Zack's Kernel News
Zack's Kernel News

Chronicler Zack Brown reports on the latest news, views, dilemmas, and developments within the Linux kernel community.
Protecting Filesystems from Themselves
Chao Yu recently tried to revert a kernel commit for an F2FS patch. F2FS is a Samsung filesystem for solid state drives. Chao wanted to revert the patch because one of the kernel's generic tests expected F2FS to fail to mount a read-only partition. Ironically, as pointed out by Jaegeuk Kim, F2FS had no trouble mounting such a partition and giving the user full read access to all its data. So the filesystem failed the test … because it succeeded.
Jaegeuk suggested changing the test rather than reverting the patch, but Chao pointed out that the test was actually important for filesystems in general, not just F2FS. Changing the test for that one case, he said, would mean other filesystems might technically pass the test when they really should fail.
Chao also disagreed with Jaegeuk that F2FS handled the case properly. Walking through the code, he identified a certain point at which, he said, the device was then read-only, so that all writes would fail. Therefore, recovered data would not be able to persist beyond the expiration of the page cache. At that point, he said, the user would see stale data instead of the latest system state.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.

News
-
TuxCare Announces Support for AlmaLinux 9.2
Thanks to TuxCare, AlmaLinux 9.2 (and soon version 9.6) now enjoys years of ongoing patching and compliance.
-
Go-Based Botnet Attacking IoT Devices
Using an SSH credential brute-force attack, the Go-based PumaBot is exploiting IoT devices everywhere.
-
Plasma 6.5 Promises Better Memory Optimization
With the stable Plasma 6.4 on the horizon, KDE has a few new tricks up its sleeve for Plasma 6.5.
-
KaOS 2025.05 Officially Qt5 Free
If you're a fan of independent Linux distributions, the team behind KaOS is proud to announce the latest iteration that includes kernel 6.14 and KDE's Plasma 6.3.5.
-
Linux Kernel 6.15 Now Available
The latest Linux kernel is now available with several new features/improvements and the usual bug fixes.
-
Microsoft Makes Surprising WSL Announcement
In a move that might surprise some users, Microsoft has made Windows Subsystem for Linux open source.
-
Red Hat Releases RHEL 10 Early
Red Hat quietly rolled out the official release of RHEL 10.0 a bit early.
-
openSUSE Joins End of 10
openSUSE has decided to not only join the End of 10 movement but it also will no longer support the Deepin Desktop Environment.
-
New Version of Flatpak Released
Flatpak 1.16.1 is now available as the latest, stable version with various improvements.
-
IBM Announces Powerhouse Linux Server
IBM has unleashed a seriously powerful Linux server with the LinuxONE Emperor 5.