avcodec/mss2: Check for repeat overflow
authorMichael Niedermayer <michael@niedermayer.cc>
Sun, 10 Jan 2016 11:19:48 +0000 (12:19 +0100)
committerMichael Niedermayer <michael@niedermayer.cc>
Fri, 15 Jan 2016 16:39:04 +0000 (17:39 +0100)
Fixes: mss2_left_shift.wmv

Found-by: Piotr Bandurski <ami_stuff@o2.pl>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
(cherry picked from commit e273dade78943e22b71d0ddb67cd0d737fc26edf)

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
libavcodec/mss2.c

index 4d53f8a..ea448da 100644 (file)
@@ -209,8 +209,13 @@ static int decode_555(GetByteContext *gB, uint16_t *dst, int stride,
                     last_symbol = b << 8 | bytestream2_get_byte(gB);
                 else if (b > 129) {
                     repeat = 0;
-                    while (b-- > 130)
+                    while (b-- > 130) {
+                        if (repeat >= (INT_MAX >> 8) - 1) {
+                            av_log(NULL, AV_LOG_ERROR, "repeat overflow\n");
+                            return AVERROR_INVALIDDATA;
+                        }
                         repeat = (repeat << 8) + bytestream2_get_byte(gB) + 1;
+                    }
                     if (last_symbol == -2) {
                         int skip = FFMIN((unsigned)repeat, dst + w - p);
                         repeat -= skip;