CVE-2026-98149

Beschreibung

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix percpu map update indexing with sparse CPU IDs Per-CPU array, hash, and cgroup storage map updates without BPF_F_CPU or BPF_F_ALL_CPUS use a value buffer whose per-CPU slots are packed in possible-CPU order. The buffer is sized as: round_up(value_size, 8) * num_possible_cpus() The update paths iterate over possible CPUs, but use the logical CPU ID to calculate the source offset: value + size * cpu This only works when possible CPU IDs are contiguous starting at zero. For example, with a possible CPU mask of 0,2-3, the buffer contains three slots corresponding to CPUs 0, 2, and 3. CPU2 is therefore expected to use slot 1 and CPU3 slot 2. Instead, the current code uses slots 2 and 3 respectively, causing incorrect per-CPU values and an out-of-bounds read from the update buffer for CPU3. The corresponding lookup paths already use a dense offset while iterating over possible CPUs. Do the same for the array, hash, and cgroup storage update paths, advancing the source offset once for each possible CPU. BPF_F_ALL_CPUS continues to use the same value for every CPU.

Details

Hersteller

Linux

Produkt

Linux

Schwachstellentyp

CWE-125 (öffnet in einem neuen Tab)

Status

Analysiert

Aktualisiert

21. Okt. 2026

Zugewiesen von

416baaa9-dc9f-4396-8d5f-8c081fb06d67

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H