Force gif aspect ratio multiplication to 64bit.

Avoids a possible integer overflow.
11 years ago · 87f2999641
parent b6850e132f
commit 87f2999641
1 changed files with 3 additions and 2 deletions
--- a/libavformat/gif.c
+++ b/libavformat/gif.c
@ -33,10 +33,11 @@ static int gif_image_write_header(AVFormatContext *s, int width, int height,
 {
    AVIOContext *pb = s->pb;
    AVRational sar = s->streams[0]->codec->sample_aspect_ratio;
-    int i, aspect = 0;
+    int i;
+    int64_t aspect = 0;

    if (sar.num > 0 && sar.den > 0) {
-        aspect = sar.num * 64 / sar.den - 15;
+        aspect = sar.num * 64LL / sar.den - 15;
        if (aspect < 0 || aspect > 255)
            aspect = 0;
    }