[FFmpeg-cvslog] avcodec/mjpegdec: Restore non bayer checks in ljpeg_decode_rgb_scan()

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Thu Sep 12 21:13:11 2019 +0200| [3b5ce76b1a68430f07645eaebe77946116977dbb] | committer: Michael Niedermayer

avcodec/mjpegdec: Restore non bayer checks in ljpeg_decode_rgb_scan()

Fixes: out of array write
Fixes: 17088/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_JPEGLS_fuzzer-5654877765632000

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

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=3b5ce76b1a68430f07645eaebe77946116977dbb
---

 libavcodec/mjpegdec.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index 5a80b7d289..f095afaed8 100644
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -1071,6 +1071,10 @@ static int ljpeg_decode_rgb_scan(MJpegDecodeContext *s, int nb_components, int p
     int resync_mb_x = 0;
     int vpred[6];
 
+    if (!s->bayer && s->nb_components < 3)
+        return AVERROR_INVALIDDATA;
+    if (s->bayer && s->nb_components > 2)
+        return AVERROR_INVALIDDATA;
     if (s->nb_components <= 0 || s->nb_components > 4)
         return AVERROR_INVALIDDATA;
     if (s->v_max != 1 || s->h_max != 1 || !s->lossless)