CVE-2026-68353: wifi: ath6kl: fix OOB read from firmware num_msg in TX complete handler

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

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

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

wifi: ath6kl: fix OOB read from firmware num_msg in TX complete handler

The firmware-controlled num_msg field (u8, 0-255) drives the loop in
ath6kl_wmi_tx_complete_event_rx() without validation against the buffer
length. This allows out-of-bounds reads of up to 1020 bytes past the
WMI event buffer when the firmware sends an inflated num_msg.

Add a check that the buffer is large enough to hold the fixed struct
and the num_msg variable-length entries.

The Linux kernel CVE team has assigned CVE-2026-68353 to this issue.


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

	Issue introduced in 3.2 with commit bdcd81707973cf8aa9305337166f8ee842a050d4 and fixed in 6.6.148 with commit 69ac7ba3a3df6654e7daa82674575a8c4a1a63ea
	Issue introduced in 3.2 with commit bdcd81707973cf8aa9305337166f8ee842a050d4 and fixed in 6.12.101 with commit 289edc3c71344b89e6522891147cfb8f61b088bb
	Issue introduced in 3.2 with commit bdcd81707973cf8aa9305337166f8ee842a050d4 and fixed in 6.18.42 with commit eb636fbc443149b3501c3f97e26225ddcb314a0f
	Issue introduced in 3.2 with commit bdcd81707973cf8aa9305337166f8ee842a050d4 and fixed in 7.1.6 with commit c38b0d5c661951b5dd082bdf31f8a57a0ce6e540
	Issue introduced in 3.2 with commit bdcd81707973cf8aa9305337166f8ee842a050d4 and fixed in 7.2-rc5 with commit 3a21c89215cc18f1a97c5e5bfd1da6d4f3d44495

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-2026-68353
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/ath/ath6kl/wmi.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/69ac7ba3a3df6654e7daa82674575a8c4a1a63ea
	https://git.kernel.org/stable/c/289edc3c71344b89e6522891147cfb8f61b088bb
	https://git.kernel.org/stable/c/eb636fbc443149b3501c3f97e26225ddcb314a0f
	https://git.kernel.org/stable/c/c38b0d5c661951b5dd082bdf31f8a57a0ce6e540
	https://git.kernel.org/stable/c/3a21c89215cc18f1a97c5e5bfd1da6d4f3d44495