xfrm: Add SA to hardware at the end of xfrm_state_construct()

Current code configures the hardware with a new SA before the state has been
fully initialized. During this time interval, an incoming ESP packet can cause
a crash due to a NULL dereference. More specifically, xfrm_input() considers
the packet as valid, and yet, anti-replay mechanism is not initialized.

Move hardware configuration to the end of xfrm_state_construct(), and mark
the state as valid once the SA is fully initialized.

Fixes: d77e38e612a0 ("xfrm: Add an IPsec hardware offloading API")
Signed-off-by: Aviad Yehezkel <aviadye@mellnaox.com>
Signed-off-by: Aviv Heller <avivh@mellanox.com>
Signed-off-by: Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

1 files changed, 11 insertions, 7 deletions

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index bdb48e5dba04..7f52b8eb177d 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -598,13 +598,6 @@ static struct xfrm_state *xfrm_state_construct(struct net *net,
 			goto error;
 	}
 
-	if (attrs[XFRMA_OFFLOAD_DEV]) {
-		err = xfrm_dev_state_add(net, x,
-					 nla_data(attrs[XFRMA_OFFLOAD_DEV]));
-		if (err)
-			goto error;
-	}
-
 	if ((err = xfrm_alloc_replay_state_esn(&x->replay_esn, &x->preplay_esn,
 					       attrs[XFRMA_REPLAY_ESN_VAL])))
 		goto error;
@@ -620,6 +613,14 @@ static struct xfrm_state *xfrm_state_construct(struct net *net,
 	/* override default values from above */
 	xfrm_update_ae_params(x, attrs, 0);
 
+	/* configure the hardware if offload is requested */
+	if (attrs[XFRMA_OFFLOAD_DEV]) {
+		err = xfrm_dev_state_add(net, x,
+					 nla_data(attrs[XFRMA_OFFLOAD_DEV]));
+		if (err)
+			goto error;
+	}
+
 	return x;
 
 error:
@@ -662,6 +663,9 @@ static int xfrm_add_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
 		goto out;
 	}
 
+	if (x->km.state == XFRM_STATE_VOID)
+		x->km.state = XFRM_STATE_VALID;
+
 	c.seq = nlh->nlmsg_seq;
 	c.portid = nlh->nlmsg_pid;
 	c.event = nlh->nlmsg_type;