pgssubdec: Check RLE size before copying

Make sure the buffer size does not exceed the expected
RLE size.

Prevent an out of array bound write.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Bug-Id: CVE-2013-0852

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
(cherry picked from commit d98e6c5d5d)
Signed-off-by: Diego Biurrun <diego@biurrun.de>
This commit is contained in:
Michael Niedermayer
2014-07-30 21:31:19 -04:00
committed by Diego Biurrun
parent d396987c30
commit a1f7844a11

View File

@@ -196,6 +196,13 @@ static int parse_picture_segment(AVCodecContext *avctx,
/* Decode rle bitmap length, stored size includes width/height data */ /* Decode rle bitmap length, stored size includes width/height data */
rle_bitmap_len = bytestream_get_be24(&buf) - 2*2; rle_bitmap_len = bytestream_get_be24(&buf) - 2*2;
if (buf_size > rle_bitmap_len) {
av_log(avctx, AV_LOG_ERROR,
"Buffer dimension %d larger than the expected RLE data %d\n",
buf_size, rle_bitmap_len);
return AVERROR_INVALIDDATA;
}
/* Get bitmap dimensions from data */ /* Get bitmap dimensions from data */
width = bytestream_get_be16(&buf); width = bytestream_get_be16(&buf);
height = bytestream_get_be16(&buf); height = bytestream_get_be16(&buf);