Commit 24d87712 authored by Ariel Silver's avatar Ariel Silver Committed by Mauro Carvalho Chehab
Browse files

media: dvb-net: fix OOB access in ULE extension header tables 



The ule_mandatory_ext_handlers[] and ule_optional_ext_handlers[] tables
in handle_one_ule_extension() are declared with 255 elements (valid
indices 0-254), but the index htype is derived from network-controlled
data as (ule_sndu_type & 0x00FF), giving a range of 0-255. When
htype equals 255, an out-of-bounds read occurs on the function pointer
table, and the OOB value may be called as a function pointer.

Add a bounds check on htype against the array size before either table
is accessed. Out-of-range values now cause the SNDU to be discarded.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Reported-by: default avatarAriel Silver <arielsilver77@gmail.com>
Signed-off-by: default avatarAriel Silver <arielsilver77@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent 6de23f81

drivers/media/dvb-core/dvb_net.c

+3 −0
Original line number Diff line number Diff line
@@ -228,6 +228,9 @@ static int handle_one_ule_extension( struct dvb_net_priv *p ) 
	unsigned char hlen = (p->ule_sndu_type & 0x0700) >> 8;

	unsigned char htype = p->ule_sndu_type & 0x00FF;



	if (htype >= ARRAY_SIZE(ule_mandatory_ext_handlers))

		return -1;



	/* Discriminate mandatory and optional extension headers. */

	if (hlen == 0) {

		/* Mandatory extension header */