[PATCH] minor audit updates

Just a few minor proposed updates.  Only the last one will
actually affect behavior.  The rest are just misleading
code.

Several AUDIT_SET functions return 'old' value, but only
return value <0 is checked for.  So just return 0.

propagate audit_set_rate_limit and audit_set_backlog_limit
error values

In audit_buffer_free, the audit_freelist_count was being
incremented even when we discard the return buffer, so
audit_freelist_count can end up wrong.  This could cause
the actual freelist to shrink over time, eventually
threatening to degrate audit performance.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 10 insertions, 9 deletions

diff --git a/kernel/audit.c b/kernel/audit.c
index bb20922d08cc..0738a4b290e6 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -251,7 +251,7 @@ static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sid)
                         "audit_rate_limit=%d old=%d by auid=%u",
                         limit, old, loginuid);
         audit_rate_limit = limit;
-        return old;
+        return 0;
 }
 
 static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sid)
@@ -274,7 +274,7 @@ static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sid)
                         "audit_backlog_limit=%d old=%d by auid=%u",
                         limit, old, loginuid);
         audit_backlog_limit = limit;
-        return old;
+        return 0;
 }
 
 static int audit_set_enabled(int state, uid_t loginuid, u32 sid)
@@ -300,7 +300,7 @@ static int audit_set_enabled(int state, uid_t loginuid, u32 sid)
                         "audit_enabled=%d old=%d by auid=%u",
                         state, old, loginuid);
         audit_enabled = state;
-        return old;
+        return 0;
 }
 
 static int audit_set_failure(int state, uid_t loginuid, u32 sid)
@@ -328,7 +328,7 @@ static int audit_set_failure(int state, uid_t loginuid, u32 sid)
                         "audit_failure=%d old=%d by auid=%u",
                         state, old, loginuid);
         audit_failure = state;
-        return old;
+        return 0;
 }
 
 static int kauditd_thread(void *dummy)
@@ -364,7 +364,6 @@ static int kauditd_thread(void *dummy)
                         remove_wait_queue(&kauditd_wait, &wait);
                 }
         }
-        return 0;
 }
 
 int audit_send_list(void *_dest)
@@ -551,10 +550,10 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
                         audit_pid = status_get->pid;
                 }
                 if (status_get->mask & AUDIT_STATUS_RATE_LIMIT)
-                        audit_set_rate_limit(status_get->rate_limit,
+                        err = audit_set_rate_limit(status_get->rate_limit,
                                                          loginuid, sid);
                 if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT)
-                        audit_set_backlog_limit(status_get->backlog_limit,
+                        err = audit_set_backlog_limit(status_get->backlog_limit,
                                                         loginuid, sid);
                 break;
         case AUDIT_USER:
@@ -727,10 +726,12 @@ static void audit_buffer_free(struct audit_buffer *ab)
                 kfree_skb(ab->skb);
 
         spin_lock_irqsave(&audit_freelist_lock, flags);
-        if (++audit_freelist_count > AUDIT_MAXFREE)
+        if (audit_freelist_count > AUDIT_MAXFREE)
                 kfree(ab);
-        else
+        else {
+                audit_freelist_count++;
                 list_add(&ab->list, &audit_freelist);
+        }
         spin_unlock_irqrestore(&audit_freelist_lock, flags);
 }