Hi Alex, On 2/5/2024 2:35 PM, Alex Williamson wrote: > On Thu, 1 Feb 2024 20:57:09 -0800 > Reinette Chatre <reinette.chatre@xxxxxxxxx> wrote: ... >> @@ -715,13 +724,13 @@ static int vfio_pci_set_intx_trigger(struct vfio_pci_core_device *vdev, >> if (is_intx(vdev)) >> return vfio_irq_set_block(vdev, start, count, fds, index); >> >> - ret = vfio_intx_enable(vdev); >> + ret = vfio_intx_enable(vdev, start, count, index); > > Please trace what happens when a user calls SET_IRQS to setup a trigger > eventfd with start = 0, count = 1, followed by any other combination of > start and count values once is_intx() is true. vfio_intx_enable() > cannot be the only place we bounds check the user, all of the INTx > callbacks should be an error or nop if vector != 0. Thanks, > Thank you very much for catching this. I plan to add the vector check to the device_name() and request_interrupt() callbacks. I do not think it is necessary to add the vector check to disable() since it does not operate on a range and from what I can tell it depends on a successful enable() that already contains the vector check. Similar, free_interrupt() requires a successful request_interrupt() (that will have vector check in next version). send_eventfd() requires a valid interrupt context that is only possible if enable() or request_interrupt() succeeded. If user space creates an eventfd with start = 0 and count = 1 and then attempts to trigger the eventfd using another combination then the changes in this series will result in a nop while the current implementation will result in -EINVAL. Is this acceptable? Reinette
