Bug 2482019 (CVE-2026-46047)

Summary: CVE-2026-46047 kernel: net: qrtr: ns: Fix use-after-free in driver remove()
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
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Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the Linux kernel's `qrtr` networking driver. During the driver's removal process, a timing issue can occur if a packet arrives after the work queue is destroyed but before the socket is released. This can cause the system to attempt to access memory that has already been freed, leading to a use-after-free vulnerability. Such a vulnerability can result in system instability or a denial of service.
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Description OSIDB Bzimport 2026-05-27 15:07:21 UTC 
In the Linux kernel, the following vulnerability has been resolved:

net: qrtr: ns: Fix use-after-free in driver remove()

In the remove callback, if a packet arrives after destroy_workqueue() is
called, but before sock_release(), the qrtr_ns_data_ready() callback will
try to queue the work, causing use-after-free issue.

Fix this issue by saving the default 'sk_data_ready' callback during
qrtr_ns_init() and use it to replace the qrtr_ns_data_ready() callback at
the start of remove(). This ensures that even if a packet arrives after
destroy_workqueue(), the work struct will not be dereferenced.

Note that it is also required to ensure that the RX threads are completed
before destroying the workqueue, because the threads could be using the
qrtr_ns_data_ready() callback.
Comment 1 Keith Grant 2026-05-27 19:23:10 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026052752-CVE-2026-46047-5701@gregkh/T