 0; }
+static inline void audit_free_module(struct audit_context *context) +{ + if (context->type == AUDIT_KERN_MODULE) { + kfree(context->module.name); + context->module.name = NULL; + } +} static inline void audit_free_names(struct audit_context *context) { struct audit_names *n, *next; @@ -923,6 +930,7 @@ int audit_alloc(struct task_struct *tsk)
static inline void audit_free_context(struct audit_context *context) { + audit_free_module(context); audit_free_names(context); unroll_tree_refs(context, NULL, 0); free_tree_refs(context); @@ -1266,7 +1274,6 @@ static void show_special(struct audit_context *context, int *call_panic) audit_log_format(ab, "name="); if (context->module.name) { audit_log_untrustedstring(ab, context->module.name); - kfree(context->module.name); } else audit_log_format(ab, "(null)");
@@ -1697,6 +1704,7 @@ void __audit_syscall_exit(int success, long return_code) context->in_syscall = 0; context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
+ audit_free_module(context); audit_free_names(context); unroll_tree_refs(context, NULL, 0); audit_free_aux(context);