From d25425f8e0ed01fc0167c043aee7e619fc3f6ab2 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 29 Apr 2012 18:25:10 -0400 Subject: ext4: record the checksum algorithm in use in the superblock Record the type of checksum algorithm we're using for metadata in the superblock, in case we ever want/need to change the algorithm. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index e1fb1d5de58e..f489ffb3605d 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -112,6 +112,16 @@ static struct file_system_type ext3_fs_type = { #define IS_EXT3_SB(sb) (0) #endif +static int ext4_verify_csum_type(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_type == EXT4_CRC32C_CHKSUM; +} + void *ext4_kvmalloc(size_t size, gfp_t flags) { void *ret; @@ -3025,6 +3035,14 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto cantfind_ext4; sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written); + /* Check for a known checksum algorithm */ + if (!ext4_verify_csum_type(sb, es)) { + ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with " + "unknown checksum algorithm."); + silent = 1; + goto cantfind_ext4; + } + /* 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); -- cgit v1.2.3 From 0441984a3398970ab4820410b9cf4ff85bf3a6b0 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 29 Apr 2012 18:27:10 -0400 Subject: ext4: load the crc32c driver if necessary Obtain a reference to the cryptoapi and crc32c if we mount a filesystem with metadata checksumming enabled. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index f489ffb3605d..11a0a7078da7 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -915,6 +915,8 @@ static void ext4_put_super(struct super_block *sb) unlock_super(sb); kobject_put(&sbi->s_kobj); wait_for_completion(&sbi->s_kobj_unregister); + if (sbi->s_chksum_driver) + crypto_free_shash(sbi->s_chksum_driver); kfree(sbi->s_blockgroup_lock); kfree(sbi); } @@ -3043,6 +3045,18 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto cantfind_ext4; } + /* Load the checksum driver */ + if (EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) { + sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0); + if (IS_ERR(sbi->s_chksum_driver)) { + ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver."); + ret = PTR_ERR(sbi->s_chksum_driver); + sbi->s_chksum_driver = NULL; + goto failed_mount; + } + } + /* 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); @@ -3728,6 +3742,8 @@ failed_mount2: brelse(sbi->s_group_desc[i]); ext4_kvfree(sbi->s_group_desc); failed_mount: + if (sbi->s_chksum_driver) + crypto_free_shash(sbi->s_chksum_driver); if (sbi->s_proc) { remove_proc_entry("options", sbi->s_proc); remove_proc_entry(sb->s_id, ext4_proc_root); -- cgit v1.2.3 From a9c4731780544d52b243bf46e4dd635c67fa9f84 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 29 Apr 2012 18:29:10 -0400 Subject: ext4: calculate and verify superblock checksum 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 Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 11a0a7078da7..f80c7e612829 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -122,6 +122,38 @@ 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; @@ -3057,6 +3089,20 @@ 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); @@ -4059,6 +4105,7 @@ 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); -- cgit v1.2.3 From feb0ab32a57e4e6c8b24f6fb68f0ce08efe4603c Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 29 Apr 2012 18:45:10 -0400 Subject: ext4: make block group checksums use metadata_csum algorithm metadata_csum supersedes uninit_bg. Convert the ROCOMPAT uninit_bg flag check to a helper function that covers both, and make the checksum calculation algorithm use either crc16 or the metadata_csum chosen algorithm depending on which flag is set. Print a warning if we try to mount a filesystem with both feature flags set. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 81 ++++++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 57 insertions(+), 24 deletions(-) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index f80c7e612829..c18c5968cd96 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1952,43 +1952,69 @@ failed: return 0; } -__le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group, - struct ext4_group_desc *gdp) +static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group, + struct ext4_group_desc *gdp) { + int offset; __u16 crc = 0; + __le32 le_group = cpu_to_le32(block_group); - if (sbi->s_es->s_feature_ro_compat & - cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) { - int offset = offsetof(struct ext4_group_desc, bg_checksum); - __le32 le_group = cpu_to_le32(block_group); - - crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid)); - crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group)); - crc = crc16(crc, (__u8 *)gdp, offset); - offset += sizeof(gdp->bg_checksum); /* skip checksum */ - /* for checksum of struct ext4_group_desc do the rest...