Bug 2492360 (CVE-2026-52949)

Summary: CVE-2026-52949 kernel: drm/ttm: Fix ttm_bo_shrink() infinite LRU walk on backup failure
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in the Linux kernel's Direct Rendering Manager (DRM) subsystem. Specifically, within the `ttm_bo_shrink()` function, a backup failure could lead to an infinite Least Recently Used (LRU) walk. This issue may allow a local attacker to trigger a Denial of Service (DoS), making the system unresponsive.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-06-24 18:07:49 UTC
In the Linux kernel, the following vulnerability has been resolved:

drm/ttm: Fix ttm_bo_shrink() infinite LRU walk on backup failure

Apply the same fix as b2ed01e7ad ("drm/ttm: Fix ttm_bo_swapout()
infinite LRU walk on swapout failure") to the ttm_bo_shrink() path.

Move del_bulk_move from before the backup to after success only,
using ttm_resource_del_bulk_move_unevictable() since the resource
is now unevictable once fully backed up.