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Diffstat (limited to 'security/keys/key.c')
-rw-r--r--security/keys/key.c199
1 files changed, 136 insertions, 63 deletions
diff --git a/security/keys/key.c b/security/keys/key.c
index c45afdd1dfbb..3bbdde778631 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -13,7 +13,6 @@
#include <linux/security.h>
#include <linux/workqueue.h>
#include <linux/random.h>
-#include <linux/ima.h>
#include <linux/err.h>
#include "internal.h"
@@ -231,6 +230,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
struct key *key;
size_t desclen, quotalen;
int ret;
+ unsigned long irqflags;
key = ERR_PTR(-EINVAL);
if (!desc || !*desc)
@@ -260,7 +260,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
unsigned maxbytes = uid_eq(uid, GLOBAL_ROOT_UID) ?
key_quota_root_maxbytes : key_quota_maxbytes;
- spin_lock(&user->lock);
+ spin_lock_irqsave(&user->lock, irqflags);
if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) {
if (user->qnkeys + 1 > maxkeys ||
user->qnbytes + quotalen > maxbytes ||
@@ -270,7 +270,7 @@ struct key *key_alloc(struct key_type *type, const char *desc,
user->qnkeys++;
user->qnbytes += quotalen;
- spin_unlock(&user->lock);
+ spin_unlock_irqrestore(&user->lock, irqflags);
}
/* allocate and initialise the key and its description */
@@ -294,9 +294,11 @@ struct key *key_alloc(struct key_type *type, const char *desc,
key->uid = uid;
key->gid = gid;
key->perm = perm;
+ key->expiry = TIME64_MAX;
key->restrict_link = restrict_link;
key->last_used_at = ktime_get_real_seconds();
+ key->flags |= 1 << KEY_FLAG_USER_ALIVE;
if (!(flags & KEY_ALLOC_NOT_IN_QUOTA))
key->flags |= 1 << KEY_FLAG_IN_QUOTA;
if (flags & KEY_ALLOC_BUILT_IN)
@@ -327,10 +329,10 @@ security_error:
kfree(key->description);
kmem_cache_free(key_jar, key);
if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) {
- spin_lock(&user->lock);
+ spin_lock_irqsave(&user->lock, irqflags);
user->qnkeys--;
user->qnbytes -= quotalen;
- spin_unlock(&user->lock);
+ spin_unlock_irqrestore(&user->lock, irqflags);
}
key_user_put(user);
key = ERR_PTR(ret);
@@ -340,10 +342,10 @@ no_memory_3:
kmem_cache_free(key_jar, key);
no_memory_2:
if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) {
- spin_lock(&user->lock);
+ spin_lock_irqsave(&user->lock, irqflags);
user->qnkeys--;
user->qnbytes -= quotalen;
- spin_unlock(&user->lock);
+ spin_unlock_irqrestore(&user->lock, irqflags);
}
key_user_put(user);
no_memory_1:
@@ -351,7 +353,7 @@ no_memory_1:
goto error;
no_quota:
- spin_unlock(&user->lock);
+ spin_unlock_irqrestore(&user->lock, irqflags);
key_user_put(user);
key = ERR_PTR(-EDQUOT);
goto error;
@@ -380,8 +382,9 @@ int key_payload_reserve(struct key *key, size_t datalen)
if (delta != 0 && test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
unsigned maxbytes = uid_eq(key->user->uid, GLOBAL_ROOT_UID) ?
