[PATCH 3.5 51/90] audit: printk USER_AVC messages when audit isn't enabled
3.5.7.27 -stable review patch. If anyone has any objections, please let me know.
------------------
From: Tyler Hicks <tyhicks(a)canonical.com>
commit 0868a5e150bc4c47e7a003367cd755811eb41e0b upstream.
When the audit=1 kernel parameter is absent and auditd is not running,
AUDIT_USER_AVC messages are being silently discarded.
AUDIT_USER_AVC messages should be sent to userspace using printk(), as
mentioned in the commit message of 4a4cd633 ("AUDIT: Optimise the
audit-disabled case for discarding user messages").
When audit_enabled is 0, audit_receive_msg() discards all user messages
except for AUDIT_USER_AVC messages. However, audit_log_common_recv_msg()
refuses to allocate an audit_buffer if audit_enabled is 0. The fix is to
special case AUDIT_USER_AVC messages in both functions.
It looks like commit 50397bd1 ("[AUDIT] clean up audit_receive_msg()")
introduced this bug.
Signed-off-by: Tyler Hicks <tyhicks(a)canonical.com>
Cc: Al Viro <viro(a)zeniv.linux.org.uk>
Cc: Eric Paris <eparis(a)redhat.com>
Cc: linux-audit(a)redhat.com
Acked-by: Kees Cook <keescook(a)chromium.org>
Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com>
Signed-off-by: Eric Paris <eparis(a)redhat.com>
[ luis: backported to 3.5: adjusted context ]
Signed-off-by: Luis Henriques <luis.henriques(a)canonical.com>
---
kernel/audit.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/audit.c b/kernel/audit.c
index 5917dfe..f02d3fc 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -625,7 +625,7 @@ static int audit_log_common_recv_msg(struct audit_buffer **ab, u16
msg_type,
char *ctx = NULL;
u32 len;
- if (!audit_enabled) {
+ if (!audit_enabled && msg_type != AUDIT_USER_AVC) {
*ab = NULL;
return rc;
}
--
1.8.3.2