From 01886bd91f1ba418ce669dfe97a06ca9504e482a Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Thu, 3 Nov 2016 10:56:35 +0100 Subject: [PATCH] netfilter: remove hook_entries field from nf_hook_state This field is only useful for nf_queue, so store it in the nf_queue_entry structure instead, away from the core path. Pass hook_head to nf_hook_slow(). Since we always have a valid entry on the first iteration in nf_iterate(), we can use 'do { ... } while (entry)' loop instead. Signed-off-by: Pablo Neira Ayuso --- include/linux/netfilter.h | 10 ++++------ include/linux/netfilter_ingress.h | 4 ++-- include/net/netfilter/nf_queue.h | 1 + net/bridge/br_netfilter_hooks.c | 4 ++-- net/bridge/netfilter/ebtable_broute.c | 2 +- net/netfilter/core.c | 9 ++++----- net/netfilter/nf_queue.c | 13 +++++-------- net/netfilter/nfnetlink_queue.c | 2 +- 8 files changed, 20 insertions(+), 25 deletions(-) diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h index e0d000f6c9bf..69230140215b 100644 --- a/include/linux/netfilter.h +++ b/include/linux/netfilter.h @@ -54,7 +54,6 @@ struct nf_hook_state { struct net_device *out; struct sock *sk; struct net *net; - struct nf_hook_entry __rcu *hook_entries; int (*okfn)(struct net *, struct sock *, struct sk_buff *); }; @@ -81,7 +80,6 @@ struct nf_hook_entry { }; static inline void nf_hook_state_init(struct nf_hook_state *p, - struct nf_hook_entry *hook_entry, unsigned int hook, u_int8_t pf, struct net_device *indev, @@ -96,7 +94,6 @@ static inline void nf_hook_state_init(struct nf_hook_state *p, p->out = outdev; p->sk = sk; p->net = net; - RCU_INIT_POINTER(p->hook_entries, hook_entry); p->okfn = okfn; } @@ -150,7 +147,8 @@ void nf_unregister_sockopt(struct nf_sockopt_ops *reg); extern struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS]; #endif -int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state); +int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state, + struct nf_hook_entry *entry); /** * nf_hook - call a netfilter hook @@ -179,10 +177,10 @@ static inline int nf_hook(u_int8_t pf, unsigned int hook, struct net *net, if (hook_head) { struct nf_hook_state state; - nf_hook_state_init(&state, hook_head, hook, pf, indev, outdev, + nf_hook_state_init(&state, hook, pf, indev, outdev, sk, net, okfn); - ret = nf_hook_slow(skb, &state); + ret = nf_hook_slow(skb, &state, hook_head); } rcu_read_unlock(); diff --git a/include/linux/netfilter_ingress.h b/include/linux/netfilter_ingress.h index fd44e4131710..2dc3b49b804a 100644 --- a/include/linux/netfilter_ingress.h +++ b/include/linux/netfilter_ingress.h @@ -26,10 +26,10 @@ static inline int nf_hook_ingress(struct sk_buff *skb) if (unlikely(!e)) return 0; - nf_hook_state_init(&state, e, NF_NETDEV_INGRESS, + nf_hook_state_init(&state, NF_NETDEV_INGRESS, NFPROTO_NETDEV, skb->dev, NULL, NULL, dev_net(skb->dev), NULL); - return nf_hook_slow(skb, &state); + return nf_hook_slow(skb, &state, e); } static inline void nf_hook_ingress_init(struct net_device *dev) diff --git a/include/net/netfilter/nf_queue.h b/include/net/netfilter/nf_queue.h index 2280cfe86c56..09948d10e38e 100644 --- a/include/net/netfilter/nf_queue.h +++ b/include/net/netfilter/nf_queue.h @@ -12,6 +12,7 @@ struct nf_queue_entry { unsigned int id; struct nf_hook_state state; + struct nf_hook_entry *hook; u16 size; /* sizeof(entry) + saved route keys */ /* extra space to store route keys */ diff --git a/net/bridge/br_netfilter_hooks.c b/net/bridge/br_netfilter_hooks.c index 7e3645fa6339..8155bd2a5138 100644 --- a/net/bridge/br_netfilter_hooks.c +++ b/net/bridge/br_netfilter_hooks.c @@ -1018,10 +1018,10 @@ int br_nf_hook_thresh(unsigned int hook, struct net *net, /* We may already have this, but read-locks nest anyway */ rcu_read_lock(); - nf_hook_state_init(&state, elem, hook, NFPROTO_BRIDGE, indev, outdev, + nf_hook_state_init(&state, hook, NFPROTO_BRIDGE, indev, outdev, sk, net, okfn); - ret = nf_hook_slow(skb, &state); + ret = nf_hook_slow(skb, &state, elem); rcu_read_unlock(); if (ret == 1) ret = okfn(net, sk, skb); diff --git a/net/bridge/netfilter/ebtable_broute.c b/net/bridge/netfilter/ebtable_broute.c index 599679e3498d..8fe36dc3aab2 100644 --- a/net/bridge/netfilter/ebtable_broute.c +++ b/net/bridge/netfilter/ebtable_broute.c @@ -53,7 +53,7 @@ static int ebt_broute(struct sk_buff *skb) struct nf_hook_state state; int ret; - nf_hook_state_init(&state, NULL, NF_BR_BROUTING, + nf_hook_state_init(&state, NF_BR_BROUTING, NFPROTO_BRIDGE, skb->dev, NULL, NULL, dev_net(skb->dev), NULL); diff --git a/net/netfilter/core.c b/net/netfilter/core.c index 64623374bc5f..ebece48b8392 100644 --- a/net/netfilter/core.c +++ b/net/netfilter/core.c @@ -308,7 +308,7 @@ unsigned int nf_iterate(struct sk_buff *skb, { unsigned int verdict; - while (*entryp) { + do { repeat: verdict = (*entryp)->ops.hook((*entryp)->ops.priv, skb, state); if (verdict != NF_ACCEPT) { @@ -317,20 +317,19 @@ repeat: goto repeat; } *entryp = rcu_dereference((*entryp)->next); - } + } while (*entryp); return NF_ACCEPT; } /* Returns 1 if okfn() needs to be executed by the caller, * -EPERM for NF_DROP, 0 otherwise. Caller must hold rcu_read_lock. */ -int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state) +int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state, + struct nf_hook_entry *entry) { - struct nf_hook_entry *entry; unsigned int verdict; int ret; - entry = rcu_dereference(state->hook_entries); next_hook: verdict = nf_iterate(skb, state, &entry); switch (verdict & NF_VERDICT_MASK) { diff --git a/net/netfilter/nf_queue.c b/net/netfilter/nf_queue.c index 0fb38966e5bf..2e39e38ae1c7 100644 --- a/net/netfilter/nf_queue.c +++ b/net/netfilter/nf_queue.c @@ -108,7 +108,7 @@ void nf_queue_nf_hook_drop(struct net *net, const struct nf_hook_entry *entry) } static int __nf_queue(struct sk_buff *skb, const struct nf_hook_state *state, - unsigned int queuenum) + struct nf_hook_entry *hook_entry, unsigned int queuenum) { int status = -ENOENT; struct nf_queue_entry *entry = NULL; @@ -136,6 +136,7 @@ static int __nf_queue(struct sk_buff *skb, const struct nf_hook_state *state, *entry = (struct nf_queue_entry) { .skb = skb, .state = *state, + .hook = hook_entry, .size = sizeof(*entry) + afinfo->route_key_size, }; @@ -163,8 +164,7 @@ int nf_queue(struct sk_buff *skb, struct nf_hook_state *state, struct nf_hook_entry *entry = *entryp; int ret; - RCU_INIT_POINTER(state->hook_entries, entry); - ret = __nf_queue(skb, state, verdict >> NF_VERDICT_QBITS); + ret = __nf_queue(skb, state, entry, verdict >> NF_VERDICT_QBITS); if (ret < 0) { if (ret == -ESRCH && (verdict & NF_VERDICT_FLAG_QUEUE_BYPASS)) { @@ -179,15 +179,12 @@ int nf_queue(struct sk_buff *skb, struct nf_hook_state *state, void nf_reinject(struct nf_queue_entry *entry, unsigned int verdict) { - struct nf_hook_entry *hook_entry; + struct nf_hook_entry *hook_entry = entry->hook; + struct nf_hook_ops *elem = &hook_entry->ops; struct sk_buff *skb = entry->skb; const struct nf_afinfo *afinfo; - struct nf_hook_ops *elem; int err; - hook_entry = rcu_dereference(entry->state.hook_entries); - elem = &hook_entry->ops; - nf_queue_entry_release_refs(entry); /* Continue traversal iff userspace said ok... */ diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c index 5379f788a372..1e33115b399f 100644 --- a/net/netfilter/nfnetlink_queue.c +++ b/net/netfilter/nfnetlink_queue.c @@ -919,7 +919,7 @@ static struct notifier_block nfqnl_dev_notifier = { static int nf_hook_cmp(struct nf_queue_entry *entry, unsigned long entry_ptr) { - return rcu_access_pointer(entry->state.hook_entries) == + return rcu_access_pointer(entry->hook) == (struct nf_hook_entry *)entry_ptr; } -- 2.30.2