key_quota_root_maxbytes : key_quota_maxbytes;
+ unsigned long flags;
- spin_lock(&key->user->lock);
+ spin_lock_irqsave(&key->user->lock, flags);
if (delta > 0 &&
(key->user->qnbytes + delta > maxbytes ||
@@ -392,7 +395,7 @@ int key_payload_reserve(struct key *key, size_t datalen)
key->user->qnbytes += delta;
key->quotalen += delta;
}
- spin_unlock(&key->user->lock);
+ spin_unlock_irqrestore(&key->user->lock, flags);
}
/* change the recorded data length if that didn't generate an error */
@@ -463,10 +466,8 @@ static int __key_instantiate_and_link(struct key *key,
if (authkey)
key_invalidate(authkey);
- if (prep->expiry != TIME64_MAX) {
- key->expiry = prep->expiry;
- key_schedule_gc(prep->expiry + key_gc_delay);
- }
+ if (prep->expiry != TIME64_MAX)
+ key_set_expiry(key, prep->expiry);
}
}
@@ -606,8 +607,7 @@ int key_reject_and_link(struct key *key,
atomic_inc(&key->user->nikeys);
mark_key_instantiated(key, -error);
notify_key(key, NOTIFY_KEY_INSTANTIATED, -error);
- key->expiry = ktime_get_real_seconds() + timeout;
- key_schedule_gc(key->expiry + key_gc_delay);
+ key_set_expiry(key, ktime_get_real_seconds() + timeout);
if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags))
awaken = 1;
@@ -649,8 +649,20 @@ void key_put(struct key *key)
if (key) {
key_check(key);
- if (refcount_dec_and_test(&key->usage))
+ if (refcount_dec_and_test(&key->usage)) {
+ unsigned long flags;
+
+ /* deal with the user's key tracking and quota */
+ if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+ spin_lock_irqsave(&key->user->lock, flags);
+ key->user->qnkeys--;
+ key->user->qnbytes -= key->quotalen;
+ spin_unlock_irqrestore(&key->user->lock, flags);
+ }
+ /* Mark key as safe for GC after key->user done. */
+ clear_bit_unlock(KEY_FLAG_USER_ALIVE, &key->flags);
schedule_work(&key_gc_work);
+ }
}
}
EXPORT_SYMBOL(key_put);
@@ -693,6 +705,7 @@ error:
spin_unlock(&key_serial_lock);
return key;
}
+EXPORT_SYMBOL(key_lookup);
/*
* Find and lock the specified key type against removal.
@@ -722,16 +735,14 @@ found_kernel_type:
void key_set_timeout(struct key *key, unsigned timeout)
{
- time64_t expiry = 0;
+ time64_t expiry = TIME64_MAX;
/* make the changes with the locks held to prevent races */
down_write(&key->sem);
if (timeout > 0)
expiry = ktime_get_real_seconds() + timeout;
-
- key->expiry = expiry;
- key_schedule_gc(key->expiry + key_gc_delay);
+ key_set_expiry(key, expiry);
up_write(&key->sem);
}
@@ -788,38 +799,18 @@ error:
goto out;
}
-/**
- * key_create_or_update - Update or create and instantiate a key.
- * @keyring_ref: A pointer to the destination keyring with possession flag.
- * @type: The type of key.
- * @description: The searchable description for the key.
- * @payload: The data to use to instantiate or update the key.
- * @plen: The length of @payload.
- * @perm: The permissions mask for a new key.
- * @flags: The quota flags for a new key.
- *
- * Search the destination keyring for a key of the same description and if one
- * is found, update it, otherwise create and instantiate a new one and create a
- * link to it from that keyring.
- *
- * If perm is KEY_PERM_UNDEF then an appropriate key permissions mask will be
- * concocted.
- *
- * Returns a pointer to the new key if successful, -ENODEV if the key type
- * wasn't available, -ENOTDIR if the keyring wasn't a keyring, -EACCES if the
- * caller isn't permitted to modify the keyring or the LSM did not permit
- * creation of the key.
- *
- * On success, the possession flag from the keyring ref will be tacked on to
- * the key ref before it is returned.
