Message ID | 1508936039-21254-2-git-send-email-stefan.bader@canonical.com |
---|---|
State | New |
Headers | show |
Series | [1/2] KVM: nVMX: update last_nonleaf_level when initializing nested EPT | expand |
On 25/10/17 14:53, Stefan Bader wrote: > From: Ladi Prosek <lprosek@redhat.com> > > The function updates context->root_level but didn't call > update_last_nonleaf_level so the previous and potentially wrong value > was used for page walks. For example, a zero value of last_nonleaf_level > would allow a potential out-of-bounds access in arch/x86/mmu/paging_tmpl.h's > walk_addr_generic function (CVE-2017-12188). > > Fixes: 155a97a3d7c78b46cef6f1a973c831bc5a4f82bb > Signed-off-by: Ladi Prosek <lprosek@redhat.com> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > > CVE-2017-12188 > > (cherry-picked from commit fd19d3b45164466a4adce7cbff448ba9189e1427) > Signed-off-by: Stefan Bader <stefan.bader@canonical.com> > --- > arch/x86/kvm/mmu.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c > index 7012de4..1e8a0e0 100644 > --- a/arch/x86/kvm/mmu.c > +++ b/arch/x86/kvm/mmu.c > @@ -4158,6 +4158,7 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly) > > update_permission_bitmask(vcpu, context, true); > update_pkru_bitmask(vcpu, context, true); > + update_last_nonleaf_level(vcpu, context); > reset_rsvds_bits_mask_ept(vcpu, context, execonly); > reset_ept_shadow_zero_bits_mask(vcpu, context, execonly); > } > Clean cherry pick. Looks good. Acked-by: Colin Ian King <colin.king@canonical.com>
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 7012de4..1e8a0e0 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -4158,6 +4158,7 @@ void kvm_init_shadow_ept_mmu(struct kvm_vcpu *vcpu, bool execonly) update_permission_bitmask(vcpu, context, true); update_pkru_bitmask(vcpu, context, true); + update_last_nonleaf_level(vcpu, context); reset_rsvds_bits_mask_ept(vcpu, context, execonly); reset_ept_shadow_zero_bits_mask(vcpu, context, execonly); }