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[Utopic/goldfish,manta,mako,flo,CVE-2014-4943] net/l2tp: don't fall back on UDP [get|set]sockopt

Message ID 1409675425-18496-1-git-send-email-luis.henriques@canonical.com
State New
Headers show

Commit Message

Luis Henriques Sept. 2, 2014, 4:30 p.m. UTC 
From: Sasha Levin <sasha.levin@oracle.com>

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@oracle.com>
Acked-by: James Chapman <jchapman@katalix.com>
Acked-by: David Miller <davem@davemloft.net>
Cc: Phil Turnbull <phil.turnbull@oracle.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 3cf521f7dc87c031617fd47e4b7aa2593c2f3daf)
CVE-2014-4943
BugLink: http://bugs.launchpad.net/bugs/1341472
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
---
 net/l2tp/l2tp_ppp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Tim Gardner Sept. 3, 2014, 7:54 p.m. UTC | #1
diff mbox

Patch

diff --git a/net/l2tp/l2tp_ppp.c b/net/l2tp/l2tp_ppp.c
index 1addd9f3f40a..efb0138948b1 100644
--- a/net/l2tp/l2tp_ppp.c
+++ b/net/l2tp/l2tp_ppp.c
@@ -1348,7 +1348,7 @@  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;
@@ -1474,7 +1474,7 @@  static int pppol2tp_getsockopt(struct socket *sock, int level,
 	struct pppol2tp_session *ps;
 
 	if (level != SOL_PPPOL2TP)
-		return udp_prot.getsockopt(sk, level, optname, optval, optlen);
+		return -EINVAL;
 
 	if (get_user(len, (int __user *) optlen))
 		return -EFAULT;