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 4d9679701a6df5113df3e24a1c9b86e2a63b3710..384c84e83462e51d24e469515f4b52f8dcf55877 100644 (file)
--- 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)