Commit 878ecb08 authored by Gavrilov Ilia's avatar Gavrilov Ilia Committed by David S. Miller
Browse files

ipv6: Fix out-of-bounds access in ipv6_find_tlv() 



optlen is fetched without checking whether there is more than one byte to parse.
It can lead to out-of-bounds access.

Found by InfoTeCS on behalf of Linux Verification Center
(linuxtesting.org) with SVACE.

Fixes: c61a4043 ("[IPV6]: Find option offset by type.")
Signed-off-by: default avatarGavrilov Ilia <Ilia.Gavrilov@infotecs.ru>
Reviewed-by: default avatarJiri Pirko <jiri@nvidia.com>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ba46c96d

net/ipv6/exthdrs_core.c

+2 −0
Original line number Diff line number Diff line
@@ -143,6 +143,8 @@ int ipv6_find_tlv(const struct sk_buff *skb, int offset, int type) 
			optlen = 1;

			break;

		default:

			if (len < 2)

				goto bad;

			optlen = nh[offset + 1] + 2;

			if (optlen > len)

				goto bad;