[FFmpeg-cvslog] avcodec/msvideo1: Check for too small dimensions

[Michael Niedermayer]

ffmpeg | branch: release/4.1 | Michael Niedermayer <michael at niedermayer.cc> | Sat Dec  1 22:16:19 2018 +0100| [558ba71de5c75bd7d2cced51361180baaf32cfd7] | committer: Michael Niedermayer

avcodec/msvideo1: Check for too small dimensions

Such low resolution would result in empty output as a minimum of 4x4 is needed
We could also check for multiple of 4 dimensions but that is not needed

Fixes: Timeout
Fixes: 11191/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MSVIDEO1_fuzzer-5739529588178944

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 953bd58861ad933e614510140b05a61e3d1375be)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=558ba71de5c75bd7d2cced51361180baaf32cfd7
---

 libavcodec/msvideo1.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libavcodec/msvideo1.c b/libavcodec/msvideo1.c
index 29700f54b6..de048d8b6f 100644
--- a/libavcodec/msvideo1.c
+++ b/libavcodec/msvideo1.c
@@ -62,6 +62,9 @@ static av_cold int msvideo1_decode_init(AVCodecContext *avctx)
 
     s->avctx = avctx;
 
+    if (avctx->width < 4 || avctx->height < 4)
+        return AVERROR_INVALIDDATA;
+
     /* figure out the colorspace based on the presence of a palette */
     if (s->avctx->bits_per_coded_sample == 8) {
         s->mode_8bit = 1;