KEYS: Do preallocation for __key_link()

[pandora-kernel.git] / security / keys / request_key.c

diff --git a/security/keys/request_key.c b/security/keys/request_key.c
index ac49c8a..f656e9c 100644 (file)
--- a/security/keys/request_key.c
+++ b/security/keys/request_key.c
@@ -299,6 +299,7 @@ static int construct_alloc_key(struct key_type *type,
                               struct key_user *user,
                               struct key **_key)
 {
+       struct keyring_list *prealloc;
        const struct cred *cred = current_cred();
        struct key *key;
        key_ref_t key_ref;
@@ -306,6 +307,7 @@ static int construct_alloc_key(struct key_type *type,
 
        kenter("%s,%s,,,", type->name, description);
 
+       *_key = NULL;
        mutex_lock(&user->cons_lock);
 
        key = key_alloc(type, description, cred->fsuid, cred->fsgid, cred,
@@ -315,8 +317,12 @@ static int construct_alloc_key(struct key_type *type,
 
        set_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags);
 
-       if (dest_keyring)
-               down_write(&dest_keyring->sem);
+       if (dest_keyring) {
+               ret = __key_link_begin(dest_keyring, type, description,
+                                      &prealloc);
+               if (ret < 0)
+                       goto link_prealloc_failed;
+       }
 
        /* attach the key to the destination keyring under lock, but we do need
         * to do another check just in case someone beat us to it whilst we
@@ -328,11 +334,11 @@ static int construct_alloc_key(struct key_type *type,
                goto key_already_present;
 
        if (dest_keyring)
-               __key_link(dest_keyring, key);
+               __key_link(dest_keyring, key, &prealloc);
 
        mutex_unlock(&key_construction_mutex);
        if (dest_keyring)
-               up_write(&dest_keyring->sem);
+               __key_link_end(dest_keyring, type, prealloc);
        mutex_unlock(&user->cons_lock);
        *_key = key;
        kleave(" = 0 [%d]", key_serial(key));
@@ -341,27 +347,36 @@ static int construct_alloc_key(struct key_type *type,
        /* the key is now present - we tell the caller that we found it by
         * returning -EINPROGRESS  */
 key_already_present:
+       key_put(key);
        mutex_unlock(&key_construction_mutex);
-       ret = 0;
+       key = key_ref_to_ptr(key_ref);
        if (dest_keyring) {
-               ret = __key_link(dest_keyring, key_ref_to_ptr(key_ref));
-               up_write(&dest_keyring->sem);
+               ret = __key_link_check_live_key(dest_keyring, key);
+               if (ret == 0)
+                       __key_link(dest_keyring, key, &prealloc);
+               __key_link_end(dest_keyring, type, prealloc);
+               if (ret < 0)
+                       goto link_check_failed;
        }
        mutex_unlock(&user->cons_lock);
-       key_put(key);
-       if (ret < 0) {
-               key_ref_put(key_ref);
-               *_key = NULL;
-               kleave(" = %d [link]", ret);
-               return ret;
-       }
-       *_key = key = key_ref_to_ptr(key_ref);
+       *_key = key;
        kleave(" = -EINPROGRESS [%d]", key_serial(key));
        return -EINPROGRESS;
 
+link_check_failed:
+       mutex_unlock(&user->cons_lock);
+       key_put(key);
+       kleave(" = %d [linkcheck]", ret);
+       return ret;
+
+link_prealloc_failed:
+       up_write(&dest_keyring->sem);
+       mutex_unlock(&user->cons_lock);
+       kleave(" = %d [prelink]", ret);
+       return ret;
+
 alloc_failed:
        mutex_unlock(&user->cons_lock);
-       *_key = NULL;
        kleave(" = %ld", PTR_ERR(key));
        return PTR_ERR(key);
 }