static int dn_def_dev_strategy(ctl_table *table, int *name, int nlen,
void *oldval, size_t *oldlenp,
void *newval, size_t newlen,
void **context)
{
size_t len;
struct net_device *dev;
char devname[17];
size_t namel;
int rv = 0;
devname[0] = 0;
if (oldval && oldlenp) {
if (get_user(len, oldlenp))
return -EFAULT;
if (len) {
dev = dn_dev_get_default();
if (dev) {
strcpy(devname, dev->name);
dev_put(dev);
}
namel = strlen(devname) + 1;
if (len > namel) len = namel;
if (copy_to_user(oldval, devname, len))
return -EFAULT;
if (put_user(len, oldlenp))
return -EFAULT;
}
}
if (newval && newlen) {
if (newlen > 16)
return -E2BIG;
if (copy_from_user(devname, newval, newlen))
return -EFAULT;
devname[newlen] = 0;
dev = dev_get_by_name(devname);
if (dev == NULL)
return -ENODEV;
rv = -ENODEV;
if (dev->dn_ptr != NULL) {
rv = dn_dev_set_default(dev, 1);
if (rv)
dev_put(dev);
}
}
return rv;
}
static int dn_def_dev_handler(struct ctl_table *table, int write,
void __user *buffer,
size_t *lenp, loff_t *ppos)
{
size_t len;
struct net_device *dev;
char devname[17];
if (!*lenp || (*ppos && !write)) {
*lenp = 0;
return 0;
}
if (write) {
if (*lenp > 16)
return -E2BIG;
if (copy_from_user(devname, buffer, *lenp))
return -EFAULT;
devname[*lenp] = 0;
strip_it(devname);
dev = dev_get_by_name(&init_net, devname);
if (dev == NULL)
return -ENODEV;
if (dev->dn_ptr == NULL) {
dev_put(dev);
return -ENODEV;
}
if (dn_dev_set_default(dev, 1)) {
dev_put(dev);
return -ENODEV;
}
*ppos += *lenp;
return 0;
}
dev = dn_dev_get_default();
if (dev == NULL) {
*lenp = 0;
return 0;
}
strcpy(devname, dev->name);
dev_put(dev);
len = strlen(devname);
devname[len++] = '\n';
if (len > *lenp) len = *lenp;
if (copy_to_user(buffer, devname, len))
return -EFAULT;
*lenp = len;
*ppos += len;
return 0;
}