Patch "xfrm: Fix xfrm_input() to verify state is valid when (encap_type < 0)" has been added to the 4.14-stable tree

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

xfrm: Fix xfrm_input() to verify state is valid when (encap_type < 0)

to the 4.14-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-fix-xfrm_input-to-verify-state-is-valid-when-encap_type-0.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Aviv Heller <[email protected]>
Date: Tue, 28 Nov 2017 19:55:40 +0200
Subject: xfrm: Fix xfrm_input() to verify state is valid when (encap_type < 0)

From: Aviv Heller <[email protected]>

[ Upstream commit 4ce3dbe397d7b6b15f272ae757c78c35e9e4b61d ]

Code path when (encap_type < 0) does not verify the state is valid before progressing.

This will result in a crash if, for instance, x->km.state == XFRM_STATE_ACQ.

---
 net/xfrm/xfrm_input.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

@@ -207,7 +207,7 @@ int xfrm_input(struct sk_buff *skb, int
 	xfrm_address_t *daddr;
 	struct xfrm_mode *inner_mode;
 	u32 mark = skb->mark;
-	unsigned int family;
+	unsigned int family = AF_UNSPEC;
 	int decaps = 0;
 	int async = 0;
 	bool xfrm_gro = false;

@@ -216,6 +216,16 @@ int xfrm_input(struct sk_buff *skb, int
 
 	if (encap_type < 0) {
 		x = xfrm_input_state(skb);
+
+		if (unlikely(x->km.state != XFRM_STATE_VALID)) {
+			if (x->km.state == XFRM_STATE_ACQ)
+				XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
+			else
+				XFRM_INC_STATS(net,
+					       LINUX_MIB_XFRMINSTATEINVALID);
+			goto drop;
+		}
+
 		family = x->outer_mode->afinfo->family;
 
 		/* An encap_type of -1 indicates async resumption. */

Patches currently in stable-queue which might be from [email protected] are

queue-4.14/xfrm-fix-xfrm_input-to-verify-state-is-valid-when-encap_type-0.patch