8 files changed, 68 insertions, 17 deletions

diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c
index 41144f71d615..2d1bb8af7696 100644
--- a/security/keys/encrypted-keys/encrypted.c
+++ b/security/keys/encrypted-keys/encrypted.c
@@ -314,7 +314,7 @@ static struct key *request_user_key(const char *master_desc, u8 **master_key,
 		goto error;
 
 	down_read(&ukey->sem);
-	upayload = rcu_dereference(ukey->payload.data);
+	upayload = ukey->payload.data;
 	*master_key = upayload->data;
 	*master_keylen = upayload->datalen;
 error:
@@ -810,7 +810,7 @@ static int encrypted_instantiate(struct key *key, const void *data,
 		goto out;
 	}
 
-	rcu_assign_pointer(key->payload.data, epayload);
+	rcu_assign_keypointer(key, epayload);
 out:
 	kfree(datablob);
 	return ret;
@@ -874,7 +874,7 @@ static int encrypted_update(struct key *key, const void *data, size_t datalen)
 	memcpy(new_epayload->payload_data, epayload->payload_data,
 	       epayload->payload_datalen);
 
-	rcu_assign_pointer(key->payload.data, new_epayload);
+	rcu_assign_keypointer(key, new_epayload);
 	call_rcu(&epayload->rcu, encrypted_rcu_free);
 out:
 	kfree(buf);
diff --git a/security/keys/encrypted-keys/masterkey_trusted.c b/security/keys/encrypted-keys/masterkey_trusted.c
index df87272e3f51..013f7e5d3a2f 100644
--- a/security/keys/encrypted-keys/masterkey_trusted.c
+++ b/security/keys/encrypted-keys/masterkey_trusted.c
@@ -18,6 +18,8 @@
 #include <linux/module.h>
 #include <linux/err.h>
 #include <keys/trusted-type.h>
+#include <keys/encrypted-type.h>
+#include "encrypted.h"
 
 /*
  * request_trusted_key - request the trusted key
@@ -37,7 +39,7 @@ struct key *request_trusted_key(const char *trusted_desc,
 		goto error;
 
 	down_read(&tkey->sem);
-	tpayload = rcu_dereference(tkey->payload.data);
+	tpayload = tkey->payload.data;
 	*master_key = tpayload->key;
 	*master_keylen = tpayload->key_len;
 error:
diff --git a/security/keys/gc.c b/security/keys/gc.c
index bf4d8da5a795..a42b45531aac 100644
--- a/security/keys/gc.c
+++ b/security/keys/gc.c
@@ -145,7 +145,9 @@ static void key_gc_keyring(struct key *keyring, time_t limit)
 	if (!klist)
 		goto unlock_dont_gc;
 
-	for (loop = klist->nkeys - 1; loop >= 0; loop--) {
+	loop = klist->nkeys;
+	smp_rmb();
+	for (loop--; loop >= 0; loop--) {
 		key = klist->keys[loop];
 		if (test_bit(KEY_FLAG_DEAD, &key->flags) ||
 		    (key->expiry > 0 && key->expiry <= limit))
diff --git a/security/keys/internal.h b/security/keys/internal.h
index c7a7caec4830..65647f825584 100644
--- a/security/keys/internal.h
+++ b/security/keys/internal.h
@@ -33,6 +33,7 @@
 
 extern struct key_type key_type_dead;
 extern struct key_type key_type_user;
+extern struct key_type key_type_logon;
 
 /*****************************************************************************/
 /*
diff --git a/security/keys/key.c b/security/keys/key.c
index 4f64c7267afb..7ada8019be1f 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -999,6 +999,7 @@ void __init key_init(void)
 	list_add_tail(&key_type_keyring.link, &key_types_list);
 	list_add_tail(&key_type_dead.link, &key_types_list);
 	list_add_tail(&key_type_user.link, &key_types_list);
+	list_add_tail(&key_type_logon.link, &key_types_list);
 
 	/* record the root user tracking */
 	rb_link_node(&root_key_user.node,
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index 37a7f3b28852..d605f75292e4 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -319,7 +319,7 @@ key_ref_t keyring_search_aux(key_ref_t keyring_ref,
 	struct key *keyring, *key;
 	key_ref_t key_ref;
 	long err;
-	int sp, kix;
+	int sp, nkeys, kix;
 
 	keyring = key_ref_to_ptr(keyring_ref);
 	possessed = is_key_possessed(keyring_ref);
@@ -380,7 +380,9 @@ descend:
 		goto not_this_keyring;
 
 	/* iterate through the keys in this keyring first */
-	for (kix = 0; kix < keylist->nkeys; kix++) {
+	nkeys = keylist->nkeys;
+	smp_rmb();
+	for (kix = 0; kix < nkeys; kix++) {
 		key = keylist->keys[kix];
 		kflags = key->flags;
 
