[PATCH v1 net 1/2] dccp: Call security_inet_conn_request() after setting IPv4 addresses.

[Kuniyuki Iwashima <kuniyu@amazon.com>]

Initially, commit 4237c75c0a35 ("[MLSXFRM]: Auto-labeling of child
sockets") introduced security_inet_conn_request() in some functions
where reqsk is allocated.  The hook is added just after the allocation,
so reqsk's IPv4 remote address was not initialised then.

However, SELinux/Smack started to read it in netlbl_req_setattr()
after the cited commits.

This bug was partially fixed by commit 284904aa7946 ("lsm: Relocate
the IPv4 security_inet_conn_request() hooks").

This patch fixes the last bug in DCCPv4.

Fixes: 389fb800ac8b ("netlabel: Label incoming TCP connections correctly in SELinux")
Fixes: 07feee8f812f ("netlabel: Cleanup the Smack/NetLabel code to fix incoming TCP connections")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
---
Cc: James Morris <jmorris@namei.org>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: Paul Moore <paul.moore@hp.com>
---
 net/dccp/ipv4.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index 1b8cbfda6e5d..44b033fe1ef6 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -629,9 +629,6 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 	if (dccp_parse_options(sk, dreq, skb))
 		goto drop_and_free;
 
-	if (security_inet_conn_request(sk, skb, req))
-		goto drop_and_free;
-
 	ireq = inet_rsk(req);
 	sk_rcv_saddr_set(req_to_sk(req), ip_hdr(skb)->daddr);
 	sk_daddr_set(req_to_sk(req), ip_hdr(skb)->saddr);
@@ -639,6 +636,9 @@ int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
 	ireq->ireq_family = AF_INET;
 	ireq->ir_iif = READ_ONCE(sk->sk_bound_dev_if);
 
+	if (security_inet_conn_request(sk, skb, req))
+		goto drop_and_free;
+
 	/*
 	 * Step 3: Process LISTEN state
 	 *
-- 
2.30.2