diff options
-rw-r--r-- | drivers/net/ppp/ppp_generic.c | 115 | ||||
-rw-r--r-- | include/uapi/linux/if_link.h | 8 |
2 files changed, 120 insertions, 3 deletions
diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index 59077c86ba0e..8dedafa1a95d 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -46,6 +46,7 @@ #include <linux/device.h> #include <linux/mutex.h> #include <linux/slab.h> +#include <linux/file.h> #include <asm/unaligned.h> #include <net/slhc_vj.h> #include <linux/atomic.h> @@ -186,6 +187,7 @@ struct channel { struct ppp_config { struct file *file; s32 unit; + bool ifname_is_set; }; /* @@ -286,6 +288,7 @@ static int unit_get(struct idr *p, void *ptr); static int unit_set(struct idr *p, void *ptr, int n); static void unit_put(struct idr *p, int n); static void *unit_find(struct idr *p, int n); +static void ppp_setup(struct net_device *dev); static const struct net_device_ops ppp_netdev_ops; @@ -964,7 +967,7 @@ static struct pernet_operations ppp_net_ops = { .size = sizeof(struct ppp_net), }; -static int ppp_unit_register(struct ppp *ppp, int unit) +static int ppp_unit_register(struct ppp *ppp, int unit, bool ifname_is_set) { struct ppp_net *pn = ppp_pernet(ppp->ppp_net); int ret; @@ -994,7 +997,8 @@ static int ppp_unit_register(struct ppp *ppp, int unit) } ppp->file.index = ret; - snprintf(ppp->dev->name, IFNAMSIZ, "ppp%i", ppp->file.index); + if (!ifname_is_set) + snprintf(ppp->dev->name, IFNAMSIZ, "ppp%i", ppp->file.index); ret = register_netdevice(ppp->dev); if (ret < 0) @@ -1043,7 +1047,7 @@ static int ppp_dev_configure(struct net *src_net, struct net_device *dev, ppp->active_filter = NULL; #endif /* CONFIG_PPP_FILTER */ - err = ppp_unit_register(ppp, conf->unit); + err = ppp_unit_register(ppp, conf->unit, conf->ifname_is_set); if (err < 0) return err; @@ -1052,6 +1056,99 @@ static int ppp_dev_configure(struct net *src_net, struct net_device *dev, return 0; } +static const struct nla_policy ppp_nl_policy[IFLA_PPP_MAX + 1] = { + [IFLA_PPP_DEV_FD] = { .type = NLA_S32 }, +}; + +static int ppp_nl_validate(struct nlattr *tb[], struct nlattr *data[]) +{ + if (!data) + return -EINVAL; + + if (!data[IFLA_PPP_DEV_FD]) + return -EINVAL; + if (nla_get_s32(data[IFLA_PPP_DEV_FD]) < 0) + return -EBADF; + + return 0; +} + +static int ppp_nl_newlink(struct net *src_net, struct net_device *dev, + struct nlattr *tb[], struct nlattr *data[]) +{ + struct ppp_config conf = { + .unit = -1, + .ifname_is_set = true, + }; + struct file *file; + int err; + + file = fget(nla_get_s32(data[IFLA_PPP_DEV_FD])); + if (!file) + return -EBADF; + + /* rtnl_lock is already held here, but ppp_create_interface() locks + * ppp_mutex before holding rtnl_lock. Using mutex_trylock() avoids + * possible deadlock due to lock order inversion, at the cost of + * pushing the problem back to userspace. + */ + if (!mutex_trylock(&ppp_mutex)) { + err = -EBUSY; + goto out; + } + + if (file->f_op != &ppp_device_fops || file->private_data) { + err = -EBADF; + goto out_unlock; + } + + conf.file = file; + err = ppp_dev_configure(src_net, dev, &conf); + +out_unlock: + mutex_unlock(&ppp_mutex); +out: + fput(file); + + return err; +} + +static void ppp_nl_dellink(struct net_device *dev, struct list_head *head) +{ + unregister_netdevice_queue(dev, head); +} + +static size_t ppp_nl_get_size(const struct net_device *dev) +{ + return 0; +} + +static int ppp_nl_fill_info(struct sk_buff *skb, const struct net_device *dev) +{ + return 0; +} + +static struct net *ppp_nl_get_link_net(const struct net_device *dev) +{ + struct ppp *ppp = netdev_priv(dev); + + return ppp->ppp_net; +} + +static struct rtnl_link_ops ppp_link_ops __read_mostly = { + .kind = "ppp", + .maxtype = IFLA_PPP_MAX, + .policy = ppp_nl_policy, + .priv_size = sizeof(struct ppp), + .setup = ppp_setup, + .validate = ppp_nl_validate, + .newlink = ppp_nl_newlink, + .dellink = ppp_nl_dellink, + .get_size = ppp_nl_get_size, + .fill_info = ppp_nl_fill_info, + .get_link_net = ppp_nl_get_link_net, +}; + #define PPP_MAJOR 108 /* Called at boot time if ppp is compiled into the kernel, @@ -1080,11 +1177,19 @@ static int __init ppp_init(void) goto out_chrdev; } + err = rtnl_link_register(&ppp_link_ops); + if (err) { + pr_err("failed to register rtnetlink PPP handler\n"); + goto out_class; + } + /* not a big deal if we fail here :-) */ device_create(ppp_class, NULL, MKDEV(PPP_MAJOR, 0), NULL, "ppp"); return 0; +out_class: + class_destroy(ppp_class); out_chrdev: unregister_chrdev(PPP_MAJOR, "ppp"); out_net: @@ -2829,6 +2934,7 @@ static int ppp_create_interface(struct net *net, struct file *file, int *unit) struct ppp_config conf = { .file = file, .unit = *unit, + .ifname_is_set = false, }; struct net_device *dev; struct ppp *ppp; @@ -2840,6 +2946,7 @@ static int ppp_create_interface(struct net *net, struct file *file, int *unit) goto err; } dev_net_set(dev, net); + dev->rtnl_link_ops = &ppp_link_ops; rtnl_lock(); @@ -3046,6 +3153,7 @@ static void __exit ppp_cleanup(void) /* should never happen */ if (atomic_read(&ppp_unit_count) || atomic_read(&channel_count)) pr_err("PPP: removing module but units remain!\n"); + rtnl_link_unregister(&ppp_link_ops); unregister_chrdev(PPP_MAJOR, "ppp"); device_destroy(ppp_class, MKDEV(PPP_MAJOR, 0)); class_destroy(ppp_class); @@ -3104,4 +3212,5 @@ EXPORT_SYMBOL(ppp_register_compressor); EXPORT_SYMBOL(ppp_unregister_compressor); MODULE_LICENSE("GPL"); MODULE_ALIAS_CHARDEV(PPP_MAJOR, 0); +MODULE_ALIAS_RTNL_LINK("ppp"); MODULE_ALIAS("devname:ppp"); diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index d82de331bb6b..3e80974566bb 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -520,6 +520,14 @@ enum { }; #define IFLA_GENEVE_MAX (__IFLA_GENEVE_MAX - 1) +/* PPP section */ +enum { + IFLA_PPP_UNSPEC, + IFLA_PPP_DEV_FD, + __IFLA_PPP_MAX +}; +#define IFLA_PPP_MAX (__IFLA_PPP_MAX - 1) + /* Bonding section */ enum { |