From ce3f8ea53c295931bd3fcdabbcf8a77b5967fa7c Mon Sep 17 00:00:00 2001
From: Dan Dennedy <dan@dennedy.org>
Date: Thu, 21 Mar 2013 19:42:45 -0700
Subject: [PATCH] Make avformat_lockmgr() safer by setting mutex pointer NULL.

---
 src/modules/avformat/factory.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/modules/avformat/factory.c b/src/modules/avformat/factory.c
index a2735377..179eb3c7 100644
--- a/src/modules/avformat/factory.c
+++ b/src/modules/avformat/factory.c
@@ -66,17 +66,22 @@ static int avformat_lockmgr(void **mutex, enum AVLockOp op)
    {
    case AV_LOCK_CREATE:
       *pmutex = (pthread_mutex_t*) malloc(sizeof(pthread_mutex_t));
+       if (!*pmutex) return -1;
        pthread_mutex_init(*pmutex, NULL);
        break;
    case AV_LOCK_OBTAIN:
+       if (!*pmutex) return -1;
        pthread_mutex_lock(*pmutex);
        break;
    case AV_LOCK_RELEASE:
+       if (!*pmutex) return -1;
        pthread_mutex_unlock(*pmutex);
        break;
    case AV_LOCK_DESTROY:
+       if (!*pmutex) return -1;
        pthread_mutex_destroy(*pmutex);
        free(*pmutex);
+       *pmutex = NULL;
        break;
    }
 
-- 
2.39.2