CVE-2026-72384: irqchip/ts4800: Fix missing chained handler cleanup on remove

CVE-2026-72384: irqchip/ts4800: Fix missing chained handler cleanup on remove

[Greg Kroah-Hartman]

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

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

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

irqchip/ts4800: Fix missing chained handler cleanup on remove

The driver installs a chained handler for the parent interrupt during probe
using irq_set_chained_handler_and_data(), but the remove function does not
clear this handler. This leaves a dangling handler that may be called when
the parent interrupt fires after the driver has been removed, potentially
accessing freed memory and causing a kernel crash.

Additionally, the parent_irq obtained via irq_of_parse_and_map() is not
stored, making it inaccessible in the remove function. Moreover, interrupt
mappings created during probe are not properly disposed.

Fix this by:

   - Saving parent_irq in probe
   - Clearing the chained handler with NULL in ts4800_ic_remove()
   - Disposing all IRQ mappings before domain removal to prevent resource
     leaks

The Linux kernel CVE team has assigned CVE-2026-72384 to this issue.


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

	Issue introduced in 4.5 with commit d01f8633d52e4dac5ee598b87d49fd23346ccfd6 and fixed in 6.1.178 with commit b5b2b2cb6a91908e6c23958c9ce6d5ba2fdb686c
	Issue introduced in 4.5 with commit d01f8633d52e4dac5ee598b87d49fd23346ccfd6 and fixed in 6.6.145 with commit e6b674dc341c6add7d85bec2ec22caf1aad35795
	Issue introduced in 4.5 with commit d01f8633d52e4dac5ee598b87d49fd23346ccfd6 and fixed in 6.12.97 with commit 3f31f49afffa169cd01e6c37568c4df3eb1051af
	Issue introduced in 4.5 with commit d01f8633d52e4dac5ee598b87d49fd23346ccfd6 and fixed in 6.18.40 with commit 4e8d498d32b6c67d73bb8b317ff316ff37897a3e
	Issue introduced in 4.5 with commit d01f8633d52e4dac5ee598b87d49fd23346ccfd6 and fixed in 7.1.5 with commit 9ed0dca2aa05908b33ecf0bb15c7953947529542
	Issue introduced in 4.5 with commit d01f8633d52e4dac5ee598b87d49fd23346ccfd6 and fixed in 7.2-rc2 with commit 98bf7e54cec07d514b3575c11896a8b12d50ecc4

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-2026-72384
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-ts4800.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/b5b2b2cb6a91908e6c23958c9ce6d5ba2fdb686c
	https://git.kernel.org/stable/c/e6b674dc341c6add7d85bec2ec22caf1aad35795
	https://git.kernel.org/stable/c/3f31f49afffa169cd01e6c37568c4df3eb1051af
	https://git.kernel.org/stable/c/4e8d498d32b6c67d73bb8b317ff316ff37897a3e
	https://git.kernel.org/stable/c/9ed0dca2aa05908b33ecf0bb15c7953947529542
	https://git.kernel.org/stable/c/98bf7e54cec07d514b3575c11896a8b12d50ecc4