From 45836a60f5b6326c7896a413e651aa35c8cc45dc Mon Sep 17 00:00:00 2001 From: Michael Niedermayer Date: Mon, 30 Sep 2019 08:02:11 +0200 Subject: [PATCH] avcodec/dxv: Check op_offset in dxv_decompress_yo() Fixes: signed integer overflow: -2147483648 - 8 cannot be represented in type 'int' Fixes: 17745/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_DXV_fuzzer-5734628463214592 Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Reviewed-by: Paul B Mahol Signed-off-by: Michael Niedermayer (cherry picked from commit 97450d2b6a08769cbc4665bc66f6db9e8c5da2a4) Signed-off-by: Michael Niedermayer --- libavcodec/dxv.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/libavcodec/dxv.c b/libavcodec/dxv.c index 03e8270463..c6866f18e6 100644 --- a/libavcodec/dxv.c +++ b/libavcodec/dxv.c @@ -797,6 +797,9 @@ static int dxv_decompress_yo(DXVContext *ctx, GetByteContext *gb, uint8_t *dst, *table0[256] = { 0 }, *table1[256] = { 0 }; int ret, state = 0, skip, oi = 0, v, vv; + if (op_offset < 8 || op_offset - 8 > bytestream2_get_bytes_left(gb)) + return AVERROR_INVALIDDATA; + dst = tex_data; bytestream2_skip(gb, op_offset - 8); if (op_size > max_op_size)