From: Paolo Bonzini <pbonzini@redhat.com>
To: linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>, stable@vger.kernel.org
Subject: [FYI PATCH 2/5] x86/kvm: Introduce kvm_(un)map_gfn()
Date: Thu, 30 Jan 2020 19:01:53 +0100 [thread overview]
Message-ID: <1580407316-11391-3-git-send-email-pbonzini@redhat.com> (raw)
In-Reply-To: <1580407316-11391-1-git-send-email-pbonzini@redhat.com>
From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
kvm_vcpu_(un)map operates on gfns from any current address space.
In certain cases we want to make sure we are not mapping SMRAM
and for that we can use kvm_(un)map_gfn() that we are introducing
in this patch.
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>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
include/linux/kvm_host.h | 2 ++
virt/kvm/kvm_main.c | 29 ++++++++++++++++++++++++-----
2 files changed, 26 insertions(+), 5 deletions(-)
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 538c25e..0cb78f5 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -775,8 +775,10 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
kvm_pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn);
kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn);
int kvm_vcpu_map(struct kvm_vcpu *vcpu, gpa_t gpa, struct kvm_host_map *map);
+int kvm_map_gfn(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map);
struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn);
void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty);
+int kvm_unmap_gfn(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty);
unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu *vcpu, gfn_t gfn);
unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, bool *writable);
int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data, int offset,
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 0026829..9ef58a2 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1821,12 +1821,13 @@ struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
}
EXPORT_SYMBOL_GPL(gfn_to_page);
-static int __kvm_map_gfn(struct kvm_memory_slot *slot, gfn_t gfn,
+static int __kvm_map_gfn(struct kvm_memslots *slots, gfn_t gfn,
struct kvm_host_map *map)
{
kvm_pfn_t pfn;
void *hva = NULL;
struct page *page = KVM_UNMAPPED_PAGE;
+ struct kvm_memory_slot *slot = __gfn_to_memslot(slots, gfn);
if (!map)
return -EINVAL;
@@ -1855,14 +1856,20 @@ static int __kvm_map_gfn(struct kvm_memory_slot *slot, gfn_t gfn,
return 0;
}
+int kvm_map_gfn(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map)
+{
+ return __kvm_map_gfn(kvm_memslots(vcpu->kvm), gfn, map);
+}
+EXPORT_SYMBOL_GPL(kvm_map_gfn);
+
int kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map)
{
- return __kvm_map_gfn(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn, map);
+ return __kvm_map_gfn(kvm_vcpu_memslots(vcpu), gfn, map);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_map);
-void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map,
- bool dirty)
+static void __kvm_unmap_gfn(struct kvm_memory_slot *memslot,
+ struct kvm_host_map *map, bool dirty)
{
if (!map)
return;
@@ -1878,7 +1885,7 @@ void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map,
#endif
if (dirty) {
- kvm_vcpu_mark_page_dirty(vcpu, map->gfn);
+ mark_page_dirty_in_slot(memslot, map->gfn);
kvm_release_pfn_dirty(map->pfn);
} else {
kvm_release_pfn_clean(map->pfn);
@@ -1887,6 +1894,18 @@ void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map,
map->hva = NULL;
map->page = NULL;
}
+
+int kvm_unmap_gfn(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty)
+{
+ __kvm_unmap_gfn(gfn_to_memslot(vcpu->kvm, map->gfn), map, dirty);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(kvm_unmap_gfn);
+
+void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty)
+{
+ __kvm_unmap_gfn(kvm_vcpu_gfn_to_memslot(vcpu, map->gfn), map, dirty);
+}
EXPORT_SYMBOL_GPL(kvm_vcpu_unmap);
struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn)
--
1.8.3.1
next prev parent reply other threads:[~2020-01-30 18:02 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-30 18:01 [FYI PATCH 0/5] Missing TLB flushes Paolo Bonzini
2020-01-30 18:01 ` [FYI PATCH 1/5] x86/kvm: Be careful not to clear KVM_VCPU_FLUSH_TLB bit Paolo Bonzini
2020-01-30 18:01 ` Paolo Bonzini [this message]
2020-01-30 18:01 ` [FYI PATCH 3/5] x86/kvm: Cache gfn to pfn translation Paolo Bonzini
2020-01-30 18:01 ` [FYI PATCH 4/5] x86/KVM: Make sure KVM_VCPU_FLUSH_TLB flag is not missed Paolo Bonzini
2020-01-30 18:01 ` [FYI PATCH 5/5] x86/KVM: Clean up host's steal time structure Paolo Bonzini
2020-02-01 5:53 ` [FYI PATCH 0/5] Missing TLB flushes Wanpeng Li
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