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/resize.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'fs/ext4/resize.c') diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 59fa0be27251..e0374757a94b 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -796,7 +796,7 @@ 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); @@ -968,6 +968,8 @@ 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; -- cgit v1.2.3 From 41a246d1ff75a95d2be3191ca6e6db139dc0f430 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 29 Apr 2012 18:33:10 -0400 Subject: ext4: calculate and verify checksums for inode bitmaps Compute and verify the checksum of the inode bitmap; the checkum is stored in the block group descriptor. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o" --- fs/ext4/bitmap.c | 39 +++++++++++++++++++++++++++++++++++++++ fs/ext4/ext4.h | 20 ++++++++++++++++++++ fs/ext4/ialloc.c | 34 +++++++++++++++++++++++++++++----- fs/ext4/resize.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 135 insertions(+), 5 deletions(-) (limited to 'fs/ext4/resize.c') diff --git a/fs/ext4/bitmap.c b/fs/ext4/bitmap.c index fa3af81ac565..5813e7f2e2c6 100644 --- a/fs/ext4/bitmap.c +++ b/fs/ext4/bitmap.c @@ -29,3 +29,42 @@ unsigned int ext4_count_free(struct buffer_head *map, unsigned int numchars) #endif /* EXT4FS_DEBUG */ +int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group, + struct ext4_group_desc *gdp, + struct buffer_head *bh, int sz) +{ + __u32 hi; + __u32 provided, calculated; + struct ext4_sb_info *sbi = EXT4_SB(sb); + + if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) + return 1; + + provided = le16_to_cpu(gdp->bg_inode_bitmap_csum_lo); + calculated = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz); + if (sbi->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END) { + hi = le16_to_cpu(gdp->bg_inode_bitmap_csum_hi); + provided |= (hi << 16); + } else + calculated &= 0xFFFF; + + return provided == calculated; +} + +void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group, + struct ext4_group_desc *gdp, + struct buffer_head *bh, int sz) +{ + __u32 csum; + struct ext4_sb_info *sbi = EXT4_SB(sb); + + if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) + return; + + csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz); + gdp->bg_inode_bitmap_csum_lo = cpu_to_le16(csum & 0xFFFF); + if (sbi->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END) + gdp->bg_inode_bitmap_csum_hi = cpu_to_le16(csum >> 16); +} diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index ca96401b4b81..7f0ff88f32ba 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -317,6 +317,13 @@ struct ext4_group_desc __u32 bg_reserved; }; +#define EXT4_BG_INODE_BITMAP_CSUM_HI_END \ + (offsetof(struct ext4_group_desc, bg_inode_bitmap_csum_hi) + \ + sizeof(__le16)) +#define EXT4_BG_BLOCK_BITMAP_CSUM_HI_END \ + (offsetof(struct ext4_group_desc, bg_block_bitmap_csum_hi) + \ + sizeof(__le16)) + /* * Structure of a flex block group info */ @@ -1844,6 +1851,12 @@ struct mmpd_data { /* bitmap.c */ extern unsigned int ext4_count_free(struct buffer_head *, unsigned); +void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group, + struct ext4_group_desc *gdp, + struct buffer_head *bh, int sz); +int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group, + struct ext4_group_desc *gdp, + struct buffer_head *bh, int sz); /* balloc.c */ extern unsigned int ext4_block_group(struct super_block *sb, @@ -2094,6 +2107,13 @@ extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group, extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group, struct ext4_group_desc *gdp); +static inline int ext4_has_group_desc_csum(struct super_block *sb) +{ + return EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_GDT_CSUM | + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM); +} + static inline ext4_fsblk_t ext4_blocks_count(struct