CVE-2026-23291: nfc: pn533: properly drop the usb interface reference on disconnect

CVE-2026-23291: nfc: pn533: properly drop the usb interface reference on disconnect

[Greg Kroah-Hartman]

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

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

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

nfc: pn533: properly drop the usb interface reference on disconnect

When the device is disconnected from the driver, there is a "dangling"
reference count on the usb interface that was grabbed in the probe
callback.  Fix this up by properly dropping the reference after we are
done with it.

The Linux kernel CVE team has assigned CVE-2026-23291 to this issue.


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

	Issue introduced in 3.1 with commit c46ee38620a2aa2b25b16bc9738ace80dbff76a4 and fixed in 6.1.167 with commit 7398d6570501edc55a50ece820f369ab3c1df2e7
	Issue introduced in 3.1 with commit c46ee38620a2aa2b25b16bc9738ace80dbff76a4 and fixed in 6.6.130 with commit d1f6d20b3c2642ec85ce6ea5da7155746c31c6d0
	Issue introduced in 3.1 with commit c46ee38620a2aa2b25b16bc9738ace80dbff76a4 and fixed in 6.12.77 with commit 7ff14eb070f0efecb2606f8d7aa01b77d188e886
	Issue introduced in 3.1 with commit c46ee38620a2aa2b25b16bc9738ace80dbff76a4 and fixed in 6.18.17 with commit 00477cab053dc4816b99141d8fcca7a479cfebeb
	Issue introduced in 3.1 with commit c46ee38620a2aa2b25b16bc9738ace80dbff76a4 and fixed in 6.19.7 with commit 4551d6cea00224ab65a0ef35e4e6da0e9c0a2d74
	Issue introduced in 3.1 with commit c46ee38620a2aa2b25b16bc9738ace80dbff76a4 and fixed in 7.0-rc2 with commit 12133a483dfa832241fbbf09321109a0ea8a520e

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-2026-23291
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/nfc/pn533/usb.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/7398d6570501edc55a50ece820f369ab3c1df2e7
	https://git.kernel.org/stable/c/d1f6d20b3c2642ec85ce6ea5da7155746c31c6d0
	https://git.kernel.org/stable/c/7ff14eb070f0efecb2606f8d7aa01b77d188e886
	https://git.kernel.org/stable/c/00477cab053dc4816b99141d8fcca7a479cfebeb
	https://git.kernel.org/stable/c/4551d6cea00224ab65a0ef35e4e6da0e9c0a2d74
	https://git.kernel.org/stable/c/12133a483dfa832241fbbf09321109a0ea8a520e