CVE-2026-68362: wifi: ath11k: fix NULL pointer dereference in ath11k_hal_srng_access_begin

CVE-2026-68362: wifi: ath11k: fix NULL pointer dereference in ath11k_hal_srng_access_begin

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

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

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

wifi: ath11k: fix NULL pointer dereference in ath11k_hal_srng_access_begin

In ATH11K_QMI_EVENT_FW_READY, ATH11K_FLAG_REGISTERED is set
unconditionally even when ath11k_core_qmi_firmware_ready() fails.
This leaves the driver in an inconsistent state where
initialization is considered complete although the firmware ready
handling did not finish successfully. During the subsequent SSR,
the driver enters the restart path based on this incorrect state
and dereferences uninitialized srng members, resulting in a NULL
pointer dereference.

Call trace:
  ath11k_hal_srng_access_begin+0xc/0x60 [ath11k] (P)
  ath11k_ce_cleanup_pipes+0x17c/0x180 [ath11k]
  ath11k_core_restart+0x40/0x168 [ath11k]

Fix this by:
- skipping firmware_ready if ATH11K_FLAG_REGISTERED is already set
- setting ATH11K_FLAG_REGISTERED only when firmware_ready succeeds
- setting ATH11K_FLAG_QMI_FAIL and aborting the FW_READY handling
on error

Tested-on: WCN6750 hw1.0 AHB WLAN.MSL.2.0.c2-00204-QCAMSLSWPLZ-1

The Linux kernel CVE team has assigned CVE-2026-68362 to this issue.


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

	Issue introduced in 6.1 with commit 6fe62a8cec51c756159c71be35a16b2cc8cbd4c0 and fixed in 6.6.148 with commit e517e207300edcf7f3a8f6c45f9155c0e419ffb9
	Issue introduced in 6.1 with commit 6fe62a8cec51c756159c71be35a16b2cc8cbd4c0 and fixed in 6.12.101 with commit d6bba659ac30d862ee7bab92862cd6e514f07521
	Issue introduced in 6.1 with commit 6fe62a8cec51c756159c71be35a16b2cc8cbd4c0 and fixed in 6.18.42 with commit e5394605f9a985cc3a8263e610ba84b33cbe7b0c
	Issue introduced in 6.1 with commit 6fe62a8cec51c756159c71be35a16b2cc8cbd4c0 and fixed in 7.1.6 with commit 4abb4e284d8897176e91d7a3168ee29ed876bb41
	Issue introduced in 6.1 with commit 6fe62a8cec51c756159c71be35a16b2cc8cbd4c0 and fixed in 7.2-rc5 with commit e8d85672dd7e2523f774caafba8f858384e18df7

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-2026-68362
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/qmi.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/e517e207300edcf7f3a8f6c45f9155c0e419ffb9
	https://git.kernel.org/stable/c/d6bba659ac30d862ee7bab92862cd6e514f07521
	https://git.kernel.org/stable/c/e5394605f9a985cc3a8263e610ba84b33cbe7b0c
	https://git.kernel.org/stable/c/4abb4e284d8897176e91d7a3168ee29ed876bb41
	https://git.kernel.org/stable/c/e8d85672dd7e2523f774caafba8f858384e18df7