From e43669c77cb3a742b7d84ecdc7c68c4167a7709b Mon Sep 17 00:00:00 2001 From: Congyu Liu Date: Tue, 18 Jan 2022 14:20:13 -0500 Subject: net: fix information leakage in /proc/net/ptype commit 47934e06b65637c88a762d9c98329ae6e3238888 upstream. In one net namespace, after creating a packet socket without binding it to a device, users in other net namespaces can observe the new `packet_type` added by this packet socket by reading `/proc/net/ptype` file. This is minor information leakage as packet socket is namespace aware. Add a net pointer in `packet_type` to keep the net namespace of of corresponding packet socket. In `ptype_seq_show`, this net pointer must be checked when it is not NULL. Fixes: 2feb27dbe00c ("[NETNS]: Minor information leak via /proc/net/ptype file.") Signed-off-by: Congyu Liu Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- include/linux/netdevice.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index ce81cc96a98d..fba54624191a 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -2636,6 +2636,7 @@ struct packet_type { struct net_device *); bool (*id_match)(struct packet_type *ptype, struct sock *sk); + struct net *af_packet_net; void *af_packet_priv; struct list_head list; }; -- cgit v1.2.3