kernel/linux.git/fs/ext4/block_validity.c, branch v6.6.132

ext4: make block validity check resistent to sb bh corruption

2025-05-02T05:51:00+00:00

[ Upstream commit ccad447a3d331a239477c281533bacb585b54a98 ] Block validity checks need to be skipped in case they are called for journal blocks since they are part of system's protected zone. Currently, this is done by checking inode->ino against sbi->s_es->s_journal_inum, which is a direct read from the ext4 sb buffer head. If someone modifies this underneath us then the s_journal_inum field might get corrupted. To prevent against this, change the check to directly compare the inode with journal->j_inode. **Slight change in behavior**: During journal init path, check_block_validity etc might be called for journal inode when sbi->s_journal is not set yet. In this case we now proceed with ext4_inode_block_valid() instead of returning early. Since systems zones have not been set yet, it is okay to proceed so we can perform basic checks on the blocks. Suggested-by: Baokun Li Reviewed-by: Baokun Li Reviewed-by: Jan Kara Reviewed-by: Zhang Yi Signed-off-by: Ojaswin Mujoo Link: https://patch.msgid.link/0c06bc9ebfcd6ccfed84a36e79147bf45ff5adc1.1743142920.git.ojaswin@linux.ibm.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

ext4: add correct group descriptors and reserved GDT blocks to system zone

2023-08-27T15:27:12+00:00

When setup_system_zone, flex_bg is not initialized so it is always 1. Use a new helper function, ext4_num_base_meta_blocks() which does not depend on sbi->s_log_groups_per_flex being initialized. [ Squashed two patches in the Link URL's below together into a single commit, which is simpler to review/understand. Also fix checkpatch warnings. --TYT ] Cc: stable@kernel.org Signed-off-by: Wang Jianjian Link: https://lore.kernel.org/r/tencent_21AF0D446A9916ED5C51492CC6C9A0A77B05@qq.com Link: https://lore.kernel.org/r/tencent_D744D1450CC169AEA77FCF0A64719909ED05@qq.com Signed-off-by: Theodore Ts'o

ext4: add ext4_sb_block_valid() refactored out of ext4_inode_block_valid()

2022-02-26T02:34:56+00:00

This API will be needed at places where we don't have an inode for e.g. while freeing blocks in ext4_group_add_blocks() Suggested-by: Jan Kara Signed-off-by: Ritesh Harjani Link: https://lore.kernel.org/r/dd34a236543ad5ae7123eeebe0cb69e6bdd44f34.1644992610.git.riteshh@linux.ibm.com Signed-off-by: Theodore Ts'o

ext4: standardize error message in ext4_protect_reserved_inode()

2020-12-17T18:30:55+00:00

We use __ext4_error() when ext4_protect_reserved_inode() finds filesystem corruption. However EXT4_ERROR_INODE_ERR() is perfectly capable of reporting all the needed information. So just use that. Signed-off-by: Jan Kara Reviewed-by: Andreas Dilger Link: https://lore.kernel.org/r/20201127113405.26867-4-jack@suse.cz Signed-off-by: Theodore Ts'o

ext4: update ext4_data_block_valid related comments

2020-12-09T19:11:27+00:00

Since ext4_data_block_valid() has been renamed to ext4_inode_block_valid(), the related comments need to be updated. Signed-off-by: Chunguang Xu Reviewed-by: Andreas Dilger Link: https://lore.kernel.org/r/1604764698-4269-5-git-send-email-brookxu@tencent.com Signed-off-by: Theodore Ts'o

ext4: rename system_blks to s_system_blks inside ext4_sb_info

2020-10-18T14:36:59+00:00

Rename system_blks to s_system_blks inside ext4_sb_info, keep the naming rules consistent with other variables, which is convenient for code reading and writing. Signed-off-by: Chunguang Xu Reviewed-by: Andreas Dilger Reviewed-by: Ritesh Harjani Link: https://lore.kernel.org/r/1600916623-544-2-git-send-email-brookxu@tencent.com Signed-off-by: Theodore Ts'o

ext4: correctly restore system zone info when remount fails

2020-08-07T18:12:37+00:00

When remounting filesystem fails late during remount handling and block_validity mount option is also changed during the remount, we fail to restore system zone information to a state matching the mount option. This is mostly harmless, just the block validity checking will not match the situation described by the mount option. Make sure these two are always consistent. Reported-by: Lukas Czerner Reviewed-by: Lukas Czerner Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20200728130437.7804-7-jack@suse.cz Signed-off-by: Theodore Ts'o

ext4: handle add_system_zone() failure in ext4_setup_system_zone()

2020-08-07T18:12:36+00:00

There's one place that fails to handle error from add_system_zone() call and thus we can fail to protect superblock and group-descriptor blocks properly in case of ENOMEM. Fix it. Reported-by: Lukas Czerner Reviewed-by: Lukas Czerner Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20200728130437.7804-6-jack@suse.cz Signed-off-by: Theodore Ts'o

ext4: fold ext4_data_block_valid_rcu() into the caller

2020-08-07T18:12:36+00:00

After the previous patch, ext4_data_block_valid_rcu() has a single caller. Fold it into it. Reviewed-by: Lukas Czerner Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20200728130437.7804-5-jack@suse.cz Signed-off-by: Theodore Ts'o

ext4: check journal inode extents more carefully

2020-08-07T18:12:36+00:00

Currently, system zones just track ranges of block, that are "important" fs metadata (bitmaps, group descriptors, journal blocks, etc.). This however complicates how extent tree (or indirect blocks) can be checked for inodes that actually track such metadata - currently the journal inode but arguably we should be treating quota files or resize inode similarly. We cannot run __ext4_ext_check() on such metadata inodes when loading their extents as that would immediately trigger the validity checks and so we just hack around that and special-case the journal inode. This however leads to a situation that a journal inode which has extent tree of depth at least one can have invalid extent tree that gets unnoticed until ext4_cache_extents() crashes. To overcome this limitation, track inode number each system zone belongs to (0 is used for zones not belonging to any inode). We can then verify inode number matches the expected one when verifying extent tree and thus avoid the false errors. With this there's no need to to special-case journal inode during extent tree checking anymore so remove it. Fixes: 0a944e8a6c66 ("ext4: don't perform block validity checks on the journal inode") Reported-by: Wolfgang Frisch Reviewed-by: Lukas Czerner Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20200728130437.7804-4-jack@suse.cz Signed-off-by: Theodore Ts'o