Go to file
Theodore Ts'o 9a8c5b0d06 ext4: update the backup superblock's at the end of the online resize
When expanding a file system using online resize, various fields in
the superblock (e.g., s_blocks_count, s_inodes_count, etc.) change.
To update the backup superblocks, the online resize uses the function
update_backups() in fs/ext4/resize.c.  This function was not updating
the checksum field in the backup superblocks.  This wasn't a big deal
previously, because e2fsck didn't care about the checksum field in the
backup superblock.  (And indeed, update_backups() goes all the way
back to the ext3 days, well before we had support for metadata
checksums.)

However, there is an alternate, more general way of updating
superblock fields, ext4_update_primary_sb() in fs/ext4/ioctl.c.  This
function does check the checksum of the backup superblock, and if it
doesn't match will mark the file system as corrupted.  That was
clearly not the intent, so avoid to aborting the resize when a bad
superblock is found.

In addition, teach update_backups() to properly update the checksum in
the backup superblocks.  We will eventually want to unify
updapte_backups() with the infrasture in ext4_update_primary_sb(), but
that's for another day.

Note: The problem has been around for a while; it just didn't really
matter until ext4_update_primary_sb() was added by commit bbc605cdb1
("ext4: implement support for get/set fs label").  And it became
trivially easy to reproduce after commit 827891a38a ("ext4: update
the s_overhead_clusters in the backup sb's when resizing") in v6.0.

Cc: stable@kernel.org # 5.17+
Fixes: bbc605cdb1 ("ext4: implement support for get/set fs label")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2022-10-27 23:21:40 -04:00
arch whack-a-mole: constifying struct path * 2022-10-06 17:31:02 -07:00
block STATX_DIOALIGN for 6.1 2022-10-03 20:33:41 -07:00
certs certs: make system keyring depend on built-in x509 parser 2022-09-24 04:31:18 +09:00
crypto crypto: blake2b: effectively disable frame size warning 2022-08-10 17:59:11 -07:00
Documentation The first two changes that involve files outside of fs/ext4: 2022-10-06 17:45:53 -07:00
drivers whack-a-mole: cropped up open-coded file_inode() uses... 2022-10-06 17:22:11 -07:00
fs ext4: update the backup superblock's at the end of the online resize 2022-10-27 23:21:40 -04:00
include The first two changes that involve files outside of fs/ext4: 2022-10-06 17:45:53 -07:00
init Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
io_uring whack-a-mole: constifying struct path * 2022-10-06 17:31:02 -07:00
ipc Updates to various subsystems which I help look after. lib, ocfs2, 2022-08-07 10:03:24 -07:00
kernel whack-a-mole: constifying struct path * 2022-10-06 17:31:02 -07:00
lib linux-kselftest-kunit-6.1-rc1 2022-10-06 12:57:55 -07:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm for-6.1-tag 2022-10-06 17:36:48 -07:00
net d_path pile 2022-10-06 16:55:41 -07:00
rust Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
samples ARM: driver updates for 6.1 2022-10-06 11:04:57 -07:00
scripts Networking changes for 6.1. 2022-10-04 13:38:03 -07:00
security whack-a-mole: constifying struct path * 2022-10-06 17:31:02 -07:00
sound sound updates for 6.1-rc1 2022-10-05 12:02:07 -07:00
tools linux-kselftest-kunit-6.1-rc1 2022-10-06 12:57:55 -07:00
usr Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
virt KVM: Drop unnecessary initialization of "ops" in kvm_ioctl_create_device() 2022-08-19 04:05:43 -04:00
.clang-format PCI/DOE: Add DOE mailbox support functions 2022-07-19 15:38:04 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
.mailmap Qualcomm ARM64 DTS fixes for 6.0 2022-09-23 16:44:37 +02:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS drm for 5.20/6.0 2022-08-03 19:52:08 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS linux-kselftest-next-6.1-rc1 2022-10-06 12:53:15 -07:00
Makefile hardening updates for v6.1-rc1 2022-10-03 17:24:22 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.