3.16.85-rc1 review patch. If anyone has any objections, please let me know.
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From: Theodore Ts'o tytso@mit.edu
commit 345c0dbf3a30872d9b204db96b5857cd00808cae upstream.
Add the blocks which belong to the journal inode to block_validity's system zone so attempts to deallocate or overwrite the journal due a corrupted file system where the journal blocks are also claimed by another inode.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202879 Signed-off-by: Theodore Ts'o tytso@mit.edu Cc: stable@kernel.org [bwh: Backported to 3.16: - Use EXT4_HAS_COMPAT_FEATURE() - Use EIO instead of EFSCORRUPTED] Signed-off-by: Ben Hutchings ben@decadent.org.uk --- --- a/fs/ext4/block_validity.c +++ b/fs/ext4/block_validity.c @@ -137,6 +137,48 @@ static void debug_print_tree(struct ext4 printk("\n"); }
+static int ext4_protect_reserved_inode(struct super_block *sb, u32 ino) +{ + struct inode *inode; + struct ext4_sb_info *sbi = EXT4_SB(sb); + struct ext4_map_blocks map; + u32 i = 0, err = 0, num, n; + + if ((ino < EXT4_ROOT_INO) || + (ino > le32_to_cpu(sbi->s_es->s_inodes_count))) + return -EINVAL; + inode = ext4_iget(sb, ino, EXT4_IGET_SPECIAL); + if (IS_ERR(inode)) + return PTR_ERR(inode); + num = (inode->i_size + sb->s_blocksize - 1) >> sb->s_blocksize_bits; + while (i < num) { + map.m_lblk = i; + map.m_len = num - i; + n = ext4_map_blocks(NULL, inode, &map, 0); + if (n < 0) { + err = n; + break; + } + if (n == 0) { + i++; + } else { + if (!ext4_data_block_valid(sbi, map.m_pblk, n)) { + ext4_error(sb, "blocks %llu-%llu from inode %u " + "overlap system zone", map.m_pblk, + map.m_pblk + map.m_len - 1, ino); + err = -EIO; + break; + } + err = add_system_zone(sbi, map.m_pblk, n); + if (err < 0) + break; + i += n; + } + } + iput(inode); + return err; +} + int ext4_setup_system_zone(struct super_block *sb) { ext4_group_t ngroups = ext4_get_groups_count(sb); @@ -171,6 +213,13 @@ int ext4_setup_system_zone(struct super_ if (ret) return ret; } + if (EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL) && + sbi->s_es->s_journal_inum) { + ret = ext4_protect_reserved_inode(sb, + le32_to_cpu(sbi->s_es->s_journal_inum)); + if (ret) + return ret; + }
if (test_opt(sb, DEBUG)) debug_print_tree(EXT4_SB(sb)); --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -411,6 +411,11 @@ static int __check_block_validity(struct unsigned int line, struct ext4_map_blocks *map) { + if (EXT4_HAS_COMPAT_FEATURE(inode->i_sb, + EXT4_FEATURE_COMPAT_HAS_JOURNAL) && + (inode->i_ino == + le32_to_cpu(EXT4_SB(inode->i_sb)->s_es->s_journal_inum))) + return 0; if (!ext4_data_block_valid(EXT4_SB(inode->i_sb), map->m_pblk, map->m_len)) { ext4_error_inode(inode, func, line, map->m_pblk,