[NETFILTER]: nf_queue: handle GSO packets

Handle GSO packets in nf_queue by segmenting them before queueing to
avoid breaking GSO in case they get mangled.

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

3 files changed, 62 insertions, 22 deletions

diff --git a/net/netfilter/core.c b/net/netfilter/core.c
index 27f639f3ac2..d80b935b3a9 100644
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@ -182,7 +182,7 @@ next_hook:
                 ret = -EPERM;
         } else if ((verdict & NF_VERDICT_MASK)  == NF_QUEUE) {
                 NFDEBUG("nf_hook: Verdict = QUEUE.\n");
-                if (!nf_queue(pskb, elem, pf, hook, indev, outdev, okfn,
+                if (!nf_queue(*pskb, elem, pf, hook, indev, outdev, okfn,
                               verdict >> NF_VERDICT_BITS))
                         goto next_hook;
         }
diff --git a/net/netfilter/nf_internals.h b/net/netfilter/nf_internals.h
index 86e392bfe83..a981971ce1d 100644
--- a/net/netfilter/nf_internals.h
+++ b/net/netfilter/nf_internals.h
@@ -23,7 +23,7 @@ extern unsigned int nf_iterate(struct list_head *head,
                                 int hook_thresh);
 
 /* nf_queue.c */
-extern int nf_queue(struct sk_buff **skb, 
+extern int nf_queue(struct sk_buff *skb,
                     struct list_head *elem, 
                     int pf, unsigned int hook,
                     struct net_device *indev,
diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c
index 662a869593b..4d8936ed581 100644
--- a/net/netfilter/nf_queue.c
+++ b/net/netfilter/nf_queue.c
@@ -74,13 +74,13 @@ EXPORT_SYMBOL_GPL(nf_unregister_queue_handlers);
  * Any packet that leaves via this function must come back 
  * through nf_reinject().
  */
-int nf_queue(struct sk_buff **skb, 
-             struct list_head *elem, 
-             int pf, unsigned int hook,
-             struct net_device *indev,
-             struct net_device *outdev,
-             int (*okfn)(struct sk_buff *),
-             unsigned int queuenum)
+static int __nf_queue(struct sk_buff *skb,
+                      struct list_head *elem,
+                      int pf, unsigned int hook,
+                      struct net_device *indev,
+                      struct net_device *outdev,
+                      int (*okfn)(struct sk_buff *),
+                      unsigned int queuenum)
 {
         int status;
         struct nf_info *info;
@@ -94,14 +94,14 @@ int nf_queue(struct sk_buff **skb,
         read_lock(&queue_handler_lock);
         if (!queue_handler[pf]) {
                 read_unlock(&queue_handler_lock);
-                kfree_skb(*skb);
+                kfree_skb(skb);
                 return 1;
         }
 
         afinfo = nf_get_afinfo(pf);
         if (!afinfo) {
                 read_unlock(&queue_handler_lock);
-                kfree_skb(*skb);
+                kfree_skb(skb);
                 return 1;
         }
 
@@ -109,9 +109,9 @@ int nf_queue(struct sk_buff **skb,
         if (!info) {
                 if (net_ratelimit())
                         printk(KERN_ERR "OOM queueing packet %p\n",
-                               *skb);
+                               skb);
                 read_unlock(&queue_handler_lock);
-                kfree_skb(*skb);
+                kfree_skb(skb);
                 return 1;
         }
 
@@ -130,15 +130,15 @@ int nf_queue(struct sk_buff **skb,
         if (outdev) dev_hold(outdev);
 
 #ifdef CONFIG_BRIDGE_NETFILTER
-        if ((*skb)->nf_bridge) {
-                physindev = (*skb)->nf_bridge->physindev;
+        if (skb->nf_bridge) {
+                physindev = skb->nf_bridge->physindev;
                 if (physindev) dev_hold(physindev);
-                physoutdev = (*skb)->nf_bridge->physoutdev;
+                physoutdev = skb->nf_bridge->physoutdev;
                 if (physoutdev) dev_hold(physoutdev);
         }
 #endif
-        afinfo->saveroute(*skb, info);
-        status = queue_handler[pf]->outfn(*skb, info, queuenum,
+        afinfo->saveroute(skb, info);
+        status = queue_handler[pf]->outfn(skb, info, queuenum,
                                           queue_handler[pf]->data);
 
         read_unlock(&queue_handler_lock);
@@ -153,7 +153,7 @@ int nf_queue(struct sk_buff **skb,
 #endif
                 module_put(info->elem->owner);
                 kfree(info);
-                kfree_skb(*skb);
+                kfree_skb(skb);
 
                 return 1;
         }
@@ -161,6 +161,46 @@ int nf_queue(struct sk_buff **skb,
         return 1;
 }
 
+int nf_queue(struct sk_buff *skb,
+             struct list_head *elem,
+             int pf, unsigned int hook,
+             struct net_device *indev,
+             struct net_device *outdev,
+             int (*okfn)(struct sk_buff *),
+             unsigned int queuenum)
+{
+        struct sk_buff *segs;
+
+        if (!skb_is_gso(skb))
+                return __nf_queue(skb, elem, pf, hook, indev, outdev, okfn,
+                                  queuenum);
+
+        switch (pf) {
+        case AF_INET:
+                skb->protocol = htons(ETH_P_IP);
+                break;
+        case AF_INET6:
+                skb->protocol = htons(ETH_P_IPV6);
+                break;
+        }
+
+        segs = skb_gso_segment(skb, 0);
+        kfree_skb(skb);
+        if (unlikely(IS_ERR(segs)))
+                return 1;
+
+        do {
+                struct sk_buff *nskb = segs->next;
+
+                segs->next = NULL;
+                if (!__nf_queue(segs, elem, pf, hook, indev, outdev, okfn,
+                                queuenum))
+                        kfree_skb(segs);
+                segs = nskb;
+        } while (segs);
+        return 1;
+}
+
 void nf_reinject(struct sk_buff *skb, struct nf_info *info,
                  unsigned int verdict)
 {
@@ -224,9 +264,9 @@ void nf_reinject(struct sk_buff *skb, struct nf_info *info,
         case NF_STOLEN:
                 break;
         case NF_QUEUE:
-                if (!nf_queue(&skb, elem, info->pf, info->hook, 
-                              info->indev, info->outdev, info->okfn,
-                              verdict >> NF_VERDICT_BITS))
+                if (!__nf_queue(skb, elem, info->pf, info->hook,
+                                info->indev, info->outdev, info->okfn,
+                                verdict >> NF_VERDICT_BITS))
                         goto next_hook;
                 break;
         default: