Bug 2555010 (CVE-2026-98632)

Summary: CVE-2026-98632 kernel: Bluetooth: mgmt: Dequeue pending mesh_send_sync entries on cancel
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: akhatavk, aos-team-art-private, asdas, dpaolell, jdelft, jupierce, lgarciaa, mbiarnes, ppalepu, ppostler, prdhamdh, rhel-process-autobot, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's Bluetooth subsystem. A local attacker can trigger a use-after-free condition by cancelling a pending Bluetooth mesh transmission while it remains queued for processing. When the system later attempts to handle the queued transmission using the already freed object, memory corruption occurs, which can lead to a Denial of Service (DoS) through a system crash or potential privilege escalation.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Description OSIDB Bzimport 2026-10-18 15:39:02 UTC 
In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: mgmt: Dequeue pending mesh_send_sync entries on cancel

In send_cancel(), pending mesh_tx objects are removed from the
hdev->mesh_pending list and freed via mesh_send_complete().  However, if
a mesh transmission was already queued onto hdev->cmd_sync_work_list via
mesh_next(), the queued entry retains a raw pointer to mesh_tx.

When hci_cmd_sync_work later processes the entry, it attempts to execute
mesh_send_sync and its destroy callback mesh_send_start_complete using
the already freed mesh_tx pointer, leading to a use-after-free.

Fix this by invoking hci_cmd_sync_dequeue() for mesh_send_sync on the
target mesh_tx before completing it.  If the entry is found and dequeued,
its destroy callback will complete and free the object; otherwise,
mesh_send_complete() is called directly.

Additionally, ensure the transmission queue advances after cancellation
or errors.  In mesh_send_start_complete(), call mesh_next() on error
unless err is -ECANCELED, because hci_cmd_sync_dequeue() holds
hdev->cmd_sync_work_lock and calling mesh_next() synchronously would
deadlock.  Instead, advance the queue in send_cancel() once the lock is
released and if no transmission is in progress.