Patch "xfrm: Refuse to insert 32 bit userspace socket policies on 64 bit systems" has been added to the 4.9-stable tree

Patch "xfrm: Refuse to insert 32 bit userspace socket policies on 64 bit systems" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    xfrm: Refuse to insert 32 bit userspace socket policies on 64 bit systems

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     xfrm-refuse-to-insert-32-bit-userspace-socket-policies-on-64-bit-systems.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 19d7df69fdb2636856dc8919de72fc1bf8f79598 Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Thu, 1 Feb 2018 08:49:23 +0100
Subject: xfrm: Refuse to insert 32 bit userspace socket policies on 64 bit systems

From: Steffen Klassert <steffen.klassert@secunet.com>

commit 19d7df69fdb2636856dc8919de72fc1bf8f79598 upstream.

We don't have a compat layer for xfrm, so userspace and kernel
structures have different sizes in this case. This results in
a broken configuration, so refuse to configure socket policies
when trying to insert from 32 bit userspace as we do it already
with policies inserted via netlink.

Reported-and-tested-by: syzbot+e1a1577ca8bcb47b769a@syzkaller.appspotmail.com
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/xfrm/xfrm_state.c |    5 +++++
 1 file changed, 5 insertions(+)

--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -1883,6 +1883,11 @@ int xfrm_user_policy(struct sock *sk, in
 	struct xfrm_mgr *km;
 	struct xfrm_policy *pol = NULL;
 
+#ifdef CONFIG_COMPAT
+	if (in_compat_syscall())
+		return -EOPNOTSUPP;
+#endif
+
 	if (!optval && !optlen) {
 		xfrm_sk_policy_insert(sk, XFRM_POLICY_IN, NULL);
 		xfrm_sk_policy_insert(sk, XFRM_POLICY_OUT, NULL);


Patches currently in stable-queue which might be from steffen.klassert@secunet.com are

queue-4.9/xfrm_user-uncoditionally-validate-esn-replay-attribute-struct.patch
queue-4.9/xfrm-refuse-to-insert-32-bit-userspace-socket-policies-on-64-bit-systems.patch
queue-4.9/net-xfrm-use-preempt-safe-this_cpu_read-in-ipcomp_alloc_tfms.patch