CVE-2025-21851
- Source
- https://cve.org/CVERecord?id=CVE-2025-21851
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-21851.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2025-21851
- Downstream
- Related
- Published
- 2025-03-12T09:42:06Z
- Modified
- 2026-08-12T03:30:24Z
- Severity
-
- 7.8 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
- Summary
- bpf: Fix softlockup in arena_map_free on 64k page kernel
- Details
-
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.
- Database specific
{ "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21851.json" }- References
-
- https://git.kernel.org/stable/c/517e8a7835e8cfb398a0aeb0133de50e31cae32b
- https://git.kernel.org/stable/c/787d556a3de447e70964a4bdeba9196f62a62b1e
- https://git.kernel.org/stable/c/c1f3f3892d4526f18aaeffdb6068ce861e793ee3
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21851.json
- https://nvd.nist.gov/vuln/detail/CVE-2025-21851
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git