From b8f7b236748261bec545b69b39d7fb75e519f4ed Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Thu, 24 Oct 2019 14:44:31 -0700 Subject: [PATCH] BACKPORT: FROMLIST: ext4: add inline encryption support 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. Bug: 137270441 Test: tested as series; see Ie1b77f7615d6a7a60fdc9105c7ab2200d17636a8 Change-Id: I73dac46ff1eba56a13975c387b20554416ddbad8 Signed-off-by: Eric Biggers Signed-off-by: Satya Tangirala Link: https://lore.kernel.org/linux-fscrypt/20191028072032.6911-10-satyat@google.com/ --- fs/buffer.c | 3 +++ fs/ext4/ext4.h | 1 + fs/ext4/inode.c | 4 ++-- fs/ext4/page-io.c | 11 +++++++++-- fs/ext4/readpage.c | 15 ++++++++++++--- fs/ext4/super.c | 13 +++++++++++++ 6 files changed, 40 insertions(+), 7 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index bdca7b10e239..30315edcfd91 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -46,6 +46,7 @@ #include #include #include +#include static int fsync_buffers_list(spinlock_t *lock, struct list_head *list); static int submit_bh_wbc(int op, int op_flags, struct buffer_head *bh, @@ -3125,6 +3126,8 @@ 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 | __GFP_NOFAIL); + if (wbc) { wbc_init_bio(wbc, bio); wbc_account_io(wbc, bh->b_page, bh->b_size); diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index b993e4df016a..9decc3e73ca4 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1155,6 +1155,7 @@ struct ext4_inode_info { #define EXT4_MOUNT_DIOREAD_NOLOCK 0x400000 /* Enable support for dio read nolocking */ #define EXT4_MOUNT_JOURNAL_CHECKSUM 0x800000 /* Journal checksums */ #define EXT4_MOUNT_JOURNAL_ASYNC_COMMIT 0x1000000 /* Journal Async Commit */ +#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 e2b466fd7f3a..0aefed560d91 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1232,7 +1232,7 @@ static int ext4_block_write_begin(struct page *page, loff_t pos, unsigned len, (block_start < from || block_end > to)) { ll_rw_block(REQ_OP_READ, 0, 1, &bh); *wait_bh++ = bh; - decrypt = IS_ENCRYPTED(inode) && S_ISREG(inode->i_mode); + decrypt = fscrypt_inode_uses_fs_layer_crypto(inode); } } /* @@ -4061,7 +4061,7 @@ 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)); BUG_ON(blocksize != PAGE_SIZE); diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c index b028265a1fbb..9d547bace7f2 100644 --- a/fs/ext4/page-io.c +++ b/fs/ext4/page-io.c @@ -362,10 +362,16 @@ static int io_submit_init_bio(struct ext4_io_submit *io, struct buffer_head *bh) { struct bio *bio; + int err; bio = bio_alloc(GFP_NOIO, BIO_MAX_PAGES); if (!bio) return -ENOMEM; + err = fscrypt_set_bio_crypt_ctx_bh(bio, bh, GFP_NOIO); + if (err) { + bio_put(bio); + return err; + } wbc_init_bio(io->io_wbc, bio); bio->bi_iter.bi_sector = bh->b_blocknr * (bh->b_size >> 9); bio_set_dev(bio, bh->b_bdev); @@ -383,7 +389,8 @@ static int 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); } @@ -469,7 +476,7 @@ int ext4_bio_write_page(struct ext4_io_submit *io, bh = head = page_buffers(page); - 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; retry_encrypt: diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c index f74dead3fcc0..a92409f1d0ae 100644 --- a/fs/ext4/readpage.c +++ b/fs/ext4/readpage.c @@ -198,7 +198,7 @@ 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)) @@ -259,6 +259,7 @@ 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; @@ -290,7 +291,8 @@ 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; @@ -390,7 +392,8 @@ 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: ext4_submit_bio_read(bio); bio = NULL; @@ -402,6 +405,12 @@ int ext4_mpage_readpages(struct address_space *mapping, min_t(int, nr_pages, BIO_MAX_PAGES)); if (!bio) goto set_error_page; + if (fscrypt_set_bio_crypt_ctx(bio, inode, next_block, + GFP_KERNEL) != 0) { + bio_put(bio); + bio = NULL; + goto set_error_page; + } 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 96235d0cc01c..25fe536638d0 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1297,6 +1297,11 @@ 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, @@ -1306,6 +1311,7 @@ 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 @@ -1400,6 +1406,7 @@ 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, @@ -1493,6 +1500,7 @@ 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 */ @@ -1702,6 +1710,11 @@ 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} };