CVE-2026-72004: wifi: mac80211: fix memory leak in ieee80211_register_hw()

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

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

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

wifi: mac80211: fix memory leak in ieee80211_register_hw()

If kmemdup() fails while copying supported band structures, the error
path jumps to fail_rate. This skips rate_control_deinitialize() and
leaks the initialized local->rate_ctrl.

Fix this by adding a fail_band label that shares the rate-control cleanup
path before falling through to the remaining teardown.

The bug was first flagged by an experimental analysis tool we are
developing for kernel memory-management bugs while analyzing
v6.13-rc1. The tool is still under development and is not yet publicly
available. Manual inspection confirms that the bug is still present in
v7.1-rc7.

An x86_64 allyesconfig build showed no new warnings. As we do not have a
suitable mac80211 device/driver combination to test with, no runtime
testing was able to be performed.

The Linux kernel CVE team has assigned CVE-2026-72004 to this issue.


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

	Issue introduced in 4.20 with commit 09b4a4faf9d037990ac4f8110dd944b27b42d5df and fixed in 5.10.261 with commit f01eec75fd372961550b928902f3a2c11fca1daf
	Issue introduced in 4.20 with commit 09b4a4faf9d037990ac4f8110dd944b27b42d5df and fixed in 5.15.212 with commit 3d8b9b290421c3cd505fcd2f551f143f8142786a
	Issue introduced in 4.20 with commit 09b4a4faf9d037990ac4f8110dd944b27b42d5df and fixed in 6.1.178 with commit 08b71bd92317f99642b842cfc0d30200868162fc
	Issue introduced in 4.20 with commit 09b4a4faf9d037990ac4f8110dd944b27b42d5df and fixed in 6.6.145 with commit a02b52fe54f7b5107aefa1ce28c2f69749c57616
	Issue introduced in 4.20 with commit 09b4a4faf9d037990ac4f8110dd944b27b42d5df and fixed in 6.12.97 with commit 45e9ac538cdff7bce656d731114a64eda85af0d7
	Issue introduced in 4.20 with commit 09b4a4faf9d037990ac4f8110dd944b27b42d5df and fixed in 6.18.40 with commit bdc0b8bfdc142439d6708b072e8159eb515ee7b0
	Issue introduced in 4.20 with commit 09b4a4faf9d037990ac4f8110dd944b27b42d5df and fixed in 7.1.5 with commit a7584f261e64fe14e45bdf70f343e16c1ee3a037
	Issue introduced in 4.20 with commit 09b4a4faf9d037990ac4f8110dd944b27b42d5df and fixed in 7.2-rc4 with commit 95fc02722edde02946d0d475221f2b2054d3d8ba

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-2026-72004
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:
	net/mac80211/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/f01eec75fd372961550b928902f3a2c11fca1daf
	https://git.kernel.org/stable/c/3d8b9b290421c3cd505fcd2f551f143f8142786a
	https://git.kernel.org/stable/c/08b71bd92317f99642b842cfc0d30200868162fc
	https://git.kernel.org/stable/c/a02b52fe54f7b5107aefa1ce28c2f69749c57616
	https://git.kernel.org/stable/c/45e9ac538cdff7bce656d731114a64eda85af0d7
	https://git.kernel.org/stable/c/bdc0b8bfdc142439d6708b072e8159eb515ee7b0
	https://git.kernel.org/stable/c/a7584f261e64fe14e45bdf70f343e16c1ee3a037
	https://git.kernel.org/stable/c/95fc02722edde02946d0d475221f2b2054d3d8ba