kvm, cpuid: Fix sparse warning

We need to copy padding to kernel space first before looking at it.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
This commit is contained in:
Borislav Petkov 2013-11-06 15:46:02 +01:00 committed by Gleb Natapov
parent a890b6fefd
commit 1b2ca42267

View File

@ -564,6 +564,7 @@ static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
__u32 num_entries, unsigned int ioctl_type)
{
int i;
__u32 pad[3];
if (ioctl_type != KVM_GET_EMULATED_CPUID)
return false;
@ -577,9 +578,10 @@ static bool sanity_check_entries(struct kvm_cpuid_entry2 __user *entries,
* sheds a tear.
*/
for (i = 0; i < num_entries; i++) {
if (entries[i].padding[0] ||
entries[i].padding[1] ||
entries[i].padding[2])
if (copy_from_user(pad, entries[i].padding, sizeof(pad)))
return true;
if (pad[0] || pad[1] || pad[2])
return true;
}
return false;