@@ -421,7 +423,9 @@ descend:
 	/* search through the keyrings nested in this one */
 	kix = 0;
 ascend:
-	for (; kix < keylist->nkeys; kix++) {
+	nkeys = keylist->nkeys;
+	smp_rmb();
+	for (; kix < nkeys; kix++) {
 		key = keylist->keys[kix];
 		if (key->type != &key_type_keyring)
 			continue;
@@ -515,7 +519,7 @@ key_ref_t __keyring_search_one(key_ref_t keyring_ref,
 	struct keyring_list *klist;
 	unsigned long possessed;
 	struct key *keyring, *key;
-	int loop;
+	int nkeys, loop;
 
 	keyring = key_ref_to_ptr(keyring_ref);
 	possessed = is_key_possessed(keyring_ref);
@@ -524,7 +528,9 @@ key_ref_t __keyring_search_one(key_ref_t keyring_ref,
 
 	klist = rcu_dereference(keyring->payload.subscriptions);
 	if (klist) {
-		for (loop = 0; loop < klist->nkeys; loop++) {
+		nkeys = klist->nkeys;
+		smp_rmb();
+		for (loop = 0; loop < nkeys ; loop++) {
 			key = klist->keys[loop];
 
 			if (key->type == ktype &&
@@ -622,7 +628,7 @@ static int keyring_detect_cycle(struct key *A, struct key *B)
 
 	struct keyring_list *keylist;
 	struct key *subtree, *key;
-	int sp, kix, ret;
+	int sp, nkeys, kix, ret;
 
 	rcu_read_lock();
 
@@ -645,7 +651,9 @@ descend:
 
 ascend:
 	/* iterate through the remaining keys in this keyring */
-	for (; kix < keylist->nkeys; kix++) {
+	nkeys = keylist->nkeys;
+	smp_rmb();
+	for (; kix < nkeys; kix++) {
 		key = keylist->keys[kix];
 
 		if (key == A)
diff --git a/security/keys/trusted.c b/security/keys/trusted.c
index 0ed5fdf238a2..2d5d041f2049 100644
--- a/security/keys/trusted.c
+++ b/security/keys/trusted.c
@@ -993,7 +993,7 @@ out:
 	kfree(datablob);
 	kfree(options);
 	if (!ret)
-		rcu_assign_pointer(key->payload.data, payload);
+		rcu_assign_keypointer(key, payload);
 	else
 		kfree(payload);
 	return ret;
@@ -1067,7 +1067,7 @@ static int trusted_update(struct key *key, const void *data, size_t datalen)
 			goto out;
 		}
 	}
-	rcu_assign_pointer(key->payload.data, new_p);
+	rcu_assign_keypointer(key, new_p);
 	call_rcu(&p->rcu, trusted_rcu_free);
 out:
 	kfree(datablob);
diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c
index 69ff52c08e97..c7660a25a3e4 100644
--- a/security/keys/user_defined.c
+++ b/security/keys/user_defined.c
@@ -18,6 +18,8 @@
 #include <asm/uaccess.h>
 #include "internal.h"
 
+static int logon_vet_description(const char *desc);
+
 /*
  * user defined keys take an arbitrary string as the description and an
  * arbitrary blob of data as the payload
@@ -36,6 +38,24 @@ struct key_type key_type_user = {
 EXPORT_SYMBOL_GPL(key_type_user);
 
 /*
+ * This key type is essentially the same as key_type_user, but it does
+ * not define a .read op. This is suitable for storing username and
+ * password pairs in the keyring that you do not want to be readable
+ * from userspace.
+ */
+struct key_type key_type_logon = {
+	.name			= "logon",
+	.instantiate		= user_instantiate,
+	.update			= user_update,
+	.match			= user_match,
+	.revoke			= user_revoke,
+	.destroy		= user_destroy,
+	.describe		= user_describe,
+	.vet_description	= logon_vet_description,
+};
+EXPORT_SYMBOL_GPL(key_type_logon);
+
+/*
  * instantiate a user defined key
  */
 int user_instantiate(struct key *key, const void *data, size_t datalen)
@@ -59,7 +79,7 @@ int user_instantiate(struct key *key, const void *data, size_t datalen)
 	/* attach the data */
 	upayload->datalen = datalen;
 	memcpy(upayload->data, data, datalen);
-	rcu_assign_pointer(key->payload.data, upayload);
+	rcu_assign_keypointer(key, upayload);
 	ret = 0;
 
 error:
@@ -98,7 +118,7 @@ int user_update(struct key *key, const void *data, size_t datalen)
 	if (ret == 0) {
 		/* attach the new data, displacing the old */
 		zap = key->payload.data;
-		rcu_assign_pointer(key->payload.data, upayload);
+		rcu_assign_keypointer(key, upayload);
 		key->expiry = 0;
 	}
 
@@ -133,7 +153,7 @@ void user_revoke(struct key *key)
 	key_payload_reserve(key, 0);
 
 	if (upayload) {
-		rcu_assign_pointer(key->payload.data, NULL);
+		rcu_assign_keypointer(key, NULL);
 		kfree_rcu(upayload, rcu);
 	}
 }
@@ -189,3 +209,20 @@ long user_read(const struct key *key, char __user *buffer, size_t buflen)
 }
 
 EXPORT_SYMBOL_GPL(user_read);
+
+/* Vet the description for a "logon" key */
+static int logon_vet_description(const char *desc)
+{
+	char *p;
+
+	/* require a "qualified" description string */
+	p = strchr(desc, ':');
+	if (!p)
+		return -EINVAL;
+
+	/* also reject description with ':' as first char */
+	if (p == desc)
+		return -EINVAL;
+
+	return 0;
+}