pve-kernel-lowlatency-qoup/patches/kernel/0011-x86-KVM-Clean-up-host-s-steal-time-structure.patch
Thomas Lamprecht 6ad155377d rebase patches on top of Ubuntu-5.3.0-40.32
(generated with debian/scripts/import-upstream-tag)

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
2020-02-05 11:47:41 +01:00

83 lines
2.7 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Date: Fri, 31 Jan 2020 08:06:44 -0300
Subject: [PATCH] x86/KVM: Clean up host's steal time structure
CVE-2019-3016
CVE-2020-3016
Now that we are mapping kvm_steal_time from the guest directly we
don't need keep a copy of it in kvm_vcpu_arch.st. The same is true
for the stime field.
This is part of CVE-2019-3016.
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/include/asm/kvm_host.h | 3 +--
arch/x86/kvm/x86.c | 11 +++--------
2 files changed, 4 insertions(+), 10 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 7c06343614a4..f62f4ff5f4f4 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -674,10 +674,9 @@ struct kvm_vcpu_arch {
bool pvclock_set_guest_stopped_request;
struct {
+ u8 preempted;
u64 msr_val;
u64 last_steal;
- struct gfn_to_hva_cache stime;
- struct kvm_steal_time steal;
struct gfn_to_pfn_cache cache;
} st;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f63fa5846f08..6ce9ace8a801 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2509,7 +2509,7 @@ static void record_steal_time(struct kvm_vcpu *vcpu)
if (xchg(&st->preempted, 0) & KVM_VCPU_FLUSH_TLB)
kvm_vcpu_flush_tlb(vcpu, false);
- vcpu->arch.st.steal.preempted = 0;
+ vcpu->arch.st.preempted = 0;
if (st->version & 1)
st->version += 1; /* first time write, random junk */
@@ -2682,11 +2682,6 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
if (data & KVM_STEAL_RESERVED_MASK)
return 1;
- if (kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.st.stime,
- data & KVM_STEAL_VALID_BITS,
- sizeof(struct kvm_steal_time)))
- return 1;
-
vcpu->arch.st.msr_val = data;
if (!(data & KVM_MSR_ENABLED))
@@ -3404,7 +3399,7 @@ static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu)
if (!(vcpu->arch.st.msr_val & KVM_MSR_ENABLED))
return;
- if (vcpu->arch.st.steal.preempted)
+ if (vcpu->arch.st.preempted)
return;
if (kvm_map_gfn(vcpu, vcpu->arch.st.msr_val >> PAGE_SHIFT, &map,
@@ -3414,7 +3409,7 @@ static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu)
st = map.hva +
offset_in_page(vcpu->arch.st.msr_val & KVM_STEAL_VALID_BITS);
- st->preempted = vcpu->arch.st.steal.preempted = KVM_VCPU_PREEMPTED;
+ st->preempted = vcpu->arch.st.preempted = KVM_VCPU_PREEMPTED;
kvm_unmap_gfn(vcpu, &map, &vcpu->arch.st.cache, true, true);
}