From 7bc2176c4d7eeea1062604d641d51639cf009778 Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Wed, 7 Oct 2020 23:22:59 +0200 Subject: [PATCH] avcodec/h264_slice: fix undefined integer overflow with POC in error concealment Alternatively the POC could be changed to 64bit. the large values seem to be within what is allowed. Fixes: signed integer overflow: 2147483646 + 2 cannot be represented in type 'int' Fixes: 26076/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_H264_fuzzer-5711127201447936 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer (cherry picked from commit 182d7a74276ea70aec6d3d7bd9a1da3d327358f2) Signed-off-by: Michael Niedermayer --- libavcodec/h264_slice.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libavcodec/h264_slice.c b/libavcodec/h264_slice.c index 713953778a..4e3abf859b 100644 --- a/libavcodec/h264_slice.c +++ b/libavcodec/h264_slice.c @@ -1599,7 +1599,7 @@ static int h264_field_start(H264Context *h, const H264SliceContext *sl, prev->f->format, prev->f->width, prev->f->height); - h->short_ref[0]->poc = prev->poc + 2; + h->short_ref[0]->poc = prev->poc + 2U; } else if (!h->frame_recovered && !h->avctx->hwaccel) ff_color_frame(h->short_ref[0]->f, c); h->short_ref[0]->frame_num = h->poc.prev_frame_num;