Commit 181f4948 authored by Michael Roth's avatar Michael Roth Committed by Paolo Bonzini
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KVM: x86: fix CPUID entries returned by KVM_GET_CPUID2 ioctl 



Recent commit 255cbecf modified struct kvm_vcpu_arch to make
'cpuid_entries' a pointer to an array of kvm_cpuid_entry2 entries
rather than embedding the array in the struct. KVM_SET_CPUID and
KVM_SET_CPUID2 were updated accordingly, but KVM_GET_CPUID2 was missed.

As a result, KVM_GET_CPUID2 currently returns random fields from struct
kvm_vcpu_arch to userspace rather than the expected CPUID values. Fix
this by treating 'cpuid_entries' as a pointer when copying its
contents to userspace buffer.

Fixes: 255cbecf ("KVM: x86: allocate vcpu->arch.cpuid_entries dynamically")
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: default avatarMichael Roth <michael.roth@amd.com.com>
Message-Id: <20210128024451.1816770-1-michael.roth@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 9a78e158

arch/x86/kvm/cpuid.c

+1 −1
Original line number Diff line number Diff line
@@ -321,7 +321,7 @@ int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu, 
	if (cpuid->nent < vcpu->arch.cpuid_nent)

		goto out;

	r = -EFAULT;

	if (copy_to_user(entries, &vcpu->arch.cpuid_entries,

	if (copy_to_user(entries, vcpu->arch.cpuid_entries,

			 vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))

		goto out;

	return 0;