[FFmpeg-cvslog] avcodec/h264dec: Skip late SEI

[Michael Niedermayer]

ffmpeg | branch: release/4.1 | Michael Niedermayer <michael at niedermayer.cc> | Wed Apr 27 22:16:51 2022 +0200| [99f1f07b78c7a73f1e1eea5678b88c2b9d5bac3a] | committer: Michael Niedermayer

avcodec/h264dec: Skip late SEI

Fixes: Race condition
Fixes: clusterfuzz-testcase-minimized-mediasource_MP2T_AVC_pipeline_integration_fuzzer-6282675434094592

Found-by: google ClusterFuzz
Tested-by: Dan Sanders <sandersd at google.com>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit f7dd408d64013ae177c1f8d0e04418e5075db5bc)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=99f1f07b78c7a73f1e1eea5678b88c2b9d5bac3a
---

 libavcodec/h264dec.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libavcodec/h264dec.c b/libavcodec/h264dec.c
index 0e189da61a..dc259ceff2 100644
--- a/libavcodec/h264dec.c
+++ b/libavcodec/h264dec.c
@@ -699,6 +699,10 @@ static int decode_nal_units(H264Context *h, const uint8_t *buf, int buf_size)
             avpriv_request_sample(avctx, "data partitioning");
             break;
         case H264_NAL_SEI:
+            if (h->setup_finished) {
+                avpriv_request_sample(avctx, "Late SEI");
+                break;
+            }
             ret = ff_h264_sei_decode(&h->sei, &nal->gb, &h->ps, avctx);
             h->has_recovery_point = h->has_recovery_point || h->sei.recovery_point.recovery_frame_cnt != -1;
             if (avctx->debug & FF_DEBUG_GREEN_MD)