CVE-2026-68355: wifi: ath11k: fix potential buffer underflow in ath11k_hal_rx_msdu_list_get()

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

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

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

wifi: ath11k: fix potential buffer underflow in ath11k_hal_rx_msdu_list_get()

When the first entry in msdu_details has a zero buffer address,
the code accesses msdu_details[i - 1] with i == 0, causing a
buffer underflow.

Fix similarly to ath12k_wifi7_hal_rx_msdu_list_get() by adding
a separate check for i == 0 before the main condition to prevent
the out-of-bounds access.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

The Linux kernel CVE team has assigned CVE-2026-68355 to this issue.


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

	Issue introduced in 5.6 with commit d5c65159f2895379e11ca13f62feabe93278985d and fixed in 6.6.148 with commit 69a6a4f60b2da92c0bdfd9264b8ffe053f51f52a
	Issue introduced in 5.6 with commit d5c65159f2895379e11ca13f62feabe93278985d and fixed in 6.12.101 with commit 904367381a922aa2dc3e8bd2488e6c9180516c7a
	Issue introduced in 5.6 with commit d5c65159f2895379e11ca13f62feabe93278985d and fixed in 6.18.42 with commit a154ca3c441a67d36b3a9ea63a4f11b06abe6223
	Issue introduced in 5.6 with commit d5c65159f2895379e11ca13f62feabe93278985d and fixed in 7.1.6 with commit 725c1c3a8c5d920a7d3f5887412f2ad8e95a74f5
	Issue introduced in 5.6 with commit d5c65159f2895379e11ca13f62feabe93278985d and fixed in 7.2-rc5 with commit 7f11e70629650ff6ea140984e5ce188b775b2683

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-2026-68355
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/ath11k/dp_rx.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/69a6a4f60b2da92c0bdfd9264b8ffe053f51f52a
	https://git.kernel.org/stable/c/904367381a922aa2dc3e8bd2488e6c9180516c7a
	https://git.kernel.org/stable/c/a154ca3c441a67d36b3a9ea63a4f11b06abe6223
	https://git.kernel.org/stable/c/725c1c3a8c5d920a7d3f5887412f2ad8e95a74f5
	https://git.kernel.org/stable/c/7f11e70629650ff6ea140984e5ce188b775b2683