xfrm: notify default policy on update

This configuration knob is very sensible, it should be notified when
changing.

Fixes: 2d151d39073a ("xfrm: Add possibility to set the default to block if we have no policy")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 90c8839..0eba0c2 100644 (file)
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1961,6 +1961,36 @@ static struct sk_buff *xfrm_policy_netlink(struct sk_buff *in_skb,
        return skb;
 }
 
+static int xfrm_notify_userpolicy(struct net *net)
+{
+       struct xfrm_userpolicy_default *up;
+       int len = NLMSG_ALIGN(sizeof(*up));
+       struct nlmsghdr *nlh;
+       struct sk_buff *skb;
+
+       skb = nlmsg_new(len, GFP_ATOMIC);
+       if (skb == NULL)
+               return -ENOMEM;
+
+       nlh = nlmsg_put(skb, 0, 0, XFRM_MSG_GETDEFAULT, sizeof(*up), 0);
+       if (nlh == NULL) {
+               kfree_skb(skb);
+               return -EMSGSIZE;
+       }
+
+       up = nlmsg_data(nlh);
+       up->in = net->xfrm.policy_default & XFRM_POL_DEFAULT_IN ?
+                       XFRM_USERPOLICY_BLOCK : XFRM_USERPOLICY_ACCEPT;
+       up->fwd = net->xfrm.policy_default & XFRM_POL_DEFAULT_FWD ?
+                       XFRM_USERPOLICY_BLOCK : XFRM_USERPOLICY_ACCEPT;
+       up->out = net->xfrm.policy_default & XFRM_POL_DEFAULT_OUT ?
+                       XFRM_USERPOLICY_BLOCK : XFRM_USERPOLICY_ACCEPT;
+
+       nlmsg_end(skb, nlh);
+
+       return xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_POLICY);
+}
+
 static int xfrm_set_default(struct sk_buff *skb, struct nlmsghdr *nlh,
                            struct nlattr **attrs)
 {
@@ -1984,6 +2014,7 @@ static int xfrm_set_default(struct sk_buff *skb, struct nlmsghdr *nlh,
 
        rt_genid_bump_all(net);
 
+       xfrm_notify_userpolicy(net);
        return 0;
 }