[NETFILTER]: nf_conntrack: simplify l4 protocol array allocation
authorPatrick McHardy <kaber@trash.net>
Wed, 14 Mar 2007 23:39:07 +0000 (16:39 -0700)
committerDavid S. Miller <davem@sunset.davemloft.net>
Thu, 26 Apr 2007 05:25:43 +0000 (22:25 -0700)
The retrying after an allocation failure is not necessary anymore
since we're holding the mutex the entire time, for the same
reason the double allocation race can't happen anymore.

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

index 509725412d3b76e32678bebcead4694060999049..e4aad2087f4deeb30a99b86c9b46f4108579ac64 100644 (file)
@@ -281,47 +281,34 @@ int nf_conntrack_l4proto_register(struct nf_conntrack_l4proto *l4proto)
                return -EBUSY;
 
        mutex_lock(&nf_ct_proto_mutex);
-retry:
-       if (nf_ct_protos[l4proto->l3proto]) {
-               if (nf_ct_protos[l4proto->l3proto][l4proto->l4proto]
-                               != &nf_conntrack_l4proto_generic) {
-                       ret = -EBUSY;
-                       goto out_unlock;
-               }
-       } else {
+       if (!nf_ct_protos[l4proto->l3proto]) {
                /* l3proto may be loaded latter. */
                struct nf_conntrack_l4proto **proto_array;
                int i;
 
-               proto_array = (struct nf_conntrack_l4proto **)
-                               kmalloc(MAX_NF_CT_PROTO *
-                                        sizeof(struct nf_conntrack_l4proto *),
-                                       GFP_KERNEL);
+               proto_array = kmalloc(MAX_NF_CT_PROTO *
+                                     sizeof(struct nf_conntrack_l4proto *),
+                                     GFP_KERNEL);
                if (proto_array == NULL) {
                        ret = -ENOMEM;
                        goto out_unlock;
                }
+
                for (i = 0; i < MAX_NF_CT_PROTO; i++)
                        proto_array[i] = &nf_conntrack_l4proto_generic;
-
-               if (nf_ct_protos[l4proto->l3proto])
-                       /* bad timing, but no problem */
-                       kfree(proto_array);
-               else
-                       nf_ct_protos[l4proto->l3proto] = proto_array;
-
-               /*
-                * Just once because array is never freed until unloading
-                * nf_conntrack.ko
-                */
-               goto retry;
+               nf_ct_protos[l4proto->l3proto] = proto_array;
+       } else if (nf_ct_protos[l4proto->l3proto][l4proto->l4proto] !=
+                                       &nf_conntrack_l4proto_generic) {
+               ret = -EBUSY;
+               goto out_unlock;
        }
 
        ret = nf_ct_l4proto_register_sysctl(l4proto);
        if (ret < 0)
                goto out_unlock;
 
-       rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto], l4proto);
+       rcu_assign_pointer(nf_ct_protos[l4proto->l3proto][l4proto->l4proto],
+                          l4proto);
 
 out_unlock:
        mutex_unlock(&nf_ct_proto_mutex);