From: Jonathan Cameron <Jonathan.Cameron@huawei.com> mainline inclusion from mainline-v6.11-rc1 commit 2488444274c70038eb6b686cba5f1ce48ebb9cdd category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAU9OA CVE: CVE-2024-46822 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- In a review discussion of the changes to support vCPU hotplug where a check was added on the GICC being enabled if was online, it was noted that there is need to map back to the cpu and use that to index into a cpumask. As such, a valid ID is needed. If an MPIDR check fails in acpi_map_gic_cpu_interface() it is possible for the entry in cpu_madt_gicc[cpu] == NULL. This function would then cause a NULL pointer dereference. Whilst a path to trigger this has not been established, harden this caller against the possibility. Reviewed-by: Gavin Shan <gshan@redhat.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/20240529133446.28446-13-Jonathan.Cameron@huawei.co... Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: wangheyuan <wangheyuan2@h-partners.com> --- arch/arm64/include/asm/acpi.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index bc9a6656fc0c..a407f9cd549e 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -124,7 +124,8 @@ static inline int get_cpu_for_acpi_id(u32 uid) int cpu; for (cpu = 0; cpu < nr_cpu_ids; cpu++) - if (uid == get_acpi_id_for_cpu(cpu)) + if (acpi_cpu_get_madt_gicc(cpu) && + uid == get_acpi_id_for_cpu(cpu)) return cpu; return -EINVAL; -- 2.25.1