From cbb95e0ca92869cc94a1c5e5ac58395afbbda26e Mon Sep 17 00:00:00 2001 From: Tom Parkin Date: Thu, 31 Jan 2013 23:43:02 +0000 Subject: [PATCH] l2tp: prevent tunnel creation on netns mismatch l2tp_tunnel_create is passed a pointer to the network namespace for the tunnel, along with an optional file descriptor for the tunnel which may be passed in from userspace via. netlink. In the case where the file descriptor is defined, ensure that the namespace associated with that socket matches the namespace explicitly passed to l2tp_tunnel_create. Signed-off-by: Tom Parkin Signed-off-by: James Chapman Signed-off-by: David S. Miller --- net/l2tp/l2tp_core.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c index 73988c070561..60a498a459dd 100644 --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -1593,11 +1593,18 @@ int l2tp_tunnel_create(struct net *net, int fd, int version, u32 tunnel_id, u32 if (err < 0) goto err; } else { - err = -EBADF; sock = sockfd_lookup(fd, &err); if (!sock) { - pr_err("tunl %hu: sockfd_lookup(fd=%d) returned %d\n", + pr_err("tunl %u: sockfd_lookup(fd=%d) returned %d\n", tunnel_id, fd, err); + err = -EBADF; + goto err; + } + + /* Reject namespace mismatches */ + if (!net_eq(sock_net(sock->sk), net)) { + pr_err("tunl %u: netns mismatch\n", tunnel_id); + err = -EINVAL; goto err; } } -- 2.20.1