[3.13.y.z extended stable] Patch "net/l2tp: don't fall back on UDP [get|set]sockopt" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    net/l2tp: don't fall back on UDP [get|set]sockopt

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.6.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 03a56ed69932cbe006265236ac23f5caeaa08a3f Mon Sep 17 00:00:00 2001
From: Sasha Levin <sasha.levin at oracle.com>
Date: Mon, 14 Jul 2014 17:02:31 -0700
Subject: net/l2tp: don't fall back on UDP [get|set]sockopt

commit 3cf521f7dc87c031617fd47e4b7aa2593c2f3daf upstream.

The l2tp [get|set]sockopt() code has fallen back to the UDP functions
for socket option levels != SOL_PPPOL2TP since day one, but that has
never actually worked, since the l2tp socket isn't an inet socket.

As David Miller points out:

  "If we wanted this to work, it'd have to look up the tunnel and then
   use tunnel->sk, but I wonder how useful that would be"

Since this can never have worked so nobody could possibly have depended
on that functionality, just remove the broken code and return -EINVAL.

Reported-by: Sasha Levin <sasha.levin at oracle.com>
Acked-by: James Chapman <jchapman at katalix.com>
Acked-by: David Miller <davem at davemloft.net>
Cc: Phil Turnbull <phil.turnbull at oracle.com>
Cc: Vegard Nossum <vegard.nossum at oracle.com>
Cc: Willy Tarreau <w at 1wt.eu>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 net/l2tp/l2tp_ppp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
index 8580b78..cfa1406 100644
--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -1365,7 +1365,7 @@ static int pppol2tp_setsockopt(struct socket *sock, int level, int optname,
 	int err;

 	if (level != SOL_PPPOL2TP)
-		return udp_prot.setsockopt(sk, level, optname, optval, optlen);
+		return -EINVAL;

 	if (optlen < sizeof(int))
 		return -EINVAL;
@@ -1491,7 +1491,7 @@ static int pppol2tp_getsockopt(struct socket *sock, int level, int optname,
 	struct pppol2tp_session *ps;

 	if (level != SOL_PPPOL2TP)
-		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
+		return -EINVAL;

 	if (get_user(len, optlen))
 		return -EFAULT;
--
1.9.1