From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FSL_HELO_FAKE,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C3E0C3F68F for ; Thu, 19 Dec 2019 00:12:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E594E22314 for ; Thu, 19 Dec 2019 00:12:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576714366; bh=t9eobqLU5zZnDpTX9F8DnN3q6+imrU5dEKYtoOZPHA4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=gjksa4sa0pP470aaaaruBNWwZsJ3ooVk5gDGyRrWSRc++jHEq/H8BAr7zsojKDgPN BOzsCqmIE/6K/MRYJMvEYQLE3hjz48aK05ABk46YpaeCRkAmrbXEZ8mpEYBp2WkOZt aMkkcg8dvBGQxlusMXILYptolXVohW6YiDumoaiY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726656AbfLSAMo (ORCPT ); Wed, 18 Dec 2019 19:12:44 -0500 Received: from mail.kernel.org ([198.145.29.99]:55838 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726559AbfLSAMo (ORCPT ); Wed, 18 Dec 2019 19:12:44 -0500 Received: from gmail.com (unknown [104.132.1.77]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 901942176D; Thu, 19 Dec 2019 00:12:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576714362; bh=t9eobqLU5zZnDpTX9F8DnN3q6+imrU5dEKYtoOZPHA4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=0TCswugXuHO49ooSCJVbRrpCPYkIxqkA3hkl9ik586Z+1nH9t9mtmBX04drzQ90F+ 10xVzVc/81szaOrGUrl89TpEoW6yzcPKqpr5ip53Vz38VE2l7z4LLKXLtm8YdJ7iHx O7fZxCX3iMQgSx5jxMyNuEsRtDa7tI/BttV1qs+Q= Date: Wed, 18 Dec 2019 16:12:41 -0800 From: Eric Biggers To: Satya Tangirala Cc: linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Barani Muthukumaran , Kuohong Wang , Kim Boojin , linux-ext4@vger.kernel.org Subject: Re: [PATCH v6 9/9] ext4: add inline encryption support Message-ID: <20191219001240.GD47399@gmail.com> References: <20191218145136.172774-1-satyat@google.com> <20191218145136.172774-10-satyat@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191218145136.172774-10-satyat@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org [+Cc linux-ext4] On Wed, Dec 18, 2019 at 06:51:36AM -0800, Satya Tangirala wrote: > Wire up ext4 to support inline encryption via the helper functions which > fs/crypto/ now provides. This includes: > > - Adding a mount option 'inlinecrypt' which enables inline encryption > on encrypted files where it can be used. > > - Setting the bio_crypt_ctx on bios that will be submitted to an > inline-encrypted file. > > Note: submit_bh_wbc() in fs/buffer.c also needed to be patched for > this part, since ext4 sometimes uses ll_rw_block() on file data. > > - Not adding logically discontiguous data to bios that will be submitted > to an inline-encrypted file. > > - Not doing filesystem-layer crypto on inline-encrypted files. > > Signed-off-by: Eric Biggers > Signed-off-by: Satya Tangirala In the next version can you please add linux-ext4 to Cc for the series? > --- > fs/buffer.c | 2 ++ > fs/ext4/ext4.h | 1 + > fs/ext4/inode.c | 4 ++-- > fs/ext4/page-io.c | 6 ++++-- > fs/ext4/readpage.c | 11 ++++++++--- > fs/ext4/super.c | 13 +++++++++++++ > 6 files changed, 30 insertions(+), 7 deletions(-) > > diff --git a/fs/buffer.c b/fs/buffer.c > index d8c7242426bb..3ad000db4a19 100644 > --- a/fs/buffer.c > +++ b/fs/buffer.c > @@ -3108,6 +3108,8 @@ static int submit_bh_wbc(int op, int op_flags, struct buffer_head *bh, > */ > bio = bio_alloc(GFP_NOIO, 1); > > + fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO); > + > bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9); > bio_set_dev(bio, bh->b_bdev); > bio->bi_write_hint = write_hint; In 5.5, there was some decryption code added to fs/buffer.c in order to support ext4 encryption with blocksize < PAGE_SIZE: static void end_buffer_async_read_io(struct buffer_head *bh, int uptodate) { /* Decrypt if needed */ if (uptodate && IS_ENABLED(CONFIG_FS_ENCRYPTION) && IS_ENCRYPTED(bh->b_page->mapping->host) && S_ISREG(bh->b_page->mapping->host->i_mode)) { ... This needs to be updated to use fscrypt_inode_uses_fs_layer_crypto() instead, so that the filesystem-layer decryption is not done when the file is already using inline decryption. > diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h > index f8578caba40d..aeaa01724d7c 100644 > --- a/fs/ext4/ext4.h > +++ b/fs/ext4/ext4.h > @@ -1153,6 +1153,7 @@ struct ext4_inode_info { > #define EXT4_MOUNT_JOURNAL_CHECKSUM 0x800000 /* Journal checksums */ > #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */ > #define EXT4_MOUNT_WARN_ON_ERROR 0x2000000 /* Trigger WARN_ON on error */ > +#define EXT4_MOUNT_INLINECRYPT 0x4000000 /* Inline encryption support */ > #define EXT4_MOUNT_DELALLOC 0x8000000 /* Delalloc support */ > #define EXT4_MOUNT_DATA_ERR_ABORT 0x10000000 /* Abort on file data write */ > #define EXT4_MOUNT_BLOCK_VALIDITY 0x20000000 /* Block validity checking */ > diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c > index 28f28de0c1b6..44d9651b8638 100644 > --- a/fs/ext4/inode.c > +++ b/fs/ext4/inode.c > @@ -1090,7 +1090,7 @@ static int ext4_block_write_begin(struct page *page, loff_t pos, unsigned len, > } > if (unlikely(err)) { > page_zero_new_buffers(page, from, to); > - } else if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode)) { > + } else if (fscrypt_inode_uses_fs_layer_crypto(inode)) { > for (i = 0; i < nr_wait; i++) { > int err2; > > @@ -3698,7 +3698,7 @@ static int __ext4_block_zero_page_range(handle_t *handle, > /* Uhhuh. Read error. Complain and punt. */ > if (!buffer_uptodate(bh)) > goto unlock; > - if (S_ISREG(inode->i_mode) && IS_ENCRYPTED(inode)) { > + if (fscrypt_inode_uses_fs_layer_crypto(inode)) { > /* We expect the key to be set. */ > BUG_ON(!fscrypt_has_encryption_key(inode)); > WARN_ON_ONCE(fscrypt_decrypt_pagecache_blocks( > diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c > index 24aeedb8fc75..acde754cc5ca 100644 > --- a/fs/ext4/page-io.c > +++ b/fs/ext4/page-io.c > @@ -404,6 +404,7 @@ static void io_submit_init_bio(struct ext4_io_submit *io, > * __GFP_DIRECT_RECLAIM is set, see comments for bio_alloc_bioset(). > */ > bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES); > + fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO); > bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9); > bio_set_dev(bio, bh->b_bdev); > bio->bi_end_io = ext4_end_bio; > @@ -420,7 +421,8 @@ static void io_submit_add_bh(struct ext4_io_submit *io, > { > int ret; > > - if (io->io_bio && bh->b_blocknr != io->io_next_block) { > + if (io->io_bio && (bh->b_blocknr != io->io_next_block || > + !fscrypt_mergeable_bio_bh(io->io_bio, bh))) { > submit_and_retry: > ext4_io_submit(io); > } > @@ -508,7 +510,7 @@ int ext4_bio_write_page(struct ext4_io_submit *io, > * (e.g. holes) to be unnecessarily encrypted, but this is rare and > * can't happen in the common case of blocksize == PAGE_SIZE. > */ > - if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode) && nr_to_submit) { > + if (fscrypt_inode_uses_fs_layer_crypto(inode) && nr_to_submit) { > gfp_t gfp_flags = GFP_NOFS; > unsigned int enc_bytes = round_up(len, i_blocksize(inode)); > > diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c > index fef7755300c3..7844e27518b4 100644 > --- a/fs/ext4/readpage.c > +++ b/fs/ext4/readpage.c > @@ -183,7 +183,7 @@ static struct bio_post_read_ctx *get_bio_post_read_ctx(struct inode *inode, > unsigned int post_read_steps = 0; > struct bio_post_read_ctx *ctx = NULL; > > - if (IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode)) > + if (fscrypt_inode_uses_fs_layer_crypto(inode)) > post_read_steps |= 1 << STEP_DECRYPT; > > if (ext4_need_verity(inode, first_idx)) > @@ -220,6 +220,7 @@ int ext4_mpage_readpages(struct address_space *mapping, > const unsigned blkbits = inode->i_blkbits; > const unsigned blocks_per_page = PAGE_SIZE >> blkbits; > const unsigned blocksize = 1 << blkbits; > + sector_t next_block; > sector_t block_in_file; > sector_t last_block; > sector_t last_block_in_file; > @@ -252,7 +253,8 @@ int ext4_mpage_readpages(struct address_space *mapping, > if (page_has_buffers(page)) > goto confused; > > - block_in_file = (sector_t)page->index << (PAGE_SHIFT - blkbits); > + block_in_file = next_block = > + (sector_t)page->index << (PAGE_SHIFT - blkbits); > last_block = block_in_file + nr_pages * blocks_per_page; > last_block_in_file = (ext4_readpage_limit(inode) + > blocksize - 1) >> blkbits; > @@ -352,7 +354,8 @@ int ext4_mpage_readpages(struct address_space *mapping, > * This page will go to BIO. Do we need to send this > * BIO off first? > */ > - if (bio && (last_block_in_bio != blocks[0] - 1)) { > + if (bio && (last_block_in_bio != blocks[0] - 1 || > + !fscrypt_mergeable_bio(bio, inode, next_block))) { > submit_and_realloc: > submit_bio(bio); > bio = NULL; > @@ -366,6 +369,8 @@ int ext4_mpage_readpages(struct address_space *mapping, > */ > bio = bio_alloc(GFP_KERNEL, > min_t(int, nr_pages, BIO_MAX_PAGES)); > + fscrypt_set_bio_crypt_ctx(bio, inode, next_block, > + GFP_KERNEL); > ctx = get_bio_post_read_ctx(inode, bio, page->index); > if (IS_ERR(ctx)) { > bio_put(bio); > diff --git a/fs/ext4/super.c b/fs/ext4/super.c > index 1d82b56d9b11..0a6b60620942 100644 > --- a/fs/ext4/super.c > +++ b/fs/ext4/super.c > @@ -1357,6 +1357,11 @@ static void ext4_get_ino_and_lblk_bits(struct super_block *sb, > *lblk_bits_ret = 8 * sizeof(ext4_lblk_t); > } > > +static bool ext4_inline_crypt_enabled(struct super_block *sb) > +{ > + return test_opt(sb, INLINECRYPT); > +} > + > static const struct fscrypt_operations ext4_cryptops = { > .key_prefix = "ext4:", > .get_context = ext4_get_context, > @@ -1366,6 +1371,7 @@ static const struct fscrypt_operations ext4_cryptops = { > .max_namelen = EXT4_NAME_LEN, > .has_stable_inodes = ext4_has_stable_inodes, > .get_ino_and_lblk_bits = ext4_get_ino_and_lblk_bits, > + .inline_crypt_enabled = ext4_inline_crypt_enabled, > }; > #endif > > @@ -1460,6 +1466,7 @@ enum { > Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit, > Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback, > Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption, > + Opt_inlinecrypt, > Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota, > Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota, > Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err, > @@ -1556,6 +1563,7 @@ static const match_table_t tokens = { > {Opt_noinit_itable, "noinit_itable"}, > {Opt_max_dir_size_kb, "max_dir_size_kb=%u"}, > {Opt_test_dummy_encryption, "test_dummy_encryption"}, > + {Opt_inlinecrypt, "inlinecrypt"}, > {Opt_nombcache, "nombcache"}, > {Opt_nombcache, "no_mbcache"}, /* for backward compatibility */ > {Opt_removed, "check=none"}, /* mount option from ext2/3 */ > @@ -1767,6 +1775,11 @@ static const struct mount_opts { > {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT}, > {Opt_max_dir_size_kb, 0, MOPT_GTE0}, > {Opt_test_dummy_encryption, 0, MOPT_GTE0}, > +#ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT > + {Opt_inlinecrypt, EXT4_MOUNT_INLINECRYPT, MOPT_SET}, > +#else > + {Opt_inlinecrypt, EXT4_MOUNT_INLINECRYPT, MOPT_NOSUPPORT}, > +#endif > {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET}, > {Opt_err, 0, 0} > }; On v5 there was a discussion about using a flag like SB_INLINECRYPT to replace the ->inline_crypt_enabled() function. Was this considered? - Eric