Patch "xfrm: Don't use sk_family for socket policy lookups" has been added to the 4.9-stable tree

Patch "xfrm: Don't use sk_family for socket policy lookups" 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: Don't use sk_family for socket policy lookups

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-don-t-use-sk_family-for-socket-policy-lookups.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 4c86d77743a54fb2d8a4d18a037a074c892bb3be Mon Sep 17 00:00:00 2001
From: Steffen Klassert <steffen.klassert@secunet.com>
Date: Tue, 14 Feb 2017 07:43:56 +0100
Subject: xfrm: Don't use sk_family for socket policy lookups

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

commit 4c86d77743a54fb2d8a4d18a037a074c892bb3be upstream.

On IPv4-mapped IPv6 addresses sk_family is AF_INET6,
but the flow informations are created based on AF_INET.
So the routing set up 'struct flowi4' but we try to
access 'struct flowi6' what leads to an out of bounds
access. Fix this by using the family we get with the
dst_entry, like we do it for the standard policy lookup.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/xfrm/xfrm_policy.c |    9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -1248,7 +1248,7 @@ static inline int policy_to_flow_dir(int
 }
 
 static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
-						 const struct flowi *fl)
+						 const struct flowi *fl, u16 family)
 {
 	struct xfrm_policy *pol;
 
@@ -1256,8 +1256,7 @@ static struct xfrm_policy *xfrm_sk_polic
  again:
 	pol = rcu_dereference(sk->sk_policy[dir]);
 	if (pol != NULL) {
-		bool match = xfrm_selector_match(&pol->selector, fl,
-						 sk->sk_family);
+		bool match = xfrm_selector_match(&pol->selector, fl, family);
 		int err = 0;
 
 		if (match) {
@@ -2206,7 +2205,7 @@ struct dst_entry *xfrm_lookup(struct net
 	sk = sk_const_to_full_sk(sk);
 	if (sk && sk->sk_policy[XFRM_POLICY_OUT]) {
 		num_pols = 1;
-		pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl);
+		pols[0] = xfrm_sk_policy_lookup(sk, XFRM_POLICY_OUT, fl, family);
 		err = xfrm_expand_policies(fl, family, pols,
 					   &num_pols, &num_xfrms);
 		if (err < 0)
@@ -2485,7 +2484,7 @@ int __xfrm_policy_check(struct sock *sk,
 	pol = NULL;
 	sk = sk_to_full_sk(sk);
 	if (sk && sk->sk_policy[dir]) {
-		pol = xfrm_sk_policy_lookup(sk, dir, &fl);
+		pol = xfrm_sk_policy_lookup(sk, dir, &fl, family);
 		if (IS_ERR(pol)) {
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMINPOLERROR);
 			return 0;


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

queue-4.9/xfrm-don-t-use-sk_family-for-socket-policy-lookups.patch
queue-4.9/af_key-add-lock-to-key-dump.patch