Bug 2454775 (CVE-2026-23421)

Summary: CVE-2026-23421 kernel: drm/xe/configfs: Free ctx_restore_mid_bb in release
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
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Version: unspecifiedKeywords: Security
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OS: Linux   
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A flaw was found in the Linux kernel. This vulnerability is a memory leak within the `drm/xe/configfs` subsystem, where allocated memory for `ctx_restore_mid_bb` is not properly released when a `configfs` device is removed. A local attacker could exploit this by repeatedly creating and removing `configfs` devices, leading to a gradual depletion of system memory. This could result in system instability or a denial of service (DoS) condition.
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Description OSIDB Bzimport 2026-04-03 14:01:47 UTC 
In the Linux kernel, the following vulnerability has been resolved:

drm/xe/configfs: Free ctx_restore_mid_bb in release

ctx_restore_mid_bb memory is allocated in wa_bb_store(), but
xe_config_device_release() only frees ctx_restore_post_bb.

Free ctx_restore_mid_bb[0].cs as well to avoid leaking the allocation
when the configfs device is removed.

(cherry picked from commit a235e7d0098337c3f2d1e8f3610c719a589e115f)
Comment 1 Alexander B 2026-04-03 15:04:05 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026040304-CVE-2026-23421-dace@gregkh/T