CVE-2026-43286

Popis

In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: restore failed global reservations to subpool Commit a833a693a490 (-mm: hugetlb: fix incorrect fallback for subpool-) fixed an underflow error for hstate->resv_huge_pages caused by incorrectly attributing globally requested pages to the subpool-s reservation. Unfortunately, this fix also introduced the opposite problem, which would leave spool->used_hpages elevated if the globally requested pages could not be acquired. This is because while a subpool-s reserve pages only accounts for what is requested and allocated from the subpool, its -used- counter keeps track of what is consumed in total, both from the subpool and globally. Thus, we need to adjust spool->used_hpages in the other direction, and make sure that globally requested pages are uncharged from the subpool-s used counter. Each failed allocation attempt increments the used_hpages counter by how many pages were requested from the global pool. Ultim...