[FFmpeg-cvslog] avcodec/mjpegdec: Check for unsupported bayer case

[Michael Niedermayer]

ffmpeg | branch: release/4.3 | Michael Niedermayer <michael at niedermayer.cc> | Sun Sep 18 23:42:02 2022 +0200| [37ac298e096002a0e0e240cdcad5c64a60870cba] | committer: Michael Niedermayer

avcodec/mjpegdec: Check for unsupported bayer case

Fixes: out of array access
Fixes: 51462/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_TIFF_fuzzer-662559341582745

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 dd81cc22b3dd5bd6badf012b4fe4c19e062650f4)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=37ac298e096002a0e0e240cdcad5c64a60870cba
---

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

diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index 94dae34bd0..bcb1d4ea77 100644
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -1199,6 +1199,8 @@ static int ljpeg_decode_rgb_scan(MJpegDecodeContext *s, int nb_components, int p
                 ptr[3*mb_x + 2] = buffer[mb_x][2] + ptr[3*mb_x + 1];
             }
         } else if (s->bayer) {
+            if (s->bits <= 8)
+                return AVERROR_PATCHWELCOME;
             if (nb_components == 1) {
                 /* Leave decoding to the TIFF/DNG decoder (see comment in ff_mjpeg_decode_sof) */
                 for (mb_x = 0; mb_x < width; mb_x++)