avformat/mov: Fix signed integer overflows with total_size
authorVitaly Buka <vitalybuka-at-google.com@ffmpeg.org>
Sun, 20 Aug 2017 18:56:47 +0000 (11:56 -0700)
committerMichael Niedermayer <michael@niedermayer.cc>
Thu, 24 Aug 2017 10:03:52 +0000 (12:03 +0200)
Signed integer overflow is undefined behavior.
Detected with clang and -fsanitize=signed-integer-overflow

Signed-off-by: Vitaly Buka <vitalybuka@google.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit 4a404cb5b90b878cbe1bb528fac65cf508668cc5)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
libavformat/mov.c

index 017df0f..478b50b 100644 (file)
@@ -3979,7 +3979,7 @@ static int mov_read_default(MOVContext *c, AVIOContext *pb, MOVAtom atom)
 
     if (atom.size < 0)
         atom.size = INT64_MAX;
-    while (total_size + 8 <= atom.size && !avio_feof(pb)) {
+    while (total_size <= atom.size - 8 && !avio_feof(pb)) {
         int (*parse)(MOVContext*, AVIOContext*, MOVAtom) = NULL;
         a.size = atom.size;
         a.type=0;