From 119e52e664c57d5f7c0174dc2b3a296b1e40591d Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Fri, 27 Mar 2020 03:24:47 +0100 Subject: netfilter: nf_queue: place bridge physports into queue_entry struct The refcount is done via entry->skb, which does work fine. Major problem: When putting the refcount of the bridge ports, we must always put the references while the skb is still around. However, we will need to put the references after okfn() to avoid a possible 1 -> 0 -> 1 refcount transition, so we cannot use the skb pointer anymore. Place the physports in the queue entry structure instead to allow for refcounting changes in the next patch. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_queue.c | 53 +++++++++++++++++++++--------------------------- 1 file changed, 23 insertions(+), 30 deletions(-) (limited to 'net/netfilter') diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c index 4da5776a9904..96eb72908467 100644 --- a/net/netfilter/nf_queue.c +++ b/net/netfilter/nf_queue.c @@ -46,24 +46,6 @@ void nf_unregister_queue_handler(struct net *net) } EXPORT_SYMBOL(nf_unregister_queue_handler); -static void nf_queue_entry_release_br_nf_refs(struct sk_buff *skb) -{ -#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) - struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb); - - if (nf_bridge) { - struct net_device *physdev; - - physdev = nf_bridge_get_physindev(skb); - if (physdev) - dev_put(physdev); - physdev = nf_bridge_get_physoutdev(skb); - if (physdev) - dev_put(physdev); - } -#endif -} - static void nf_queue_entry_release_refs(struct nf_queue_entry *entry) { struct nf_hook_state *state = &entry->state; @@ -76,7 +58,12 @@ static void nf_queue_entry_release_refs(struct nf_queue_entry *entry) if (state->sk) sock_put(state->sk); - nf_queue_entry_release_br_nf_refs(entry->skb); +#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) + if (entry->physin) + dev_put(entry->physin); + if (entry->physout) + dev_put(entry->physout); +#endif } void nf_queue_entry_free(struct nf_queue_entry *entry) @@ -86,20 +73,19 @@ void nf_queue_entry_free(struct nf_queue_entry *entry) } EXPORT_SYMBOL_GPL(nf_queue_entry_free); -static void nf_queue_entry_get_br_nf_refs(struct sk_buff *skb) +static void __nf_queue_entry_init_physdevs(struct nf_queue_entry *entry) { #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) - struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb); + const struct sk_buff *skb = entry->skb; + struct nf_bridge_info *nf_bridge; + nf_bridge = nf_bridge_info_get(skb); if (nf_bridge) { - struct net_device *physdev; - - physdev = nf_bridge_get_physindev(skb); - if (physdev) - dev_hold(physdev); - physdev = nf_bridge_get_physoutdev(skb); - if (physdev) - dev_hold(physdev); + entry->physin = nf_bridge_get_physindev(skb); + entry->physout = nf_bridge_get_physoutdev(skb); + } else { + entry->physin = NULL; + entry->physout = NULL; } #endif } @@ -116,7 +102,12 @@ void nf_queue_entry_get_refs(struct nf_queue_entry *entry) if (state->sk) sock_hold(state->sk); - nf_queue_entry_get_br_nf_refs(entry->skb); +#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER) + if (entry->physin) + dev_hold(entry->physin); + if (entry->physout) + dev_hold(entry->physout); +#endif } EXPORT_SYMBOL_GPL(nf_queue_entry_get_refs); @@ -207,6 +198,8 @@ static int __nf_queue(struct sk_buff *skb, const struct nf_hook_state *state, .size = sizeof(*entry) + route_key_size, }; + __nf_queue_entry_init_physdevs(entry); + nf_queue_entry_get_refs(entry); switch (entry->state.pf) { -- cgit v1.2.3