From a685e08987d1edf1995b76511d4c98ea0e905377 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Wed, 8 Jun 2011 21:13:01 -0400 Subject: Delay struct net freeing while there's a sysfs instance refering to it * new refcount in struct net, controlling actual freeing of the memory * new method in kobj_ns_type_operations (->drop_ns()) * ->current_ns() semantics change - it's supposed to be followed by corresponding ->drop_ns(). For struct net in case of CONFIG_NET_NS it bumps the new refcount; net_drop_ns() decrements it and calls net_free() if the last reference has been dropped. Method renamed to ->grab_current_ns(). * old net_free() callers call net_drop_ns() instead. * sysfs_exit_ns() is gone, along with a large part of callchain leading to it; now that the references stored in ->ns[...] stay valid we do not need to hunt them down and replace them with NULL. That fixes problems in sysfs_lookup() and sysfs_readdir(), along with getting rid of sb->s_instances abuse. Note that struct net *shutdown* logics has not changed - net_cleanup() is called exactly when it used to be called. The only thing postponed by having a sysfs instance refering to that struct net is actual freeing of memory occupied by struct net. Signed-off-by: Al Viro --- include/net/net_namespace.h | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'include/net') diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 2bf9ed9ef26..aef430d779b 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -35,8 +35,11 @@ struct netns_ipvs; #define NETDEV_HASHENTRIES (1 << NETDEV_HASHBITS) struct net { + atomic_t passive; /* To decided when the network + * namespace should be freed. + */ atomic_t count; /* To decided when the network - * namespace should be freed. + * namespace should be shut down. */ #ifdef NETNS_REFCNT_DEBUG atomic_t use_count; /* To track references we @@ -154,6 +157,9 @@ int net_eq(const struct net *net1, const struct net *net2) { return net1 == net2; } + +extern void net_drop_ns(void *); + #else static inline struct net *get_net(struct net *net) @@ -175,6 +181,8 @@ int net_eq(const struct net *net1, const struct net *net2) { return 1; } + +#define net_drop_ns NULL #endif -- cgit v1.2.3-70-g09d2 From 42c1edd345c8412d96e7a362ee06feb7be73bb6c Mon Sep 17 00:00:00 2001 From: Julian Anastasov Date: Thu, 16 Jun 2011 17:29:22 +0200 Subject: netfilter: nf_nat: avoid double seq_adjust for loopback Avoid double seq adjustment for loopback traffic because it causes silent repetition of TCP data. One example is passive FTP with DNAT rule and difference in the length of IP addresses. This patch adds check if packet is sent and received via loopback device. As the same conntrack is used both for outgoing and incoming direction, we restrict seq adjustment to happen only in POSTROUTING. Signed-off-by: Julian Anastasov Signed-off-by: Patrick McHardy --- include/net/netfilter/nf_conntrack.h | 6 ++++++ net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c | 4 +++- 2 files changed, 9 insertions(+), 1 deletion(-) (limited to 'include/net') diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h index c7c42e7acc3..5d4f8e586e3 100644 --- a/include/net/netfilter/nf_conntrack.h +++ b/include/net/netfilter/nf_conntrack.h @@ -307,6 +307,12 @@ static inline int nf_ct_is_untracked(const struct nf_conn *ct) return test_bit(IPS_UNTRACKED_BIT, &ct->status); } +/* Packet is received from loopback */ +static inline bool nf_is_loopback_packet(const struct sk_buff *skb) +{ + return skb->dev && skb->skb_iif && skb->dev->flags & IFF_LOOPBACK; +} + extern int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp); extern unsigned int nf_conntrack_htable_size; extern unsigned int nf_conntrack_max; diff --git a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c index db10075dd88..de9da21113a 100644 --- a/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c +++ b/net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c @@ -121,7 +121,9 @@ static unsigned int ipv4_confirm(unsigned int hooknum, return ret; } - if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status)) { + /* adjust seqs for loopback traffic only in outgoing direction */ + if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && + !nf_is_loopback_packet(skb)) { typeof(nf_nat_seq_adjust_hook) seq_adjust; seq_adjust = rcu_dereference(nf_nat_seq_adjust_hook); -- cgit v1.2.3-70-g09d2