4.14-stable review patch. If anyone has any objections, please let me know.
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From: Sean Christopherson sean.j.christopherson@intel.com
[ Upstream commit 0a06d4256674c4e041945b52044941995fee237d ]
Do not expose the address of vmx->nested.current_vmptr to kvm_write_guest_virt_system() as the resulting __copy_to_user() call will trigger a WARN when CONFIG_HARDENED_USERCOPY is enabled.
Opportunistically clean up variable names in handle_vmptrst() to improve readability, e.g. vmcs_gva is misleading as the memory operand of VMPTRST is plain memory, not a VMCS.
Signed-off-by: Sean Christopherson sean.j.christopherson@intel.com Tested-by: Peter Shier pshier@google.com Reviewed-by: Peter Shier pshier@google.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kvm/vmx.c | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-)
--- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -8108,21 +8108,20 @@ static int handle_vmptrld(struct kvm_vcp /* Emulate the VMPTRST instruction */ static int handle_vmptrst(struct kvm_vcpu *vcpu) { - unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION); - u32 vmx_instruction_info = vmcs_read32(VMX_INSTRUCTION_INFO); - gva_t vmcs_gva; + unsigned long exit_qual = vmcs_readl(EXIT_QUALIFICATION); + u32 instr_info = vmcs_read32(VMX_INSTRUCTION_INFO); + gpa_t current_vmptr = to_vmx(vcpu)->nested.current_vmptr; struct x86_exception e; + gva_t gva;
if (!nested_vmx_check_permission(vcpu)) return 1;
- if (get_vmx_mem_address(vcpu, exit_qualification, - vmx_instruction_info, true, &vmcs_gva)) + if (get_vmx_mem_address(vcpu, exit_qual, instr_info, true, &gva)) return 1; /* *_system ok, nested_vmx_check_permission has verified cpl=0 */ - if (kvm_write_guest_virt_system(vcpu, vmcs_gva, - (void *)&to_vmx(vcpu)->nested.current_vmptr, - sizeof(u64), &e)) { + if (kvm_write_guest_virt_system(vcpu, gva, (void *)¤t_vmptr, + sizeof(gpa_t), &e)) { kvm_inject_page_fault(vcpu, &e); return 1; }