diff options
Diffstat (limited to 'fs/crypto/keyring.c')
| -rw-r--r-- | fs/crypto/keyring.c | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/fs/crypto/keyring.c b/fs/crypto/keyring.c index e24eb48bfbe1..71d56f8e2870 100644 --- a/fs/crypto/keyring.c +++ b/fs/crypto/keyring.c @@ -45,9 +45,9 @@ static void free_master_key(struct fscrypt_master_key *mk) wipe_master_key_secret(&mk->mk_secret); for (i = 0; i <= __FSCRYPT_MODE_MAX; i++) { - crypto_free_skcipher(mk->mk_direct_keys[i]); - crypto_free_skcipher(mk->mk_iv_ino_lblk_64_keys[i]); - crypto_free_skcipher(mk->mk_iv_ino_lblk_32_keys[i]); + fscrypt_destroy_prepared_key(&mk->mk_direct_keys[i]); + fscrypt_destroy_prepared_key(&mk->mk_iv_ino_lblk_64_keys[i]); + fscrypt_destroy_prepared_key(&mk->mk_iv_ino_lblk_32_keys[i]); } key_put(mk->mk_users); @@ -213,7 +213,11 @@ static int allocate_filesystem_keyring(struct super_block *sb) if (IS_ERR(keyring)) return PTR_ERR(keyring); - /* Pairs with READ_ONCE() in fscrypt_find_master_key() */ + /* + * Pairs with the smp_load_acquire() in fscrypt_find_master_key(). + * I.e., here we publish ->s_master_keys with a RELEASE barrier so that + * concurrent tasks can ACQUIRE it. + */ smp_store_release(&sb->s_master_keys, keyring); return 0; } @@ -234,8 +238,13 @@ struct key *fscrypt_find_master_key(struct super_block *sb, struct key *keyring; char description[FSCRYPT_MK_DESCRIPTION_SIZE]; - /* pairs with smp_store_release() in allocate_filesystem_keyring() */ - keyring = READ_ONCE(sb->s_master_keys); + /* + * Pairs with the smp_store_release() in allocate_filesystem_keyring(). + * I.e., another task can publish ->s_master_keys concurrently, + * executing a RELEASE barrier. We need to use smp_load_acquire() here + * to safely ACQUIRE the memory the other task published. + */ + keyring = smp_load_acquire(&sb->s_master_keys); if (keyring == NULL) return ERR_PTR(-ENOKEY); /* No keyring yet, so no keys yet. */ |