*/ - if ((sbi->s_es->s_feature_incompat & - cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) && - offset < le16_to_cpu(sbi->s_es->s_desc_size)) - crc = crc16(crc, (__u8 *)gdp + offset, - le16_to_cpu(sbi->s_es->s_desc_size) - - offset); + if ((sbi->s_es->s_feature_ro_compat & + cpu_to_le32(EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))) { + /* Use new metadata_csum algorithm */ + __u16 old_csum; + __u32 csum32; + + old_csum = gdp->bg_checksum; + gdp->bg_checksum = 0; + csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group, + sizeof(le_group)); + csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, + sbi->s_desc_size); + gdp->bg_checksum = old_csum; + + crc = csum32 & 0xFFFF; + goto out; } + /* old crc16 code */ + offset = offsetof(struct ext4_group_desc, bg_checksum); + + crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid)); + crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group)); + crc = crc16(crc, (__u8 *)gdp, offset); + offset += sizeof(gdp->bg_checksum); /* skip checksum */ + /* for checksum of struct ext4_group_desc do the rest...*/ + if ((sbi->s_es->s_feature_incompat & + cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) && + offset < le16_to_cpu(sbi->s_es->s_desc_size)) + crc = crc16(crc, (__u8 *)gdp + offset, + le16_to_cpu(sbi->s_es->s_desc_size) - + offset); + +out: return cpu_to_le16(crc); } -int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group, +int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group, struct ext4_group_desc *gdp) { - if ((sbi->s_es->s_feature_ro_compat & - cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) && - (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp))) + if (ext4_has_group_desc_csum(sb) && + (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb), + block_group, gdp))) return 0; return 1; } +void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group, + struct ext4_group_desc *gdp) +{ + if (!ext4_has_group_desc_csum(sb)) + return; + gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp); +} + /* Called at mount-time, super-block is locked */ static int ext4_check_descriptors(struct super_block *sb, ext4_group_t *first_not_zeroed) @@ -2043,7 +2069,7 @@ static int ext4_check_descriptors(struct super_block *sb, return 0; } ext4_lock_group(sb, i); - if (!ext4_group_desc_csum_verify(sbi, i, gdp)) { + if (!ext4_group_desc_csum_verify(sb, i, gdp)) { ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: " "Checksum for group %u failed (%u!=%u)", i, le16_to_cpu(ext4_group_desc_csum(sbi, i, @@ -3069,6 +3095,13 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto cantfind_ext4; sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written); + /* Warn if metadata_csum and gdt_csum are both set. */ + if (EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) && + EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) + ext4_warning(sb, KERN_INFO "metadata_csum and uninit_bg are " + "redundant flags; please run fsck."); + /* Check for a known checksum algorithm */ if (!ext4_verify_csum_type(sb, es)) { ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with " @@ -4400,7 +4433,7 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) struct ext4_group_desc *gdp = ext4_get_group_desc(sb, g, NULL); - if (!ext4_group_desc_csum_verify(sbi, g, gdp)) { + if (!ext4_group_desc_csum_verify(sb, g, gdp)) { ext4_msg(sb, KERN_ERR, "ext4_remount: Checksum for group %u failed (%u!=%u)", g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)), -- cgit v1.2.3 From f32aaf2d2b996b14e993da1c23f7ee22ea7333a3 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Mon, 21 May 2012 11:42:02 -0400 Subject: ext4: enable the 64-bit jbd2 feature based on the 64-bit ext4 feature Previously we were only enabling the 64-bit jbd2 feature if the number of blocks in the file system was greater 2**32-1. The problem with this is that it makes it harder to test the 64-bit journal code paths with small file systems, since a small test file system would with the 64-bit ext4 feature enable would use a 64-bit file system on-disk data structures, but use a 32-bit journal. This would also cause problems when trying to do an online resize to grow the filesystem above the 2**32-1 boundary. Fortunately the patch to support online resize for 64-bit file systems hasn't been merged yet, so this problem hasn't arisen in practice. Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index c18c5968cd96..88c2054fb938 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3603,7 +3603,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto no_journal; } - if (ext4_blocks_count(es) > 0xffffffffULL && + if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) && !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_64BIT)) { ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature"); -- cgit v1.2.3 From 25ed6e8a54df904c875365eebedbd19138a47328 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 27 May 2012 07:48:56 -0400 Subject: jbd2: enable journal clients to enable v2 checksumming Add in the necessary code so that journal clients can enable the new journal checksumming features. