The check `start + res < start' is broken since pointer overflow is
undefined behavior in C. Many compilers such as gcc/clang optimize
away this check.
Use `res > end - start' instead. Also change `res' to unsigned int
to avoid signed left-shift overflow.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Martin Storsjö <martin@martin.st>
static const uint8_t *avc_mp4_find_startcode(const uint8_t *start, const uint8_t *end, int nal_length_size)
{
- int res = 0;
+ unsigned int res = 0;
if (end - start < nal_length_size)
return NULL;
while (nal_length_size--)
res = (res << 8) | *start++;
- if (start + res > end || res < 0 || start + res < start)
+ if (res > end - start)
return NULL;
return start + res;