CVE-2026-74358

What the bug is

On 64-bit, ext4 dynamic inode states live in the upper half of i_flags, and ext4_test_inode_state() applies the corresponding +32 offset. The fast-commit wait and wake paths open-coded the wait key with the raw EXT4_STATE_* value. Add small helpers for the state wait word and bit, and use them for the FC_COMMITTING and FC_FLUSHING_DATA waits so the wait key follows the same mapping as the state helpers.

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

fs/ext4/ext4.h
fs/ext4/fast_commit.c

What this is

EXT4 FILE SYSTEMMAINTAINERS section matched on fs/ext4/ · linux-ext4@vger.kernel.org · Maintained

Kernel module

ext4

Check it on the machine

grep -w CONFIG_EXT4_FS /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

lsmod | grep -w ext4

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

Show whether Debian builds this, per release

Debian builds this code. Every release below compiles the affected file into the kernels it ships.

• bookworm, trixie, forky, sidb

b

built in on some flavours, a module on others

Build switch

CONFIG_EXT4_FS

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-08-15 (2 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.21%, higher than 10.0% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

unimportantsource

Subsystem

fs/ext4

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
6.16	6.18.40	e82d515092a0
6.16	7.1.5	d06df6e447a8
6.16	7.2	8b3bc93fee67