linux-kernel - [PATCH v3] KVM: x86: Fix the intel_pt PMI handling wrongly considered from guest

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-next>] [day] [month] [year] [list]

Message-Id: <20220523140821.1345605-1-yanfei.xu@intel.com>
Date:   Mon, 23 May 2022 22:08:21 +0800
From:   Yanfei Xu <yanfei.xu@...el.com>
To:     pbonzini@...hat.com, seanjc@...gle.com, vkuznets@...hat.com,
        wanpengli@...cent.com, jmattson@...gle.com, joro@...tes.org,
        tglx@...utronix.de, mingo@...hat.com, bp@...en8.de,
        dave.hansen@...ux.intel.com, wei.w.wang@...el.com,
        kan.liang@...el.com
Cc:     x86@...nel.org, kvm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH v3] KVM: x86: Fix the intel_pt PMI handling wrongly considered from guest

When kernel handles the vm-exit caused by external interrupts and NMI,
it always set a type of kvm_intr_type to handling_intr_from_guest to
tell if it's dealing an IRQ or NMI. For the PMI scenario, it could be
IRQ or NMI.
However the intel_pt PMI certainly is a NMI PMI, hence using
kvm_handling_nmi_from_guest() to distinguish if the intel_pt PMI comes
from guest is more appropriate. This modification can avoid the host
wrongly considered the intel_pt PMI comes from a guest once the host
intel_pt PMI breaks the handling of vm-exit of external interrupts.

Fixes: db215756ae59 ("KVM: x86: More precisely identify NMI from guest when handling PMI")
Signed-off-by: Yanfei Xu <yanfei.xu@...el.com>
---
v1->v2:
1.Fix vmx_handle_intel_pt_intr() directly instead of changing the generic function.
2.Tune the commit message.

v2->v3:
Add the NULL pointer check of variable "vcpu".

 arch/x86/kvm/vmx/vmx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 610355b9ccce..982df9c000d3 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7856,7 +7856,7 @@ static unsigned int vmx_handle_intel_pt_intr(void)
 	struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
 
 	/* '0' on failure so that the !PT case can use a RET0 static call. */
-	if (!kvm_arch_pmi_in_guest(vcpu))
+	if (!vcpu || !kvm_handling_nmi_from_guest(vcpu))
 		return 0;
 
 	kvm_make_request(KVM_REQ_PMI, vcpu);
-- 
2.32.0