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-rw-r--r--arch/x86/include/asm/kvm_host.h3
-rw-r--r--arch/x86/kvm/svm/avic.c9
-rw-r--r--arch/x86/kvm/vmx/vmx.c88
-rw-r--r--arch/x86/kvm/x86.c37
4 files changed, 81 insertions, 56 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 5bb0a2bbd9c4..69e94aa716e9 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1696,7 +1696,8 @@ void __kvm_request_immediate_exit(struct kvm_vcpu *vcpu);
int kvm_is_in_guest(void);
-int __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, u32 size);
+void __user *__x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa,
+ u32 size);
bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu);
bool kvm_vcpu_is_bsp(struct kvm_vcpu *vcpu);
diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 8c550999ace0..0ef84d57b72e 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -233,7 +233,8 @@ static u64 *avic_get_physical_id_entry(struct kvm_vcpu *vcpu,
*/
static int avic_update_access_page(struct kvm *kvm, bool activate)
{
- int ret = 0;
+ void __user *ret;
+ int r = 0;
mutex_lock(&kvm->slots_lock);
/*
@@ -249,13 +250,15 @@ static int avic_update_access_page(struct kvm *kvm, bool activate)
APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
APIC_DEFAULT_PHYS_BASE,
activate ? PAGE_SIZE : 0);
- if (ret)
+ if (IS_ERR(ret)) {
+ r = PTR_ERR(ret);
goto out;
+ }
kvm->arch.apic_access_page_done = activate;
out:
mutex_unlock(&kvm->slots_lock);
- return ret;
+ return r;
}
static int avic_init_backing_page(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index fd70bdf63844..46b32aa43811 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -3515,42 +3515,33 @@ bool __vmx_guest_state_valid(struct kvm_vcpu *vcpu)
return true;
}
-static int init_rmode_tss(struct kvm *kvm)
+static int init_rmode_tss(struct kvm *kvm, void __user *ua)
{
- gfn_t fn;
- u16 data = 0;
- int idx, r;
+ const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
+ u16 data;
+ int i;
+
+ for (i = 0; i < 3; i++) {
+ if (__copy_to_user(ua + PAGE_SIZE * i, zero_page, PAGE_SIZE))
+ return -EFAULT;
+ }
- idx = srcu_read_lock(&kvm->srcu);
- fn = to_kvm_vmx(kvm)->tss_addr >> PAGE_SHIFT;
- r = kvm_clear_guest_page(kvm, fn, 0, PAGE_SIZE);
- if (r < 0)
- goto out;
data = TSS_BASE_SIZE + TSS_REDIRECTION_SIZE;
- r = kvm_write_guest_page(kvm, fn++, &data,
- TSS_IOPB_BASE_OFFSET, sizeof(u16));
- if (r < 0)
- goto out;
- r = kvm_clear_guest_page(kvm, fn++, 0, PAGE_SIZE);
- if (r < 0)
- goto out;
- r = kvm_clear_guest_page(kvm, fn, 0, PAGE_SIZE);
- if (r < 0)
- goto out;
+ if (__copy_to_user(ua + TSS_IOPB_BASE_OFFSET, &data, sizeof(u16)))
+ return -EFAULT;
+
data = ~0;
- r = kvm_write_guest_page(kvm, fn, &data,
- RMODE_TSS_SIZE - 2 * PAGE_SIZE - 1,
- sizeof(u8));
-out:
- srcu_read_unlock(&kvm->srcu, idx);
- return r;
+ if (__copy_to_user(ua + RMODE_TSS_SIZE - 1, &data, sizeof(u8)))
+ return -EFAULT;
+
+ return 0;
}
static int init_rmode_identity_map(struct kvm *kvm)
{
struct kvm_vmx *kvm_vmx = to_kvm_vmx(kvm);
int i, r = 0;
- kvm_pfn_t identity_map_pfn;
+ void __user *uaddr;
u32 tmp;
/* Protect kvm_vmx->ept_identity_pagetable_done. */
@@ -3561,24 +3552,24 @@ static int init_rmode_identity_map(struct kvm *kvm)
if (!kvm_vmx->ept_identity_map_addr)
kvm_vmx->ept_identity_map_addr = VMX_EPT_IDENTITY_PAGETABLE_ADDR;
- identity_map_pfn = kvm_vmx->ept_identity_map_addr >> PAGE_SHIFT;
- r = __x86_set_memory_region(kvm, IDENTITY_PAGETABLE_PRIVATE_MEMSLOT,
- kvm_vmx->ept_identity_map_addr, PAGE_SIZE);
- if (r < 0)
+ uaddr = __x86_set_memory_region(kvm,
+ IDENTITY_PAGETABLE_PRIVATE_MEMSLOT,
+ kvm_vmx->ept_identity_map_addr,
+ PAGE_SIZE);
+ if (IS_ERR(uaddr)) {
+ r = PTR_ERR(uaddr);
goto out;
+ }
- r = kvm_clear_guest_page(kvm, identity_map_pfn, 0, PAGE_SIZE);
- if (r < 0)
- goto out;
/* Set up identity-mapping pagetable for EPT in real mode */
for (i = 0; i < PT32_ENT_PER_PAGE; i++) {
tmp = (i << 22) + (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER |
_PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_PSE);
- r = kvm_write_guest_page(kvm, identity_map_pfn,
- &tmp, i * sizeof(tmp), sizeof(tmp));
- if (r < 0)
