[FFmpeg-devel] [PATCH] avformat/demux: Fix segfault due to avcodec_open2 failure

[Pavel Koshevoy]

Fixes 'ffprobe 1_poc.mp4' segfault introduced with
commit 0021484d05f9b0f032fa319399de6e24eea0c04f
---
 libavformat/demux.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/libavformat/demux.c b/libavformat/demux.c
index ecd4f40da9..d74d51e169 100644
--- a/libavformat/demux.c
+++ b/libavformat/demux.c
@@ -2078,8 +2078,8 @@ static int has_codec_parameters(const AVStream *st, const char **errmsg_ptr)
 static int try_decode_frame(AVFormatContext *s, AVStream *st,
                             const AVPacket *pkt, AVDictionary **options)
 {
-    FFStream *const sti = ffstream(st);
-    AVCodecContext *const avctx = sti->avctx;
+    FFStream *sti = ffstream(st);
+    AVCodecContext *avctx = sti->avctx;
     const AVCodec *codec;
     int got_picture = 1, ret = 0;
     AVFrame *frame = av_frame_alloc();
@@ -2104,6 +2104,12 @@ static int try_decode_frame(AVFormatContext *s, AVStream *st,
             goto fail;
         }
 
+        if (avctx && avctx->codec != codec) {
+          avcodec_free_context(&avctx);
+          avctx = avcodec_alloc_context3(codec);
+          sti->avctx = avctx;
+        }
+
         /* Force thread count to 1 since the H.264 decoder will not extract
          * SPS and PPS to extradata during multi-threaded decoding. */
         av_dict_set(options ? options : &thread_opt, "threads", "1", 0);
-- 
2.43.0