From 8201d923f492703a7d6c980cff3034759a452b86 Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Mon, 20 Jul 2020 17:55:20 +0200 Subject: netfilter: conntrack: Use sequence counter with associated spinlock A sequence counter write side critical section must be protected by some form of locking to serialize writers. A plain seqcount_t does not contain the information of which lock must be held when entering a write side critical section. Use the new seqcount_spinlock_t data type, which allows to associate a spinlock with the sequence counter. This enables lockdep to verify that the spinlock used for writer serialization is held when the write side critical section is entered. If lockdep is disabled this lock association is compiled out and has neither storage size nor runtime overhead. Signed-off-by: Ahmed S. Darwish Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20200720155530.1173732-15-a.darwish@linutronix.de --- net/netfilter/nf_conntrack_core.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index f33d72c5b06e..b597b5b16ba1 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -180,7 +180,7 @@ EXPORT_SYMBOL_GPL(nf_conntrack_htable_size); unsigned int nf_conntrack_max __read_mostly; EXPORT_SYMBOL_GPL(nf_conntrack_max); -seqcount_t nf_conntrack_generation __read_mostly; +seqcount_spinlock_t nf_conntrack_generation __read_mostly; static unsigned int nf_conntrack_hash_rnd __read_mostly; static u32 hash_conntrack_raw(const struct nf_conntrack_tuple *tuple, @@ -2600,7 +2600,8 @@ int nf_conntrack_init_start(void) /* struct nf_ct_ext uses u8 to store offsets/size */ BUILD_BUG_ON(total_extension_size() > 255u); - seqcount_init(&nf_conntrack_generation); + seqcount_spinlock_init(&nf_conntrack_generation, + &nf_conntrack_locks_all_lock); for (i = 0; i < CONNTRACK_LOCKS; i++) spin_lock_init(&nf_conntrack_locks[i]); -- cgit 1.4.1 From b901892b51317b321c7bc96e2ccd2f522d1380ee Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Mon, 20 Jul 2020 17:55:21 +0200 Subject: netfilter: nft_set_rbtree: Use sequence counter with associated rwlock A sequence counter write side critical section must be protected by some form of locking to serialize writers. A plain seqcount_t does not contain the information of which lock must be held when entering a write side critical section. Use the new seqcount_rwlock_t data type, which allows to associate a rwlock with the sequence counter. This enables lockdep to verify that the rwlock used for writer serialization is held when the write side critical section is entered. If lockdep is disabled this lock association is compiled out and has neither storage size nor runtime overhead. Signed-off-by: Ahmed S. Darwish Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20200720155530.1173732-16-a.darwish@linutronix.de --- net/netfilter/nft_set_rbtree.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'net') diff --git a/net/netfilter/nft_set_rbtree.c b/net/netfilter/nft_set_rbtree.c index b6aad3fc46c3..4b2834fd17b2 100644 --- a/net/netfilter/nft_set_rbtree.c +++ b/net/netfilter/nft_set_rbtree.c @@ -18,7 +18,7 @@ struct nft_rbtree { struct rb_root root; rwlock_t lock; - seqcount_t count; + seqcount_rwlock_t count; struct delayed_work gc_work; }; @@ -523,7 +523,7 @@ static int nft_rbtree_init(const struct nft_set *set, struct nft_rbtree *priv = nft_set_priv(set); rwlock_init(&priv->lock); - seqcount_init(&priv->count); + seqcount_rwlock_init(&priv->count, &priv->lock); priv->root = RB_ROOT; INIT_DEFERRABLE_WORK(&priv->gc_work, nft_rbtree_gc); -- cgit 1.4.1 From 77cc278f7b202e4f16f8596837219d02cb090b96 Mon Sep 17 00:00:00 2001 From: "Ahmed S. Darwish" Date: Mon, 20 Jul 2020 17:55:22 +0200 Subject: xfrm: policy: Use sequence counters with associated lock A sequence counter write side critical section must be protected by some form of locking to serialize writers. If the serialization primitive is not disabling preemption implicitly, preemption has to be explicitly disabled before entering the sequence counter write side critical section. A plain seqcount_t does not contain the information of which lock must be held when entering a write side critical section. Use the new seqcount_spinlock_t and seqcount_mutex_t data types instead, which allow to associate a lock with the sequence counter. This enables lockdep to verify that the lock used for writer serialization is held when the write side critical section is entered. If lockdep is disabled this lock association is compiled out and has neither storage size nor runtime overhead. Signed-off-by: Ahmed S. Darwish Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20200720155530.1173732-17-a.darwish@linutronix.de --- net/xfrm/xfrm_policy.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'net') diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index 564aa6492e7c..732a940468b0 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -122,7 +122,7 @@ struct xfrm_pol_inexact_bin { /* list containing '*:*' policies */ struct hlist_head hhead; - seqcount_t count; + seqcount_spinlock_t count; /* tree sorted by daddr/prefix */ struct rb_root root_d; @@ -155,7 +155,7 @@ static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1] __read_mostly; static struct kmem_cache *xfrm_dst_cache __ro_after_init; -static __read_mostly seqcount_t xfrm_policy_hash_generation; +static __read_mostly seqcount_mutex_t xfrm_policy_hash_generation; static struct rhashtable xfrm_policy_inexact_table; static const struct rhashtable_params xfrm_pol_inexact_params; @@ -719,7 +719,7 @@ xfrm_policy_inexact_alloc_bin(const struct xfrm_policy *pol, u8 dir) INIT_HLIST_HEAD(&bin->hhead); bin->root_d = RB_ROOT; bin->root_s = RB_ROOT; - seqcount_init(&bin->count); + seqcount_spinlock_init(&bin->count, &net->xfrm.xfrm_policy_lock); prev = rhashtable_lookup_get_insert_key(&xfrm_policy_inexact_table, &bin->k, &bin->head, @@ -1906,7 +1906,7 @@ static int xfrm_policy_match(const struct xfrm_policy *pol, static struct xfrm_pol_inexact_node * xfrm_policy_lookup_inexact_addr(const struct rb_root *r, - seqcount_t *count, + seqcount_spinlock_t *count, const xfrm_address_t *addr, u16 family) { const struct rb_node *parent; @@ -4153,7 +4153,7 @@ void __init xfrm_init(void) { register_pernet_subsys(&xfrm_net_ops); xfrm_dev_init(); - seqcount_init(&xfrm_policy_hash_generation); + seqcount_mutex_init(&xfrm_policy_hash_generation, &hash_resize_mutex); xfrm_input_init(); #ifdef CONFIG_INET_ESPINTCP -- cgit 1.4.1