From patchwork Sat Jan 7 08:28:26 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 134817 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id C71C9B6F7E for ; Sat, 7 Jan 2012 19:36:28 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751660Ab2AGIgX (ORCPT ); Sat, 7 Jan 2012 03:36:23 -0500 Received: from e38.co.us.ibm.com ([32.97.110.159]:48551 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752525Ab2AGI2c (ORCPT ); Sat, 7 Jan 2012 03:28:32 -0500 Received: from /spool/local by e38.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Sat, 7 Jan 2012 01:28:31 -0700 Received: from d03relay02.boulder.ibm.com (9.17.195.227) by e38.co.us.ibm.com (192.168.1.138) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Sat, 7 Jan 2012 01:28:29 -0700 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay02.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q078ST1v130660; Sat, 7 Jan 2012 01:28:29 -0700 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q078SR9w024182; Sat, 7 Jan 2012 01:28:29 -0700 Received: from elm3c44.beaverton.ibm.com (elm3c44.beaverton.ibm.com [9.47.69.44]) by d03av02.boulder.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id q078SQNW024164; Sat, 7 Jan 2012 01:28:26 -0700 Subject: [PATCH 05/23] ext4: Calculate and verify superblock checksum To: Andreas Dilger , Theodore Tso , "Darrick J. Wong" From: "Darrick J. Wong" Cc: Sunil Mushran , Martin K Petersen , Greg Freemyer , Amir Goldstein , linux-kernel , Andi Kleen , Mingming Cao , Joel Becker , linux-fsdevel , linux-ext4@vger.kernel.org, Coly Li Date: Sat, 07 Jan 2012 00:28:26 -0800 Message-ID: <20120107082826.21970.33859.stgit@elm3c44.beaverton.ibm.com> In-Reply-To: <20120107082751.21970.84856.stgit@elm3c44.beaverton.ibm.com> References: <20120107082751.21970.84856.stgit@elm3c44.beaverton.ibm.com> User-Agent: StGit/0.15 MIME-Version: 1.0 x-cbid: 12010708-5518-0000-0000-0000016564C7 Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org Calculate and verify the superblock checksum. Since the UUID and block group number are embedded in each copy of the superblock, we need only checksum the entire block. Refactor some of the code to eliminate open-coding of the checksum update call. Signed-off-by: Darrick J. Wong --- fs/ext4/ext4.h | 10 ++++++++++ fs/ext4/ext4_jbd2.c | 9 ++++++++- fs/ext4/ext4_jbd2.h | 7 +++++-- fs/ext4/inode.c | 3 +-- fs/ext4/namei.c | 4 ++-- fs/ext4/resize.c | 6 +++++- fs/ext4/super.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 7 files changed, 78 insertions(+), 8 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index a6de0d2..9d1504e 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1263,6 +1263,9 @@ struct ext4_sb_info { /* Reference to checksum algorithm driver via cryptoapi */ struct crypto_shash *s_chksum_driver; + + /* Precomputed FS UUID checksum for seeding other checksums */ + __u32 s_csum_seed; }; static inline struct ext4_sb_info *EXT4_SB(struct super_block *sb) @@ -1976,6 +1979,10 @@ extern int ext4_group_extend(struct super_block *sb, ext4_fsblk_t n_blocks_count); /* super.c */ +extern int ext4_superblock_csum_verify(struct super_block *sb, + struct ext4_super_block *es); +extern void ext4_superblock_csum_set(struct super_block *sb, + struct ext4_super_block *es); extern void *ext4_kvmalloc(size_t size, gfp_t flags); extern void *ext4_kvzalloc(size_t size, gfp_t flags); extern void ext4_kvfree(void *ptr); @@ -2251,6 +2258,9 @@ static inline void ext4_unlock_group(struct super_block *sb, static inline void ext4_mark_super_dirty(struct super_block *sb) { + struct ext4_super_block *es = EXT4_SB(sb)->s_es; + + ext4_superblock_csum_set(sb, es); if (EXT4_SB(sb)->s_journal == NULL) sb->s_dirt =1; } diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c index aca1790..90f7c2e 100644 --- a/fs/ext4/ext4_jbd2.c +++ b/fs/ext4/ext4_jbd2.c @@ -138,16 +138,23 @@ int __ext4_handle_dirty_metadata(const char *where, unsigned int line, } int __ext4_handle_dirty_super(const char *where, unsigned int line, - handle_t *handle, struct super_block *sb) + handle_t *handle, struct super_block *sb, + int now) { struct buffer_head *bh = EXT4_SB(sb)->s_sbh; int err = 0; if (ext4_handle_valid(handle)) { + ext4_superblock_csum_set(sb, + (struct ext4_super_block *)bh->b_data); err = jbd2_journal_dirty_metadata(handle, bh); if (err) ext4_journal_abort_handle(where, line, __func__, bh, handle, err); + } else if (now) { + ext4_superblock_csum_set(sb, + (struct ext4_super_block *)bh->b_data); + mark_buffer_dirty(bh); } else sb->s_dirt = 1; return err; diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h index 5802fa1..ed9b78d 100644 --- a/fs/ext4/ext4_jbd2.h +++ b/fs/ext4/ext4_jbd2.h @@ -141,7 +141,8 @@ int __ext4_handle_dirty_metadata(const char *where, unsigned int line, struct buffer_head *bh); int __ext4_handle_dirty_super(const char *where, unsigned int line, - handle_t *handle, struct super_block *sb); + handle_t *handle, struct super_block *sb, + int now); #define ext4_journal_get_write_access(handle, bh) \ __ext4_journal_get_write_access(__func__, __LINE__, (handle), (bh)) @@ -153,8 +154,10 @@ int __ext4_handle_dirty_super(const char *where, unsigned int line, #define ext4_handle_dirty_metadata(handle, inode, bh) \ __ext4_handle_dirty_metadata(__func__, __LINE__, (handle), (inode), \ (bh)) +#define ext4_handle_dirty_super_now(handle, sb) \ + __ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb), 1) #define ext4_handle_dirty_super(handle, sb) \ - __ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb)) + __ext4_handle_dirty_super(__func__, __LINE__, (handle), (sb), 0) handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks); int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle); diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 92655fd..07cd63d 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4044,8 +4044,7 @@ static int ext4_do_update_inode(handle_t *handle, EXT4_FEATURE_RO_COMPAT_LARGE_FILE); sb->s_dirt = 1; ext4_handle_sync(handle); - err = ext4_handle_dirty_metadata(handle, NULL, - EXT4_SB(sb)->s_sbh); + err = ext4_handle_dirty_super_now(handle, sb); } } raw_inode->i_generation = cpu_to_le32(inode->i_generation); diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index c10ae34..ebfc499 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -2021,7 +2021,7 @@ int ext4_orphan_add(handle_t *handle, struct inode *inode) /* Insert this inode at the head of the on-disk orphan list... */ NEXT_ORPHAN(inode) = le32_to_cpu(EXT4_SB(sb)->s_es->s_last_orphan); EXT4_SB(sb)->s_es->s_last_orphan = cpu_to_le32(inode->i_ino); - err = ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh); + err = ext4_handle_dirty_super_now(handle, sb); rc = ext4_mark_iloc_dirty(handle, inode, &iloc); if (!err) err = rc; @@ -2094,7 +2094,7 @@ int ext4_orphan_del(handle_t *handle, struct inode *inode) if (err) goto out_brelse; sbi->s_es->s_last_orphan = cpu_to_le32(ino_next); - err = ext4_handle_dirty_metadata(handle, NULL, sbi->s_sbh); + err = ext4_handle_dirty_super_now(handle, inode->i_sb); } else { struct ext4_iloc iloc2; struct inode *i_prev = diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 996780a..c33b72a 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -511,7 +511,7 @@ static int add_new_gdb(handle_t *handle, struct inode *inode, ext4_kvfree(o_group_desc); le16_add_cpu(&es->s_reserved_gdt_blocks, -1); - err = ext4_handle_dirty_metadata(handle, NULL, EXT4_SB(sb)->s_sbh); + err = ext4_handle_dirty_super_now(handle, sb); if (err) ext4_std_error(sb, err); @@ -682,6 +682,8 @@ static void update_backups(struct super_block *sb, goto exit_err; } + ext4_superblock_csum_set(sb, (struct ext4_super_block *)data); + while ((group = ext4_list_backups(sb, &three, &five, &seven)) < last) { struct buffer_head *bh; @@ -925,6 +927,8 @@ int ext4_group_add(struct super_block *sb, struct ext4_new_group_data *input) /* Update the global fs size fields */ sbi->s_groups_count++; + ext4_superblock_csum_set(sb, + (struct ext4_super_block *)primary->b_data); err = ext4_handle_dirty_metadata(handle, NULL, primary); if (unlikely(err)) { ext4_std_error(sb, err); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 58c697f..99bee03 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -121,6 +121,38 @@ static int ext4_verify_csum_type(struct super_block *sb, return es->s_checksum_type == EXT4_CRC32C_CHKSUM; } +static __le32 ext4_superblock_csum(struct super_block *sb, + struct ext4_super_block *es) +{ + struct ext4_sb_info *sbi = EXT4_SB(sb); + int offset = offsetof(struct ext4_super_block, s_checksum); + __u32 csum; + + csum = ext4_chksum(sbi, ~0, (char *)es, offset); + + return cpu_to_le32(csum); +} + +int ext4_superblock_csum_verify(struct super_block *sb, + struct ext4_super_block *es) +{ + if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) + return 1; + + return es->s_checksum == ext4_superblock_csum(sb, es); +} + +void ext4_superblock_csum_set(struct super_block *sb, + struct ext4_super_block *es) +{ + if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) + return; + + es->s_checksum = ext4_superblock_csum(sb, es); +} + void *ext4_kvmalloc(size_t size, gfp_t flags) { void *ret; @@ -3213,6 +3245,20 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) } } + /* Check superblock checksum */ + if (!ext4_superblock_csum_verify(sb, es)) { + ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with " + "invalid superblock checksum. Run e2fsck?"); + silent = 1; + goto cantfind_ext4; + } + + /* Precompute checksum seed for all metadata */ + if (EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) + sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid, + sizeof(es->s_uuid)); + /* Set defaults before we parse the mount options */ def_mount_opts = le32_to_cpu(es->s_default_mount_opts); set_opt(sb, INIT_INODE_TABLE); @@ -4218,6 +4264,7 @@ static int ext4_commit_super(struct super_block *sb, int sync) &EXT4_SB(sb)->s_freeinodes_counter)); sb->s_dirt = 0; BUFFER_TRACE(sbh, "marking dirty"); + ext4_superblock_csum_set(sb, es); mark_buffer_dirty(sbh); if (sync) { error = sync_dirty_buffer(sbh);