From: Richard Alpe <richard.alpe@ericsson.com>
Date: Mon, 16 May 2016 09:14:54 +0000 (+0200)
Subject: tipc: check nl sock before parsing nested attributes
X-Git-Tag: firefly_0821_release~176^2~4^2~40^2~79
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=23cdd8c3cbe9d790f23d7f9ae14e9b828f56f69c;p=firefly-linux-kernel-4.4.55.git

tipc: check nl sock before parsing nested attributes

[ Upstream commit 45e093ae2830cd1264677d47ff9a95a71f5d9f9c ]

Make sure the socket for which the user is listing publication exists
before parsing the socket netlink attributes.

Prior to this patch a call without any socket caused a NULL pointer
dereference in tipc_nl_publ_dump().

Tested-and-reported-by: Baozeng Ding <sploving1@gmail.com>
Signed-off-by: Richard Alpe <richard.alpe@ericsson.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.cm>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index e53003cf7703..9b713e0ce00d 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -2814,6 +2814,9 @@ int tipc_nl_publ_dump(struct sk_buff *skb, struct netlink_callback *cb)
 		if (err)
 			return err;
 
+		if (!attrs[TIPC_NLA_SOCK])
+			return -EINVAL;
+
 		err = nla_parse_nested(sock, TIPC_NLA_SOCK_MAX,
 				       attrs[TIPC_NLA_SOCK],
 				       tipc_nl_sock_policy);