Re: [PATCH v1 9/9] selftests: kvm: s390: Verify reject memory region operations for ucontrol VMs

[Claudio Imbrenda]

On Tue,  9 Jul 2024 14:57:04 +0200
Christoph Schlameuss <schlame...@linux.ibm.com> wrote:

> Add a test case verifying KVM_SET_USER_MEMORY_REGION and
> KVM_SET_USER_MEMORY_REGION2 cannot be executed on ucontrol VMs.
> 
> Executing this test case on not patched kernels will cause a null
> pointer dereference in the host kernel.

please add a reference to the patch that fixes the bug

> 
> Signed-off-by: Christoph Schlameuss <schlame...@linux.ibm.com>
> ---
>  .../selftests/kvm/s390x/ucontrol_test.c       | 22 +++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/tools/testing/selftests/kvm/s390x/ucontrol_test.c 
> b/tools/testing/selftests/kvm/s390x/ucontrol_test.c
> index 64ad31f667e3..a6f8a51519f8 100644
> --- a/tools/testing/selftests/kvm/s390x/ucontrol_test.c
> +++ b/tools/testing/selftests/kvm/s390x/ucontrol_test.c
> @@ -587,4 +587,26 @@ TEST_F(uc_kvm, uc_gprs)
>       ASSERT_EQ(1, sync_regs->gprs[0]);
>  }
>  
> +TEST_F(uc_kvm, uc_no_user_region)
> +{
> +     struct kvm_userspace_memory_region region = {
> +             .slot = 1,
> +             .guest_phys_addr = self->code_gpa,
> +             .memory_size = VM_MEM_EXT_SIZE,
> +             .userspace_addr = (uintptr_t)self->code_hva,
> +     };
> +     struct kvm_userspace_memory_region2 region2 = {
> +             .slot = 1,
> +             .guest_phys_addr = self->code_gpa,
> +             .memory_size = VM_MEM_EXT_SIZE,
> +             .userspace_addr = (uintptr_t)self->code_hva,
> +     };
> +
> +     ASSERT_EQ(-1, ioctl(self->vm_fd, KVM_SET_USER_MEMORY_REGION, &region));
> +     ASSERT_EQ(EINVAL, errno);
> +
> +     ASSERT_EQ(-1, ioctl(self->vm_fd, KVM_SET_USER_MEMORY_REGION2, 
> &region2));
> +     ASSERT_EQ(EINVAL, errno);
> +}
> +
>  TEST_HARNESS_MAIN