tools/testing/selftests/kvm/set_sregs_test.c

   1 /*
   2  * KVM_SET_SREGS tests
   3  *
   4  * Copyright (C) 2018, Google LLC.
   5  *
   6  * This work is licensed under the terms of the GNU GPL, version 2.
   7  *
   8  * This is a regression test for the bug fixed by the following commit:
   9  * d3802286fa0f ("kvm: x86: Disallow illegal IA32_APIC_BASE MSR values")
  10  *
  11  * That bug allowed a user-mode program that called the KVM_SET_SREGS
  12  * ioctl to put a VCPU's local APIC into an invalid state.
  13  *
  14  */
  15 #define _GNU_SOURCE /* for program_invocation_short_name */
  16 #include <fcntl.h>
  17 #include <stdio.h>
  18 #include <stdlib.h>
  19 #include <string.h>
  20 #include <sys/ioctl.h>
  21
  22 #include "test_util.h"
  23
  24 #include "kvm_util.h"
  25 #include "x86.h"
  26
  27 #define VCPU_ID                  5
  28
  29 int main(int argc, char *argv[])
  30 {
  31         struct kvm_sregs sregs;
  32         struct kvm_vm *vm;
  33         int rc;
  34
  35         /* Tell stdout not to buffer its content */
  36         setbuf(stdout, NULL);
  37
  38         /* Create VM */
  39         vm = vm_create_default(VCPU_ID, 0, NULL);
  40
  41         vcpu_sregs_get(vm, VCPU_ID, &sregs);
  42         sregs.apic_base = 1 << 10;
  43         rc = _vcpu_sregs_set(vm, VCPU_ID, &sregs);
  44         TEST_ASSERT(rc, "Set IA32_APIC_BASE to %llx (invalid)",
  45                     sregs.apic_base);
  46         sregs.apic_base = 1 << 11;
  47         rc = _vcpu_sregs_set(vm, VCPU_ID, &sregs);
  48         TEST_ASSERT(!rc, "Couldn't set IA32_APIC_BASE to %llx (valid)",
  49                     sregs.apic_base);
  50
  51         kvm_vm_free(vm);
  52
  53         return 0;
  54 }