tracing/user_events: Hold event_mutex during dyn_event_add

Make sure the event_mutex is properly held during dyn_event_add call. This is required when adding dynamic events. Link: https://lkml.kernel.org/r/[email protected] Reported-by: Mathieu Desnoyers <[email protected]> Signed-off-by: Beau Belgrave <[email protected]> Acked-by: Masami Hiramatsu <[email protected]> Signed-off-by: Steven Rostedt (Google) <[email protected]>
wafgo · Apr 2, 2022 · efe34e9 · efe34e9
1 parent bed5b60
commit efe34e9
Showing 1 changed file with 6 additions and 2 deletions.
diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c
@@ -1165,11 +1165,11 @@ static int user_event_parse(char *name, char *args, char *flags,
 #endif
 
 	mutex_lock(&event_mutex);
+
 	ret = user_event_trace_register(user);
-	mutex_unlock(&event_mutex);
 
 	if (ret)
-		goto put_user;
+		goto put_user_lock;
 
 	user->index = index;
 
@@ -1181,8 +1181,12 @@ static int user_event_parse(char *name, char *args, char *flags,
 	set_bit(user->index, page_bitmap);
 	hash_add(register_table, &user->node, key);
 
+	mutex_unlock(&event_mutex);
+
 	*newuser = user;
 	return 0;
+put_user_lock:
+	mutex_unlock(&event_mutex);
 put_user:
 	user_event_destroy_fields(user);
 	user_event_destroy_validators(user);