[FFmpeg-cvslog] avcodec/iff: Check that video_size is large enough for the read parameters

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sat Nov 30 12:22:25 2019 +0100| [f1b97f62f86d5dca35d01d7a5ebbc5dca2a88ae6] | committer: Michael Niedermayer

avcodec/iff: Check that video_size is large enough for the read parameters

video is allocated before parameters like bpp are read.

Fixes: out of array access
Fixes: 19084/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_IFF_ILBM_fuzzer-5718556033679360
Fixes: 19465/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_IFF_ILBM_fuzzer-5759908398235648

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=f1b97f62f86d5dca35d01d7a5ebbc5dca2a88ae6
---

 libavcodec/iff.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/libavcodec/iff.c b/libavcodec/iff.c
index 267b09b6af..f82141d2e7 100644
--- a/libavcodec/iff.c
+++ b/libavcodec/iff.c
@@ -322,6 +322,8 @@ static int extract_header(AVCodecContext *const avctx,
             av_log(avctx, AV_LOG_ERROR, "Invalid number of bitplanes: %u\n", s->bpp);
             return AVERROR_INVALIDDATA;
         }
+        if (s->video_size && s->planesize * s->bpp * avctx->height > s->video_size)
+            return AVERROR_INVALIDDATA;
 
         av_freep(&s->ham_buf);
         av_freep(&s->ham_palbuf);