+/*
+ * Create or potentially update a key. The combined logic behind
+ * key_create_or_update() and key_create()
*/
-key_ref_t key_create_or_update(key_ref_t keyring_ref,
- const char *type,
- const char *description,
- const void *payload,
- size_t plen,
- key_perm_t perm,
- unsigned long flags)
+static key_ref_t __key_create_or_update(key_ref_t keyring_ref,
+ const char *type,
+ const char *description,
+ const void *payload,
+ size_t plen,
+ key_perm_t perm,
+ unsigned long flags,
+ bool allow_update)
{
struct keyring_index_key index_key = {
.description = description,
@@ -906,14 +897,23 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
goto error_link_end;
}
- /* if it's possible to update this type of key, search for an existing
- * key of the same type and description in the destination keyring and
- * update that instead if possible
+ /* if it's requested and possible to update this type of key, search
+ * for an existing key of the same type and description in the
+ * destination keyring and update that instead if possible
*/
- if (index_key.type->update) {
+ if (allow_update) {
+ if (index_key.type->update) {
+ key_ref = find_key_to_update(keyring_ref, &index_key);
+ if (key_ref)
+ goto found_matching_key;
+ }
+ } else {
key_ref = find_key_to_update(keyring_ref, &index_key);
- if (key_ref)
- goto found_matching_key;
+ if (key_ref) {
+ key_ref_put(key_ref);
+ key_ref = ERR_PTR(-EEXIST);
+ goto error_link_end;
+ }
}
/* if the client doesn't provide, decide on the permissions we want */
@@ -945,8 +945,8 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
goto error_link_end;
}
- ima_post_key_create_or_update(keyring, key, payload, plen,
- flags, true);
+ security_key_post_create_or_update(keyring, key, payload, plen, flags,
+ true);
key_ref = make_key_ref(key, is_key_possessed(keyring_ref));
@@ -979,15 +979,88 @@ error:
key_ref = __key_update(key_ref, &prep);
if (!IS_ERR(key_ref))
- ima_post_key_create_or_update(keyring, key,
- payload, plen,
- flags, false);
+ security_key_post_create_or_update(keyring, key, payload, plen,
+ flags, false);
goto error_free_prep;
}
+
+/**
+ * key_create_or_update - Update or create and instantiate a key.
+ * @keyring_ref: A pointer to the destination keyring with possession flag.
+ * @type: The type of key.
+ * @description: The searchable description for the key.
+ * @payload: The data to use to instantiate or update the key.
+ * @plen: The length of @payload.
+ * @perm: The permissions mask for a new key.
+ * @flags: The quota flags for a new key.
+ *
+ * Search the destination keyring for a key of the same description and if one
+ * is found, update it, otherwise create and instantiate a new one and create a
+ * link to it from that keyring.
+ *
+ * If perm is KEY_PERM_UNDEF then an appropriate key permissions mask will be
+ * concocted.
+ *
+ * Returns a pointer to the new key if successful, -ENODEV if the key type
+ * wasn't available, -ENOTDIR if the keyring wasn't a keyring, -EACCES if the
+ * caller isn't permitted to modify the keyring or the LSM did not permit
+ * creation of the key.
+ *
+ * On success, the possession flag from the keyring ref will be tacked on to
+ * the key ref before it is returned.
+ */
+key_ref_t key_create_or_update(key_ref_t keyring_ref,
+ const char *type,
+ const char *description,
+ const void *payload,
+ size_t plen,
+ key_perm_t perm,
+ unsigned long flags)
+{
+ return __key_create_or_update(keyring_ref, type, description, payload,
+ plen, perm, flags, true);
+}
EXPORT_SYMBOL(key_create_or_update);
/**
+ * key_create - Create and instantiate a key.
+ * @keyring_ref: A pointer to the destination keyring with possession flag.
+ * @type: The type of key.
+ * @description: The searchable description for the key.
+ * @payload: The data to use to instantiate or update the key.
+ * @plen: The length of @payload.
+ * @perm: The permissions mask for a new key.
+ * @flags: The quota flags for a new key.
+ *
+ * Create and instantiate a new key and link to it from the destination keyring.
+ *
+ * If perm is KEY_PERM_UNDEF then an appropriate key permissions mask will be
+ * concocted.
+ *
+ * Returns a pointer to the new key if successful, -EEXIST if a key with the
+ * same description already exists, -ENODEV if the key type wasn't available,
+ * -ENOTDIR if the keyring wasn't a keyring, -EACCES if the caller isn't
+ * permitted to modify the keyring or the LSM did not permit creation of the
+ * key.
+ *
+ * On success, the possession flag from the keyring ref will be tacked on to
+ * the key ref before it is returned.
+ */
+key_ref_t key_create(key_ref_t keyring_ref,
+ const char *type,
+ const char *description,
+ const void *payload,
+ size_t plen,
+ key_perm_t perm,
+ unsigned long flags)
+{
+ return __key_create_or_update(keyring_ref, type, description, payload,
+ plen, perm, flags, false);
+}
+EXPORT_SYMBOL(key_create);
+
+/**
* key_update - Update a key's contents.
* @key_ref: The pointer (plus possession flag) to the key.
* @payload: The data to be used to update the key.