[FFmpeg-cvslog] avcodec/sunrast: Use ptrdiff_t for stride

[Andreas Rheinhardt]

ffmpeg | branch: master | Andreas Rheinhardt <andreas.rheinhardt at outlook.com> | Thu Sep 29 13:18:54 2022 +0200| [02c19dfb8552cb40b02ff9c8d8d3c5e12d5c71e1] | committer: Andreas Rheinhardt

avcodec/sunrast: Use ptrdiff_t for stride

Fixes segfaults with negative linesizes; in particular,
this affected the sunraster-(1|8|24)bit-(raw|rle) and
sunraster-8bit_gray-raw FATE tests.

Reviewed-by: James Almer <jamrial at gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=02c19dfb8552cb40b02ff9c8d8d3c5e12d5c71e1
---

 libavcodec/sunrast.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/libavcodec/sunrast.c b/libavcodec/sunrast.c
index 77feef06e1..45b29e4d72 100644
--- a/libavcodec/sunrast.c
+++ b/libavcodec/sunrast.c
@@ -31,7 +31,8 @@ static int sunrast_decode_frame(AVCodecContext *avctx, AVFrame *p,
 {
     const uint8_t *buf       = avpkt->data;
     const uint8_t *buf_end   = avpkt->data + avpkt->size;
-    unsigned int w, h, depth, type, maptype, maplength, stride, x, y, len, alen;
+    unsigned int w, h, depth, type, maptype, maplength, x, y, len, alen;
+    ptrdiff_t stride;
     uint8_t *ptr, *ptr2 = NULL;
     const uint8_t *bufstart = buf;
     int ret;
@@ -141,7 +142,7 @@ static int sunrast_decode_frame(AVCodecContext *avctx, AVFrame *p,
 
     if (type == RT_BYTE_ENCODED) {
         int value, run;
-        uint8_t *end = ptr + h * stride;
+        uint8_t *end = ptr + (ptrdiff_t)h * stride;
 
         x = 0;
         while (ptr != end && buf < buf_end) {