xfrm: Flushing empty SAD generates false events

To see the effect make sure you have an empty SAD.
On window1 "ip xfrm mon" and on window2 issue "ip xfrm state flush"
You get prompt back in window2 and you see the flush event on window1.
With this fix, you still get prompt on window1 but no event on window2.

Thanks to Alexey Dobriyan for finding a bug in earlier version
when using pfkey to do the flushing.

Signed-off-by: Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/key/af_key.c b/net/key/af_key.c
index b3faede9a4f6484a4526c38c0530137048437451..c269ce6094d6462be54f656c7bb76d90f8be3f2e 100644 (file)
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -1768,8 +1768,11 @@ static int pfkey_flush(struct sock *sk, struct sk_buff *skb, struct sadb_msg *hd
        audit_info.secid = 0;
        err = xfrm_state_flush(net, proto, &audit_info);
        err2 = unicast_flush_resp(sk, hdr);
-       if (err || err2)
+       if (err || err2) {
+               if (err == -ESRCH) /* empty table - go quietly */
+                       err = 0;
                return err ? err : err2;
+       }
 
        c.data.proto = proto;
        c.seq = hdr->sadb_msg_seq;

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index c9d6a5f1348d296a396288f233ef314ee76ccff9..9fa3322b2a7dda786922f472b6a49a369c40f1ac 100644 (file)
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -603,13 +603,14 @@ xfrm_state_flush_secctx_check(struct net *net, u8 proto, struct xfrm_audit *audi
 
 int xfrm_state_flush(struct net *net, u8 proto, struct xfrm_audit *audit_info)
 {
-       int i, err = 0;
+       int i, err = 0, cnt = 0;
 
        spin_lock_bh(&xfrm_state_lock);
        err = xfrm_state_flush_secctx_check(net, proto, audit_info);
        if (err)
                goto out;
 
+       err = -ESRCH;
        for (i = 0; i <= net->xfrm.state_hmask; i++) {
                struct hlist_node *entry;
                struct xfrm_state *x;
@@ -626,13 +627,16 @@ restart:
                                                        audit_info->sessionid,
                                                        audit_info->secid);
                                xfrm_state_put(x);
+                               if (!err)
+                                       cnt++;
 
                                spin_lock_bh(&xfrm_state_lock);
                                goto restart;
                        }
                }
        }
-       err = 0;
+       if (cnt)
+               err = 0;
 
 out:
        spin_unlock_bh(&xfrm_state_lock);

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 943c8712bd971c6372d0326c3e428630c0981aa4..cd94a9dd1badd29398fc1e06f283a665262ba447 100644 (file)
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1524,8 +1524,11 @@ static int xfrm_flush_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
        audit_info.sessionid = NETLINK_CB(skb).sessionid;
        audit_info.secid = NETLINK_CB(skb).sid;
        err = xfrm_state_flush(net, p->proto, &audit_info);
-       if (err)
+       if (err) {
+               if (err == -ESRCH) /* empty table */
+                       return 0;
                return err;
+       }
        c.data.proto = p->proto;
        c.event = nlh->nlmsg_type;
        c.seq = nlh->nlmsg_seq;