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 55 ++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 42 insertions(+), 13 deletions(-) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 88c2054fb938..8dfb42e380ea 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3013,6 +3013,44 @@ static void ext4_destroy_lazyinit_thread(void) kthread_stop(ext4_lazyinit_task); } +static int set_journal_csum_feature_set(struct super_block *sb) +{ + int ret = 1; + int compat, incompat; + struct ext4_sb_info *sbi = EXT4_SB(sb); + + if (EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) { + /* journal checksum v2 */ + compat = 0; + incompat = JBD2_FEATURE_INCOMPAT_CSUM_V2; + } else { + /* journal checksum v1 */ + compat = JBD2_FEATURE_COMPAT_CHECKSUM; + incompat = 0; + } + + if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) { + ret = jbd2_journal_set_features(sbi->s_journal, + compat, 0, + JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | + incompat); + } else if (test_opt(sb, JOURNAL_CHECKSUM)) { + ret = jbd2_journal_set_features(sbi->s_journal, + compat, 0, + incompat); + jbd2_journal_clear_features(sbi->s_journal, 0, 0, + JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT); + } else { + jbd2_journal_clear_features(sbi->s_journal, + JBD2_FEATURE_COMPAT_CHECKSUM, 0, + JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT | + JBD2_FEATURE_INCOMPAT_CSUM_V2); + } + + return ret; +} + static int ext4_fill_super(struct super_block *sb, void *data, int silent) { char *orig_data = kstrdup(data, GFP_KERNEL); @@ -3610,19 +3648,10 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto failed_mount_wq; } - if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) { - jbd2_journal_set_features(sbi->s_journal, - JBD2_FEATURE_COMPAT_CHECKSUM, 0, - JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT); - } else if (test_opt(sb, JOURNAL_CHECKSUM)) { - jbd2_journal_set_features(sbi->s_journal, - JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0); - jbd2_journal_clear_features(sbi->s_journal, 0, 0, - JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT); - } else { - jbd2_journal_clear_features(sbi->s_journal, - JBD2_FEATURE_COMPAT_CHECKSUM, 0, - JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT); + if (!set_journal_csum_feature_set(sb)) { + ext4_msg(sb, KERN_ERR, "Failed to set journal checksum " + "feature set"); + goto failed_mount_wq; } /* We have now updated the journal if required, so we can -- cgit v1.2.3 From 7e84b6216467b84cd332c8e567bf5aa113fd2f38 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Mon, 28 May 2012 14:17:25 -0400 Subject: ext4: force ro mount if ext4_setup_super() fails If ext4_setup_super() fails i.e. due to a too-high revision, the error is logged in dmesg but the fs is not mounted RO as indicated. Tested by: # mkfs.ext4 -r 4 /dev/sdb6 # mount /dev/sdb6 /mnt/test # dmesg | grep "too high" [164919.759248] EXT4-fs (sdb6): revision level too high, forcing read-only mode # grep sdb6 /proc/mounts /dev/sdb6 /mnt/test2 ext4 rw,seclabel,relatime,data=ordered 0 0 Reviewed-by: Andreas Dilger Signed-off-by: Eric Sandeen Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org --- fs/ext4/super.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 8dfb42e380ea..d9466a508414 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3732,7 +3732,8 @@ no_journal: goto failed_mount4; } - ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY); + if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY)) + sb->s_flags |= MS_RDONLY; /* determine the minimum size of new large inodes, if present */ if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) { -- cgit v1.2.3 From 9d99012ff26380a09092a9fddbb6e5f996dc631f Mon Sep 17 00:00:00 2001 From: Akira Fujita Date: Mon, 28 May 2012 14:19:25 -0400 Subject: ext4: remove needs_recovery in ext4_mb_init() needs_recovery in ext4_mb_init() is not used, remove it. Signed-off-by: Akira Fujita Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index d9466a508414..dbc9544c7087 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3768,7 +3768,7 @@ no_journal: } ext4_ext_init(sb); - err = ext4_mb_init(sb, needs_recovery); + err = ext4_mb_init(sb); if (err) { ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)", err); -- cgit v1.2.3 From 2716b80284c5ca415b8ce93ca178b0ca28482568 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Mon, 28 May 2012 17:47:52 -0400 Subject: ext4: remove redundundant "(char *) bh->b_data" casts The b_data field of the buffer_head is already a char *, so there's no point casting it to a char *. Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index dbc9544c7087..545932c0a290 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3126,7 +3126,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) * Note: s_es must be initialized as soon as possible because * some ext4 macro-instructions depend on its value */ - es = (struct ext4_super_block *) (((char *)bh->b_data) + offset); + es = (struct ext4_super_block *) (bh->b_data + offset); sbi->s_es = es; sb->s_magic = le16_to_cpu(es->s_magic); if (sb->s_magic != EXT4_SUPER_MAGIC) @@ -3335,7 +3335,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) "Can't read superblock on 2nd try"); goto failed_mount; } - es = (struct ext4_super_block *)(((char *)bh->b_data) + offset); + es = (struct ext4_super_block *)(bh->b_data + offset); sbi->s_es = es; if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) { ext4_msg(sb, KERN_ERR, @@ -3976,7 +3976,7 @@ static journal_t *ext4_get_dev_journal(struct super_block *sb, goto out_bdev; } - es = (struct ext4_super_block *) (((char *)bh->b_data) + offset); + es = (struct ext4_super_block *) (bh->b_data + offset); if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) || !(le32_to_cpu(es->s_feature_incompat) & EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) { -- cgit v1.2.3 From 2cde417de013b2e5ae3007374d937e8c4c426bd4 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Mon, 28 May 2012 17:49:54 -0400 Subject: ext4: return ENOMEM when mounts fail due to lack of memory This is a port of the ext3 commit: 4569cd1b0d9 Signed-off-by: "Theodore Ts'o" --- fs/ext4/super.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 545932c0a290..628cfcdc0823 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3527,6 +3527,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) GFP_KERNEL); if (sbi->s_group_desc == NULL) { ext4_msg(sb, KERN_ERR, "not enough memory"); + ret = -ENOMEM; goto failed_mount; } @@ -3584,6 +3585,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) } if (err) { ext4_msg(sb, KERN_ERR, "insufficient memory"); + ret = err; goto failed_mount3; } -- cgit v1.2.3 From 2c0544b23568674efba22532e1f25fb62ce10163 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Wed, 30 May 2012 22:56:46 -0400 Subject: ext4: add debugging trigger for ext4_error() Make it easy to test whether or not the error handling subsystem in ext4 is working correctly. This allows us to simulate an ext4_error() by echoing a string to /sys/fs/ext4//trigger_fs_error. Signed-off-by: "Theodore Ts'o" Cc: ksumrall@google.com --- fs/ext4/super.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 628cfcdc0823..9f1ae6b36502 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2473,6 +2473,23 @@ static ssize_t sbi_ui_store(struct ext4_attr *a, return count; } +static ssize_t trigger_test_error(struct ext4_attr *a, + struct ext4_sb_info *sbi, + const char *buf, size_t count) +{ + int len = count; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (len && buf[len-1] == '\n') + len--; + + if (len) + ext4_error(sbi->s_sb, "%.*s", len, buf); + return count; +} + #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \ static struct ext4_attr ext4_attr_##_name = { \ .attr = {.name = __stringify(_name), .mode = _mode }, \ @@ -2503,6 +2520,7 @@ EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs); EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request); EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc); EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump); +EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error); static struct attribute *ext4_attrs[] = { ATTR_LIST(delayed_allocation_blocks), @@ -2517,6 +2535,7 @@ static struct attribute *ext4_attrs[] = { ATTR_LIST(mb_stream_req), ATTR_LIST(mb_group_prealloc), ATTR_LIST(max_writeback_mb_bump), + ATTR_LIST(trigger_fs_error), NULL, }; @@ -3087,6 +3106,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto out_free_orig; } sb->s_fs_info = sbi; + sbi->s_sb = sb; sbi->s_mount_opt = 0; sbi->s_resuid = EXT4_DEF_RESUID; sbi->s_resgid = EXT4_DEF_RESGID; -- cgit v1.2.3 From f3fc0210c0fc91900766c995f089c39170e68305 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Wed, 30 May 2012 23:00:16 -0400 Subject: ext4: add missing save_error_info() to ext4_error() The ext4_error() function is missing a call to save_error_info(). Since this is the function which marks the file system as containing an error, this oversight (which was introduced in 2.6.36) is quite significant, and should be backported to older stable kernels with high urgency. Reported-by: Ken Sumrall Signed-off-by: "Theodore Ts'o" Cc: ksumrall@google.com Cc: stable@kernel.org --- fs/ext4/super.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/ext4/super.c') diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 9f1ae6b36502..b8d5fc10d8c0 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -539,6 +539,7 @@ void __ext4_error(struct super_block *sb, const char *function, printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n", sb->s_id, function, line, current->comm, &vaf); va_end(args); + save_error_info(sb, function, line); ext4_handle_error(sb); } -- cgit v1.2.3