From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:38056 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2393379AbfJPWOq (ORCPT ); Wed, 16 Oct 2019 18:14:46 -0400 From: Eric Biggers Subject: [PATCH 2/2] ext4: Enable encryption for subpage-sized blocks Date: Wed, 16 Oct 2019 15:11:42 -0700 Message-Id: <20191016221142.298754-3-ebiggers@kernel.org> In-Reply-To: <20191016221142.298754-1-ebiggers@kernel.org> References: <20191016221142.298754-1-ebiggers@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-fscrypt-owner@vger.kernel.org To: linux-ext4@vger.kernel.org Cc: linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org, Chandan Rajendra List-ID: From: Chandan Rajendra Now that we have the code to support encryption for subpage-sized blocks, this commit removes the conditional check in filesystem mount code. The commit also changes the support statement in Documentation/filesystems/fscrypt.rst to reflect the fact that encryption on filesystems with blocksize less than page size now works. [EB: Tested with 'gce-xfstests -c ext4/encrypt_1k -g auto', using the new "encrypt_1k" config I created. All tests pass except for those that already fail or are excluded with the encrypt or 1k configs, and 2 tests that try to create 1023-byte symlinks which fails since encrypted symlinks are limited to blocksize-3 bytes. Also ran the dedicated encryption tests using 'kvm-xfstests -c ext4/1k -g encrypt'; all pass, including the on-disk ciphertext verification tests.] Signed-off-by: Chandan Rajendra Signed-off-by: Eric Biggers --- Documentation/filesystems/fscrypt.rst | 4 ++-- fs/ext4/super.c | 7 ------- 2 files changed, 2 insertions(+), 9 deletions(-) diff --git a/Documentation/filesystems/fscrypt.rst b/Documentation/filesystems/fscrypt.rst index 8a0700af9596..b0d015a8cdc3 100644 --- a/Documentation/filesystems/fscrypt.rst +++ b/Documentation/filesystems/fscrypt.rst @@ -331,8 +331,8 @@ Contents encryption ------------------- For file contents, each filesystem block is encrypted independently. -Currently, only the case where the filesystem block size is equal to -the system's page size (usually 4096 bytes) is supported. +Starting from Linux kernel 5.5, encryption of filesystems with block +size less than system's page size is supported. Each block's IV is set to the logical block number within the file as a little endian number, except that: diff --git a/fs/ext4/super.c b/fs/ext4/super.c index dd654e53ba3d..369f852bef20 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4439,13 +4439,6 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) } } - if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) && - (blocksize != PAGE_SIZE)) { - ext4_msg(sb, KERN_ERR, - "Unsupported blocksize for fs encryption"); - goto failed_mount_wq; - } - if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) { ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity"); goto failed_mount_wq; -- 2.23.0