diff options
Diffstat (limited to 'fs/crypto/fscrypt_private.h')
| -rw-r--r-- | fs/crypto/fscrypt_private.h | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h index bc1a3fcd45ed..8117a61b6f55 100644 --- a/fs/crypto/fscrypt_private.h +++ b/fs/crypto/fscrypt_private.h @@ -351,13 +351,16 @@ fscrypt_is_key_prepared(struct fscrypt_prepared_key *prep_key, const struct fscrypt_info *ci) { /* - * The READ_ONCE() here pairs with the smp_store_release() in - * fscrypt_prepare_key(). (This only matters for the per-mode keys, - * which are shared by multiple inodes.) + * The two smp_load_acquire()'s here pair with the smp_store_release()'s + * in fscrypt_prepare_inline_crypt_key() and fscrypt_prepare_key(). + * I.e., in some cases (namely, if this prep_key is a per-mode + * encryption key) another task can publish blk_key or tfm concurrently, + * executing a RELEASE barrier. We need to use smp_load_acquire() here + * to safely ACQUIRE the memory the other task published. */ if (fscrypt_using_inline_encryption(ci)) - return READ_ONCE(prep_key->blk_key) != NULL; - return READ_ONCE(prep_key->tfm) != NULL; + return smp_load_acquire(&prep_key->blk_key) != NULL; + return smp_load_acquire(&prep_key->tfm) != NULL; } #else /* CONFIG_FS_ENCRYPTION_INLINE_CRYPT */ @@ -391,7 +394,7 @@ static inline bool fscrypt_is_key_prepared(struct fscrypt_prepared_key *prep_key, const struct fscrypt_info *ci) { - return READ_ONCE(prep_key->tfm) != NULL; + return smp_load_acquire(&prep_key->tfm) != NULL; } #endif /* !CONFIG_FS_ENCRYPTION_INLINE_CRYPT */ |