CVE-2026-89441: mmc: via-sdmmc: cancel card-detect work on remove

CVE-2026-89441: mmc: via-sdmmc: cancel card-detect work on remove

[Greg Kroah-Hartman]

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

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

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

mmc: via-sdmmc: cancel card-detect work on remove

Disabling the device interrupt and freeing the IRQ prevents new card-detect
work from being queued, but carddet_work already queued by the handler can
still run after via_sd_remove() returns. via_sdc_card_detect() recovers the
host through container_of() and dereferences its MMIO base; once remove()
returns the host can be freed, so that work would touch freed memory.

Cancel carddet_work after freeing the IRQ and before cancelling
finish_bh_work, which the card-detect handler can also queue. carddet_work
can re-enable the interrupt through via_reset_pcictrl(); mask it again
afterwards.

This issue was found by an in-house static analysis tool and confirmed by
manual code review.

The Linux kernel CVE team has assigned CVE-2026-89441 to this issue.


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

	Issue introduced in 2.6.31 with commit f0bf7f61b8405224bc52fc9a3ccd167a68126e00 and fixed in 6.18.50 with commit f7ff3027ef004a331ef911a4886f12bc2e996037
	Issue introduced in 2.6.31 with commit f0bf7f61b8405224bc52fc9a3ccd167a68126e00 and fixed in 7.2.4 with commit eaca730c6f5e3609df62a0469fb789235a93d276
	Issue introduced in 2.6.31 with commit f0bf7f61b8405224bc52fc9a3ccd167a68126e00 and fixed in 7.3-rc1 with commit 57e5d877f898d5e5c9d672a77bb6bdd24f0d9bf5

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-2026-89441
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/mmc/host/via-sdmmc.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/f7ff3027ef004a331ef911a4886f12bc2e996037
	https://git.kernel.org/stable/c/eaca730c6f5e3609df62a0469fb789235a93d276
	https://git.kernel.org/stable/c/57e5d877f898d5e5c9d672a77bb6bdd24f0d9bf5