Bug 2461522 (CVE-2026-31548)

Summary: CVE-2026-31548 kernel: wifi: cfg80211: cancel pmsr_free_wk in cfg80211_pmsr_wdev_down
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's `cfg80211` Wi-Fi subsystem. When a Wi-Fi interface is shut down, a scheduled work item (`pmsr_free_wk`) may not be properly cancelled. This can lead to the work item attempting to operate on an already removed interface, resulting in undefined behavior and potential system crashes, causing a Denial of Service (DoS).
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Description OSIDB Bzimport 2026-04-24 15:06:24 UTC 
In the Linux kernel, the following vulnerability has been resolved:

wifi: cfg80211: cancel pmsr_free_wk in cfg80211_pmsr_wdev_down

When the nl80211 socket that originated a PMSR request is
closed, cfg80211_release_pmsr() sets the request's nl_portid
to zero and schedules pmsr_free_wk to process the abort
asynchronously. If the interface is concurrently torn down
before that work runs, cfg80211_pmsr_wdev_down() calls
cfg80211_pmsr_process_abort() directly. However, the already-
scheduled pmsr_free_wk work item remains pending and may run
after the interface has been removed from the driver. This
could cause the driver's abort_pmsr callback to operate on a
torn-down interface, leading to undefined behavior and
potential crashes.

Cancel pmsr_free_wk synchronously in cfg80211_pmsr_wdev_down()
before calling cfg80211_pmsr_process_abort(). This ensures any
pending or in-progress work is drained before interface teardown
proceeds, preventing the work from invoking the driver abort
callback after the interface is gone.
Comment 1 Keith Grant 2026-04-24 17:03:01 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026042425-CVE-2026-31548-3d88@gregkh/T