[FFmpeg-cvslog] avcodec/hevcdec: decode at most one slice reporting being the first in the picture

[James Almer]

ffmpeg | branch: master | James Almer <jamrial at gmail.com> | Mon Mar 18 17:25:58 2019 -0300| [70c8c8a818f39bc262565ec29fae2baffb3e1660] | committer: James Almer

avcodec/hevcdec: decode at most one slice reporting being the first in the picture

Fixes deadlocks when decoding packets containing more than one of the aforementioned
slices when using frame threads.

Tested-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>
Signed-off-by: James Almer <jamrial at gmail.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=70c8c8a818f39bc262565ec29fae2baffb3e1660
---

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

diff --git a/libavcodec/hevcdec.c b/libavcodec/hevcdec.c
index 967f8f1def..86adab0ae1 100644
--- a/libavcodec/hevcdec.c
+++ b/libavcodec/hevcdec.c
@@ -2927,6 +2927,10 @@ static int decode_nal_unit(HEVCContext *s, const H2645NAL *nal)
         }
 
         if (s->sh.first_slice_in_pic_flag) {
+            if (s->ref) {
+                av_log(s->avctx, AV_LOG_ERROR, "Two slices reporting being the first in the same frame.\n");
+                goto fail;
+            }
             if (s->max_ra == INT_MAX) {
                 if (s->nal_unit_type == HEVC_NAL_CRA_NUT || IS_BLA(s)) {
                     s->max_ra = s->poc;