[PATCH 75/78] ipv6,gre: do not leak info to user-space

[Kamal Mostafa]

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

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

From: Amerigo Wang <amwang at redhat.com>

[ Upstream commit 5dbd5068430b8bd1c19387d46d6c1a88b261257f ]

There is a hole in struct ip6_tnl_parm2, so we have to
zero the struct on stack before copying it to user-space.

Cc: David S. Miller <davem at davemloft.net>
Signed-off-by: Cong Wang <amwang at redhat.com>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/ipv6/ip6_gre.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 131dd09..a4c5ae7 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -1137,6 +1137,7 @@ static int ip6gre_tunnel_ioctl(struct net_device *dev,
 		}
 		if (t == NULL)
 			t = netdev_priv(dev);
+		memset(&p, 0, sizeof(p));
 		ip6gre_tnl_parm_to_user(&p, &t->parms);
 		if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
 			err = -EFAULT;
@@ -1184,6 +1185,7 @@ static int ip6gre_tunnel_ioctl(struct net_device *dev,
 		if (t) {
 			err = 0;
 
+			memset(&p, 0, sizeof(p));
 			ip6gre_tnl_parm_to_user(&p, &t->parms);
 			if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
 				err = -EFAULT;
-- 
1.8.1.2