CVE-2026-31575
In the Linux kernel, the following vulnerability has been resolved:
mm/userfaultfd: fix hugetlb fault mutex hash calculation
In mfill_atomic_hugetlb(), linear_page_index() is used to calculate the page index for hugetlb_fault_mutex_hash(). However, linear_page_index() returns the index in PAGE_SIZE units, while hugetlb_fault_mutex_hash() expects the index in huge page units. This mismatch means that different addresses within the same huge page can produce different hash values, leading to the use of different mutexes for the same huge page. This can cause races between faulting threads, which can corrupt the reservation map and trigger the BUG_ON in resv_map_release().
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Fix this by introducing hugetlb_linear_page_index(), which returns the page index in huge page granularity, and using it in place of linear_page_index().
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.16%
- Percentil entre todas las CVEs puntuadas: 5
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (1)
CWE
- NVD-CWE-noinfo
Referencias
- https://git.kernel.org/stable/c/0217c7fb4de4a40cee667eb21901f3204effe5ac
- https://git.kernel.org/stable/c/08282b1bf74c69fc8ecd25493e7fdb5460f01290
- https://git.kernel.org/stable/c/574501ede47ac439afd67ba9812bc66722d500ba
- https://git.kernel.org/stable/c/5a525c43baaba0bf3063f86996ca3623b71e4172
- https://git.kernel.org/stable/c/f4689fc089765d36c026063fb22d23533e883eb6
JSON original (NVD)
Mostrar
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