CVE-2026-89805

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

drm/pagemap: Fix folio allocation fallback and use-after-put

drm_pagemap_migrate_populate_ram_pfn() had two issues when populating

RAM PFNs with higher-order folios:

1. The higher-order vma_alloc_folio()/folio_alloc() calls did not pass

__GFP_NOWARN, so a THP allocation failure under memory pressure

would spam the kernel log, and there was no fallback path despite a

TODO comment stating one was needed. Add __GFP_NOWARN to the

higher-order allocation and, on failure, fall back to order-0

allocations for the entire range originally covered by the failed

higher-order allocation, leaving MIGRATE_PFN_COMPOUND unset for

those PFNs.

2. In the free_pages error path, order was computed via

folio_order(page_folio(page)) *after* put_page(page) had already

dropped the reference, resulting in a use-after-free/put when that

was the last reference on the page. Compute order before releasing

the pa

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References