diff options
| author | Sean Christopherson <seanjc@google.com> | 2021-03-30 20:19:36 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-04-17 08:30:58 -0400 |
| commit | 8727906fde6ea665b52e68ddc58833772537f40a (patch) | |
| tree | 4d7bcb868fb8cdf87883a0fa38a9158f86bfdbe3 | |
| parent | 9fa1521daafb58d878d03d75f6863a11312fae22 (diff) | |
KVM: SVM: Do not allow SEV/SEV-ES initialization after vCPUs are created
Reject KVM_SEV_INIT and KVM_SEV_ES_INIT if they are attempted after one
or more vCPUs have been created. KVM assumes a VM is tagged SEV/SEV-ES
prior to vCPU creation, e.g. init_vmcb() needs to mark the VMCB as SEV
enabled, and svm_create_vcpu() needs to allocate the VMSA. At best,
creating vCPUs before SEV/SEV-ES init will lead to unexpected errors
and/or behavior, and at worst it will crash the host, e.g.
sev_launch_update_vmsa() will dereference a null svm->vmsa pointer.
Fixes: 1654efcbc431 ("KVM: SVM: Add KVM_SEV_INIT command")
Fixes: ad73109ae7ec ("KVM: SVM: Provide support to launch and run an SEV-ES guest")
Cc: stable@vger.kernel.org
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210331031936.2495277-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | arch/x86/kvm/svm/sev.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index 97d42a007b86..824bc7d22e77 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -182,6 +182,9 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) bool es_active = argp->id == KVM_SEV_ES_INIT; int asid, ret; + if (kvm->created_vcpus) + return -EINVAL; + ret = -EBUSY; if (unlikely(sev->active)) return ret; |