In the Linux kernel, the following vulnerability has been resolved:

bpf: Use array_map_meta_equal for percpu array inner map replacement

percpu_array_map_ops.map_meta_equal points to the generic
bpf_map_meta_equal(), which does not compare max_entries. When a
percpu array serves as an inner map, replacing it with one that has
fewer max_entries bypasses the check. Since percpu_array_map_gen_lookup()
inlines the original template's index_mask as a JIT immediate, a lookup
on the replacement map can access pptrs[] out of bounds.

Point percpu_array_map_ops.map_meta_equal to array_map_meta_equal(),
which already enforces the max_entries equality check.

Add a selftest to verify that replacing a percpu array inner map with
a differently-sized one is rejected.

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Fri, 09 Oct 2026 08:00:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: bpf: Use array_map_meta_equal for percpu array inner map replacement percpu_array_map_ops.map_meta_equal points to the generic bpf_map_meta_equal(), which does not compare max_entries. When a percpu array serves as an inner map, replacing it with one that has fewer max_entries bypasses the check. Since percpu_array_map_gen_lookup() inlines the original template's index_mask as a JIT immediate, a lookup on the replacement map can access pptrs[] out of bounds. Point percpu_array_map_ops.map_meta_equal to array_map_meta_equal(), which already enforces the max_entries equality check. Add a selftest to verify that replacing a percpu array inner map with a differently-sized one is rejected.
Title bpf: Use array_map_meta_equal for percpu array inner map replacement
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-10-09T07:34:17.043Z

Reserved: 2026-09-25T10:25:14.345Z

Link: CVE-2026-98376

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-09T08:16:55.910

Modified: 2026-10-09T08:16:55.910

Link: CVE-2026-98376

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

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