ext4_super_block *es) { return ((ext4_fsblk_t)le32_to_cpu(es->s_blocks_count_hi) << 32) | diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index 8207dfab2682..fb897ec183c8 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -82,12 +82,17 @@ static unsigned ext4_init_inode_bitmap(struct super_block *sb, ext4_free_inodes_set(sb, gdp, 0); ext4_itable_unused_set(sb, gdp, 0); memset(bh->b_data, 0xff, sb->s_blocksize); + ext4_inode_bitmap_csum_set(sb, block_group, gdp, bh, + EXT4_INODES_PER_GROUP(sb) / 8); return 0; } memset(bh->b_data, 0, (EXT4_INODES_PER_GROUP(sb) + 7) / 8); ext4_mark_bitmap_end(EXT4_INODES_PER_GROUP(sb), sb->s_blocksize * 8, bh->b_data); + ext4_inode_bitmap_csum_set(sb, block_group, gdp, bh, + EXT4_INODES_PER_GROUP(sb) / 8); + gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); return EXT4_INODES_PER_GROUP(sb); } @@ -128,12 +133,12 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group) return NULL; } if (bitmap_uptodate(bh)) - return bh; + goto verify; lock_buffer(bh); if (bitmap_uptodate(bh)) { unlock_buffer(bh); - return bh; + goto verify; } ext4_lock_group(sb, block_group); @@ -141,6 +146,7 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group) ext4_init_inode_bitmap(sb, bh, block_group, desc); set_bitmap_uptodate(bh); set_buffer_uptodate(bh); + set_buffer_verified(bh); ext4_unlock_group(sb, block_group); unlock_buffer(bh); return bh; @@ -154,7 +160,7 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group) */ set_bitmap_uptodate(bh); unlock_buffer(bh); - return bh; + goto verify; } /* * submit the buffer_head for reading @@ -171,6 +177,20 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group) block_group, bitmap_blk); return NULL; } + +verify: + ext4_lock_group(sb, block_group); + if (!buffer_verified(bh) && + !ext4_inode_bitmap_csum_verify(sb, block_group, desc, bh, + EXT4_INODES_PER_GROUP(sb) / 8)) { + ext4_unlock_group(sb, block_group); + put_bh(bh); + ext4_error(sb, "Corrupt inode bitmap - block_group = %u, " + "inode_bitmap = %llu", block_group, bitmap_blk); + return NULL; + } + ext4_unlock_group(sb, block_group); + set_buffer_verified(bh); return bh; } @@ -276,6 +296,8 @@ void ext4_free_inode(handle_t *handle, struct inode *inode) ext4_used_dirs_set(sb, gdp, count); percpu_counter_dec(&sbi->s_dirs_counter); } + ext4_inode_bitmap_csum_set(sb, block_group, gdp, bitmap_bh, + EXT4_INODES_PER_GROUP(sb) / 8); gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); ext4_unlock_group(sb, block_group); @@ -751,7 +773,7 @@ got: goto fail; /* Update the relevant bg descriptor fields */ - if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) { + if (ext4_has_group_desc_csum(sb)) { int free; struct ext4_group_info *grp = ext4_get_group_info(sb, group); @@ -782,7 +804,9 @@ got: atomic_inc(&sbi->s_flex_groups[f].used_dirs); } } - if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) { + if (ext4_has_group_desc_csum(sb)) { + ext4_inode_bitmap_csum_set(sb, group, gdp, inode_bitmap_bh, + EXT4_INODES_PER_GROUP(sb) / 8); gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); ext4_unlock_group(sb, group); } diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index e0374757a94b..7810cac241e1 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1069,6 +1069,47 @@ static int ext4_add_new_descs(handle_t *handle, struct super_block *sb, return err; } +static struct buffer_head *ext4_get_bitmap(struct super_block *sb, __u64 block) +{ + struct buffer_head *bh = sb_getblk(sb, block); + if (!bh) + return NULL; + + if (bitmap_uptodate(bh)) + return bh; + + lock_buffer(bh); + if (bh_submit_read(bh) < 0) { + unlock_buffer(bh); + brelse(bh); + return NULL; + } + unlock_buffer(bh); + + return bh; +} + +static int ext4_set_bitmap_checksums(struct super_block *sb, + ext4_group_t group, + struct ext4_group_desc *gdp, + struct ext4_new_group_data *group_data) +{ + struct buffer_head *bh; + + if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) + return 0; + + bh = ext4_get_bitmap(sb, group_data->inode_bitmap); + if (!bh) + return -EIO; + ext4_inode_bitmap_csum_set(sb, group, gdp, bh, + EXT4_INODES_PER_GROUP(sb) / 8); + brelse(bh); + + return 0; +} + /* * ext4_setup_new_descs() will set up the group descriptor descriptors of a flex bg */ @@ -1101,6 +1142,12 @@ static int ext4_setup_new_descs(handle_t *handle, struct super_block *sb, memset(gdp, 0, EXT4_DESC_SIZE(sb)); ext4_block_bitmap_set(sb, gdp, group_data->block_bitmap); ext4_inode_bitmap_set(sb, gdp, group_data->inode_bitmap); + err = ext4_set_bitmap_checksums(sb, group, gdp, group_data); + if (err) { + ext4_std_error(sb, err); + break; + } + ext4_inode_table_set(sb, gdp, group_data->inode_table); ext4_free_group_clusters_set(sb, gdp, EXT4_B2C(sbi, group_data->free_blocks_count)); -- cgit v1.2.3 From fa77dcfafeaa6bc73293c646bfc3d5192dcf0be2 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 29 Apr 2012 18:35:10 -0400 Subject: ext4: calculate and verify block bitmap checksum Compute and verify the checksum of the block bitmap; this checksum is stored in the block group descriptor. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o" --- fs/ext4/balloc.c | 39 ++++++++++++++++++++++++++++++++------- fs/ext4/bitmap.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ fs/ext4/ext4.h | 10 ++++++++++ fs/ext4/ialloc.c | 4 ++++ fs/ext4/mballoc.c | 8 +++++++- fs/ext4/resize.c | 7 +++++++ 6 files changed, 104 insertions(+), 8 deletions(-) (limited to 'fs/ext4/resize.c') diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 4bbd07a6fa18..0a64e4d5dbad 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -174,6 +174,8 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, ext4_free_inodes_set(sb, gdp, 0); ext4_itable_unused_set(sb, gdp, 0); memset(bh->b_data, 0xff, sb->s_blocksize); + ext4_block_bitmap_csum_set(sb, block_group, gdp, bh, + EXT4_BLOCKS_PER_GROUP(sb) / 8); return; } memset(bh->b_data, 0, sb->s_blocksize); @@ -210,6 +212,9 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, */ ext4_mark_bitmap_end(num_clusters_in_group(sb, block_group), sb->s_blocksize * 8, bh->b_data); + ext4_block_bitmap_csum_set(sb, block_group, gdp, bh, + EXT4_BLOCKS_PER_GROUP(sb) / 8); + gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); } /* Return the number of free blocks in a block group. It is used when @@ -276,9 +281,9 @@ struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb, } static int ext4_valid_block_bitmap(struct super_block *sb, - struct ext4_group_desc *desc, - unsigned int block_group, - struct buffer_head *bh) + struct ext4_group_desc *desc, + unsigned int block_group, + struct buffer_head *bh) { ext4_grpblk_t offset; ext4_grpblk_t next_zero_bit; @@ -325,6 +330,23 @@ err_out: block_group, bitmap_blk); return 0; } + +void ext4_validate_block_bitmap(struct super_block *sb, + struct ext4_group_desc *desc, + unsigned int block_group, + struct buffer_head *bh) +{ + if (buffer_verified(bh)) + return; + + ext4_lock_group(sb, block_group); + if (ext4_valid_block_bitmap(sb, desc, block_group, bh) && + ext4_block_bitmap_csum_verify(sb, block_group, desc, bh, + EXT4_BLOCKS_PER_GROUP(sb) / 8)) + set_buffer_verified(bh); + ext4_unlock_group(sb, block_group); +} + /** * ext4_read_block_bitmap() * @sb: super block @@ -355,12 +377,12 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group) } if (bitmap_uptodate(bh)) - return bh; + goto verify; lock_buffer(bh); if (bitmap_uptodate(bh)) { unlock_buffer(bh); - return bh; + goto verify; } ext4_lock_group(sb, block_group); if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { @@ -379,7 +401,7 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group) */ set_bitmap_uptodate(bh); unlock_buffer(bh); - return bh; + goto verify; } /* * submit the buffer_head for reading @@ -390,6 +412,9 