net/unix: don't show information about sockets from other namespaces
socket_diag shows information only about sockets from a namespace where
a diag socket lives.
But if we request information about one unix socket, the kernel don't
check that its netns is matched with a diag socket namespace, so any
user can get information about any unix socket in a system. This looks
like a bug.
v2: add a Fixes tag
Fixes: 51d7cccf0723 ("net: make sock diag per-namespace")
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/unix/diag.c b/net/unix/diag.c
index 4d96797..384c84e 100644
--- a/net/unix/diag.c
+++ b/net/unix/diag.c
@@ -257,6 +257,8 @@ static int unix_diag_get_exact(struct sk_buff *in_skb,
err = -ENOENT;
if (sk == NULL)
goto out_nosk;
+ if (!net_eq(sock_net(sk), net))
+ goto out;
err = sock_diag_check_cookie(sk, req->udiag_cookie);
if (err)
