lavf: avoid integer overflow when estimating bitrate

Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind CC: libav-stable@libav.org
12 years ago · df33a58e53
parent fab694dd39
commit df33a58e53
1 changed files with 7 additions and 2 deletions
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@ -1757,8 +1757,13 @@ static void estimate_timings_from_bit_rate(AVFormatContext *ic)
        int bit_rate = 0;
        for(i=0;i<ic->nb_streams;i++) {
            st = ic->streams[i];
-            if (st->codec->bit_rate > 0)
-            bit_rate += st->codec->bit_rate;
+            if (st->codec->bit_rate > 0) {
+                if (INT_MAX - st->codec->bit_rate > bit_rate) {
+                    bit_rate = 0;
+                    break;
+                }
+                bit_rate += st->codec->bit_rate;
+            }
        }
        ic->bit_rate = bit_rate;
    }