From: Paolo Bonzini <pbonzini@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Sean Christopherson <seanjc@google.com>, Kai Huang <kai.huang@intel.com>
Subject: [PATCH 16/17] KVM: x86/mmu: Initialize kvm_page_fault's pfn and hva to error values
Date: Tue, 7 May 2024 11:58:16 -0400 [thread overview]
Message-ID: <20240507155817.3951344-17-pbonzini@redhat.com> (raw)
In-Reply-To: <20240507155817.3951344-1-pbonzini@redhat.com>
From: Sean Christopherson <seanjc@google.com>
Explicitly set "pfn" and "hva" to error values in kvm_mmu_do_page_fault()
to harden KVM against using "uninitialized" values. In quotes because the
fields are actually zero-initialized, and zero is a legal value for both
page frame numbers and virtual addresses. E.g. failure to set "pfn" prior
to creating an SPTE could result in KVM pointing at physical address '0',
which is far less desirable than KVM generating a SPTE with reserved PA
bits set and thus effectively killing the VM.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Message-ID: <20240228024147.41573-16-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/mmu/mmu_internal.h | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/x86/kvm/mmu/mmu_internal.h b/arch/x86/kvm/mmu/mmu_internal.h
index dfd9ff383663..ce2fcd19ba6b 100644
--- a/arch/x86/kvm/mmu/mmu_internal.h
+++ b/arch/x86/kvm/mmu/mmu_internal.h
@@ -307,6 +307,9 @@ static inline int kvm_mmu_do_page_fault(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
.req_level = PG_LEVEL_4K,
.goal_level = PG_LEVEL_4K,
.is_private = err & PFERR_PRIVATE_ACCESS,
+
+ .pfn = KVM_PFN_ERR_FAULT,
+ .hva = KVM_HVA_ERR_BAD,
};
int r;
--
2.43.0
next prev parent reply other threads:[~2024-05-07 15:58 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-07 15:58 [PATCH v2 00/17] KVM: x86/mmu: Page fault and MMIO cleanups Paolo Bonzini
2024-05-07 15:58 ` [PATCH 01/17] KVM: x86/mmu: Exit to userspace with -EFAULT if private fault hits emulation Paolo Bonzini
2024-05-13 5:25 ` Xiaoyao Li
2024-05-07 15:58 ` [PATCH 02/17] KVM: x86: Remove separate "bit" defines for page fault error code masks Paolo Bonzini
2024-05-13 5:29 ` Xiaoyao Li
2024-05-07 15:58 ` [PATCH 03/17] KVM: x86: Define more SEV+ page fault error bits/flags for #NPF Paolo Bonzini
2024-05-07 15:58 ` [PATCH 04/17] KVM: x86: Move synthetic PFERR_* sanity checks to SVM's #NPF handler Paolo Bonzini
2024-05-13 5:50 ` Xiaoyao Li
2024-05-13 17:31 ` Sean Christopherson
2024-05-14 4:25 ` Xiaoyao Li
2024-05-14 15:32 ` Sean Christopherson
2024-05-15 1:03 ` Xiaoyao Li
2024-05-07 15:58 ` [PATCH 05/17] KVM: x86/mmu: Pass full 64-bit error code when handling page faults Paolo Bonzini
2024-05-07 15:58 ` [PATCH 06/17] KVM: x86/mmu: WARN if upper 32 bits of legacy #PF error code are non-zero Paolo Bonzini
2024-05-07 15:58 ` [PATCH 07/17] KVM: x86/mmu: Use synthetic page fault error code to indicate private faults Paolo Bonzini
2024-05-13 5:56 ` Xiaoyao Li
2024-05-07 15:58 ` [PATCH 08/17] KVM: x86/mmu: check for invalid async page faults involving private memory Paolo Bonzini
2024-05-07 15:58 ` [PATCH 09/17] KVM: x86/mmu: WARN and skip MMIO cache on private, reserved page faults Paolo Bonzini
2024-05-13 6:15 ` Xiaoyao Li
2024-05-07 15:58 ` [PATCH 10/17] KVM: x86/mmu: Move private vs. shared check above slot validity checks Paolo Bonzini
2024-05-13 6:22 ` Xiaoyao Li
2024-05-07 15:58 ` [PATCH 11/17] KVM: x86/mmu: Don't force emulation of L2 accesses to non-APIC internal slots Paolo Bonzini
2024-05-07 15:58 ` [PATCH 12/17] KVM: x86/mmu: Explicitly disallow private accesses to emulated MMIO Paolo Bonzini
2024-05-13 6:26 ` Xiaoyao Li
2024-05-07 15:58 ` [PATCH 13/17] KVM: x86/mmu: Move slot checks from __kvm_faultin_pfn() to kvm_faultin_pfn() Paolo Bonzini
2024-05-13 6:27 ` Xiaoyao Li
2024-05-07 15:58 ` [PATCH 14/17] KVM: x86/mmu: Handle no-slot faults at the beginning of kvm_faultin_pfn() Paolo Bonzini
2024-05-13 6:28 ` Xiaoyao Li
2024-05-07 15:58 ` [PATCH 15/17] KVM: x86/mmu: Set kvm_page_fault.hva to KVM_HVA_ERR_BAD for "no slot" faults Paolo Bonzini
2024-05-13 6:28 ` Xiaoyao Li
2024-05-07 15:58 ` Paolo Bonzini [this message]
2024-05-13 6:29 ` [PATCH 16/17] KVM: x86/mmu: Initialize kvm_page_fault's pfn and hva to error values Xiaoyao Li
2024-05-07 15:58 ` [PATCH 17/17] KVM: x86/mmu: Sanity check that __kvm_faultin_pfn() doesn't create noslot pfns Paolo Bonzini
2024-05-13 6:40 ` Xiaoyao Li
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