CVE-2026-46298: pseries/papr-hvpipe: Fix race with interrupt handler

CVE-2026-46298: pseries/papr-hvpipe: Fix race with interrupt handler

[Greg Kroah-Hartman]

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

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

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

pseries/papr-hvpipe: Fix race with interrupt handler

While executing ->ioctl handler or ->release handler, if an interrupt
fires on the same cpu, then we can enter into a deadlock.

This patch fixes both these handlers to take spin_lock_irq{save|restore}
versions of the lock to prevent this deadlock.

The Linux kernel CVE team has assigned CVE-2026-46298 to this issue.


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

	Issue introduced in 6.18 with commit 814ef095f12c9fa142043ee689500f3a41bb6dab and fixed in 7.0.7 with commit 342c966f81cfc3cb6c297e80b37a9f3a5d637d2c
	Issue introduced in 6.18 with commit 814ef095f12c9fa142043ee689500f3a41bb6dab and fixed in 7.1-rc3 with commit 7a4f0846ee6cc8cf44ae0046ed42e3259d1dd45b

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-2026-46298
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:
	arch/powerpc/platforms/pseries/papr-hvpipe.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/342c966f81cfc3cb6c297e80b37a9f3a5d637d2c
	https://git.kernel.org/stable/c/7a4f0846ee6cc8cf44ae0046ed42e3259d1dd45b