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

Kuniyuki Iwashima
2023-10-30T20:11:34Z

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