netfilter: nfnetlink_queue: do not free skb on error

Move free responsibility from nf_queue to caller.
This enables more flexible error handling; we can now accept the skb
instead of freeing it.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

diff --git a/net/netfilter/core.c b/net/netfilter/core.c
index 91d66d2..0c5b796 100644 (file)
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@ -181,8 +181,11 @@ next_hook:
        } else if ((verdict & NF_VERDICT_MASK) == NF_QUEUE) {
                ret = nf_queue(skb, elem, pf, hook, indev, outdev, okfn,
                               verdict >> NF_VERDICT_BITS);
-               if (ret == -ECANCELED)
-                       goto next_hook;
+               if (ret < 0) {
+                       if (ret == -ECANCELED)
+                               goto next_hook;
+                       kfree_skb(skb);
+               }
                ret = 0;
        }
        rcu_read_unlock();

diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c
index ad25c7e..5c4b730 100644 (file)
--- a/net/netfilter/nf_queue.c
+++ b/net/netfilter/nf_queue.c
@@ -163,9 +163,8 @@ static int __nf_queue(struct sk_buff *skb,
 
        /* If it's going away, ignore hook. */
        if (!try_module_get(entry->elem->owner)) {
-               rcu_read_unlock();
-               kfree(entry);
-               return -ECANCELED;
+               status = -ECANCELED;
+               goto err_unlock;
        }
        /* Bump dev refs so they don't vanish while packet is out */
        if (indev)
@@ -198,7 +197,6 @@ static int __nf_queue(struct sk_buff *skb,
 err_unlock:
        rcu_read_unlock();
 err:
-       kfree_skb(skb);
        kfree(entry);
        return status;
 }
@@ -229,7 +227,6 @@ int nf_queue(struct sk_buff *skb,
        }
 
        segs = skb_gso_segment(skb, 0);
-       kfree_skb(skb);
        /* Does not use PTR_ERR to limit the number of error codes that can be
         * returned by nf_queue.  For instance, callers rely on -ECANCELED to mean
         * 'ignore this hook'.
@@ -253,8 +250,11 @@ int nf_queue(struct sk_buff *skb,
                segs = nskb;
        } while (segs);
 
+       /* also free orig skb if only some segments were queued */
        if (unlikely(err && queued))
                err = 0;
+       if (err == 0)
+               kfree_skb(skb);
        return err;
 }
 
@@ -300,8 +300,11 @@ void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict)
                err = __nf_queue(skb, elem, entry->pf, entry->hook,
                                 entry->indev, entry->outdev, entry->okfn,
                                 verdict >> NF_VERDICT_BITS);
-               if (err == -ECANCELED)
-                       goto next_hook;
+               if (err < 0) {
+                       if (err == -ECANCELED)
+                               goto next_hook;
+                       kfree_skb(skb);
+               }
                break;
        case NF_STOLEN:
        default: