libavformat/mtv: Check for min header size first

Abort immediately if we are not getting enough
data to extract the required fields.

Signed-off-by: Reynaldo H. Verdejo Pinochet <r.verdejo@sisa.samsung.com>
This commit is contained in:
Reynaldo H. Verdejo Pinochet 2014-01-23 15:43:07 -03:00
parent bf23642dcc
commit 30f4c58f6f

View File

@ -52,12 +52,18 @@ typedef struct MTVDemuxContext {
static int mtv_probe(AVProbeData *p)
{
/* we need at least 57 bytes from the header
* to try parsing all required fields
*/
if (p->buf_size < 57)
return 0;
/* Magic is 'AMV' */
if (*p->buf != 'A' || *(p->buf + 1) != 'M' || *(p->buf + 2) != 'V')
return 0;
/* Check for nonzero in bpp and (width|height) header fields */
if(p->buf_size < 57 || !(p->buf[51] && AV_RL16(&p->buf[52]) | AV_RL16(&p->buf[54])))
if(!(p->buf[51] && AV_RL16(&p->buf[52]) | AV_RL16(&p->buf[54])))
return 0;
/* If width or height are 0 then imagesize header field should not */