CVSS
Вероятност да бъде експлоатирана в следващите 30 дни (EPSS)
Атакува се
Време до експлоатация
Описание
Оригинално описание
In the Linux kernel, the following vulnerability has been resolved: cpu/hotplug: Fix NULL kobject warning in cpuhp_smt_enable() On arm64, when booting with `maxcpus` greater than the number of present CPUs (e.g., QEMU -smp cpus=4,maxcpus=8), some CPUs are marked as 'present' but have not yet been registered via register_cpu(). Consequently, the per-cpu device objects for these CPUs are not yet initialized. In cpuhp_smt_enable(), the code iterates over all present CPUs. Calling _cpu_up() for these unregistered CPUs eventually leads to sysfs_create_group() being called with a NULL kobject (or a kobject without a directory), triggering the following warning in fs/sysfs/group.c: WARNING: fs/sysfs/group.c:137 at internal_create_group+0x41c/0x4bc, CPU#2: sh/181 [...] Call trace: internal_create_group+0x41c/0x4bc (P) sysfs_create_group+0x18/0x24 topology_add_dev+0x1c/0x28 cpuhp_invoke_callback+0x104/0x20c __cpuhp_invoke_callback_range+0x94/0x11c _cpu_up+0x200/0x37c When booting with ACPI, arm64 smp_prepare_cpus() currently sets all enumerated CPUs as "present" regardless of their status in the MADT. This causes issues with SMT hotplug control. For instance, with QEMU's "-smp 4,maxcpus=8" configuration, the MADT GICC entries are populated as follows: 1. The first four CPUs: `Enabled` set but `Online Capable` not set. 2. The remaining four CPUs: `Online Capable` set but `Enabled` not set to support potential hot-plugging. Fix this by: 1. When booting with ACPI, checking the ACPI_MADT_ENABLED flag in the GICC entry before calling set_cpu_present() during SMP initialization. 2. Properly managing the present mask in acpi_map_cpu() and acpi_unmap_cpu() to support actual CPU hotplug events, This aligns with other architectures like x86 and LoongArch. 3. Update the arm64 CPU hotplug documentation to no longer state that all online-capable vCPUs are marked as present by the kernel at boot time. This ensures that only physical
Засегнати продукти
- Linux Linux: eed4583bcf9a60f8d6dd3a3c7c94dea28134b1eb преди ccdf1770a4ba27e31599d24ad970d77a371c7912; eed4583bcf9a60f8d6dd3a3c7c94dea28134b1eb преди 901a489d89ee9c854624c8444090e38e70aed234; eed4583bcf9a60f8d6dd3a3c7c94dea28134b1eb преди f9a82544c7174851f5c7524622f5966dcafd3a47
- Linux Linux: 6.15; преди 6.15; 6.18.40 до 6.18.*; 7.1.5 до 7.1.*; 7.2 до *
История
- 15 август 2026 Публикувано
Други уязвимости в Linux Linux
Първоизточници
- https://www.cve.org/CVERecord?id=CVE-2026-72016
- https://nvd.nist.gov/vuln/detail/CVE-2026-72016
- https://git.kernel.org/stable/c/ccdf1770a4ba27e31599d24ad970d77a371c7912
- https://git.kernel.org/stable/c/901a489d89ee9c854624c8444090e38e70aed234
- https://git.kernel.org/stable/c/f9a82544c7174851f5c7524622f5966dcafd3a47