diff options
Diffstat (limited to 'fs/crypto/keyring.c')
| -rw-r--r-- | fs/crypto/keyring.c | 35 |
1 files changed, 19 insertions, 16 deletions
diff --git a/fs/crypto/keyring.c b/fs/crypto/keyring.c index 78086f8dbda5..7cbb1fd872ac 100644 --- a/fs/crypto/keyring.c +++ b/fs/crypto/keyring.c @@ -73,7 +73,7 @@ void fscrypt_put_master_key(struct fscrypt_master_key *mk) * fscrypt_master_key struct itself after an RCU grace period ensures * that concurrent keyring lookups can no longer find it. */ - WARN_ON(refcount_read(&mk->mk_active_refs) != 0); + WARN_ON_ONCE(refcount_read(&mk->mk_active_refs) != 0); key_put(mk->mk_users); mk->mk_users = NULL; call_rcu(&mk->mk_rcu_head, fscrypt_free_master_key); @@ -92,6 +92,8 @@ void fscrypt_put_master_key_activeref(struct super_block *sb, * destroying any subkeys embedded in it. */ + if (WARN_ON_ONCE(!sb->s_master_keys)) + return; spin_lock(&sb->s_master_keys->lock); hlist_del_rcu(&mk->mk_node); spin_unlock(&sb->s_master_keys->lock); @@ -100,8 +102,8 @@ void fscrypt_put_master_key_activeref(struct super_block *sb, * ->mk_active_refs == 0 implies that ->mk_secret is not present and * that ->mk_decrypted_inodes is empty. */ - WARN_ON(is_master_key_secret_present(&mk->mk_secret)); - WARN_ON(!list_empty(&mk->mk_decrypted_inodes)); + WARN_ON_ONCE(is_master_key_secret_present(&mk->mk_secret)); + WARN_ON_ONCE(!list_empty(&mk->mk_decrypted_inodes)); for (i = 0; i <= FSCRYPT_MODE_MAX; i++) { fscrypt_destroy_prepared_key( @@ -207,10 +209,11 @@ static int allocate_filesystem_keyring(struct super_block *sb) * Release all encryption keys that have been added to the filesystem, along * with the keyring that contains them. * - * This is called at unmount time. The filesystem's underlying block device(s) - * are still available at this time; this is important because after user file - * accesses have been allowed, this function may need to evict keys from the - * keyslots of an inline crypto engine, which requires the block device(s). + * This is called at unmount time, after all potentially-encrypted inodes have + * been evicted. The filesystem's underlying block device(s) are still + * available at this time; this is important because after user file accesses + * have been allowed, this function may need to evict keys from the keyslots of + * an inline crypto engine, which requires the block device(s). */ void fscrypt_destroy_keyring(struct super_block *sb) { @@ -227,16 +230,16 @@ void fscrypt_destroy_keyring(struct super_block *sb) hlist_for_each_entry_safe(mk, tmp, bucket, mk_node) { /* - * Since all inodes were already evicted, every key - * remaining in the keyring should have an empty inode - * list, and should only still be in the keyring due to - * the single active ref associated with ->mk_secret. - * There should be no structural refs beyond the one - * associated with the active ref. + * Since all potentially-encrypted inodes were already + * evicted, every key remaining in the keyring should + * have an empty inode list, and should only still be in + * the keyring due to the single active ref associated + * with ->mk_secret. There should be no structural refs + * beyond the one associated with the active ref. */ - WARN_ON(refcount_read(&mk->mk_active_refs) != 1); - WARN_ON(refcount_read(&mk->mk_struct_refs) != 1); - WARN_ON(!is_master_key_secret_present(&mk->mk_secret)); + WARN_ON_ONCE(refcount_read(&mk->mk_active_refs) != 1); + WARN_ON_ONCE(refcount_read(&mk->mk_struct_refs) != 1); + WARN_ON_ONCE(!is_master_key_secret_present(&mk->mk_secret)); wipe_master_key_secret(&mk->mk_secret); fscrypt_put_master_key_activeref(sb, mk); } |