linux-cve-announce - CVE-2025-38580: ext4: fix inode use after free in ext4_end_io_rsv

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <2025081913-CVE-2025-38580-554b@gregkh>
Date: Tue, 19 Aug 2025 19:18:26 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2025-38580: ext4: fix inode use after free in ext4_end_io_rsv_work()

From: Greg Kroah-Hartman <gregkh@...nel.org>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

ext4: fix inode use after free in ext4_end_io_rsv_work()

In ext4_io_end_defer_completion(), check if io_end->list_vec is empty to
avoid adding an io_end that requires no conversion to the
i_rsv_conversion_list, which in turn prevents starting an unnecessary
worker. An ext4_emergency_state() check is also added to avoid attempting
to abort the journal in an emergency state.

Additionally, ext4_put_io_end_defer() is refactored to call
ext4_io_end_defer_completion() directly instead of being open-coded.
This also prevents starting an unnecessary worker when EXT4_IO_END_FAILED
is set but data_err=abort is not enabled.

This ensures that the check in ext4_put_io_end_defer() is consistent with
the check in ext4_end_bio(). Otherwise, we might add an io_end to the
i_rsv_conversion_list and then call ext4_finish_bio(), after which the
inode could be freed before ext4_end_io_rsv_work() is called, triggering
a use-after-free issue.

The Linux kernel CVE team has assigned CVE-2025-38580 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 6.15 with commit ce51afb8cc5e1867ea0dfdf5e92ddbe31a1fad5d and fixed in 6.15.10 with commit ac999862b98a0f49e858e509f776be51406f1e77
	Issue introduced in 6.15 with commit ce51afb8cc5e1867ea0dfdf5e92ddbe31a1fad5d and fixed in 6.16.1 with commit 469c44e66e2110054949609dde095788320139d0
	Issue introduced in 6.15 with commit ce51afb8cc5e1867ea0dfdf5e92ddbe31a1fad5d and fixed in 6.17-rc1 with commit c678bdc998754589cea2e6afab9401d7d8312ac4

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2025-38580
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	fs/ext4/page-io.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/ac999862b98a0f49e858e509f776be51406f1e77
	https://git.kernel.org/stable/c/469c44e66e2110054949609dde095788320139d0
	https://git.kernel.org/stable/c/c678bdc998754589cea2e6afab9401d7d8312ac4