Browse Source

KVM: make checks stricter in coalesced_mmio_in_range()

My testing version of Smatch complains that addr and len come from
the user and they can wrap.  The path is:
  -> kvm_vm_ioctl()
     -> kvm_vm_ioctl_unregister_coalesced_mmio()
        -> coalesced_mmio_in_range()

I don't know what the implications are of wrapping here, but we may
as well fix it, if only to silence the warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
master
Dan Carpenter 10 years ago
committed by Avi Kivity
parent
commit
1a214246cb
  1. 12
      virt/kvm/coalesced_mmio.c

12
virt/kvm/coalesced_mmio.c

@ -28,9 +28,15 @@ static int coalesced_mmio_in_range(struct kvm_coalesced_mmio_dev *dev,
* (addr,len) is fully included in
* (zone->addr, zone->size)
*/
return (dev->zone.addr <= addr &&
addr + len <= dev->zone.addr + dev->zone.size);
if (len < 0)
return 0;
if (addr + len < addr)
return 0;
if (addr < dev->zone.addr)
return 0;
if (addr + len > dev->zone.addr + dev->zone.size)
return 0;
return 1;
}
static int coalesced_mmio_has_room(struct kvm_coalesced_mmio_dev *dev)

Loading…
Cancel
Save