CVE-2026-93072: irqchip/renesas-irqc: Fix generic interrupt chip leak on remove

CVE-2026-93072: irqchip/renesas-irqc: Fix generic interrupt chip leak on remove

[Greg Kroah-Hartman]

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

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

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

irqchip/renesas-irqc: Fix generic interrupt chip leak on remove

The driver allocates domain generic chips probe. However, on driver
removal, the generic chips are not automatically freed when the interrupt
domain is removed because the domain flags do not include
IRQ_DOMAIN_FLAG_DESTROY_GC.

This causes both the domain generic chips structure and the associated
generic chips to be leaked. Additionally, the generic chips remain on the
global list and may later be accessed by generic interrupt chip suspend,
resume, or shutdown callbacks after the driver has been removed,
potentially resulting in a use-after-free and kernel crash.

Fix the resource leak by setting IRQ_DOMAIN_FLAG_DESTROY_GC on the
interrupt domain; this lets the interrupt domain core automatically
release all generic chips when irq_domain_remove() is invoked, removing
the need for manual cleanup calls in error paths and remove callback.

The Linux kernel CVE team has assigned CVE-2026-93072 to this issue.


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

	Issue introduced in 4.4 with commit 99c221df33fbfa1b30e15dee879eb0a9ae1be353 and fixed in 6.6.157 with commit 3d39757ef791f90028da9c8b7c1fbbb497237e58
	Issue introduced in 4.4 with commit 99c221df33fbfa1b30e15dee879eb0a9ae1be353 and fixed in 6.12.110 with commit 4bf7614d048434326081eef0ebef33cb77fe2ffc
	Issue introduced in 4.4 with commit 99c221df33fbfa1b30e15dee879eb0a9ae1be353 and fixed in 6.18.52 with commit 9acc996cb2e8477ae81bd7c067fec15202d6bc89
	Issue introduced in 4.4 with commit 99c221df33fbfa1b30e15dee879eb0a9ae1be353 and fixed in 7.2.6 with commit 7c614f83301d464e2fb498d63552490d137ea10d
	Issue introduced in 4.4 with commit 99c221df33fbfa1b30e15dee879eb0a9ae1be353 and fixed in 7.3-rc1 with commit 616dd89d81ad9a3cf1cfff4088a4c43e4e00d6ba

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-2026-93072
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/irqchip/irq-renesas-irqc.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/3d39757ef791f90028da9c8b7c1fbbb497237e58
	https://git.kernel.org/stable/c/4bf7614d048434326081eef0ebef33cb77fe2ffc
	https://git.kernel.org/stable/c/9acc996cb2e8477ae81bd7c067fec15202d6bc89
	https://git.kernel.org/stable/c/7c614f83301d464e2fb498d63552490d137ea10d
	https://git.kernel.org/stable/c/616dd89d81ad9a3cf1cfff4088a4c43e4e00d6ba