check the validity of the amount of the remaining bytes in the bitsteam before memcpy

Originally committed as revision 6105 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2006-08-27 07:19:11 +00:00
parent 716d73b47d
commit 39b434c6ae

View File

@ -2522,7 +2522,10 @@ static int mp_decode_frame(MPADecodeContext *s,
align_get_bits(&s->gb);
assert((get_bits_count(&s->gb) & 7) == 0);
s->last_buf_size= (s->gb.size_in_bits - get_bits_count(&s->gb))>>3;
memcpy(s->last_buf, s->gb.buffer + (get_bits_count(&s->gb)>>3), s->last_buf_size);
if(s->last_buf_size <0 || s->last_buf_size > BACKSTEP_SIZE || nb_frames<0)
s->last_buf_size= FFMIN(BACKSTEP_SIZE, buf_size - HEADER_SIZE);
assert(s->last_buf_size <= buf_size - HEADER_SIZE);
memcpy(s->last_buf, s->gb.buffer + buf_size - HEADER_SIZE - s->last_buf_size, s->last_buf_size);
break;
}