[PATCH 0/2] KVM: nVMX: Fix a (benign) overwrite to a userspace buffer

[Sean Christopherson <seanjc@google.com>]

Fix a bug where KVM writes more bytes for KVM_GET_NESTED_STATE than it reports
in the output size if L1 is active and has a valid shadow VMCS pointer.  The
bug is all but guaranteed to be benign in practice, as all VMMs I could find
that support nested virtualization just preallocate the max buffer size.

Sean Christopherson (2):
  KVM: nVMX: Save shadow VMCS when getting nested state iff L2 is active
  KVM: selftests: Add regression test for KVM writing but not reporting
    vmcs12

 arch/x86/kvm/vmx/nested.c                     |  2 +-
 .../testing/selftests/kvm/lib/x86/processor.c |  6 +++++
 tools/testing/selftests/kvm/x86/state_test.c  | 24 ++++++++++---------
 3 files changed, 20 insertions(+), 12 deletions(-)


base-commit: 164405e8e9a0378c7e1aff2254625a6553a291f1
-- 
2.56.0.218.g1ec904b173-goog