From: Miaohe Lin <linmiaohe@xxxxxxxxxx>
commit 23520b2def95205f132e167cf5b25c609975e959 upstream.
When pv_eoi_get_user() fails, 'val' may remain uninitialized and the return
value of pv_eoi_get_pending() becomes random. Fix the issue by initializing
the variable.
Reviewed-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kvm/lapic.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -637,9 +637,11 @@ static inline bool pv_eoi_enabled(struct
static bool pv_eoi_get_pending(struct kvm_vcpu *vcpu)
{
u8 val;
- if (pv_eoi_get_user(vcpu, &val) < 0)
+ if (pv_eoi_get_user(vcpu, &val) < 0) {
printk(KERN_WARNING "Can't read EOI MSR value: 0x%llx\n",
(unsigned long long)vcpu->arch.pv_eoi.msr_val);
+ return false;
+ }
return val & 0x1;
}
