[PATCH 4.9 078/109] gtp: fix cross netns recv on gtp socket

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Andreas Schultz <aschultz@xxxxxxxx>


[ Upstream commit 3ab1b469e847ba425af3c5ad5068cc94b55b38d0 ]

The use of the passed through netlink src_net to check for a
cross netns operation was wrong. Using the GTP socket and the
GTP netdevice is always correct (even if the netdev has been
moved to new netns after link creation).

Remove the now obsolete net field from gtp_dev.

Signed-off-by: Andreas Schultz <aschultz@xxxxxxxx>
Acked-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/net/gtp.c |   10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -69,7 +69,6 @@ struct gtp_dev {
 	struct socket		*sock0;
 	struct socket		*sock1u;
 
-	struct net		*net;
 	struct net_device	*dev;
 
 	unsigned int		hash_size;
@@ -316,7 +315,7 @@ static int gtp_encap_recv(struct sock *s
 
 	netdev_dbg(gtp->dev, "encap_recv sk=%p\n", sk);
 
-	xnet = !net_eq(gtp->net, dev_net(gtp->dev));
+	xnet = !net_eq(sock_net(sk), dev_net(gtp->dev));
 
 	switch (udp_sk(sk)->encap_type) {
 	case UDP_ENCAP_GTP0:
@@ -658,7 +657,7 @@ static void gtp_link_setup(struct net_de
 static int gtp_hashtable_new(struct gtp_dev *gtp, int hsize);
 static void gtp_hashtable_free(struct gtp_dev *gtp);
 static int gtp_encap_enable(struct net_device *dev, struct gtp_dev *gtp,
-			    int fd_gtp0, int fd_gtp1, struct net *src_net);
+			    int fd_gtp0, int fd_gtp1);
 
 static int gtp_newlink(struct net *src_net, struct net_device *dev,
 			struct nlattr *tb[], struct nlattr *data[])
@@ -675,7 +674,7 @@ static int gtp_newlink(struct net *src_n
 	fd0 = nla_get_u32(data[IFLA_GTP_FD0]);
 	fd1 = nla_get_u32(data[IFLA_GTP_FD1]);
 
-	err = gtp_encap_enable(dev, gtp, fd0, fd1, src_net);
+	err = gtp_encap_enable(dev, gtp, fd0, fd1);
 	if (err < 0)
 		goto out_err;
 
@@ -821,7 +820,7 @@ static void gtp_hashtable_free(struct gt
 }
 
 static int gtp_encap_enable(struct net_device *dev, struct gtp_dev *gtp,
-			    int fd_gtp0, int fd_gtp1, struct net *src_net)
+			    int fd_gtp0, int fd_gtp1)
 {
 	struct udp_tunnel_sock_cfg tuncfg = {NULL};
 	struct socket *sock0, *sock1u;
@@ -858,7 +857,6 @@ static int gtp_encap_enable(struct net_d
 
 	gtp->sock0 = sock0;
 	gtp->sock1u = sock1u;
-	gtp->net = src_net;
 
 	tuncfg.sk_user_data = gtp;
 	tuncfg.encap_rcv = gtp_encap_recv;