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Diffstat (limited to 'net/xfrm/xfrm_policy.c')
-rw-r--r--net/xfrm/xfrm_policy.c145
1 files changed, 86 insertions, 59 deletions
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index b5e665b3cfb0..f7ce6265961a 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -49,6 +49,7 @@ static struct xfrm_policy_afinfo __rcu *xfrm_policy_afinfo[NPROTO]
__read_mostly;
static struct kmem_cache *xfrm_dst_cache __read_mostly;
+static __read_mostly seqcount_t xfrm_policy_hash_generation;
static void xfrm_init_pmtu(struct dst_entry *dst);
static int stale_bundle(struct dst_entry *dst);
@@ -59,6 +60,11 @@ static void __xfrm_policy_link(struct xfrm_policy *pol, int dir);
static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
int dir);
+static inline bool xfrm_pol_hold_rcu(struct xfrm_policy *policy)
+{
+ return atomic_inc_not_zero(&policy->refcnt);
+}
+
static inline bool
__xfrm4_selector_match(const struct xfrm_selector *sel, const struct flowi *fl)
{
@@ -385,9 +391,11 @@ static struct hlist_head *policy_hash_bysel(struct net *net,
__get_hash_thresh(net, family, dir, &dbits, &sbits);
hash = __sel_hash(sel, family, hmask, dbits, sbits);
- return (hash == hmask + 1 ?
- &net->xfrm.policy_inexact[dir] :
- net->xfrm.policy_bydst[dir].table + hash);
+ if (hash == hmask + 1)
+ return &net->xfrm.policy_inexact[dir];
+
+ return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
+ lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
}
static struct hlist_head *policy_hash_direct(struct net *net,
@@ -403,7 +411,8 @@ static struct hlist_head *policy_hash_direct(struct net *net,
__get_hash_thresh(net, family, dir, &dbits, &sbits);
hash = __addr_hash(daddr, saddr, family, hmask, dbits, sbits);
- return net->xfrm.policy_bydst[dir].table + hash;
+ return rcu_dereference_check(net->xfrm.policy_bydst[dir].table,
+ lockdep_is_held(&net->xfrm.xfrm_policy_lock)) + hash;
}
static void xfrm_dst_hash_transfer(struct net *net,
@@ -426,14 +435,14 @@ redo:
h = __addr_hash(&pol->selector.daddr, &pol->selector.saddr,
pol->family, nhashmask, dbits, sbits);
if (!entry0) {
- hlist_del(&pol->bydst);
- hlist_add_head(&pol->bydst, ndsttable+h);
+ hlist_del_rcu(&pol->bydst);
+ hlist_add_head_rcu(&pol->bydst, ndsttable + h);
h0 = h;
} else {
if (h != h0)
continue;
- hlist_del(&pol->bydst);
- hlist_add_behind(&pol->bydst, entry0);
+ hlist_del_rcu(&pol->bydst);
+ hlist_add_behind_rcu(&pol->bydst, entry0);
}
entry0 = &pol->bydst;
}
@@ -468,22 +477,32 @@ static void xfrm_bydst_resize(struct net *net, int dir)
unsigned int hmask = net->xfrm.policy_bydst[dir].hmask;
unsigned int nhashmask = xfrm_new_hash_mask(hmask);
unsigned int nsize = (nhashmask + 1) * sizeof(struct hlist_head);
- struct hlist_head *odst = net->xfrm.policy_bydst[dir].table;
struct hlist_head *ndst = xfrm_hash_alloc(nsize);
+ struct hlist_head *odst;
int i;
if (!ndst)
return;
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
+ write_seqcount_begin(&xfrm_policy_hash_generation);
+
+ odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
+ lockdep_is_held(&net->xfrm.xfrm_policy_lock));
+
+ odst = rcu_dereference_protected(net->xfrm.policy_bydst[dir].table,
+ lockdep_is_held(&net->xfrm.xfrm_policy_lock));
for (i = hmask; i >= 0; i--)
xfrm_dst_hash_transfer(net, odst + i, ndst, nhashmask, dir);
- net->xfrm.policy_bydst[dir].table = ndst;
+ rcu_assign_pointer(net->xfrm.policy_bydst[dir].table, ndst);
net->xfrm.policy_bydst[dir].hmask = nhashmask;
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ write_seqcount_end(&xfrm_policy_hash_generation);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
+
+ synchronize_rcu();
