Revert "xfrm: Fix RCU vs hash_resize_mutex lock inversion"

This reverts commit f08b2d078c which is
commit 2580d3f40022642452dd8422bfb8c22e54cf84bb upstream.

It breaks the abi and should not be needed for Android systems.

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I13a6e3459cc2c7fb31b4cbc1185a9b463fc61c6e
This commit is contained in:
Greg Kroah-Hartman
2021-08-12 19:52:24 +02:00
parent af3bdb4304
commit c80c82c899
2 changed files with 9 additions and 9 deletions

View File

@@ -75,7 +75,6 @@ struct netns_xfrm {
#endif #endif
spinlock_t xfrm_state_lock; spinlock_t xfrm_state_lock;
seqcount_t xfrm_state_hash_generation; seqcount_t xfrm_state_hash_generation;
seqcount_spinlock_t xfrm_policy_hash_generation;
spinlock_t xfrm_policy_lock; spinlock_t xfrm_policy_lock;
struct mutex xfrm_cfg_mutex; struct mutex xfrm_cfg_mutex;

View File

@@ -155,6 +155,7 @@ static struct xfrm_policy_afinfo const __rcu *xfrm_policy_afinfo[AF_INET6 + 1]
__read_mostly; __read_mostly;
static struct kmem_cache *xfrm_dst_cache __ro_after_init; static struct kmem_cache *xfrm_dst_cache __ro_after_init;
static __read_mostly seqcount_mutex_t xfrm_policy_hash_generation;
static struct rhashtable xfrm_policy_inexact_table; static struct rhashtable xfrm_policy_inexact_table;
static const struct rhashtable_params xfrm_pol_inexact_params; static const struct rhashtable_params xfrm_pol_inexact_params;
@@ -584,7 +585,7 @@ static void xfrm_bydst_resize(struct net *net, int dir)
return; return;
spin_lock_bh(&net->xfrm.xfrm_policy_lock); spin_lock_bh(&net->xfrm.xfrm_policy_lock);
write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); write_seqcount_begin(&xfrm_policy_hash_generation);
odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table, odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
lockdep_is_held(&net->xfrm.xfrm_policy_lock)); lockdep_is_held(&net->xfrm.xfrm_policy_lock));
@@ -595,7 +596,7 @@ static void xfrm_bydst_resize(struct net *net, int dir)
rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst); rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
net->xfrm.policy_bydst[dir].hmask = nhashmask; net->xfrm.policy_bydst[dir].hmask = nhashmask;
write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); write_seqcount_end(&xfrm_policy_hash_generation);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock); spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
synchronize_rcu(); synchronize_rcu();
@@ -1244,7 +1245,7 @@ static void xfrm_hash_rebuild(struct work_struct *work)
} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq)); } while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
spin_lock_bh(&net->xfrm.xfrm_policy_lock); spin_lock_bh(&net->xfrm.xfrm_policy_lock);
write_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); write_seqcount_begin(&xfrm_policy_hash_generation);
/* make sure that we can insert the indirect policies again before /* make sure that we can insert the indirect policies again before
* we start with destructive action. * we start with destructive action.
@@ -1353,7 +1354,7 @@ static void xfrm_hash_rebuild(struct work_struct *work)
out_unlock: out_unlock:
__xfrm_policy_inexact_flush(net); __xfrm_policy_inexact_flush(net);
write_seqcount_end(&net->xfrm.xfrm_policy_hash_generation); write_seqcount_end(&xfrm_policy_hash_generation);
spin_unlock_bh(&net->xfrm.xfrm_policy_lock); spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
mutex_unlock(&hash_resize_mutex); mutex_unlock(&hash_resize_mutex);
@@ -2094,9 +2095,9 @@ static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
rcu_read_lock(); rcu_read_lock();
retry: retry:
do { do {
sequence = read_seqcount_begin(&net->xfrm.xfrm_policy_hash_generation); sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
chain = policy_hash_direct(net, daddr, saddr, family, dir); chain = policy_hash_direct(net, daddr, saddr, family, dir);
} while (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)); } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
ret = NULL; ret = NULL;
hlist_for_each_entry_rcu(pol, chain, bydst) { hlist_for_each_entry_rcu(pol, chain, bydst) {
@@ -2127,7 +2128,7 @@ static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
} }
skip_inexact: skip_inexact:
if (read_seqcount_retry(&net->xfrm.xfrm_policy_hash_generation, sequence)) if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
goto retry; goto retry;
if (ret && !xfrm_pol_hold_rcu(ret)) if (ret && !xfrm_pol_hold_rcu(ret))
@@ -4122,7 +4123,6 @@ static int __net_init xfrm_net_init(struct net *net)
/* Initialize the per-net locks here */ /* Initialize the per-net locks here */
spin_lock_init(&net->xfrm.xfrm_state_lock); spin_lock_init(&net->xfrm.xfrm_state_lock);
spin_lock_init(&net->xfrm.xfrm_policy_lock); spin_lock_init(&net->xfrm.xfrm_policy_lock);
seqcount_spinlock_init(&net->xfrm.xfrm_policy_hash_generation, &net->xfrm.xfrm_policy_lock);
mutex_init(&net->xfrm.xfrm_cfg_mutex); mutex_init(&net->xfrm.xfrm_cfg_mutex);
rv = xfrm_statistics_init(net); rv = xfrm_statistics_init(net);
@@ -4167,6 +4167,7 @@ void __init xfrm_init(void)
{ {
register_pernet_subsys(&xfrm_net_ops); register_pernet_subsys(&xfrm_net_ops);
xfrm_dev_init(); xfrm_dev_init();
seqcount_mutex_init(&xfrm_policy_hash_generation, &hash_resize_mutex);
xfrm_input_init(); xfrm_input_init();
#ifdef CONFIG_XFRM_ESPINTCP #ifdef CONFIG_XFRM_ESPINTCP