CVE-2025-21851

3.3 LOW
Published: March 12, 2025 Modified: October 01, 2025

Description

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix softlockup in arena_map_free on 64k page kernel On an aarch64 kernel with CONFIG_PAGE_SIZE_64KB=y, arena_htab tests cause a segmentation fault and soft lockup. The same failure is not observed with 4k pages on aarch64. It turns out arena_map_free() is calling apply_to_existing_page_range() with the address returned by bpf_arena_get_kern_vm_start(). If this address is not page-aligned the code ends up calling apply_to_pte_range() with that unaligned address causing soft lockup. Fix it by round up GUARD_SZ to PAGE_SIZE << 1 so that the division by 2 in bpf_arena_get_kern_vm_start() returns a page-aligned value.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://git.kernel.org/stable/c/517e8a7835e8cfb398a0aeb0133de50e31cae32b
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/787d556a3de447e70964a4bdeba9196f62a62b1e
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/c1f3f3892d4526f18aaeffdb6068ce861e793ee3
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch

3 reference(s) from NVD

Quick Stats

CVSS v3 Score
3.3 / 10.0
EPSS (Exploit Probability)
0.0%
6th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

linux