CVE-2026-80898: netfs: clear PG_private_2 on copy-to-cache append failure

CVE-2026-80898: netfs: clear PG_private_2 on copy-to-cache append failure

[Greg Kroah-Hartman]

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

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

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

netfs: clear PG_private_2 on copy-to-cache append failure

netfs_pgpriv2_copy_to_cache() marks the folio with PG_private_2 before
netfs_pgpriv2_copy_folio() appends it to the copy-to-cache rolling
buffer.

If the append fails, the folio is not queued for cache writeback, so
the PG_private_2 state and its reference must be released immediately.

The Linux kernel CVE team has assigned CVE-2026-80898 to this issue.


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

	Issue introduced in 6.14 with commit e2d46f2ec332533816417b60933954173f602121 and fixed in 6.18.44 with commit 627826ef4208042b0470d1a3fdb729ce35471a0d
	Issue introduced in 6.14 with commit e2d46f2ec332533816417b60933954173f602121 and fixed in 7.1.8 with commit 614b7f4bfcf665a751ae89ff9ae336a1b2d5af4e
	Issue introduced in 6.14 with commit e2d46f2ec332533816417b60933954173f602121 and fixed in 7.2 with commit a81fc9266e1c5fef9ccf675a9b44b2f4ab464923

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-2026-80898
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/netfs/read_pgpriv2.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/627826ef4208042b0470d1a3fdb729ce35471a0d
	https://git.kernel.org/stable/c/614b7f4bfcf665a751ae89ff9ae336a1b2d5af4e
	https://git.kernel.org/stable/c/a81fc9266e1c5fef9ccf675a9b44b2f4ab464923