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@xxxxxxxxxx> diff --git a/virt/kvm/coalesced_mmio.c b/virt/kvm/coalesced_mmio.c index a6ec206..88b2fe3 100644 --- a/virt/kvm/coalesced_mmio.c +++ b/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) -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html