+ if (__copy_to_user(uaddr + i * sizeof(tmp), &tmp, sizeof(tmp))) {
+ r = -EFAULT;
goto out;
+ }
}
kvm_vmx->ept_identity_pagetable_done = true;
@@ -3605,19 +3596,22 @@ static void seg_setup(int seg)
static int alloc_apic_access_page(struct kvm *kvm)
{
struct page *page;
- int r = 0;
+ void __user *hva;
+ int ret = 0;
mutex_lock(&kvm->slots_lock);
if (kvm->arch.apic_access_page_done)
goto out;
- r = __x86_set_memory_region(kvm, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
- APIC_DEFAULT_PHYS_BASE, PAGE_SIZE);
- if (r)
+ hva = __x86_set_memory_region(kvm, APIC_ACCESS_PAGE_PRIVATE_MEMSLOT,
+ APIC_DEFAULT_PHYS_BASE, PAGE_SIZE);
+ if (IS_ERR(hva)) {
+ ret = PTR_ERR(hva);
goto out;
+ }
page = gfn_to_page(kvm, APIC_DEFAULT_PHYS_BASE >> PAGE_SHIFT);
if (is_error_page(page)) {
- r = -EFAULT;
+ ret = -EFAULT;
goto out;
}
@@ -3629,7 +3623,7 @@ static int alloc_apic_access_page(struct kvm *kvm)
kvm->arch.apic_access_page_done = true;
out:
mutex_unlock(&kvm->slots_lock);
- return r;
+ return ret;
}
int allocate_vpid(void)
@@ -4638,7 +4632,7 @@ static int vmx_interrupt_allowed(struct kvm_vcpu *vcpu, bool for_injection)
static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr)
{
- int ret;
+ void __user *ret;
if (enable_unrestricted_guest)
return 0;
@@ -4648,10 +4642,12 @@ static int vmx_set_tss_addr(struct kvm *kvm, unsigned int addr)
PAGE_SIZE * 3);
mutex_unlock(&kvm->slots_lock);
- if (ret)
- return ret;
+ if (IS_ERR(ret))
+ return PTR_ERR(ret);
+
to_kvm_vmx(kvm)->tss_addr = addr;
- return init_rmode_tss(kvm);
+
+ return init_rmode_tss(kvm, ret);
}
static int vmx_set_identity_map_addr(struct kvm *kvm, u64 ident_addr)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 773cb52cb775..b4ac726526f8 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10354,7 +10354,32 @@ void kvm_arch_sync_events(struct kvm *kvm)
kvm_free_pit(kvm);
}
-int __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, u32 size)
+#define ERR_PTR_USR(e) ((void __user *)ERR_PTR(e))
+
+/**
+ * __x86_set_memory_region: Setup KVM internal memory slot
+ *
+ * @kvm: the kvm pointer to the VM.
+ * @id: the slot ID to setup.
+ * @gpa: the GPA to install the slot (unused when @size == 0).
+ * @size: the size of the slot. Set to zero to uninstall a slot.
+ *
+ * This function helps to setup a KVM internal memory slot. Specify
+ * @size > 0 to install a new slot, while @size == 0 to uninstall a
+ * slot. The return code can be one of the following:
+ *
+ * HVA: on success (uninstall will return a bogus HVA)
+ * -errno: on error
+ *
+ * The caller should always use IS_ERR() to check the return value
+ * before use. Note, the KVM internal memory slots are guaranteed to
+ * remain valid and unchanged until the VM is destroyed, i.e., the
+ * GPA->HVA translation will not change. However, the HVA is a user
+ * address, i.e. its accessibility is not guaranteed, and must be
+ * accessed via __copy_{to,from}_user().
+ */
+void __user * __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa,
+ u32 size)
{
int i, r;
unsigned long hva, old_npages;
@@ -10363,12 +10388,12 @@ int __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, u32 size)
/* Called with kvm->slots_lock held. */
if (WARN_ON(id >= KVM_MEM_SLOTS_NUM))
- return -EINVAL;
+ return ERR_PTR_USR(-EINVAL);
slot = id_to_memslot(slots, id);
if (size) {
if (slot && slot->npages)
- return -EEXIST;
+ return ERR_PTR_USR(-EEXIST);
/*
* MAP_SHARED to prevent internal slot pages from being moved
@@ -10377,7 +10402,7 @@ int __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, u32 size)
hva = vm_mmap(NULL, 0, size, PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_ANONYMOUS, 0);
if (IS_ERR((void *)hva))
- return PTR_ERR((void *)hva);
+ return (void __user *)hva;
} else {
if (!slot || !slot->npages)
return 0;
@@ -10396,13 +10421,13 @@ int __x86_set_memory_region(struct kvm *kvm, int id, gpa_t gpa, u32 size)
m.memory_size = size;
r = __kvm_set_memory_region(kvm, &m);
if (r < 0)
- return r;
+ return ERR_PTR_USR(r);
}
if (!size)
vm_munmap(hva, old_npages * PAGE_SIZE);
- return 0;
+ return (void __user *)hva;
}
EXPORT_SYMBOL_GPL(__x86_set_memory_region);