xfrm: Flushing empty SAD generates false events

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

I was tempted to return -ESRCH on window1 (which would
show "RTNETLINK answers: No such process") but didnt want
to change current behavior.

cheers,
jamal
commit 5f3dd4a772326166e1bcf54acc2391df00dc7ab5
Author: Jamal Hadi Salim <hadi@cyberus.ca>
Date:   Thu Feb 11 04:41:36 2010 -0500

    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 window1 and you see the flush event on window2.
    With this fix, you still get prompt on window1 but no event on window2.

    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 79d2c0f3c334e18c49f75c127a2fbedd194ab16a..9d47a6aa53dc109228bfa961bfb12fc99d5327dc 100644 (file)
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -1751,7 +1751,7 @@ 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);
        if (err)
-               return err;
+               return 0;
        c.data.proto = proto;
        c.seq = hdr->sadb_msg_seq;
        c.pid = hdr->sadb_msg_pid;

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index b36cc344474b33a76d6d257d4a8f6474ef3ba204..f50ee9badf47a39ab2ec9a75e542f5932b956a79 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..7c87004470409fa3f4554d6ea0bba0d72032022f 100644 (file)
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1525,7 +1525,7 @@ static int xfrm_flush_sa(struct sk_buff *skb, struct nlmsghdr *nlh,
        audit_info.secid = NETLINK_CB(skb).sid;
        err = xfrm_state_flush(net, p->proto, &audit_info);
        if (err)
-               return err;
+               return 0;
        c.data.proto = p->proto;
        c.event = nlh->nlmsg_type;
        c.seq = nlh->nlmsg_seq;