jvdec: avoid unsigned overflow in comparison

The return type of strlen is size_t, i.e. unsigned, so if pd->buf_size
is 3, the right side overflows leading to a wrong result of the
comparison and subsequently a heap buffer overflow.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
(cherry picked from commit db374790c7)

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Andreas Cadhalpun 2015-11-06 21:04:34 +01:00 committed by Michael Niedermayer
parent 9f6e755272
commit bbeae2c690
1 changed files with 1 additions and 1 deletions

View File

@ -54,7 +54,7 @@ typedef struct JVDemuxContext {
static int read_probe(AVProbeData *pd)
{
if (pd->buf[0] == 'J' && pd->buf[1] == 'V' && strlen(MAGIC) <= pd->buf_size - 4 &&
if (pd->buf[0] == 'J' && pd->buf[1] == 'V' && strlen(MAGIC) + 4 <= pd->buf_size &&
!memcmp(pd->buf + 4, MAGIC, strlen(MAGIC)))
return AVPROBE_SCORE_MAX;
return 0;