projects / pve-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| c0514fa3 | 1 | From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 |
| 2dc5b5fe TL |
2 | From: Felix Wilhelm <fwilhelm@google.com> |
| 3 | Date: Mon, 11 Jun 2018 09:43:44 +0200 | |
| c0514fa3 | 4 | Subject: [PATCH] kvm: nVMX: Enforce cpl=0 for VMX instructions |
| 2dc5b5fe TL |
5 | |
| 6 | VMX instructions executed inside a L1 VM will always trigger a VM exit | |
| 7 | even when executed with cpl 3. This means we must perform the | |
| 8 | privilege check in software. | |
| 9 | ||
| 10 | Fixes: 70f3aac964ae("kvm: nVMX: Remove superfluous VMX instruction fault checks") | |
| 11 | Cc: stable@vger.kernel.org | |
| 12 | Signed-off-by: Felix Wilhelm <fwilhelm@google.com> | |
| 13 | Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> | |
| 14 | Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com> | |
| 15 | --- | |
| 16 | arch/x86/kvm/vmx.c | 15 +++++++++++++-- | |
| 17 | 1 file changed, 13 insertions(+), 2 deletions(-) | |
| 18 | ||
| 19 | diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c | |
| e2af2a61 | 20 | index 1a5617fc8b6a..5c8bd2d61080 100644 |
| 2dc5b5fe TL |
21 | --- a/arch/x86/kvm/vmx.c |
| 22 | +++ b/arch/x86/kvm/vmx.c | |
| e2af2a61 | 23 | @@ -7575,6 +7575,12 @@ static int handle_vmon(struct kvm_vcpu *vcpu) |
| 2dc5b5fe TL |
24 | return 1; |
| 25 | } | |
| 26 | ||
| 27 | + /* CPL=0 must be checked manually. */ | |
| 28 | + if (vmx_get_cpl(vcpu)) { | |
| 29 | + kvm_queue_exception(vcpu, UD_VECTOR); | |
| 30 | + return 1; | |
| 31 | + } | |
| 32 | + | |
| 33 | if (vmx->nested.vmxon) { | |
| 34 | nested_vmx_failValid(vcpu, VMXERR_VMXON_IN_VMX_ROOT_OPERATION); | |
| 35 | return kvm_skip_emulated_instruction(vcpu); | |
| e2af2a61 | 36 | @@ -7634,6 +7640,11 @@ static int handle_vmon(struct kvm_vcpu *vcpu) |
| 2dc5b5fe TL |
37 | */ |
| 38 | static int nested_vmx_check_permission(struct kvm_vcpu *vcpu) | |
| 39 | { | |
| 40 | + if (vmx_get_cpl(vcpu)) { | |
| 41 | + kvm_queue_exception(vcpu, UD_VECTOR); | |
| 42 | + return 0; | |
| 43 | + } | |
| 44 | + | |
| 45 | if (!to_vmx(vcpu)->nested.vmxon) { | |
| 46 | kvm_queue_exception(vcpu, UD_VECTOR); | |
| 47 | return 0; | |
| e2af2a61 | 48 | @@ -7967,7 +7978,7 @@ static int handle_vmread(struct kvm_vcpu *vcpu) |
| 2dc5b5fe TL |
49 | if (get_vmx_mem_address(vcpu, exit_qualification, |
| 50 | vmx_instruction_info, true, &gva)) | |
| 51 | return 1; | |
| 52 | - /* _system ok, as hardware has verified cpl=0 */ | |
| 53 | + /* _system ok, nested_vmx_check_permission has verified cpl=0 */ | |
| 54 | kvm_write_guest_virt_system(&vcpu->arch.emulate_ctxt, gva, | |
| 55 | &field_value, (is_long_mode(vcpu) ? 8 : 4), NULL); | |
| 56 | } | |
| e2af2a61 | 57 | @@ -8110,7 +8121,7 @@ static int handle_vmptrst(struct kvm_vcpu *vcpu) |
| 2dc5b5fe TL |
58 | if (get_vmx_mem_address(vcpu, exit_qualification, |
| 59 | vmx_instruction_info, true, &vmcs_gva)) | |
| 60 | return 1; | |
| 61 | - /* ok to use *_system, as hardware has verified cpl=0 */ | |
| 62 | + /* *_system ok, nested_vmx_check_permission has verified cpl=0 */ | |
| 63 | if (kvm_write_guest_virt_system(&vcpu->arch.emulate_ctxt, vmcs_gva, | |
| 64 | (void *)&to_vmx(vcpu)->nested.current_vmptr, | |
| 65 | sizeof(u64), &e)) { |