diff options
author | Ladi Prosek <lprosek@redhat.com> | 2017-10-05 11:10:22 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-18 09:35:42 +0200 |
commit | 28955b03fac36829831e185e3ec2793f8eb18689 (patch) | |
tree | d3588cb05d3c35fe51586a76686713274ee0e307 | |
parent | fb6da44f965e7cba7874e70b56bce540946c8104 (diff) |
KVM: nVMX: update last_nonleaf_level when initializing nested EPT
commit fd19d3b45164466a4adce7cbff448ba9189e1427 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | arch/x86/kvm/mmu.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index ea3f8f774208..d29c745f10ad 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -4169,6 +4169,7 @@ 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); } |