audit: track the owner of the command mutex ourselves

Evidently the __mutex_owner() function was never intended for use
outside the core mutex code, so build a thing locking wrapper around
the mutex code which allows us to track the mutex owner.

One, arguably positive, side effect is that this allows us to hide
the audit_cmd_mutex inside of kernel/audit.c behind the lock/unlock
functions.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c
index fd353120e0d9..67e6956c0b61 100644
--- a/kernel/audit_tree.c
+++ b/kernel/audit_tree.c
@@ -709,7 +709,7 @@ static int prune_tree_thread(void *unused)
                         schedule();
                 }
 
-                mutex_lock(&audit_cmd_mutex);
+                audit_ctl_lock();
                 mutex_lock(&audit_filter_mutex);
 
                 while (!list_empty(&prune_list)) {
@@ -727,7 +727,7 @@ static int prune_tree_thread(void *unused)
                 }
 
                 mutex_unlock(&audit_filter_mutex);
-                mutex_unlock(&audit_cmd_mutex);
+                audit_ctl_unlock();
         }
         return 0;
 }
@@ -924,7 +924,7 @@ static void audit_schedule_prune(void)
  */
 void audit_kill_trees(struct list_head *list)
 {
-        mutex_lock(&audit_cmd_mutex);
+        audit_ctl_lock();
         mutex_lock(&audit_filter_mutex);
 
         while (!list_empty(list)) {
@@ -942,7 +942,7 @@ void audit_kill_trees(struct list_head *list)
         }
 
         mutex_unlock(&audit_filter_mutex);
-        mutex_unlock(&audit_cmd_mutex);
+        audit_ctl_unlock();
 }
 
 /*