commit baab2ce7d2a8dbf6280ab09c011cfec1dd5972de
author Patrick McHardy <kaber@trash.net> Mon Dec 17 22:41:21 2007 -0800
committer David S. Miller <davem@davemloft.net> Mon Jan 28 14:59:02 2008 -0800
tree 60cc03f14468a7244ae49a621eaeb8f2dbac84e9
parent 1792bab4caaa85bae858799bb6231f171f59b58a

[NETFILTER]: nfnetlink_{queue,log}: return proper error codes in instance_create

Currently we return EINVAL for "instance exists", "allocation failed" and
"module unloaded below us", which is completely inapproriate.

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

net/netfilter/nfnetlink_queue.c

diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index 370f0af..51476f8 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -89,16 +89,21 @@
 static struct nfqnl_instance *
 instance_create(u_int16_t queue_num, int pid)
 {
-	struct nfqnl_instance *inst = NULL;
+	struct nfqnl_instance *inst;
 	unsigned int h;
+	int err;
 
 	spin_lock(&instances_lock);
-	if (instance_lookup(queue_num))
+	if (instance_lookup(queue_num)) {
+		err = -EEXIST;
 		goto out_unlock;
+	}
 
 	inst = kzalloc(sizeof(*inst), GFP_ATOMIC);
-	if (!inst)
+	if (!inst) {
+		err = -ENOMEM;
 		goto out_unlock;
+	}
 
 	inst->queue_num = queue_num;
 	inst->peer_pid = pid;
@@ -109,8 +114,10 @@
 	INIT_LIST_HEAD(&inst->queue_list);
 	INIT_RCU_HEAD(&inst->rcu);
 
-	if (!try_module_get(THIS_MODULE))
+	if (!try_module_get(THIS_MODULE)) {
+		err = -EAGAIN;
 		goto out_free;
+	}
 
 	h = instance_hashfn(queue_num);
 	hlist_add_head_rcu(&inst->hlist, &instance_table[h]);
@@ -123,7 +130,7 @@
 	kfree(inst);
 out_unlock:
 	spin_unlock(&instances_lock);
-	return NULL;
+	return ERR_PTR(err);
 }
 
 static void nfqnl_flush(struct nfqnl_instance *queue, nfqnl_cmpfn cmpfn,
@@ -724,8 +731,8 @@
 				goto err_out_unlock;
 			}
 			queue = instance_create(queue_num, NETLINK_CB(skb).pid);
-			if (!queue) {
-				ret = -EINVAL;
+			if (IS_ERR(queue)) {
+				ret = PTR_ERR(queue);
 				goto err_out_unlock;
 			}
 			break;