[FFmpeg-cvslog] avcodec/g2meet: Check RGB upper limit

[Michael Niedermayer]

ffmpeg | branch: release/2.8 | Michael Niedermayer <michael at niedermayer.cc> | Fri Apr 27 20:16:13 2018 +0200| [fc097bf1cd0af7bbab09e2f1af4ae39eb0ca4eea] | committer: Michael Niedermayer

avcodec/g2meet: Check RGB upper limit

Fixes: runtime error: left shift of 1876744317 by 16 places cannot be represented in type 'int'
Fixes: 6799/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_G2M_fuzzer-5115274731716608

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 4dd2c8b9ea46b4e008a8bfc2077834428cd5a17c)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=fc097bf1cd0af7bbab09e2f1af4ae39eb0ca4eea
---

 libavcodec/g2meet.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libavcodec/g2meet.c b/libavcodec/g2meet.c
index 14dd05babc..fed35a271b 100644
--- a/libavcodec/g2meet.c
+++ b/libavcodec/g2meet.c
@@ -555,7 +555,7 @@ static uint32_t epic_decode_pixel_pred(ePICContext *dc, int x, int y,
         B     = ((pred >> B_shift) & 0xFF) - TOSIGNED(delta);
     }
 
-    if (R<0 || G<0 || B<0) {
+    if (R<0 || G<0 || B<0 || R > 255 || G > 255 || B > 255) {
         av_log(NULL, AV_LOG_ERROR, "RGB %d %d %d is out of range\n", R, G, B);
         return 0;
     }