What do you think of ‘g_assert_not_reached();’. For example:
else {
g_assert_not_reached();
}
Thanks,
Li Qiang
发件人: Cornelia Huck
发送时间: 2019年1月4日 22:10
收件人: Li Qiang
抄送: wall...@linux.ibm.com; r...@twiddle.net; da...@redhat.com;
pa...@linux.ibm.com; borntrae...@de.ibm.com; qemu-s3...@nongnu.org;
qemu-devel@nongnu.org; peter.mayd...@linaro.org
主题: Re: [PATCH v2] s390: avoid potential null dereference
ins390_pcihost_unplug()
On Thu, 3 Jan 2019 07:16:12 -0800
Li Qiang <liq...@163.com> wrote:
> When getting the 'pbdev', the if...else has no default branch.
> From Coverity, the 'pbdev' maybe null when the 'dev' is not
> the TYPE_PCI_BRIDGE/TYPE_PCI_DEVICE/TYPE_S390_PCI_DEVICE.
> This patch adds a default branch for device plug and unplug.
>
> Spotted by Coverity: CID 1398593
>
> Signed-off-by: Li Qiang <liq...@163.com>
> ---
> Adds a default branch for device plug per Cornelia's review.
>
> hw/s390x/s390-pci-bus.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
> index 15759b6514..fe48a36ff6 100644
> --- a/hw/s390x/s390-pci-bus.c
> +++ b/hw/s390x/s390-pci-bus.c
> @@ -912,6 +912,9 @@ static void s390_pcihost_plug(HotplugHandler
> *hotplug_dev, DeviceState *dev,
> pbdev->fh = pbdev->idx;
> QTAILQ_INSERT_TAIL(&s->zpci_devs, pbdev, link);
> g_hash_table_insert(s->zpci_table, &pbdev->idx, pbdev);
> + } else {
> + error_setg(errp, "s390: device plug request for not supported device"
> + " type: %s", object_get_typename(OBJECT(dev)));
Maybe make this "s390/pci: plugging device type <%s> is not supported"?
> }
> }
>
> @@ -956,6 +959,10 @@ static void s390_pcihost_unplug(HotplugHandler
> *hotplug_dev, DeviceState *dev,
> } else if (object_dynamic_cast(OBJECT(dev), TYPE_S390_PCI_DEVICE)) {
> pbdev = S390_PCI_DEVICE(dev);
> pci_dev = pbdev->pdev;
> + } else {
> + error_setg(errp, "s390: device unplug request for not supported
> device"
> + " type: %s", object_get_typename(OBJECT(dev)));
Halil has a point when he suggests an assert here. If we fence the
device type in the plug function, I can't think of a way we would end
up here.
> + return;
> }
>
> switch (pbdev->state) {
