svq3: Avoid a division by zero

If the height is zero, the decompression will probably end up
failing due to not fitting into the allocated buffer later
anyway, so this doesn't need any more elaborate check.

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
Signed-off-by: Martin Storsjö <martin@martin.st>

diff --git a/libavcodec/svq3.c b/libavcodec/svq3.c
index 82fa6327129af072cfa5c60b9a2fd5d871dde810..a345788fb5aae31838bfe5b89b3e9ac3a0e0cc0b 100644 (file)
--- a/libavcodec/svq3.c
+++ b/libavcodec/svq3.c
@@ -980,7 +980,8 @@ static av_cold int svq3_decode_init(AVCodecContext *avctx)
             int offset                = get_bits_count(&gb) + 7 >> 3;
             uint8_t *buf;
 
-            if ((uint64_t)watermark_width * 4 > UINT_MAX / watermark_height)
+            if (watermark_height > 0 &&
+                (uint64_t)watermark_width * 4 > UINT_MAX / watermark_height)
                 return -1;
 
             buf = av_malloc(buf_len);