Subject: CVE-2024-41071: wifi: mac80211: Avoid address calculations via out of bounds array indexing

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

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

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

wifi: mac80211: Avoid address calculations via out of bounds array indexing

req->n_channels must be set before req->channels[] can be used.

This patch fixes one of the issues encountered in [1].

[   83.964255] UBSAN: array-index-out-of-bounds in net/mac80211/scan.c:364:4
[   83.964258] index 0 is out of range for type 'struct ieee80211_channel *[]'
[...]
[   83.964264] Call Trace:
[   83.964267]  <TASK>
[   83.964269]  dump_stack_lvl+0x3f/0xc0
[   83.964274]  __ubsan_handle_out_of_bounds+0xec/0x110
[   83.964278]  ieee80211_prep_hw_scan+0x2db/0x4b0
[   83.964281]  __ieee80211_start_scan+0x601/0x990
[   83.964291]  nl80211_trigger_scan+0x874/0x980
[   83.964295]  genl_family_rcv_msg_doit+0xe8/0x160
[   83.964298]  genl_rcv_msg+0x240/0x270
[...]

[1] https://bugzilla.kernel.org/show_bug.cgi?id=218810

The Linux kernel CVE team has assigned CVE-2024-41071 to this issue.

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

	Fixed in 6.1.113 with commit a2bb0c5d0086
	Fixed in 6.6.57 with commit 26b177ecdd31
	Fixed in 6.9.11 with commit 4f43a614b1b8
	Fixed in 6.10 with commit 2663d0462eb3

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-2024-41071
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/scan.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/a2bb0c5d0086be5ab5054465dfaa381a1144905c
	https://git.kernel.org/stable/c/26b177ecdd311f20de4c379f0630858a675dfc0c
	https://git.kernel.org/stable/c/4f43a614b1b84f0d1e3c48cc541c3bfdf414a6d0
	https://git.kernel.org/stable/c/2663d0462eb32ae7c9b035300ab6b1523886c718