CVEvulnerability
CVE-2025-37818
5.5 MEDIUM
Official page ↗
- Status
- Analyzed
- Published
- 2025-05-08
- Last modified
- 2026-06-17
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 ([email protected])
- 5.5 MEDIUM — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- CWE-476
Description
In the Linux kernel, the following vulnerability has been resolved:
LoongArch: Return NULL from huge_pte_offset() for invalid PMD
LoongArch's huge_pte_offset() currently returns a pointer to a PMD slot
even if the underlying entry points to invalid_pte_table (indicating no
mapping). Callers like smaps_hugetlb_range() fetch this invalid entry
value (the address of invalid_pte_table) via this pointer.
The generic is_swap_pte() check then incorrectly identifies this address
as a swap entry on LoongArch, because it satisfies the "!pte_present()
&& !pte_none()" conditions. This misinterpretation, combined with a
coincidental match by is_migration_entry() on the address bits, leads to
kernel crashes in pfn_swap_entry_to_page().
Fix this at the architecture level by modifying huge_pte_offset() to
check the PMD entry's content using pmd_none() before returning. If the
entry is invalid (i.e., it points to invalid_pte_table), return NULL
instead of the pointer to the slot.
Affected configurations
• linux linux kernel (>= 5.19 < 6.1.136)
• linux linux kernel (>= 6.2 < 6.6.89)
• linux linux kernel (>= 6.7 < 6.12.26)
• linux linux kernel (>= 6.13 < 6.14.5)
• linux linux kernel 6.15
• debian debian linux 11.0
Related
Weakness · CWE (1)
- CWE-476 NULL Pointer Dereference weakness
References
- https://git.kernel.org/stable/c/2ca9380b12711afe95b3589bd82b59623b3c96b3 Patch
- https://git.kernel.org/stable/c/34256805720993e37adf6127371a1265aea8376a Patch
- https://git.kernel.org/stable/c/51424fd171cee6a33f01f7c66b8eb23ac42289d4 Patch
- https://git.kernel.org/stable/c/b49f085cd671addbda4802d6b9382513f7dd0f30 Patch
- https://git.kernel.org/stable/c/bd51834d1cf65a2c801295d230c220aeebf87a73 Patch
- https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html Mailing List, Third Party Advisory