netfilter: xt_socket: fix broken v0 support

commit 681f130f39 ("netfilter: xt_socket: add XT_SOCKET_NOWILDCARD
flag") added a potential NULL dereference if an old iptables package
uses v0 of the match.

Fix this by removing the test on @info in fast path.

IPv6 can remove the test as well, as it uses v1 or v2.

Reported-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Eric Dumazet 2013-07-11 19:22:19 -07:00 committed by Pablo Neira Ayuso
parent f09eca8db0
commit baf60efa58

View File

@ -172,7 +172,7 @@ socket_match(const struct sk_buff *skb, struct xt_action_param *par,
/* Ignore non-transparent sockets,
if XT_SOCKET_TRANSPARENT is used */
if (info && info->flags & XT_SOCKET_TRANSPARENT)
if (info->flags & XT_SOCKET_TRANSPARENT)
transparent = ((sk->sk_state != TCP_TIME_WAIT &&
inet_sk(sk)->transparent) ||
(sk->sk_state == TCP_TIME_WAIT &&
@ -196,7 +196,11 @@ socket_match(const struct sk_buff *skb, struct xt_action_param *par,
static bool
socket_mt4_v0(const struct sk_buff *skb, struct xt_action_param *par)
{
return socket_match(skb, par, NULL);
static struct xt_socket_mtinfo1 xt_info_v0 = {
.flags = 0,
};
return socket_match(skb, par, &xt_info_v0);
}
static bool
@ -314,7 +318,7 @@ socket_mt6_v1_v2(const struct sk_buff *skb, struct xt_action_param *par)
/* Ignore non-transparent sockets,
if XT_SOCKET_TRANSPARENT is used */
if (info && info->flags & XT_SOCKET_TRANSPARENT)
if (info->flags & XT_SOCKET_TRANSPARENT)
transparent = ((sk->sk_state != TCP_TIME_WAIT &&
inet_sk(sk)->transparent) ||
(sk->sk_state == TCP_TIME_WAIT &&