xfrm_hash_free(odst, (hmask + 1) * sizeof(struct hlist_head));
}
@@ -500,7 +519,7 @@ static void xfrm_byidx_resize(struct net *net, int total)
if (!nidx)
return;
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
for (i = hmask; i >= 0; i--)
xfrm_idx_hash_transfer(oidx + i, nidx, nhashmask);
@@ -508,7 +527,7 @@ static void xfrm_byidx_resize(struct net *net, int total)
net->xfrm.policy_byidx = nidx;
net->xfrm.policy_idx_hmask = nhashmask;
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
xfrm_hash_free(oidx, (hmask + 1) * sizeof(struct hlist_head));
}
@@ -541,7 +560,6 @@ static inline int xfrm_byidx_should_resize(struct net *net, int total)
void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
{
- read_lock_bh(&net->xfrm.xfrm_policy_lock);
si->incnt = net->xfrm.policy_count[XFRM_POLICY_IN];
si->outcnt = net->xfrm.policy_count[XFRM_POLICY_OUT];
si->fwdcnt = net->xfrm.policy_count[XFRM_POLICY_FWD];
@@ -550,7 +568,6 @@ void xfrm_spd_getinfo(struct net *net, struct xfrmk_spdinfo *si)
si->fwdscnt = net->xfrm.policy_count[XFRM_POLICY_FWD+XFRM_POLICY_MAX];
si->spdhcnt = net->xfrm.policy_idx_hmask;
si->spdhmcnt = xfrm_policy_hashmax;
- read_unlock_bh(&net->xfrm.xfrm_policy_lock);
}
EXPORT_SYMBOL(xfrm_spd_getinfo);
@@ -600,7 +617,7 @@ static void xfrm_hash_rebuild(struct work_struct *work)
rbits6 = net->xfrm.policy_hthresh.rbits6;
} while (read_seqretry(&net->xfrm.policy_hthresh.lock, seq));
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
/* reset the bydst and inexact table in all directions */
for (dir = 0; dir < XFRM_POLICY_MAX; dir++) {
@@ -642,7 +659,7 @@ static void xfrm_hash_rebuild(struct work_struct *work)
hlist_add_head(&policy->bydst, chain);
}
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
mutex_unlock(&hash_resize_mutex);
}
@@ -753,7 +770,7 @@ int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
struct hlist_head *chain;
struct hlist_node *newpos;
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
chain = policy_hash_bysel(net, &policy->selector, policy->family, dir);
delpol = NULL;
newpos = NULL;
@@ -764,7 +781,7 @@ int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
xfrm_sec_ctx_match(pol->security, policy->security) &&
!WARN_ON(delpol)) {
if (excl) {
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return -EEXIST;
}
delpol = pol;
@@ -800,7 +817,7 @@ int xfrm_policy_insert(int dir, struct xfrm_policy *policy, int excl)
policy->curlft.use_time = 0;
if (!mod_timer(&policy->timer, jiffies + HZ))
xfrm_pol_hold(policy);
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
if (delpol)
xfrm_policy_kill(delpol);
@@ -820,7 +837,7 @@ struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
struct hlist_head *chain;
*err = 0;
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
chain = policy_hash_bysel(net, sel, sel->family, dir);
ret = NULL;
hlist_for_each_entry(pol, chain, bydst) {
@@ -833,7 +850,7 @@ struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
*err = security_xfrm_policy_delete(
pol->security);
if (*err) {
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return pol;
}
__xfrm_policy_unlink(pol, dir);
@@ -842,7 +859,7 @@ struct xfrm_policy *xfrm_policy_bysel_ctx(struct net *net, u32 mark, u8 type,
break;
}
}
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
if (ret && delete)
xfrm_policy_kill(ret);
@@ -861,7 +878,7 @@ struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
return NULL;
*err = 0;
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
chain = net->xfrm.policy_byidx + idx_hash(net, id);
ret = NULL;
hlist_for_each_entry(pol, chain, byidx) {
@@ -872,7 +889,7 @@ struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
*err = security_xfrm_policy_delete(
pol->security);
