[FFmpeg-devel] [PATCH 1/2] avcodec/wcmv: Fix integer overflows

Michael Niedermayer michael at niedermayer.cc
Tue Sep 25 04:56:40 EEST 2018


Fixes: signed integer overflow: 262140 * 65535 cannot be represented in type 'int'
Fixes: 10090/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WCMV_fuzzer-5691269368512512

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
---
 libavcodec/wcmv.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libavcodec/wcmv.c b/libavcodec/wcmv.c
index 384ceecd32..ebd5ef66f4 100644
--- a/libavcodec/wcmv.c
+++ b/libavcodec/wcmv.c
@@ -113,6 +113,8 @@ static int decode_frame(AVCodecContext *avctx,
             bytestream2_skip(&bgb, 4);
             w = bytestream2_get_le16(&bgb);
             h = bytestream2_get_le16(&bgb);
+            if (x + bpp * (int64_t)w * h > INT_MAX)
+                return AVERROR_INVALIDDATA;
             x += bpp * w * h;
         }
 
@@ -140,6 +142,8 @@ static int decode_frame(AVCodecContext *avctx,
             bytestream2_skip(&gb, 4);
             w = bytestream2_get_le16(&gb);
             h = bytestream2_get_le16(&gb);
+            if (x + bpp * (int64_t)w * h > INT_MAX)
+                return AVERROR_INVALIDDATA;
             x += bpp * w * h;
         }
 
-- 
2.19.0



More information about the ffmpeg-devel mailing list