[NETFILTER]: nf_conntrack_expect: avoid useless list walking

Don't walk the list when unexpecting an expectation, we already
have a reference and the timer check is enough to guarantee
that it still is on the list.

This comment suggests that it was copied there by mistake from
expectation eviction:

/* choose the oldest expectation to evict */

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/netfilter/nf_conntrack_expect.c b/net/netfilter/nf_conntrack_expect.c
index 83b5ad8..5c8cb0f 100644 (file)
--- a/net/netfilter/nf_conntrack_expect.c
+++ b/net/netfilter/nf_conntrack_expect.c
@@ -165,17 +165,10 @@ static inline int expect_matches(const struct nf_conntrack_expect *a,
 /* Generally a bad idea to call this: could have matched already. */
 void nf_ct_unexpect_related(struct nf_conntrack_expect *exp)
 {
-       struct nf_conntrack_expect *i;
-
        write_lock_bh(&nf_conntrack_lock);
-       /* choose the oldest expectation to evict */
-       list_for_each_entry_reverse(i, &nf_ct_expect_list, list) {
-               if (expect_matches(i, exp) && del_timer(&i->timeout)) {
-                       nf_ct_unlink_expect(i);
-                       write_unlock_bh(&nf_conntrack_lock);
-                       nf_ct_expect_put(i);
-                       return;
-               }
+       if (del_timer(&exp->timeout)) {
+               nf_ct_unlink_expect(exp);
+               nf_ct_expect_put(exp);
        }
        write_unlock_bh(&nf_conntrack_lock);
 }