CVE-2026-80990: net: thunderbolt: Release the Rx HopID that was handed out on mismatch

CVE-2026-80990: net: thunderbolt: Release the Rx HopID that was handed out on mismatch

[Greg Kroah-Hartman]

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

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

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

net: thunderbolt: Release the Rx HopID that was handed out on mismatch

tb_xdomain_alloc_in_hopid() passes the wanted HopID to ida_alloc_range()
as the lower bound, so a taken id is not an error there: the allocator
returns the next free one above it. tbnet_connected_work() asks for the
peer's transmit path, treats any other id as a failure and returns
without releasing what it got, so that allocation stays live for the rest
of the XDomain connection with nothing left holding a reference to it.

Release the id when it is not the one we asked for, the same way the
error unwind at the end of the function releases the expected one.

The Linux kernel CVE team has assigned CVE-2026-80990 to this issue.


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

	Issue introduced in 5.13 with commit 180b0689425c6fb2b35e69a3316ee38371a782df and fixed in 6.12.109 with commit 9eac1817bfc5fa76e3a2d1b8fd824cc6ef5a9ab0
	Issue introduced in 5.13 with commit 180b0689425c6fb2b35e69a3316ee38371a782df and fixed in 6.18.50 with commit 61ff3c353e5d2ff4eb9d0b6d8d9e47805b136eea
	Issue introduced in 5.13 with commit 180b0689425c6fb2b35e69a3316ee38371a782df and fixed in 7.2.4 with commit 1c361f6cf39be7cc0ce37c0b67bd1cdf74b0a0c1
	Issue introduced in 5.13 with commit 180b0689425c6fb2b35e69a3316ee38371a782df and fixed in 7.3-rc1 with commit 2f1463554d0561a2fead81e3888604e5c1125e29

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-2026-80990
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/net/thunderbolt/main.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/9eac1817bfc5fa76e3a2d1b8fd824cc6ef5a9ab0
	https://git.kernel.org/stable/c/61ff3c353e5d2ff4eb9d0b6d8d9e47805b136eea
	https://git.kernel.org/stable/c/1c361f6cf39be7cc0ce37c0b67bd1cdf74b0a0c1
	https://git.kernel.org/stable/c/2f1463554d0561a2fead81e3888604e5c1125e29