Commit 160933e3 authored by Oliver Upton's avatar Oliver Upton
Browse files

KVM: selftests: Add test for uaccesses to non-existent vgic-v2 CPUIF 



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: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20240424173959.3776798-3-oliver.upton@linux.dev


Signed-off-by: default avatarOliver Upton <oliver.upton@linux.dev>
parent 6ddb4f37

tools/testing/selftests/kvm/aarch64/vgic_init.c

+49 −0
Original line number Diff line number Diff line
@@ -84,6 +84,18 @@ static struct vm_gic vm_gic_create_with_vcpus(uint32_t gic_dev_type, 
	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 +369,40 @@ static void test_vcpus_then_vgic(uint32_t gic_dev_type) 
	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 +721,9 @@ 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();