CVE-2026-64586

Technical Description

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

wifi: brcmfmac: drain bus_reset work on device removal

brcmf_fw_crashed() and the debugfs "reset" entry both schedule

drvr->bus_reset, whose callback recovers drvr through container_of()

and dereferences it. The removal path frees drvr (brcmf_free ->

wiphy_free) without draining the work, so a bus_reset callback pending

or running during removal can outlive drvr.

Cancellation cannot live in brcmf_detach() or brcmf_free(): the work

callback reaches teardown through the bus .reset op (PCIe

brcmf_pcie_reset -> brcmf_detach; SDIO brcmf_sdio_bus_reset ->

brcmf_sdiod_remove -> brcmf_free), so cancelling there would wait for

the running work and deadlock.

Add a per-bus mutex (bus_reset_lock) and route all arming through

brcmf_bus_schedule_reset(), which under the lock skips when the bus is

marked removing. Each bus remove entry calls

brcmf_bus_cancel_reset_work(), which under the same lock sets removing

and cancels the

Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

References