From: Paul Moore paul@paul-moore.com
commit 8ac68dc455d9d18241d44b96800d73229029ed34 upstream.
Unfortunately the commit listed in the subject line above failed to ensure that the task's audit_context was properly initialized/set before enabling the "accompanying records". Depending on the situation, the resulting audit_context could have invalid values in some of it's fields which could cause a kernel panic/oops when the task/syscall exists and the audit records are generated.
We will revisit the original patch, with the necessary fixes, in a future kernel but right now we just want to fix the kernel panic with the least amount of added risk.
Cc: stable@vger.kernel.org Fixes: 1320a4052ea1 ("audit: trigger accompanying records when no rules present") Reported-by: j2468h@googlemail.com Signed-off-by: Paul Moore paul@paul-moore.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- kernel/audit.c | 1 - kernel/audit.h | 8 -------- kernel/auditsc.c | 3 +++ 3 files changed, 3 insertions(+), 9 deletions(-)
--- a/kernel/audit.c +++ b/kernel/audit.c @@ -1811,7 +1811,6 @@ struct audit_buffer *audit_log_start(str }
audit_get_stamp(ab->ctx, &t, &serial); - audit_clear_dummy(ab->ctx); audit_log_format(ab, "audit(%llu.%03lu:%u): ", (unsigned long long)t.tv_sec, t.tv_nsec/1000000, serial);
--- a/kernel/audit.h +++ b/kernel/audit.h @@ -290,13 +290,6 @@ extern int audit_signal_info_syscall(str extern void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx); extern struct list_head *audit_killed_trees(void); - -static inline void audit_clear_dummy(struct audit_context *ctx) -{ - if (ctx) - ctx->dummy = 0; -} - #else /* CONFIG_AUDITSYSCALL */ #define auditsc_get_stamp(c, t, s) 0 #define audit_put_watch(w) {} @@ -330,7 +323,6 @@ static inline int audit_signal_info_sysc }
#define audit_filter_inodes(t, c) AUDIT_DISABLED -#define audit_clear_dummy(c) {} #endif /* CONFIG_AUDITSYSCALL */
extern char *audit_unpack_string(void **bufp, size_t *remain, size_t len); --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -1406,6 +1406,9 @@ static void audit_log_proctitle(void) struct audit_context *context = audit_context(); struct audit_buffer *ab;
+ if (!context || context->dummy) + return; + ab = audit_log_start(context, GFP_KERNEL, AUDIT_PROCTITLE); if (!ab) return; /* audit_panic or being filtered */