Paper/Archive/CVE-2026-31589

CVE-2026-31589

Linux Linux — mm: call ->free_folio() directly in folio_unmap_invalidate()

Description · from the CVE record

In the Linux kernel, the following vulnerability has been resolved: mm: call ->free_folio() directly in folio_unmap_invalidate() We can only call filemap_free_folio() if we have a reference to (or hold a lock on) the mapping. Otherwise, we've already removed the folio from the mapping so it no longer pins the mapping and the mapping can be removed, causing a use-after-free when accessing mapping->a_ops. Follow the same pattern as __remove_mapping() and load the free_folio function pointer before dropping the lock on the mapping. That lets us make filemap_free_folio() static as this was the only caller outside filemap.c.

Affected

ProductAffectedFixed inSource
Linuxfb7d3bc4149395c1ae99029c852eab6c28fc3c88 – < efc52947247a21bbf79059539bbbd40f4ea76f00efc52947247a21bbf79059539bbbd40f4ea76f00CNA
Linuxfb7d3bc4149395c1ae99029c852eab6c28fc3c88 – < b667df39d98a7a24be7c2a40ff0863dac1ad2cd7b667df39d98a7a24be7c2a40ff0863dac1ad2cd7CNA
Linuxfb7d3bc4149395c1ae99029c852eab6c28fc3c88 – < c330e65ea59c4805d6ab6757c4ddfe8c63acef31c330e65ea59c4805d6ab6757c4ddfe8c63acef31CNA
Linuxfb7d3bc4149395c1ae99029c852eab6c28fc3c88 – < 615d9bb2ccad42f9e21d837431e401db2e471195615d9bb2ccad42f9e21d837431e401db2e471195CNA
Linux6.146.18.27CNA

Scores by source

Linux (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References

refgit.kernel.org/stable/c/efc52947247a21bbf79059539bbbd40f4ea76f00refgit.kernel.org/stable/c/b667df39d98a7a24be7c2a40ff0863dac1ad2cd7refgit.kernel.org/stable/c/c330e65ea59c4805d6ab6757c4ddfe8c63acef31refgit.kernel.org/stable/c/615d9bb2ccad42f9e21d837431e401db2e471195