Subject: [PATCH 17/25] net/unix: don't show information about sockets from other namespaces

From: Andrei Vagin <[email-masked]>
Date: Wed, 25 Oct 2017 10:16:42 -0700

[ Upstream commit 0f5da659d8f1810f44de14acf2c80cd6499623a0 ]

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 <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 net/unix/diag.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/unix/diag.c b/net/unix/diag.c
index 4d9679701a6d..384c84e83462 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)
-- 
2.13.6