summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLadi Prosek <lprosek@redhat.com>2017-10-05 11:10:22 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-10-18 09:35:42 +0200
commit28955b03fac36829831e185e3ec2793f8eb18689 (patch)
treed3588cb05d3c35fe51586a76686713274ee0e307
parentfb6da44f965e7cba7874e70b56bce540946c8104 (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.c1
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);
}