Patch "af_key: Fix sadb_x_ipsecrequest parsing" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

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

    af_key: Fix sadb_x_ipsecrequest parsing

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:
     af_key-fix-sadb_x_ipsecrequest-parsing.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 096f41d3a8fcbb8dde7f71379b1ca85fe213eded Mon Sep 17 00:00:00 2001
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Thu, 13 Apr 2017 18:35:59 +0800
Subject: af_key: Fix sadb_x_ipsecrequest parsing

From: Herbert Xu <herbert@gondor.apana.org.au>

commit 096f41d3a8fcbb8dde7f71379b1ca85fe213eded upstream.

The parsing of sadb_x_ipsecrequest is broken in a number of ways.
First of all we're not verifying sadb_x_ipsecrequest_len.  This
is needed when the structure carries addresses at the end.  Worse
we don't even look at the length when we parse those optional
addresses.

The migration code had similar parsing code that's better but
it also has some deficiencies.  The length is overcounted first
of all as it includes the header itself.  It also fails to check
the length before dereferencing the sa_family field.

This patch fixes those problems in parse_sockaddr_pair and then
uses it in parse_ipsecrequest.

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/key/af_key.c |   47 ++++++++++++++++++++++++++---------------------
 1 file changed, 26 insertions(+), 21 deletions(-)

--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -65,6 +65,10 @@ struct pfkey_sock {
 	} dump;
 };
 
+static int parse_sockaddr_pair(struct sockaddr *sa, int ext_len,
+			       xfrm_address_t *saddr, xfrm_address_t *daddr,
+			       u16 *family);
+
 static inline struct pfkey_sock *pfkey_sk(struct sock *sk)
 {
 	return (struct pfkey_sock *)sk;
@@ -1922,19 +1926,14 @@ parse_ipsecrequest(struct xfrm_policy *x
 
 	/* addresses present only in tunnel mode */
 	if (t->mode == XFRM_MODE_TUNNEL) {
-		u8 *sa = (u8 *) (rq + 1);
-		int family, socklen;
+		int err;
 
-		family = pfkey_sockaddr_extract((struct sockaddr *)sa,
-						&t->saddr);
-		if (!family)
-			return -EINVAL;
-
-		socklen = pfkey_sockaddr_len(family);
-		if (pfkey_sockaddr_extract((struct sockaddr *)(sa + socklen),
-					   &t->id.daddr) != family)
-			return -EINVAL;
-		t->encap_family = family;
+		err = parse_sockaddr_pair(
+			(struct sockaddr *)(rq + 1),
+			rq->sadb_x_ipsecrequest_len - sizeof(*rq),
+			&t->saddr, &t->id.daddr, &t->encap_family);
+		if (err)
+			return err;
 	} else
 		t->encap_family = xp->family;
 
@@ -1954,7 +1953,11 @@ parse_ipsecrequests(struct xfrm_policy *
 	if (pol->sadb_x_policy_len * 8 < sizeof(struct sadb_x_policy))
 		return -EINVAL;
 
-	while (len >= sizeof(struct sadb_x_ipsecrequest)) {
+	while (len >= sizeof(*rq)) {
+		if (len < rq->sadb_x_ipsecrequest_len ||
+		    rq->sadb_x_ipsecrequest_len < sizeof(*rq))
+			return -EINVAL;
+
 		if ((err = parse_ipsecrequest(xp, rq)) < 0)
 			return err;
 		len -= rq->sadb_x_ipsecrequest_len;
@@ -2417,7 +2420,6 @@ out:
 	return err;
 }
 
-#ifdef CONFIG_NET_KEY_MIGRATE
 static int pfkey_sockaddr_pair_size(sa_family_t family)
 {
 	return PFKEY_ALIGN8(pfkey_sockaddr_len(family) * 2);
@@ -2429,7 +2431,7 @@ static int parse_sockaddr_pair(struct so
 {
 	int af, socklen;
 
-	if (ext_len < pfkey_sockaddr_pair_size(sa->sa_family))
+	if (ext_len < 2 || ext_len < pfkey_sockaddr_pair_size(sa->sa_family))
 		return -EINVAL;
 
 	af = pfkey_sockaddr_extract(sa, saddr);
@@ -2445,6 +2447,7 @@ static int parse_sockaddr_pair(struct so
 	return 0;
 }
 
+#ifdef CONFIG_NET_KEY_MIGRATE
 static int ipsecrequests_to_migrate(struct sadb_x_ipsecrequest *rq1, int len,
 				    struct xfrm_migrate *m)
 {
@@ -2452,13 +2455,14 @@ static int ipsecrequests_to_migrate(stru
 	struct sadb_x_ipsecrequest *rq2;
 	int mode;
 
-	if (len <= sizeof(struct sadb_x_ipsecrequest) ||
-	    len < rq1->sadb_x_ipsecrequest_len)
+	if (len < sizeof(*rq1) ||
+	    len < rq1->sadb_x_ipsecrequest_len ||
+	    rq1->sadb_x_ipsecrequest_len < sizeof(*rq1))
 		return -EINVAL;
 
 	/* old endoints */
 	err = parse_sockaddr_pair((struct sockaddr *)(rq1 + 1),
-				  rq1->sadb_x_ipsecrequest_len,
+				  rq1->sadb_x_ipsecrequest_len - sizeof(*rq1),
 				  &m->old_saddr, &m->old_daddr,
 				  &m->old_family);
 	if (err)
@@ -2467,13 +2471,14 @@ static int ipsecrequests_to_migrate(stru
 	rq2 = (struct sadb_x_ipsecrequest *)((u8 *)rq1 + rq1->sadb_x_ipsecrequest_len);
 	len -= rq1->sadb_x_ipsecrequest_len;
 
-	if (len <= sizeof(struct sadb_x_ipsecrequest) ||
-	    len < rq2->sadb_x_ipsecrequest_len)
+	if (len <= sizeof(*rq2) ||
+	    len < rq2->sadb_x_ipsecrequest_len ||
+	    rq2->sadb_x_ipsecrequest_len < sizeof(*rq2))
 		return -EINVAL;
 
 	/* new endpoints */
 	err = parse_sockaddr_pair((struct sockaddr *)(rq2 + 1),
-				  rq2->sadb_x_ipsecrequest_len,
+				  rq2->sadb_x_ipsecrequest_len - sizeof(*rq2),
 				  &m->new_saddr, &m->new_daddr,
 				  &m->new_family);
 	if (err)


Patches currently in stable-queue which might be from herbert@gondor.apana.org.au are

queue-4.9/af_key-fix-sadb_x_ipsecrequest-parsing.patch