if (*err) {
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return pol;
}
__xfrm_policy_unlink(pol, dir);
@@ -881,7 +898,7 @@ struct xfrm_policy *xfrm_policy_byid(struct net *net, u32 mark, u8 type,
break;
}
}
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
if (ret && delete)
xfrm_policy_kill(ret);
@@ -939,7 +956,7 @@ int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
{
int dir, err = 0, cnt = 0;
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
err = xfrm_policy_flush_secctx_check(net, type, task_valid);
if (err)
@@ -955,14 +972,14 @@ int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
if (pol->type != type)
continue;
__xfrm_policy_unlink(pol, dir);
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
cnt++;
xfrm_audit_policy_delete(pol, 1, task_valid);
xfrm_policy_kill(pol);
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
goto again1;
}
@@ -974,13 +991,13 @@ int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
if (pol->type != type)
continue;
__xfrm_policy_unlink(pol, dir);
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
cnt++;
xfrm_audit_policy_delete(pol, 1, task_valid);
xfrm_policy_kill(pol);
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
goto again2;
}
}
@@ -989,7 +1006,7 @@ int xfrm_policy_flush(struct net *net, u8 type, bool task_valid)
if (!cnt)
err = -ESRCH;
out:
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return err;
}
EXPORT_SYMBOL(xfrm_policy_flush);
@@ -1009,7 +1026,7 @@ int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
if (list_empty(&walk->walk.all) && walk->seq != 0)
return 0;
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
if (list_empty(&walk->walk.all))
x = list_first_entry(&net->xfrm.policy_all, struct xfrm_policy_walk_entry, all);
else
@@ -1037,7 +1054,7 @@ int xfrm_policy_walk(struct net *net, struct xfrm_policy_walk *walk,
}
list_del_init(&walk->walk.all);
out:
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return error;
}
EXPORT_SYMBOL(xfrm_policy_walk);
@@ -1056,9 +1073,9 @@ void xfrm_policy_walk_done(struct xfrm_policy_walk *walk, struct net *net)
if (list_empty(&walk->walk.all))
return;
- write_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME where is net? */
list_del(&walk->walk.all);
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
}
EXPORT_SYMBOL(xfrm_policy_walk_done);
@@ -1096,17 +1113,24 @@ static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
struct xfrm_policy *pol, *ret;
const xfrm_address_t *daddr, *saddr;
struct hlist_head *chain;
- u32 priority = ~0U;
+ unsigned int sequence;
+ u32 priority;
daddr = xfrm_flowi_daddr(fl, family);
saddr = xfrm_flowi_saddr(fl, family);
if (unlikely(!daddr || !saddr))
return NULL;
- read_lock_bh(&net->xfrm.xfrm_policy_lock);
- chain = policy_hash_direct(net, daddr, saddr, family, dir);
+ rcu_read_lock();
+ retry:
+ do {
+ sequence = read_seqcount_begin(&xfrm_policy_hash_generation);
+ chain = policy_hash_direct(net, daddr, saddr, family, dir);
+ } while (read_seqcount_retry(&xfrm_policy_hash_generation, sequence));
+
+ priority = ~0U;
ret = NULL;
- hlist_for_each_entry(pol, chain, bydst) {
+ hlist_for_each_entry_rcu(pol, chain, bydst) {
err = xfrm_policy_match(pol, fl, type, family, dir);
if (err) {
if (err == -ESRCH)
@@ -1122,7 +1146,7 @@ static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
}
}
chain = &net->xfrm.policy_inexact[dir];
- hlist_for_each_entry(pol, chain, bydst) {
+ hlist_for_each_entry_rcu(pol, chain, bydst) {
if ((pol->priority >= priority) && ret)
break;
@@ -1140,9 +1164,13 @@ static struct xfrm_policy *xfrm_policy_lookup_bytype(struct net *net, u8 type,
}
}
- xfrm_pol_hold(ret);
+ if (read_seqcount_retry(&xfrm_policy_hash_generation, sequence))
