CVE-2026-64212: wifi: iwlwifi: mld: don't dereference a pointer before NULL checking it

From: Greg Kroah-Hartman <[email protected]>

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

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

wifi: iwlwifi: mld: don't dereference a pointer before NULL checking it

In iwl_mld_remove_link, the link->fw_id is saved at the beginning of the
function so we have it after we freed the link.

But the link pointer can be NULL, and is not checked when the fw_id is
stored.

Fix it by simply freeing the link at the end of the function.

fFixes: 0e66a39f4f0e ("wifi: iwlwifi: fix potential use after free in iwl_mld_remove_link()")

The Linux kernel CVE team has assigned CVE-2026-64212 to this issue.


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

	Fixed in 6.18.34 with commit 3a74aaad047353da3344aed32e9042d4f334f926
	Fixed in 7.0.11 with commit b6b4db85c7baf0788c5e7ec61350c1ff2bb775e0
	Fixed in 7.1 with commit d733ed481fd20a8e7bfe5119c4e77761ba3f87ee

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-2026-64212
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/wireless/intel/iwlwifi/mld/link.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/3a74aaad047353da3344aed32e9042d4f334f926
	https://git.kernel.org/stable/c/b6b4db85c7baf0788c5e7ec61350c1ff2bb775e0
	https://git.kernel.org/stable/c/d733ed481fd20a8e7bfe5119c4e77761ba3f87ee