CVE-2026-64559: s390/pkey: Check length in PKEY_VERIFYPROTK ioctl

Greg Kroah-Hartman <[email protected]> Wed, 29 Jul 2026 18:31:14 +0200
Newsgroups org.kernel.vger.linux-cve-announce
Message-ID <2026072914-CVE-2026-64559-839b@gregkh>
From: Greg Kroah-Hartman <[email protected]>

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

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

s390/pkey: Check length in PKEY_VERIFYPROTK ioctl

Explicitly check the buffer length request structure provided by
user-space and fail, if it exceeds the buffer size.

The Linux kernel CVE team has assigned CVE-2026-64559 to this issue.


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

	Issue introduced in 6.12 with commit 8fcc231ce3bea12b78bb94b280cdc03cff342435 and fixed in 6.12.97 with commit 0a9e34ccbe772b8f321388cdbdf4f22b94e513e7
	Issue introduced in 6.12 with commit 8fcc231ce3bea12b78bb94b280cdc03cff342435 and fixed in 6.18.40 with commit 693bf91d4db134f9b1c2840c8e287eee3d993bac
	Issue introduced in 6.12 with commit 8fcc231ce3bea12b78bb94b280cdc03cff342435 and fixed in 7.1.5 with commit 7e7e03848c918aa0acad5ffd75d929e3afec1554
	Issue introduced in 6.12 with commit 8fcc231ce3bea12b78bb94b280cdc03cff342435 and fixed in 7.2-rc1 with commit b3d4ab2d7df9426f7f1d3671d7e2108f2ca6e970

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-2026-64559
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:
	drivers/s390/crypto/pkey_api.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/0a9e34ccbe772b8f321388cdbdf4f22b94e513e7
	https://git.kernel.org/stable/c/693bf91d4db134f9b1c2840c8e287eee3d993bac
	https://git.kernel.org/stable/c/7e7e03848c918aa0acad5ffd75d929e3afec1554
	https://git.kernel.org/stable/c/b3d4ab2d7df9426f7f1d3671d7e2108f2ca6e970