[FFmpeg-cvslog] avformat/img2dec: Clear padding data after EOF

[Michael Niedermayer]

ffmpeg | branch: release/4.2 | Michael Niedermayer <michael at niedermayer.cc> | Sun Aug  4 22:00:35 2024 +0200| [e9cf7a8c81d525b743d0a4344e927ab51a888d47] | committer: Michael Niedermayer

avformat/img2dec: Clear padding data after EOF

Fixes: use-of-uninitialized-value
Fixes: 70852/clusterfuzz-testcase-minimized-ffmpeg_IO_DEMUXER_fuzzer-5179190066872320

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Kacper Michajlow <kasper93 at gmail.com>
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 3978e81809a3daf278199849f7bbeacbffb9fa09)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=e9cf7a8c81d525b743d0a4344e927ab51a888d47
---

 libavformat/img2dec.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libavformat/img2dec.c b/libavformat/img2dec.c
index 1108fa0945..7d60d332b3 100644
--- a/libavformat/img2dec.c
+++ b/libavformat/img2dec.c
@@ -518,6 +518,7 @@ int ff_img_read_packet(AVFormatContext *s1, AVPacket *pkt)
         }
         goto fail;
     } else {
+        memset(pkt->data + pkt->size, 0, AV_INPUT_BUFFER_PADDING_SIZE);
         s->img_count++;
         s->img_number++;
         s->pts++;