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authorLinus Torvalds <torvalds@linux-foundation.org>2013-03-19 18:24:12 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-03-19 18:24:12 -0700
commitea4a0ce11160200410abbabd44ec9e75e93a95be (patch)
tree20ceced4ddc4b34d78ce1318d2bc5a58debf08aa /arch
parent10b38669d64c757cfd927e3820292c580ed70aae (diff)
parenta2c118bfab8bc6b8bb213abfc35201e441693d55 (diff)
downloadlinux-linaro-stable-ea4a0ce11160200410abbabd44ec9e75e93a95be.tar.gz
Merge git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Marcelo Tosatti. * git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: Fix bounds checking in ioapic indirect register reads (CVE-2013-1798) KVM: x86: Convert MSR_KVM_SYSTEM_TIME to use gfn_to_hva_cache functions (CVE-2013-1797) KVM: x86: fix for buffer overflow in handling of MSR_KVM_SYSTEM_TIME (CVE-2013-1796) KVM: x86: fix deadlock in clock-in-progress request handling KVM: allow host header to be included even for !CONFIG_KVM
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/include/asm/kvm_host.h4
-rw-r--r--arch/x86/kvm/x86.c64
2 files changed, 33 insertions, 35 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 635a74d22409..4979778cc7fb 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -414,8 +414,8 @@ struct kvm_vcpu_arch {
gpa_t time;
struct pvclock_vcpu_time_info hv_clock;
unsigned int hw_tsc_khz;
- unsigned int time_offset;
- struct page *time_page;
+ struct gfn_to_hva_cache pv_time;
+ bool pv_time_enabled;
/* set guest stopped flag in pvclock flags field */
bool pvclock_set_guest_stopped_request;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f71500af1f81..f19ac0aca60d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1406,25 +1406,15 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
unsigned long flags, this_tsc_khz;
struct kvm_vcpu_arch *vcpu = &v->arch;
struct kvm_arch *ka = &v->kvm->arch;
- void *shared_kaddr;
s64 kernel_ns, max_kernel_ns;
u64 tsc_timestamp, host_tsc;
- struct pvclock_vcpu_time_info *guest_hv_clock;
+ struct pvclock_vcpu_time_info guest_hv_clock;
u8 pvclock_flags;
bool use_master_clock;
kernel_ns = 0;
host_tsc = 0;
- /* Keep irq disabled to prevent changes to the clock */
- local_irq_save(flags);
- this_tsc_khz = __get_cpu_var(cpu_tsc_khz);
- if (unlikely(this_tsc_khz == 0)) {
- local_irq_restore(flags);
- kvm_make_request(KVM_REQ_CLOCK_UPDATE, v);
- return 1;
- }
-
/*
* If the host uses TSC clock, then passthrough TSC as stable
* to the guest.
@@ -1436,6 +1426,15 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
kernel_ns = ka->master_kernel_ns;
}
spin_unlock(&ka->pvclock_gtod_sync_lock);
+
+ /* Keep irq disabled to prevent changes to the clock */
+ local_irq_save(flags);
+ this_tsc_khz = __get_cpu_var(cpu_tsc_khz);
+ if (unlikely(this_tsc_khz == 0)) {
+ local_irq_restore(flags);
+ kvm_make_request(KVM_REQ_CLOCK_UPDATE, v);
+ return 1;
+ }
if (!use_master_clock) {
host_tsc = native_read_tsc();
kernel_ns = get_kernel_ns();
@@ -1463,7 +1462,7 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
local_irq_restore(flags);
- if (!vcpu->time_page)
+ if (!vcpu->pv_time_enabled)
return 0;
/*
@@ -1525,12 +1524,12 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
*/
vcpu->hv_clock.version += 2;
- shared_kaddr = kmap_atomic(vcpu->time_page);
-
- guest_hv_clock = shared_kaddr + vcpu->time_offset;
+ if (unlikely(kvm_read_guest_cached(v->kvm, &vcpu->pv_time,
+ &guest_hv_clock, sizeof(guest_hv_clock))))
+ return 0;
/* retain PVCLOCK_GUEST_STOPPED if set in guest copy */
- pvclock_flags = (guest_hv_clock->flags & PVCLOCK_GUEST_STOPPED);
+ pvclock_flags = (guest_hv_clock.flags & PVCLOCK_GUEST_STOPPED);
if (vcpu->pvclock_set_guest_stopped_request) {
pvclock_flags |= PVCLOCK_GUEST_STOPPED;
@@ -1543,12 +1542,9 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
vcpu->hv_clock.flags = pvclock_flags;
- memcpy(shared_kaddr + vcpu->time_offset, &vcpu->hv_clock,
- sizeof(vcpu->hv_clock));
-
- kunmap_atomic(shared_kaddr);
-
- mark_page_dirty(v->kvm, vcpu->time >> PAGE_SHIFT);
+ kvm_write_guest_cached(v->kvm, &vcpu->pv_time,
+ &vcpu->hv_clock,
+ sizeof(vcpu->hv_clock));
return 0;
}
@@ -1837,10 +1833,7 @@ static int kvm_pv_enable_async_pf(struct kvm_vcpu *vcpu, u64 data)
static void kvmclock_reset(struct kvm_vcpu *vcpu)
{
- if (vcpu->arch.time_page) {
- kvm_release_page_dirty(vcpu->arch.time_page);
- vcpu->arch.time_page = NULL;
- }
+ vcpu->arch.pv_time_enabled = false;
}
static void accumulate_steal_time(struct kvm_vcpu *vcpu)
@@ -1947,6 +1940,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
break;
case MSR_KVM_SYSTEM_TIME_NEW:
case MSR_KVM_SYSTEM_TIME: {
+ u64 gpa_offset;
kvmclock_reset(vcpu);
vcpu->arch.time = data;
@@ -1956,14 +1950,17 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
if (!(data & 1))
break;
- /* ...but clean it before doing the actual write */
- vcpu->arch.time_offset = data & ~(PAGE_MASK | 1);
+ gpa_offset = data & ~(PAGE_MASK | 1);
- vcpu->arch.time_page =
- gfn_to_page(vcpu->kvm, data >> PAGE_SHIFT);
+ /* Check that the address is 32-byte aligned. */
+ if (gpa_offset & (sizeof(struct pvclock_vcpu_time_info) - 1))
+ break;
- if (is_error_page(vcpu->arch.time_page))
- vcpu->arch.time_page = NULL;
+ if (kvm_gfn_to_hva_cache_init(vcpu->kvm,
+ &vcpu->arch.pv_time, data & ~1ULL))
+ vcpu->arch.pv_time_enabled = false;
+ else
+ vcpu->arch.pv_time_enabled = true;
break;
}
@@ -2967,7 +2964,7 @@ static int kvm_vcpu_ioctl_x86_set_xcrs(struct kvm_vcpu *vcpu,
*/
static int kvm_set_guest_paused(struct kvm_vcpu *vcpu)
{
- if (!vcpu->arch.time_page)
+ if (!vcpu->arch.pv_time_enabled)
return -EINVAL;
vcpu->arch.pvclock_set_guest_stopped_request = true;
kvm_make_request(KVM_REQ_CLOCK_UPDATE, vcpu);
@@ -6718,6 +6715,7 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
goto fail_free_wbinvd_dirty_mask;
vcpu->arch.ia32_tsc_adjust_msr = 0x0;
+ vcpu->arch.pv_time_enabled = false;
kvm_async_pf_hash_reset(vcpu);
kvm_pmu_init(vcpu);