From: Eric Sandeen on gitlab.com https://gitlab.com/cki-project/kernel-ark/-/merge_requests/2916#note_1753622935 Sounds about right. So 7 years ago. V4 support **will** go away upstream. The upstream commit says more: ``` commit b96cb835 Author: Darrick J. Wong darrick.wong@xxxxxxxxxx Date: Thu Sep 10 10:57:17 2020 -0700 xfs: deprecate the V4 format The V4 filesystem format contains known weaknesses in the on-disk format that make metadata verification diffiult. In addition, the format does not support dates past 2038 and will not be upgraded to do so. We should start the process of retiring the old format to close off attack surfaces and to encourage users to migrate onto V5. Therefore, make XFS V4 support a configurable option. For the first period it will be default Y in case some distributors want to withdraw support early; for the second period it will be default N so that anyone who wishes to continue support can do so; and after that, support will be removed from the kernel. Dates for these events have been added to the upstream kernel. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> Reviewed-by: Dave Chinner <dchinner@xxxxxxxxxx> Reviewed-by: Eric Sandeen <sandeen@xxxxxxxxxx> ``` and it adds this documentation: ``` +Deprecation of V4 Format +======================== + +The V4 filesystem format lacks certain features that are supported by +the V5 format, such as metadata checksumming, strengthened metadata +verification, and the ability to store timestamps past the year 2038. +Because of this, the V4 format is deprecated. All users should upgrade +by backing up their files, reformatting, and restoring from the backup. + +Administrators and users can detect a V4 filesystem by running xfs_info +against a filesystem mountpoint and checking for a string containing +"crc=". If no such string is found, please upgrade xfsprogs to the +latest version and try again. + +The deprecation will take place in two parts. Support for mounting V4 +filesystems can now be disabled at kernel build time via Kconfig option. +The option will default to yes until September 2025, at which time it +will be changed to default to no. In September 2030, support will be +removed from the codebase entirely. + +Note: Distributors may choose to withdraw V4 format support earlier than +the dates listed above. ``` Fedora could wait until upstream kills it, but we need to get out in front of this for RHEL due to its long lifetime. Disabling V4 also greatly reduces the fuzzing attack surface for XFS, which has in the past generated a lot of CVE activity. -- _______________________________________________ kernel mailing list -- kernel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to kernel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/kernel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue
