CVE-2025-38643

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

wifi: cfg80211: Add missing lock in cfg80211_check_and_end_cac()

Callers of wdev_chandef() must hold the wiphy mutex.

But the worker cfg80211_propagate_cac_done_wk() never takes the lock.

Which triggers the warning below with the mesh_peer_connected_dfs

test from hostapd and not (yet) released mac80211 code changes:

WARNING: CPU: 0 PID: 495 at net/wireless/chan.c:1552 wdev_chandef+0x60/0x165

Modules linked in:

CPU: 0 UID: 0 PID: 495 Comm: kworker/u4:2 Not tainted 6.14.0-rc5-wt-g03960e6f9d47 #33 13c287eeabfe1efea01c0bcc863723ab082e17cf

Workqueue: cfg80211 cfg80211_propagate_cac_done_wk

Stack:

00000000 00000001 ffffff00 6093267c

00000000 6002ec30 6d577c50 60037608

00000000 67e8d108 6063717b 00000000

Call Trace:

[<6002ec30>] ? _printk+0x0/0x98

[<6003c2b3>] show_stack+0x10e/0x11a

[<6002ec30>] ? _printk+0x0/0x98

[<60037608>] dump_stack_lvl+0x71/0xb8

[<6063717b>] ? wdev_chandef+0x60/0x165

[<6003766d>] dump_stack+0x1e/0x20

[<6005d1b7>] __warn+0x101/0x20f

[<6005d3a8>] warn_slowpath_fmt+0xe3/0x15d

[<600b0c5c>] ? mark_lock.part.0+0x0/0x4ec

[<60751191>] ? __this_cpu_preempt_check+0x0/0x16

[<600b11a2>] ? mark_held_locks+0x5a/0x6e

[<6005d2c5>] ? warn_slowpath_fmt+0x0/0x15d

[<60052e53>] ? unblock_signals+0x3a/0xe7

[<60052f2d>] ? um_set_signals+0x2d/0x43

[<60751191>] ? __this_cpu_preempt_check+0x0/0x16

[<607508b2>] ? lock_is_held_type+0x207/0x21f

[<6063717b>] wdev_chandef+0x60/0x165

[<605f89b4>] regulatory_propagate_dfs_state+0x247/0x43f

[<60052f00>] ? um_set_signals+0x0/0x43

[<605e6bfd>] cfg80211_propagate_cac_done_wk+0x3a/0x4a

[<6007e460>] process_scheduled_works+0x3bc/0x60e

[<6007d0ec>] ? move_linked_works+0x4d/0x81

[<6007d120>] ? assign_work+0x0/0xaa

[<6007f81f>] worker_thread+0x220/0x2dc

[<600786ef>] ? set_pf_worker+0x0/0x57

[<60087c96>] ? to_kthread+0x0/0x43

[<6008ab3c>] kthread+0x2d3/0x2e2

[<6007f5ff>] ? worker_thread+0x0/0x2dc

[<6006c05b>] ? calculate_sigpending+0x0/0x56

[<6003b37d>] new_thread_handler+0x4a/0x64

irq event stamp: 614611

hardirqs last enabled at (614621): [<00000000600bc96b>] __up_console_sem+0x82/0xaf

hardirqs last disabled at (614630): [<00000000600bc92c>] __up_console_sem+0x43/0xaf

softirqs last enabled at (614268): [<00000000606c55c6>] __ieee80211_wake_queue+0x933/0x985

softirqs last disabled at (614266): [<00000000606c52d6>] __ieee80211_wake_queue+0x643/0x985