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| author | Maxim Levitsky <mlevitsk@redhat.com> | 2022-11-03 17:13:44 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-11-17 19:39:54 +0300 |
| commit | 16ae56d7e0528559bf8dc9070e3bfd8ba3de80df (patch) | |
| tree | 58164c77de5374af858ca156f283bebe80bd5de2 /arch/x86/kvm/svm/nested.c | |
| parent | 917401f26a6af5756d89b550a8e1bd50cf42b07e (diff) | |
| download | linux-16ae56d7e0528559bf8dc9070e3bfd8ba3de80df.tar.xz | |
KVM: x86: nSVM: harden svm_free_nested against freeing vmcb02 while still in use
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>
Message-Id: <20221103141351.50662-3-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/svm/nested.c')
| -rw-r--r-- | arch/x86/kvm/svm/nested.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 4c620999d230..b02a3a1792f1 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -1125,6 +1125,9 @@ 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; |