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group) get_bh(bh); submit_bh(READ, bh); return bh; +verify: + ext4_validate_block_bitmap(sb, desc, block_group, bh); + return bh; } /* Returns 0 on success, 1 on error */ @@ -412,7 +437,7 @@ int ext4_wait_block_bitmap(struct super_block *sb, ext4_group_t block_group, } clear_buffer_new(bh); /* Panic or remount fs read-only if block bitmap is invalid */ - ext4_valid_block_bitmap(sb, desc, block_group, bh); + ext4_validate_block_bitmap(sb, desc, block_group, bh); return 0; } diff --git a/fs/ext4/bitmap.c b/fs/ext4/bitmap.c index 5813e7f2e2c6..b319721da26a 100644 --- a/fs/ext4/bitmap.c +++ b/fs/ext4/bitmap.c @@ -68,3 +68,47 @@ void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group, if (sbi->s_desc_size >= EXT4_BG_INODE_BITMAP_CSUM_HI_END) gdp->bg_inode_bitmap_csum_hi = cpu_to_le16(csum >> 16); } + +int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group, + struct ext4_group_desc *gdp, + struct buffer_head *bh, int sz) +{ + __u32 hi; + __u32 provided, calculated; + struct ext4_sb_info *sbi = EXT4_SB(sb); + + if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) + return 1; + + provided = le16_to_cpu(gdp->bg_block_bitmap_csum_lo); + calculated = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz); + if (sbi->s_desc_size >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_END) { + hi = le16_to_cpu(gdp->bg_block_bitmap_csum_hi); + provided |= (hi << 16); + } else + calculated &= 0xFFFF; + + if (provided == calculated) + return 1; + + ext4_error(sb, "Bad block bitmap checksum: block_group = %u", group); + return 0; +} + +void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group, + struct ext4_group_desc *gdp, + struct buffer_head *bh, int sz) +{ + __u32 csum; + struct ext4_sb_info *sbi = EXT4_SB(sb); + + if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, + EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) + return; + + csum = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)bh->b_data, sz); + gdp->bg_block_bitmap_csum_lo = cpu_to_le16(csum & 0xFFFF); + if (sbi->s_desc_size >= EXT4_BG_BLOCK_BITMAP_CSUM_HI_END) + gdp->bg_block_bitmap_csum_hi = cpu_to_le16(csum >> 16); +} diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 7f0ff88f32ba..7a4f16075257 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1857,8 +1857,18 @@ void ext4_inode_bitmap_csum_set(struct super_block *sb, ext4_group_t group, int ext4_inode_bitmap_csum_verify(struct super_block *sb, ext4_group_t group, struct ext4_group_desc *gdp, struct buffer_head *bh, int sz); +void ext4_block_bitmap_csum_set(struct super_block *sb, ext4_group_t group, + struct ext4_group_desc *gdp, + struct buffer_head *bh, int sz); +int ext4_block_bitmap_csum_verify(struct super_block *sb, ext4_group_t group, + struct ext4_group_desc *gdp, + struct buffer_head *bh, int sz); /* balloc.c */ +extern void ext4_validate_block_bitmap(struct super_block *sb, + struct ext4_group_desc *desc, + unsigned int block_group, + struct buffer_head *bh); extern unsigned int ext4_block_group(struct super_block *sb, ext4_fsblk_t blocknr); extern ext4_grpblk_t ext4_block_group_offset(struct super_block *sb, diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index fb897ec183c8..a6383fcb714b 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -753,6 +753,10 @@ got: gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT); ext4_free_group_clusters_set(sb, gdp, ext4_free_clusters_after_init(sb, group, gdp)); + ext4_block_bitmap_csum_set(sb, group, gdp, + block_bitmap_bh, + EXT4_BLOCKS_PER_GROUP(sb) / + 8); gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); } diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 99ab428bcfa0..95a388fef397 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -788,7 +788,7 @@ static int ext4_mb_init_cache(struct page *page, char *incore) int first_block; struct super_block *sb; struct buffer_head *bhs; - struct buffer_head **bh; + struct buffer_head **bh = NULL; struct inode *inode; char *data; char *bitmap; @@ -2797,6 +2797,8 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac, } len = ext4_free_group_clusters(sb, gdp) - ac->ac_b_ex.fe_len; ext4_free_group_clusters_set(sb, gdp, len); + ext4_block_bitmap_csum_set(sb, ac->ac_b_ex.fe_group, gdp, bitmap_bh, + EXT4_BLOCKS_PER_GROUP(sb) / 8); gdp->bg_checksum = ext4_group_desc_csum(sbi, ac->ac_b_ex.fe_group, gdp); ext4_unlock_group(sb, ac->ac_b_ex.fe_group); @@ -4659,6 +4661,8 @@ do_more: ret = ext4_free_group_clusters(sb, gdp) + count_clusters; ext4_free_group_clusters_set(sb, gdp, ret); + ext4_block_bitmap_csum_set(sb, block_group, gdp, bitmap_bh, + EXT4_BLOCKS_PER_GROUP(sb) / 8); gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); ext4_unlock_group(sb, block_group); percpu_counter_add(&sbi->s_freeclusters_counter, count_clusters); @@ -4803,6 +4807,8 @@ int ext4_group_add_blocks(handle_t *handle, struct super_block *sb, mb_free_blocks(NULL, &e4b, bit, count); blk_free_count = blocks_freed + ext4_free_group_clusters(sb, desc); ext4_free_group_clusters_set(sb, desc, blk_free_count); + ext4_block_bitmap_csum_set(sb, block_group, desc, bitmap_bh, + EXT4_BLOCKS_PER_GROUP(sb) / 8); desc->bg_checksum = ext4_group_desc_csum(sbi, block_group, desc); ext4_unlock_group(sb, block_group); percpu_counter_add(&sbi->s_freeclusters_counter, diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 7810cac241e1..dc597e066308 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1107,6 +1107,13 @@ static int ext4_set_bitmap_checksums(struct super_block *sb, EXT4_INODES_PER_GROUP(sb) / 8); brelse(bh); + bh = ext4_get_bitmap(sb, group_data->block_bitmap); + if (!bh) + return -EIO; + ext4_block_bitmap_csum_set(sb, group, gdp, bh, + EXT4_BLOCKS_PER_GROUP(sb) / 8); + brelse(bh); + return 0; } -- 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/balloc.c | 4 +-- fs/ext4/ext4.h | 6 ++--- fs/ext4/ialloc.c | 17 +++++------- fs/ext4/inode.c | 3 +-- fs/ext4/mballoc.c | 6 ++--- fs/ext4/resize.c | 9 +++---- fs/ext4/super.c | 81 ++++++++++++++++++++++++++++++++++++++----------------- 7 files changed, 76 insertions(+), 50 deletions(-) (limited to 'fs/ext4/resize.c') diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 0a64e4d5dbad..5745d53c67e8 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -168,7 +168,7 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, /* If checksum is bad mark all blocks used to prevent allocation * essentially implementing a per-group read-only flag. */ - if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) { + if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) { ext4_error(sb, "Checksum bad for group %u", block_group); ext4_free_group_clusters_set(sb, gdp, 0); ext4_free_inodes_set(sb, gdp, 0); @@ -214,7 +214,7 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh, sb->s_blocksize * 8, bh->b_data); ext4_block_bitmap_csum_set(sb, block_group, gdp, bh, EXT4_BLOCKS_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); + ext4_group_desc_csum_set(sb, block_group, gdp); } /* Return the number of free blocks in a block group. It is used when diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 57d7c356eaab..84e76bb96070 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2114,10 +2114,10 @@ extern void ext4_used_dirs_set(struct super_block *sb, struct ext4_group_desc *bg, __u32 count); extern void ext4_itable_unused_set(struct super_block *sb, struct ext4_group_desc *bg, __u32 count); -extern __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 group, - struct ext4_group_desc *gdp); -extern int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 group, +extern int ext4_group_desc_csum_verify(struct super_block *sb, __u32 group, struct ext4_group_desc *gdp); +extern void ext4_group_desc_csum_set(struct super_block *sb, __u32 group, + struct ext4_group_desc *gdp); static inline