linux-kernel - [PATCH v6 05/14] X86/nVMX: handle_vmptrld: Use kvm_vcpu_map when copying VMCS12 from guest memory

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1548966284-28642-6-git-send-email-karahmed@amazon.de>
Date:   Thu, 31 Jan 2019 21:24:35 +0100
From:   KarimAllah Ahmed <karahmed@...zon.de>
To:     x86@...nel.org, kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Radim Krčmář <rkrcmar@...hat.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Cc:     KarimAllah Ahmed <karahmed@...zon.de>
Subject: [PATCH v6 05/14] X86/nVMX: handle_vmptrld: Use kvm_vcpu_map when copying VMCS12 from guest memory

Use kvm_vcpu_map to the map the VMCS12 from guest memory because
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".

Signed-off-by: KarimAllah Ahmed <karahmed@...zon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
---
v4 -> v5:
- Switch to the new guest mapping API instead of reading directly from
  guest.
- unmap with dirty flag
v3 -> v4:
- Return VMXERR_VMPTRLD_INCORRECT_VMCS_REVISION_ID on failure (jmattson@)
v1 -> v2:
- Massage commit message a bit.
---
 arch/x86/kvm/vmx/nested.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 11b44a9..8fc327f 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -4521,11 +4521,10 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu)
 		return 1;
 
 	if (vmx->nested.current_vmptr != vmptr) {
+		struct kvm_host_map map;
 		struct vmcs12 *new_vmcs12;
-		struct page *page;
 
-		page = kvm_vcpu_gpa_to_page(vcpu, vmptr);
-		if (is_error_page(page)) {
+		if (kvm_vcpu_map(vcpu, gpa_to_gfn(vmptr), &map)) {
 			/*
 			 * Reads from an unbacked page return all 1s,
 			 * which means that the 32 bits located at the
@@ -4535,12 +4534,13 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu)
 			return nested_vmx_failValid(vcpu,
 				VMXERR_VMPTRLD_INCORRECT_VMCS_REVISION_ID);
 		}
-		new_vmcs12 = kmap(page);
+
+		new_vmcs12 = map.hva;
+
 		if (new_vmcs12->hdr.revision_id != VMCS12_REVISION ||
 		    (new_vmcs12->hdr.shadow_vmcs &&
 		     !nested_cpu_has_vmx_shadow_vmcs(vcpu))) {
-			kunmap(page);
-			kvm_release_page_clean(page);
+			kvm_vcpu_unmap(vcpu, &map, false);
 			return nested_vmx_failValid(vcpu,
 				VMXERR_VMPTRLD_INCORRECT_VMCS_REVISION_ID);
 		}
@@ -4552,8 +4552,7 @@ static int handle_vmptrld(struct kvm_vcpu *vcpu)
 		 * cached.
 		 */
 		memcpy(vmx->nested.cached_vmcs12, new_vmcs12, VMCS12_SIZE);
-		kunmap(page);
-		kvm_release_page_clean(page);
+		kvm_vcpu_unmap(vcpu, &map, false);
 
 		set_current_vmptr(vmx, vmptr);
 	}
-- 
2.7.4