Bug 2536295 (CVE-2026-90255)

Summary: CVE-2026-90255 kernel: Bluetooth: hci_conn: fix the SCO setup context lifetime
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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. Specifically, a resource leak occurs in the handling of Synchronous Connection-Oriented (SCO) setup contexts. If a setup entry is cancelled, its associated context is not properly released, leading to a memory leak. This issue could also result in a use-after-free condition if a Bluetooth connection is freed while its pointer is still referenced in a queued work item, potentially leading to system instability or a denial of service.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-17 17:16:51 UTC
In the Linux kernel, the following vulnerability has been resolved:

Bluetooth: hci_conn: fix the SCO setup context lifetime

hci_setup_sync() queues a conn_handle_t with a NULL destroy callback, so
the context is only freed if hci_enhanced_setup_sync() actually runs. An
entry that is cancelled instead is leaked, as
_hci_cmd_sync_cancel_entry() does not release entry->data when there is
no destroy callback, and hci_cmd_sync_clear() cancels every pending entry
when the controller is unregistered.

The context also stores a bare hci_conn pointer, so the connection can be
freed while the work is queued. The dequeue in hci_conn_del() does not
cover it either, as it matches on entry->data == conn and entry->data is
the wrapper here. Same problem as commit 2f5d635ad590 ("Bluetooth:
hci_sync: hold conn in hci_connect_acl/le_sync() callbacks").

Hold the connection and release both from a destroy callback. The
submission failure path drops both, since hci_cmd_sync_submit() does not
call the destroy callback when it fails to queue.