From 573987e8aac8a55515ef219bb76e68e3c90f367b Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Thu, 20 Jun 2024 00:44:08 +0200 Subject: [PATCH] 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 (cherry picked from commit 9c8881cb3534b257d6e6539f563006599cd96b48) Signed-off-by: Michael Niedermayer --- libavcodec/mpegvideo_enc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/libavcodec/mpegvideo_enc.c b/libavcodec/mpegvideo_enc.c index c4c174a02e..5fab302148 100644 --- a/libavcodec/mpegvideo_enc.c +++ b/libavcodec/mpegvideo_enc.c @@ -1252,6 +1252,8 @@ static int load_input_picture(MpegEncContext *s, const AVFrame *pic_arg) /* shift buffer entries */ for (int i = flush_offset; i <= MAX_B_FRAMES; 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] = pic;