[FFmpeg-cvslog] swscale/swscale_unscaled: don't add offsets to NULL pointers

[James Almer]

ffmpeg | branch: release/6.1 | James Almer <jamrial at gmail.com> | Sun Jul 13 19:50:57 2025 -0300| [e0b200a1b0164125afe05381ef41fc362475660a] | committer: Michael Niedermayer

swscale/swscale_unscaled: don't add offsets to NULL pointers

Fixes: libswscale/swscale_unscaled.c:916:20: runtime error: applying zero offset to null pointer
Signed-off-by: James Almer <jamrial at gmail.com>
(cherry picked from commit af9b43455a972841154b194057a79ee8b606e727)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=e0b200a1b0164125afe05381ef41fc362475660a
---

 libswscale/swscale_unscaled.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libswscale/swscale_unscaled.c b/libswscale/swscale_unscaled.c
index a5c9917799..95cc42d7e4 100644
--- a/libswscale/swscale_unscaled.c
+++ b/libswscale/swscale_unscaled.c
@@ -728,7 +728,7 @@ static int Rgb16ToPlanarRgb16Wrapper(SwsContext *c, const uint8_t *src[],
         return srcSliceH;
     }
 
-    for(i=0; i<4; i++) {
+    for (i = 0; i < 4 && dst[i]; i++) {
         dst2013[i] += stride2013[i] * srcSliceY / 2;
         dst1023[i] += stride1023[i] * srcSliceY / 2;
     }