commit
a3c18422a4b4e108bcf6a2328f48867e1003fd95 upstream.
Socket must be held while under the protection of the l2tp lock; there
is no guarantee that sk remains valid after the read_unlock_bh() call.
Same issue for l2tp_ip and l2tp_ip6.
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
[bwh: Backported to 3.2:
- Drop changes in l2tp_ip6.c
- Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
read_lock_bh(&l2tp_ip_lock);
sk = __l2tp_ip_bind_lookup(&init_net, iph->daddr, 0, tunnel_id);
+ if (!sk) {
+ read_unlock_bh(&l2tp_ip_lock);
+ goto discard;
+ }
+
+ sock_hold(sk);
read_unlock_bh(&l2tp_ip_lock);
}
- if (sk == NULL)
- goto discard;
-
- sock_hold(sk);
-
if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
goto discard_put;