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| author | Avi Kivity <avi@redhat.com> | 2010-07-26 18:32:38 +0300 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2010-08-02 08:10:18 +0300 |
| commit | 3444d7da1839b851eefedd372978d8a982316c36 (patch) | |
| tree | b9fef27fbe36b455dc242670fa0f4025a2df1dc2 /arch | |
| parent | 9a3aad70572c3f4d55e7f09ac4eb313d41d0a484 (diff) | |
| download | linux-3.10-3444d7da1839b851eefedd372978d8a982316c36.tar.gz linux-3.10-3444d7da1839b851eefedd372978d8a982316c36.tar.bz2 linux-3.10-3444d7da1839b851eefedd372978d8a982316c36.zip | |
KVM: VMX: Fix host GDT.LIMIT corruption
vmx does not restore GDT.LIMIT to the host value, instead it sets it to 64KB.
This means host userspace can learn a few bits of host memory.
Fix by reloading GDTR when we load other host state.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/vmx.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 2fdcc9819f3..27a0222c294 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -185,6 +185,7 @@ static void kvm_cpu_vmxoff(void); static DEFINE_PER_CPU(struct vmcs *, vmxarea); static DEFINE_PER_CPU(struct vmcs *, current_vmcs); static DEFINE_PER_CPU(struct list_head, vcpus_on_cpu); +static DEFINE_PER_CPU(struct desc_ptr, host_gdt); static unsigned long *vmx_io_bitmap_a; static unsigned long *vmx_io_bitmap_b; @@ -871,6 +872,7 @@ static void __vmx_load_host_state(struct vcpu_vmx *vmx) #endif if (current_thread_info()->status & TS_USEDFPU) clts(); + load_gdt(&__get_cpu_var(host_gdt)); } static void vmx_load_host_state(struct vcpu_vmx *vmx) @@ -1379,6 +1381,8 @@ static int hardware_enable(void *garbage) ept_sync_global(); } + store_gdt(&__get_cpu_var(host_gdt)); + return 0; } |