From 63e400a8807dca7b0ffa3841df2e31f7419abb8d Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michael@niedermayer.cc>
Date: Sun, 26 Feb 2017 20:28:00 +0100
Subject: [PATCH] avcodec/pictordec: Check plane value before doing value/mask
 computations

Fixes integer overflow
Fixes: 675/clusterfuzz-testcase-6722971232108544

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
---
 libavcodec/pictordec.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/pictordec.c b/libavcodec/pictordec.c
index a3d72e3f25..a09ee379c0 100644
--- a/libavcodec/pictordec.c
+++ b/libavcodec/pictordec.c
@@ -77,10 +77,10 @@ static void picmemset(PicContext *s, AVFrame *frame, int value, int run,
                 if (*y < 0) {
                    *y = s->height - 1;
                    *plane += 1;
-                   value <<= bits_per_plane;
-                   mask  <<= bits_per_plane;
                    if (*plane >= s->nb_planes)
                        return;
+                   value <<= bits_per_plane;
+                   mask  <<= bits_per_plane;
                 }
             }
         }