Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec

Steffen Klassert says:

====================
pull request (net): ipsec 2018-12-18

1) Fix error return code in xfrm_output_one()
   when no dst_entry is attached to the skb.
   From Wei Yongjun.

2) The xfrm state hash bucket count reported to
   userspace is off by one. Fix from Benjamin Poirier.

3) Fix NULL pointer dereference in xfrm_input when
   skb_dst_force clears the dst_entry.

4) Fix freeing of xfrm states on acquire. We use a
   dedicated slab cache for the xfrm states now,
   so free it properly with kmem_cache_free.
   From Mathias Krause.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 17 insertions, 5 deletions

diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
index 684c0bc01e2c..d5635908587f 100644
--- a/net/xfrm/xfrm_input.c
+++ b/net/xfrm/xfrm_input.c
@@ -346,6 +346,12 @@ int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type)
 
 		skb->sp->xvec[skb->sp->len++] = x;
 
+		skb_dst_force(skb);
+		if (!skb_dst(skb)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
+			goto drop;
+		}
+
 lock:
 		spin_lock(&x->lock);
 
@@ -385,7 +391,6 @@ lock:
 		XFRM_SKB_CB(skb)->seq.input.low = seq;
 		XFRM_SKB_CB(skb)->seq.input.hi = seq_hi;
 
-		skb_dst_force(skb);
 		dev_hold(skb->dev);
 
 		if (crypto_done)
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index 4ae87c5ce2e3..fef6b2da3c5d 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -102,6 +102,7 @@ static int xfrm_output_one(struct sk_buff *skb, int err)
 		skb_dst_force(skb);
 		if (!skb_dst(skb)) {
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
+			err = -EHOSTUNREACH;
 			goto error_nolock;
 		}
 
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index dc4a9f1fb941..23c92891758a 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -426,6 +426,12 @@ static void xfrm_put_mode(struct xfrm_mode *mode)
 	module_put(mode->owner);
 }
 
+void xfrm_state_free(struct xfrm_state *x)
+{
+	kmem_cache_free(xfrm_state_cache, x);
+}
+EXPORT_SYMBOL(xfrm_state_free);
+
 static void xfrm_state_gc_destroy(struct xfrm_state *x)
 {
 	tasklet_hrtimer_cancel(&x->mtimer);
@@ -452,7 +458,7 @@ static void xfrm_state_gc_destroy(struct xfrm_state *x)
 	}
 	xfrm_dev_state_free(x);
 	security_xfrm_state_free(x);
-	kmem_cache_free(xfrm_state_cache, x);
+	xfrm_state_free(x);
 }
 
 static void xfrm_state_gc_task(struct work_struct *work)
@@ -788,7 +794,7 @@ void xfrm_sad_getinfo(struct net *net, struct xfrmk_sadinfo *si)
 {
 	spin_lock_bh(&net->xfrm.xfrm_state_lock);
 	si->sadcnt = net->xfrm.state_num;
-	si->sadhcnt = net->xfrm.state_hmask;
+	si->sadhcnt = net->xfrm.state_hmask + 1;
 	si->sadhmcnt = xfrm_state_hashmax;
 	spin_unlock_bh(&net->xfrm.xfrm_state_lock);
 }
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index c9a84e22f5d5..277c1c46fe94 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2288,13 +2288,13 @@ static int xfrm_add_acquire(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 	}
 
-	kfree(x);
+	xfrm_state_free(x);
 	kfree(xp);
 
 	return 0;
 
 free_state:
-	kfree(x);
+	xfrm_state_free(x);
 nomem:
 	return err;
 }