avcodec/mpegvideo_enc: Do not duplicate pictures on shifting

Fixes: out of array access
Fixes: 69098/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MPEG2VIDEO_fuzzer-6107989688778752
Fixes: 69599/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MPEG4_fuzzer-4848626296225792.fuzz

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 9c8881cb35)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Michael Niedermayer 2024-06-20 00:44:08 +02:00
parent 35be459c27
commit 0e2bff1a88
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@ -1297,6 +1297,8 @@ static int load_input_picture(MpegEncContext *s, const AVFrame *pic_arg)
/* shift buffer entries */
for (i = flush_offset; i < MAX_PICTURE_COUNT /*s->encoding_delay + 1*/; i++)
s->input_picture[i - flush_offset] = s->input_picture[i];
for (int i = MAX_B_FRAMES + 1 - flush_offset; i <= MAX_B_FRAMES; i++)
s->input_picture[i] = NULL;
s->input_picture[encoding_delay] = (Picture*) pic;