6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Oliver Upton <oliver.upton@xxxxxxxxx> [ Upstream commit 160933e330f4c5a13931d725a4d952a4b9aefa71 ] Assert that accesses to a non-existent vgic-v2 CPU interface consistently fail across the various KVM device attr ioctls. This also serves as a regression test for a bug wherein KVM hits a NULL dereference when the CPUID specified in the ioctl is invalid. Note that there is no need to print the observed errno, as TEST_ASSERT() will take care of it. Reviewed-by: Marc Zyngier <maz@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240424173959.3776798-3-oliver.upton@xxxxxxxxx Signed-off-by: Oliver Upton <oliver.upton@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/testing/selftests/kvm/aarch64/vgic_init.c | 50 ++++++++++++++++++++++++ 1 file changed, 50 insertions(+) --- a/tools/testing/selftests/kvm/aarch64/vgic_init.c +++ b/tools/testing/selftests/kvm/aarch64/vgic_init.c @@ -6,6 +6,7 @@ */ #define _GNU_SOURCE #include <linux/kernel.h> +#include <linux/bitfield.h> #include <sys/syscall.h> #include <asm/kvm.h> #include <asm/kvm_para.h> @@ -84,6 +85,18 @@ static struct vm_gic vm_gic_create_with_ return v; } +static struct vm_gic vm_gic_create_barebones(uint32_t gic_dev_type) +{ + struct vm_gic v; + + v.gic_dev_type = gic_dev_type; + v.vm = vm_create_barebones(); + v.gic_fd = kvm_create_device(v.vm, gic_dev_type); + + return v; +} + + static void vm_gic_destroy(struct vm_gic *v) { close(v->gic_fd); @@ -357,6 +370,40 @@ static void test_vcpus_then_vgic(uint32_ vm_gic_destroy(&v); } +#define KVM_VGIC_V2_ATTR(offset, cpu) \ + (FIELD_PREP(KVM_DEV_ARM_VGIC_OFFSET_MASK, offset) | \ + FIELD_PREP(KVM_DEV_ARM_VGIC_CPUID_MASK, cpu)) + +#define GIC_CPU_CTRL 0x00 + +static void test_v2_uaccess_cpuif_no_vcpus(void) +{ + struct vm_gic v; + u64 val = 0; + int ret; + + v = vm_gic_create_barebones(KVM_DEV_TYPE_ARM_VGIC_V2); + subtest_dist_rdist(&v); + + ret = __kvm_has_device_attr(v.gic_fd, KVM_DEV_ARM_VGIC_GRP_CPU_REGS, + KVM_VGIC_V2_ATTR(GIC_CPU_CTRL, 0)); + TEST_ASSERT(ret && errno == EINVAL, + "accessed non-existent CPU interface, want errno: %i", + EINVAL); + ret = __kvm_device_attr_get(v.gic_fd, KVM_DEV_ARM_VGIC_GRP_CPU_REGS, + KVM_VGIC_V2_ATTR(GIC_CPU_CTRL, 0), &val); + TEST_ASSERT(ret && errno == EINVAL, + "accessed non-existent CPU interface, want errno: %i", + EINVAL); + ret = __kvm_device_attr_set(v.gic_fd, KVM_DEV_ARM_VGIC_GRP_CPU_REGS, + KVM_VGIC_V2_ATTR(GIC_CPU_CTRL, 0), &val); + TEST_ASSERT(ret && errno == EINVAL, + "accessed non-existent CPU interface, want errno: %i", + EINVAL); + + vm_gic_destroy(&v); +} + static void test_v3_new_redist_regions(void) { struct kvm_vcpu *vcpus[NR_VCPUS]; @@ -675,6 +722,9 @@ void run_tests(uint32_t gic_dev_type) test_vcpus_then_vgic(gic_dev_type); test_vgic_then_vcpus(gic_dev_type); + if (VGIC_DEV_IS_V2(gic_dev_type)) + test_v2_uaccess_cpuif_no_vcpus(); + if (VGIC_DEV_IS_V3(gic_dev_type)) { test_v3_new_redist_regions(); test_v3_typer_accesses();
