CVSS
Вероятност да бъде експлоатирана в следващите 30 дни (EPSS)
Атакува се
Време до експлоатация
Описание
Оригинално описание
In the Linux kernel, the following vulnerability has been resolved: fs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole() A PAGEMAP_SCAN ioctl requesting PM_SCAN_WP_MATCHING on a hugetlb VMA hangs the calling thread, unkillably, as soon as the scan reaches an unpopulated part of the range: do_pagemap_scan() walk_page_range() walk_hugetlb_range() hugetlb_vma_lock_read() # take the vma lock for read ... pagemap_scan_pte_hole() # ... ->pte_hole() for a hole uffd_wp_range() change_protection() hugetlb_change_protection() hugetlb_vma_lock_write() # ... and block taking it for write walk_hugetlb_range() holds the hugetlb vma lock for read across the whole walk. A present entry goes to ->hugetlb_entry(); an unpopulated one goes to ->pte_hole(), i.e. pagemap_scan_pte_hole(). To write-protect the hole that handler calls uffd_wp_range(), which on a hugetlb VMA reaches hugetlb_change_protection() and takes the same vma lock for write. The thread then blocks in down_write() waiting for the read lock it is itself holding. The populated path avoids this: pagemap_scan_hugetlb_entry() write-protects the entry inline under the page-table lock and never enters hugetlb_change_protection(). Do the same for holes. Fault in the page table and install the uffd-wp marker directly with make_uffd_wp_huge_pte() under the page-table lock, rather than routing through uffd_wp_range(). That is the same sequence hugetlb_change_protection() runs for an unpopulated entry, minus the vma write lock -- which is safe to skip because PMD sharing is disabled on uffd-wp VMAs (hugetlb_unshare_all_pmds() runs at registration), leaving nothing for that lock to serialise against.
Засегнати продукти
- Linux Linux: 52526ca7fdb905a768a93f8faa418e9b988fc34b преди a6ac03652d9edc30c2912037ac83beb42cc67f8e; 52526ca7fdb905a768a93f8faa418e9b988fc34b преди 43b987ed35be9be21a303d1036d4241fec9943df; 52526ca7fdb905a768a93f8faa418e9b988fc34b преди 18b8a9700610299819d21fd0ea85d24726d17f65; 52526ca7fdb905a768a93f8faa418e9b988fc34b преди e92d92bbafb264dc0518d52b846a3c07ed8d523f
- Linux Linux: 6.7; преди 6.7; 6.12.97 до 6.12.*; 6.18.40 до 6.18.*; 7.1.5 до 7.1.*; от 7.2 нататък
История
- 15 август 2026 Публикувано
Други уязвимости в Linux Linux
Първоизточници
- https://www.cve.org/CVERecord?id=CVE-2026-72174
- https://nvd.nist.gov/vuln/detail/CVE-2026-72174
- https://git.kernel.org/stable/c/a6ac03652d9edc30c2912037ac83beb42cc67f8e
- https://git.kernel.org/stable/c/43b987ed35be9be21a303d1036d4241fec9943df
- https://git.kernel.org/stable/c/18b8a9700610299819d21fd0ea85d24726d17f65
- https://git.kernel.org/stable/c/e92d92bbafb264dc0518d52b846a3c07ed8d523f