[PATCH v3 3/3] KVM: x86: SGX must obey the KVM_INTERNAL_ERROR_EMULATION protocol

From: David Edmondson
Date: Thu Jul 29 2021 - 09:46:11 EST


When passing the failing address and size out to user space, SGX must
ensure not to trample on the earlier fields of the emulation_failure
sub-union of struct kvm_run.

Signed-off-by: David Edmondson <david.edmondson@xxxxxxxxxx>
---
arch/x86/kvm/vmx/sgx.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/vmx/sgx.c b/arch/x86/kvm/vmx/sgx.c
index 6693ebdc0770..63fb93163383 100644
--- a/arch/x86/kvm/vmx/sgx.c
+++ b/arch/x86/kvm/vmx/sgx.c
@@ -53,11 +53,9 @@ static int sgx_get_encls_gva(struct kvm_vcpu *vcpu, unsigned long offset,
static void sgx_handle_emulation_failure(struct kvm_vcpu *vcpu, u64 addr,
unsigned int size)
{
- vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
- vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
- vcpu->run->internal.ndata = 2;
- vcpu->run->internal.data[0] = addr;
- vcpu->run->internal.data[1] = size;
+ uint64_t data[2] = { addr, size };
+
+ kvm_prepare_emulation_failure_exit(vcpu, false, data, sizeof(data));
}

static int sgx_read_hva(struct kvm_vcpu *vcpu, unsigned long hva, void *data,
--
2.30.2