int ext4_has_group_desc_csum(struct super_block *sb) { diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index a6383fcb714b..a044a9b77491 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -70,13 +70,11 @@ static unsigned ext4_init_inode_bitmap(struct super_block *sb, ext4_group_t block_group, struct ext4_group_desc *gdp) { - struct ext4_sb_info *sbi = EXT4_SB(sb); - J_ASSERT_BH(bh, buffer_locked(bh)); /* If checksum is bad mark all blocks and inodes use to prevent * allocation, essentially implementing a per-group read-only flag. */ - if (!ext4_group_desc_csum_verify(sbi, block_group, gdp)) { + if (!ext4_group_desc_csum_verify(sb, block_group, gdp)) { ext4_error(sb, "Checksum bad for group %u", block_group); ext4_free_group_clusters_set(sb, gdp, 0); ext4_free_inodes_set(sb, gdp, 0); @@ -92,7 +90,7 @@ static unsigned ext4_init_inode_bitmap(struct super_block *sb, bh->b_data); ext4_inode_bitmap_csum_set(sb, block_group, gdp, bh, EXT4_INODES_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); + ext4_group_desc_csum_set(sb, block_group, gdp); return EXT4_INODES_PER_GROUP(sb); } @@ -298,7 +296,7 @@ void ext4_free_inode(handle_t *handle, struct inode *inode) } ext4_inode_bitmap_csum_set(sb, block_group, gdp, bitmap_bh, EXT4_INODES_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); + ext4_group_desc_csum_set(sb, block_group, gdp); ext4_unlock_group(sb, block_group); percpu_counter_inc(&sbi->s_freeinodes_counter); @@ -731,7 +729,7 @@ repeat_in_this_group: got: /* We may have to initialize the block bitmap if it isn't already */ - if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM) && + if (ext4_has_group_desc_csum(sb) && gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { struct buffer_head *block_bitmap_bh; @@ -757,8 +755,7 @@ got: block_bitmap_bh, EXT4_BLOCKS_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, group, - gdp); + ext4_group_desc_csum_set(sb, group, gdp); } ext4_unlock_group(sb, group); @@ -811,7 +808,7 @@ got: if (ext4_has_group_desc_csum(sb)) { ext4_inode_bitmap_csum_set(sb, group, gdp, inode_bitmap_bh, EXT4_INODES_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); + ext4_group_desc_csum_set(sb, group, gdp); ext4_unlock_group(sb, group); } @@ -1181,7 +1178,7 @@ int ext4_init_inode_table(struct super_block *sb, ext4_group_t group, skip_zeroout: ext4_lock_group(sb, group); gdp->bg_flags |= cpu_to_le16(EXT4_BG_INODE_ZEROED); - gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); + ext4_group_desc_csum_set(sb, group, gdp); ext4_unlock_group(sb, group); BUFFER_TRACE(group_desc_bh, diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 16a67359b4c7..7bccdf32a32c 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3584,8 +3584,7 @@ make_io: b = table; end = b + EXT4_SB(sb)->s_inode_readahead_blks; num = EXT4_INODES_PER_GROUP(sb); - if (EXT4_HAS_RO_COMPAT_FEATURE(sb, - EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) + if (ext4_has_group_desc_csum(sb)) num -= ext4_itable_unused_count(sb, gdp); table += num / inodes_per_block; if (end > table) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 95a388fef397..ccb9c2f527d5 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -2799,7 +2799,7 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac, ext4_free_group_clusters_set(sb, gdp, len); ext4_block_bitmap_csum_set(sb, ac->ac_b_ex.fe_group, gdp, bitmap_bh, EXT4_BLOCKS_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, ac->ac_b_ex.fe_group, gdp); + ext4_group_desc_csum_set(sb, ac->ac_b_ex.fe_group, gdp); ext4_unlock_group(sb, ac->ac_b_ex.fe_group); percpu_counter_sub(&sbi->s_freeclusters_counter, ac->ac_b_ex.fe_len); @@ -4663,7 +4663,7 @@ do_more: ext4_free_group_clusters_set(sb, gdp, ret); ext4_block_bitmap_csum_set(sb, block_group, gdp, bitmap_bh, EXT4_BLOCKS_PER_GROUP(sb) / 8); - gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); + ext4_group_desc_csum_set(sb, block_group, gdp); ext4_unlock_group(sb, block_group); percpu_counter_add(&sbi->s_freeclusters_counter, count_clusters); @@ -4809,7 +4809,7 @@ int ext4_group_add_blocks(handle_t *handle, struct super_block *sb, ext4_free_group_clusters_set(sb, desc, blk_free_count); ext4_block_bitmap_csum_set(sb, block_group, desc, bitmap_bh, EXT4_BLOCKS_PER_GROUP(sb) / 8); - desc->bg_checksum = ext4_group_desc_csum(sbi, block_group, desc); + ext4_group_desc_csum_set(sb, block_group, desc); ext4_unlock_group(sb, block_group); percpu_counter_add(&sbi->s_freeclusters_counter, EXT4_B2C(sbi, blocks_freed)); diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index dc597e066308..a58ce7c507ae 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1160,7 +1160,7 @@ static int ext4_setup_new_descs(handle_t *handle, struct super_block *sb, EXT4_B2C(sbi, group_data->free_blocks_count)); ext4_free_inodes_set(sb, gdp, EXT4_INODES_PER_GROUP(sb)); gdp->bg_flags = cpu_to_le16(*bg_flags); - gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); + ext4_group_desc_csum_set(sb, group, gdp); err = ext4_handle_dirty_metadata(handle, NULL, gdb_bh); if (unlikely(err)) { @@ -1399,17 +1399,14 @@ static int ext4_setup_next_flex_gd(struct super_block *sb, (1 + ext4_bg_num_gdb(sb, group + i) + le16_to_cpu(es->s_reserved_gdt_blocks)) : 0; group_data[i].free_blocks_count = blocks_per_group - overhead; - if (EXT4_HAS_RO_COMPAT_FEATURE(sb, - EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) + if (ext4_has_group_desc_csum(sb)) flex_gd->bg_flags[i] = EXT4_BG_BLOCK_UNINIT | EXT4_BG_INODE_UNINIT; else flex_gd->bg_flags[i] = EXT4_BG_INODE_ZEROED; } - if (last_group == n_group && - EXT4_HAS_RO_COMPAT_FEATURE(sb, - EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) + if (last_group == n_group && ext4_has_group_desc_csum(sb)) /* We need to initialize block bitmap of last group. */ flex_gd->bg_flags[i - 1] &= ~EXT4_BG_BLOCK_UNINIT; 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 967ac8af4475ce45474800709b12137aa7634c77 Mon Sep 17 00:00:00 2001 From: Haogang Chen Date: Mon, 28 May 2012 14:21:55 -0400 Subject: ext4: fix potential integer overflow in alloc_flex_gd() In alloc_flex_gd(), when flexbg_size is large, kmalloc size would overflow and flex_gd->groups would point to a buffer smaller than expected, causing OOB accesses when it is used. Note that in ext4_resize_fs(), flexbg_size is calculated using sbi->s_log_groups_per_flex, which is read from the disk and only bounded to [1, 31]. The patch returns NULL for too large flexbg_size. Reviewed-by: Eric Sandeen Signed-off-by: Haogang Chen Signed-off-by: "Theodore Ts'o" Cc: stable@kernel.org --- fs/ext4/resize.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/ext4/resize.c') diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index a58ce7c507ae..05c7979226e5 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -161,6 +161,8 @@ static struct ext4_new_flex_group_data *alloc_flex_gd(unsigned long flexbg_size) if (flex_gd == NULL) goto out3; + if (flexbg_size >= UINT_MAX / sizeof(struct ext4_new_flex_group_data)) + goto out2; flex_gd->count = flexbg_size; flex_gd->groups = kmalloc(sizeof(struct ext4_new_group_data) * -- 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/resize.c | 2 +- fs/ext4/super.c | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'fs/ext4/resize.c') diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index 05c7979226e5..7ea6cbb44121 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1145,7 +1145,7 @@ static int ext4_setup_new_descs(handle_t *handle, struct super_block *sb, */ gdb_bh = sbi->s_group_desc[gdb_num]; /* Update group descriptor block for new group */ - gdp = (struct ext4_group_desc *)((char *)gdb_bh->b_data + + gdp = (struct ext4_group_desc *)(gdb_bh->b_data + gdb_off * EXT4_DESC_SIZE(sb)); memset(gdp, 0, EXT4_DESC_SIZE(sb)); 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