KVM: PPC: fix information leak to userland

Structure kvm_ppc_pvinfo is copied to userland with flags and
pad fields unitialized.  It leads to leaking of contents of
kernel stack memory.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 2f87a1627f6c..38f756f25053 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -617,6 +617,7 @@ long kvm_arch_vm_ioctl(struct file *filp,
         switch (ioctl) {
         case KVM_PPC_GET_PVINFO: {
                 struct kvm_ppc_pvinfo pvinfo;
+                memset(&pvinfo, 0, sizeof(pvinfo));
                 r = kvm_vm_ioctl_get_pvinfo(&pvinfo);
                 if (copy_to_user(argp, &pvinfo, sizeof(pvinfo))) {
                         r = -EFAULT;