audit: get rid of *NO* daemon at audit_pid=0 message

kauditd_send_skb is called after audit_pid was checked to be non-zero.

However, it can be set to 0 due to auditd exiting while kauditd_send_skb
is still executed and this can result in a spurious warning about missing
auditd.

Re-check audit_pid before printing the message.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: linux-kernel@vger.kernel.org
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/kernel/audit.c b/kernel/audit.c
index 72bc1d0d1d0d..2dc757354693 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -410,10 +410,12 @@ static void kauditd_send_skb(struct sk_buff *skb)
         err = netlink_unicast(audit_sock, skb, audit_nlk_portid, 0);
         if (err < 0) {
                 BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */
-                printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
-                audit_log_lost("auditd disappeared\n");
-                audit_pid = 0;
-                audit_sock = NULL;
+                if (audit_pid) {
+                        printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
+                        audit_log_lost("auditd disappeared\n");
+                        audit_pid = 0;
+                        audit_sock = NULL;
+                }
                 /* we might get lucky and get this in the next auditd */
                 audit_hold_skb(skb);
         } else