Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/net/sunrpc/svcauth.c b/net/sunrpc/svcauth.c
index bb8db3c..550b214 100644
--- a/net/sunrpc/svcauth.c
+++ b/net/sunrpc/svcauth.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/net/sunrpc/svcauth.c
*
@@ -27,12 +28,32 @@
extern struct auth_ops svcauth_null;
extern struct auth_ops svcauth_unix;
-static DEFINE_SPINLOCK(authtab_lock);
-static struct auth_ops *authtab[RPC_AUTH_MAXFLAVOR] = {
- [0] = &svcauth_null,
- [1] = &svcauth_unix,
+static struct auth_ops __rcu *authtab[RPC_AUTH_MAXFLAVOR] = {
+ [RPC_AUTH_NULL] = (struct auth_ops __force __rcu *)&svcauth_null,
+ [RPC_AUTH_UNIX] = (struct auth_ops __force __rcu *)&svcauth_unix,
};
+static struct auth_ops *
+svc_get_auth_ops(rpc_authflavor_t flavor)
+{
+ struct auth_ops *aops;
+
+ if (flavor >= RPC_AUTH_MAXFLAVOR)
+ return NULL;
+ rcu_read_lock();
+ aops = rcu_dereference(authtab[flavor]);
+ if (aops != NULL && !try_module_get(aops->owner))
+ aops = NULL;
+ rcu_read_unlock();
+ return aops;
+}
+
+static void
+svc_put_auth_ops(struct auth_ops *aops)
+{
+ module_put(aops->owner);
+}
+
int
svc_authenticate(struct svc_rqst *rqstp, __be32 *authp)
{
@@ -45,14 +66,11 @@
dprintk("svc: svc_authenticate (%d)\n", flavor);
- spin_lock(&authtab_lock);
- if (flavor >= RPC_AUTH_MAXFLAVOR || !(aops = authtab[flavor]) ||
- !try_module_get(aops->owner)) {
- spin_unlock(&authtab_lock);
+ aops = svc_get_auth_ops(flavor);
+ if (aops == NULL) {
*authp = rpc_autherr_badcred;
return SVC_DENIED;
}
- spin_unlock(&authtab_lock);
rqstp->rq_auth_slack = 0;
init_svc_cred(&rqstp->rq_cred);
@@ -82,7 +100,7 @@
if (aops) {
rv = aops->release(rqstp);
- module_put(aops->owner);
+ svc_put_auth_ops(aops);
}
return rv;
}
@@ -90,13 +108,14 @@
int
svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops)
{
+ struct auth_ops *old;
int rv = -EINVAL;
- spin_lock(&authtab_lock);
- if (flavor < RPC_AUTH_MAXFLAVOR && authtab[flavor] == NULL) {
- authtab[flavor] = aops;
- rv = 0;
+
+ if (flavor < RPC_AUTH_MAXFLAVOR) {
+ old = cmpxchg((struct auth_ops ** __force)&authtab[flavor], NULL, aops);
+ if (old == NULL || old == aops)
+ rv = 0;
}
- spin_unlock(&authtab_lock);
return rv;
}
EXPORT_SYMBOL_GPL(svc_auth_register);
@@ -104,10 +123,8 @@
void
svc_auth_unregister(rpc_authflavor_t flavor)
{
- spin_lock(&authtab_lock);
if (flavor < RPC_AUTH_MAXFLAVOR)
- authtab[flavor] = NULL;
- spin_unlock(&authtab_lock);
+ rcu_assign_pointer(authtab[flavor], NULL);
}
EXPORT_SYMBOL_GPL(svc_auth_unregister);
@@ -127,10 +144,11 @@
static DEFINE_SPINLOCK(auth_domain_lock);
static void auth_domain_release(struct kref *kref)
+ __releases(&auth_domain_lock)
{
struct auth_domain *dom = container_of(kref, struct auth_domain, ref);
- hlist_del(&dom->hash);
+ hlist_del_rcu(&dom->hash);
dom->flavour->domain_release(dom);
spin_unlock(&auth_domain_lock);
}
@@ -159,7 +177,7 @@
}
}
if (new)
- hlist_add_head(&new->hash, head);
+ hlist_add_head_rcu(&new->hash, head);
spin_unlock(&auth_domain_lock);
return new;
}
@@ -167,6 +185,21 @@
struct auth_domain *auth_domain_find(char *name)
{
- return auth_domain_lookup(name, NULL);
+ struct auth_domain *hp;
+ struct hlist_head *head;
+
+ head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(hp, head, hash) {
+ if (strcmp(hp->name, name)==0) {
+ if (!kref_get_unless_zero(&hp->ref))
+ hp = NULL;
+ rcu_read_unlock();
+ return hp;
+ }
+ }
+ rcu_read_unlock();
+ return NULL;
}
EXPORT_SYMBOL_GPL(auth_domain_find);