Bug 2395314 (CVE-2022-50274)

Summary: CVE-2022-50274 kernel: media: dvbdev: adopts refcnt to avoid UAF
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
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OS: Linux   
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Description OSIDB Bzimport 2025-09-15 15:06:58 UTC 
In the Linux kernel, the following vulnerability has been resolved:

media: dvbdev: adopts refcnt to avoid UAF

dvb_unregister_device() is known that prone to use-after-free.
That is, the cleanup from dvb_unregister_device() releases the dvb_device
even if there are pointers stored in file->private_data still refer to it.

This patch adds a reference counter into struct dvb_device and delays its
deallocation until no pointer refers to the object.
Comment 1 Jon Moroney 2025-09-15 22:58:23 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025091505-CVE-2022-50274-ad8d@gregkh/T