selinux: add a skb_owned_by() hook

Commit 90ba9b1986 (tcp: tcp_make_synack() can use alloc_skb())
broke certain SELinux/NetLabel configurations by no longer correctly
assigning the sock to the outgoing SYNACK packet.

Cost of atomic operations on the LISTEN socket is quite big,
and we would like it to happen only if really needed.

This patch introduces a new security_ops->skb_owned_by() method,
that is a void operation unless selinux is active.

Reported-by: Miroslav Vadkerti <mvadkert@redhat.com>
Diagnosed-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-security-module@vger.kernel.org
Acked-by: James Morris <james.l.morris@oracle.com>
Tested-by: Paul Moore <pmoore@redhat.com>
Acked-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet
2013-04-08 17:58:11 +00:00
committed by David S. Miller
parent c802d75962
commit ca10b9e9a8
5 changed files with 27 additions and 0 deletions

View File

@@ -737,6 +737,11 @@ static int cap_tun_dev_open(void *security)
{
return 0;
}
static void cap_skb_owned_by(struct sk_buff *skb, struct sock *sk)
{
}
#endif /* CONFIG_SECURITY_NETWORK */
#ifdef CONFIG_SECURITY_NETWORK_XFRM
@@ -1071,6 +1076,7 @@ void __init security_fixup_ops(struct security_operations *ops)
set_to_cap_if_null(ops, tun_dev_open);
set_to_cap_if_null(ops, tun_dev_attach_queue);
set_to_cap_if_null(ops, tun_dev_attach);
set_to_cap_if_null(ops, skb_owned_by);
#endif /* CONFIG_SECURITY_NETWORK */
#ifdef CONFIG_SECURITY_NETWORK_XFRM
set_to_cap_if_null(ops, xfrm_policy_alloc_security);