Message ID | 20221103135736.42295-3-mlevitsk@redhat.com |
---|---|
State | Accepted |
Commit | 16ae56d7e0528559bf8dc9070e3bfd8ba3de80df |
Headers | show |
Series | nSVM: Security and correctness fixes | expand |
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index b258d6988f5dde..b74da40c1fc40c 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -1126,6 +1126,9 @@ void svm_free_nested(struct vcpu_svm *svm) if (!svm->nested.initialized) return; + if (WARN_ON_ONCE(svm->vmcb != svm->vmcb01.ptr)) + svm_switch_vmcb(svm, &svm->vmcb01); + svm_vcpu_free_msrpm(svm->nested.msrpm); svm->nested.msrpm = NULL;
Make sure that KVM uses vmcb01 before freeing nested state, and warn if that is not the case. This is a minimal fix for CVE-2022-3344 making the kernel print a warning instead of a kernel panic. Cc: stable@vger.kernel.org Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> --- arch/x86/kvm/svm/nested.c | 3 +++ 1 file changed, 3 insertions(+)