[FFmpeg-cvslog] avcodec/mpegvideo_dec: Fix UB NULL + 0

[Andreas Rheinhardt]

ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at outlook.com> | Wed Sep 28 20:04:54 2022 +0200| [04196852a2761b6e1d751570ef31d3a6495fd8bd] | committer: Andreas Rheinhardt

avcodec/mpegvideo_dec: Fix UB NULL + 0

Affected the mpeg2-field-enc FATE-test.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=04196852a2761b6e1d751570ef31d3a6495fd8bd
---

 libavcodec/mpegvideo_dec.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libavcodec/mpegvideo_dec.c b/libavcodec/mpegvideo_dec.c
index 5b37e79e36..6d1edc027a 100644
--- a/libavcodec/mpegvideo_dec.c
+++ b/libavcodec/mpegvideo_dec.c
@@ -446,8 +446,8 @@ int ff_mpv_frame_start(MpegEncContext *s, AVCodecContext *avctx)
     if (s->picture_structure != PICT_FRAME) {
         for (int i = 0; i < 4; i++) {
             if (s->picture_structure == PICT_BOTTOM_FIELD) {
-                s->current_picture.f->data[i] +=
-                    s->current_picture.f->linesize[i];
+                s->current_picture.f->data[i] = FF_PTR_ADD(s->current_picture.f->data[i],
+                                                           s->current_picture.f->linesize[i]);
             }
             s->current_picture.f->linesize[i] *= 2;
             s->last_picture.f->linesize[i]    *= 2;