+ goto retry;
+
+ if (ret && !xfrm_pol_hold_rcu(ret))
+ goto retry;
fail:
- read_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ rcu_read_unlock();
return ret;
}
@@ -1219,10 +1247,9 @@ static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
const struct flowi *fl)
{
struct xfrm_policy *pol;
- struct net *net = sock_net(sk);
rcu_read_lock();
- read_lock_bh(&net->xfrm.xfrm_policy_lock);
+ again:
pol = rcu_dereference(sk->sk_policy[dir]);
if (pol != NULL) {
bool match = xfrm_selector_match(&pol->selector, fl,
@@ -1237,8 +1264,8 @@ static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
err = security_xfrm_policy_lookup(pol->security,
fl->flowi_secid,
policy_to_flow_dir(dir));
- if (!err)
- xfrm_pol_hold(pol);
+ if (!err && !xfrm_pol_hold_rcu(pol))
+ goto again;
else if (err == -ESRCH)
pol = NULL;
else
@@ -1247,7 +1274,6 @@ static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir,
pol = NULL;
}
out:
- read_unlock_bh(&net->xfrm.xfrm_policy_lock);
rcu_read_unlock();
return pol;
}
@@ -1271,7 +1297,7 @@ static struct xfrm_policy *__xfrm_policy_unlink(struct xfrm_policy *pol,
/* Socket policies are not hashed. */
if (!hlist_unhashed(&pol->bydst)) {
- hlist_del(&pol->bydst);
+ hlist_del_rcu(&pol->bydst);
hlist_del(&pol->byidx);
}
@@ -1295,9 +1321,9 @@ int xfrm_policy_delete(struct xfrm_policy *pol, int dir)
{
struct net *net = xp_net(pol);
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
pol = __xfrm_policy_unlink(pol, dir);
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
if (pol) {
xfrm_policy_kill(pol);
return 0;
@@ -1316,7 +1342,7 @@ int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
return -EINVAL;
#endif
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
old_pol = rcu_dereference_protected(sk->sk_policy[dir],
lockdep_is_held(&net->xfrm.xfrm_policy_lock));
if (pol) {
@@ -1334,7 +1360,7 @@ int xfrm_sk_policy_insert(struct sock *sk, int dir, struct xfrm_policy *pol)
*/
xfrm_sk_policy_unlink(old_pol, dir);
}
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
if (old_pol) {
xfrm_policy_kill(old_pol);
@@ -1364,9 +1390,9 @@ static struct xfrm_policy *clone_policy(const struct xfrm_policy *old, int dir)
newp->type = old->type;
memcpy(newp->xfrm_vec, old->xfrm_vec,
newp->xfrm_nr*sizeof(struct xfrm_tmpl));
- write_lock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
xfrm_sk_policy_link(newp, dir);
- write_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
xfrm_pol_put(newp);
}
return newp;
@@ -3048,7 +3074,7 @@ static int __net_init xfrm_net_init(struct net *net)
/* Initialize the per-net locks here */
spin_lock_init(&net->xfrm.xfrm_state_lock);
- rwlock_init(&net->xfrm.xfrm_policy_lock);
+ spin_lock_init(&net->xfrm.xfrm_policy_lock);
mutex_init(&net->xfrm.xfrm_cfg_mutex);
return 0;
@@ -3082,6 +3108,7 @@ static struct pernet_operations __net_initdata xfrm_net_ops = {
void __init xfrm_init(void)
{
register_pernet_subsys(&xfrm_net_ops);
+ seqcount_init(&xfrm_policy_hash_generation);
xfrm_input_init();
}
@@ -3179,7 +3206,7 @@ static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *
struct hlist_head *chain;
u32 priority = ~0U;
- read_lock_bh(&net->xfrm.xfrm_policy_lock); /*FIXME*/
+ spin_lock_bh(&net->xfrm.xfrm_policy_lock);
chain = policy_hash_direct(net, &sel->daddr, &sel->saddr, sel->family, dir);
hlist_for_each_entry(pol, chain, bydst) {
if (xfrm_migrate_selector_match(sel, &pol->selector) &&
@@ -3203,7 +3230,7 @@ static struct xfrm_policy *xfrm_migrate_policy_find(const struct xfrm_selector *
xfrm_pol_hold(ret);
- read_unlock_bh(&net->xfrm.xfrm_policy_lock);
+ spin_unlock_bh(&net->xfrm.xfrm_policy_lock);
return ret;
}
generated by cgit (git 2.34.1) at 2024-05-27 01:57:26 +0000