udev: filter out non-sensically high onboard indexes reported by the …

…kernel

Let's not accept onboard interface indexes, that are so high that they are obviously non-sensical.

Fixes: #2407

src/udev/udev-builtin-net_id.c

@@ -106,6 +106,8 @@
#include "string-util.h"
#include "udev.h"

#define ONBOARD_INDEX_MAX (16*1024-1)

enum netname_type{
        NET_UNDEF,
        NET_PCI,
@@ -152,6 +154,13 @@ static int dev_pci_onboard(struct udev_device *dev, struct netnames *names) {
        if (idx <= 0)
                return -EINVAL;

        /* Some BIOSes report rubbish indexes that are excessively high (2^24-1 is an index VMware likes to report for
         * example). Let's define a cut-off where we don't consider the index reliable anymore. We pick some arbitrary
         * cut-off, which is somewhere beyond the realistic number of physical network interface a system might
         * have. Ideally the kernel would already filter his crap for us, but it doesn't currently. */
        if (idx > ONBOARD_INDEX_MAX)
                return -ENOENT;

        /* kernel provided port index for multiple ports on a single PCI function */
        attr = udev_device_get_sysattr_value(dev, "dev_port");
        if (attr)