[FFmpeg-cvslog] avcodec/pictordec: Only recalculate d when y changes in picmemset()

[Michael Niedermayer]

ffmpeg | branch: master | Michael Niedermayer <michael at niedermayer.cc> | Sat Apr 13 01:19:03 2019 +0200| [838710bd6c5f65d436408c0737b49628f23f9ca9] | committer: Michael Niedermayer

avcodec/pictordec: Only recalculate d when y changes in picmemset()

Fixes: Timeout (21->18sec)
Fixes: 14124/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PICTOR_fuzzer-5633887734071296

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=838710bd6c5f65d436408c0737b49628f23f9ca9
---

 libavcodec/pictordec.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libavcodec/pictordec.c b/libavcodec/pictordec.c
index af99c486b8..2e6fcdca52 100644
--- a/libavcodec/pictordec.c
+++ b/libavcodec/pictordec.c
@@ -68,10 +68,10 @@ static void picmemset(PicContext *s, AVFrame *frame, unsigned value, int run,
     int planel = *plane;
     value   <<= shift;
 
+    d = frame->data[0] + yl * frame->linesize[0];
     while (run > 0) {
         int j;
         for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) {
-            d = frame->data[0] + yl * frame->linesize[0];
             d[xl] |= (value >> j) & mask;
             xl += 1;
             if (xl == s->width) {
@@ -85,6 +85,7 @@ static void picmemset(PicContext *s, AVFrame *frame, unsigned value, int run,
                    value <<= bits_per_plane;
                    mask  <<= bits_per_plane;
                 }
+                d = frame->data[0] + yl * frame->linesize[0];
             }
         }
         run--;