Improper Locking The advisory has been revoked - it doesn't affect any version of package libperf  (opens in a new tab)


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  • Snyk IDSNYK-ALMALINUX10-LIBPERF-14120547
  • published26 Nov 2025
  • disclosed11 Nov 2025

Introduced: 11 Nov 2025

CVE-2025-21851  (opens in a new tab)
CWE-667  (opens in a new tab)

Amendment

The AlmaLinux security team deemed this advisory irrelevant for AlmaLinux:10.

NVD Description

Note: Versions mentioned in the description apply only to the upstream libperf package and not the libperf package as distributed by AlmaLinux.

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.