CVE-2025-71134

/// Technical description

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

mm/page_alloc: change all pageblocks migrate type on coalescing

When a page is freed it coalesces with a buddy into a higher order page

while possible. When the buddy page migrate type differs, it is expected

to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the

rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),

since an inconsistency between migration type of the list containing the

page and the page-owned pageblocks migration types is introduced.

[ 308.986589] ------------[ cut here ]------------

[ 308.987227] page type is 0, passed migratetype is 1 (nr=256)

[ 308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270

[ 308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet

/// 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