lkml.org 
[lkml]   [2017]   [Oct]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.13 53/53] KVM: nVMX: update last_nonleaf_level when initializing nested EPT
    Date
    4.13-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Ladi Prosek <lprosek@redhat.com>

    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>

    ---
    arch/x86/kvm/mmu.c | 1 +
    1 file changed, 1 insertion(+)

    --- a/arch/x86/kvm/mmu.c
    +++ b/arch/x86/kvm/mmu.c
    @@ -4459,6 +4459,7 @@ void kvm_init_shadow_ept_mmu(struct kvm_

    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);
    }

    \
     
     \ /
      Last update: 2017-10-16 18:24    [W:2.343 / U:0.144 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site