From 863981e96738983919de841ec669e157e6bdaeb0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Sun, 11 Sep 2016 04:34:46 -0300 Subject: Linux-libre 4.7.1-gnu --- drivers/net/ppp/ppp_generic.c | 320 ++++++++++++++++++++++++++++++------------ 1 file changed, 230 insertions(+), 90 deletions(-) (limited to 'drivers/net/ppp') diff --git a/drivers/net/ppp/ppp_generic.c b/drivers/net/ppp/ppp_generic.c index f572b31a2..a30ee427e 100644 --- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -46,6 +46,7 @@ #include #include #include +#include #include #include #include @@ -183,6 +184,12 @@ struct channel { #endif /* CONFIG_PPP_MULTILINK */ }; +struct ppp_config { + struct file *file; + s32 unit; + bool ifname_is_set; +}; + /* * SMP locking issues: * Both the ppp.rlock and ppp.wlock locks protect the ppp.channels @@ -269,8 +276,7 @@ static void ppp_ccp_peek(struct ppp *ppp, struct sk_buff *skb, int inbound); static void ppp_ccp_closed(struct ppp *ppp); static struct compressor *find_compressor(int type); static void ppp_get_stats(struct ppp *ppp, struct ppp_stats *st); -static struct ppp *ppp_create_interface(struct net *net, int unit, - struct file *file, int *retp); +static int ppp_create_interface(struct net *net, struct file *file, int *unit); static void init_ppp_file(struct ppp_file *pf, int kind); static void ppp_destroy_interface(struct ppp *ppp); static struct ppp *ppp_find_unit(struct ppp_net *pn, int unit); @@ -282,6 +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; @@ -853,12 +860,12 @@ static int ppp_unattached_ioctl(struct net *net, struct ppp_file *pf, /* Create a new ppp unit */ if (get_user(unit, p)) break; - ppp = ppp_create_interface(net, unit, file, &err); - if (!ppp) + err = ppp_create_interface(net, file, &unit); + if (err < 0) break; - file->private_data = &ppp->file; + err = -EFAULT; - if (put_user(ppp->file.index, p)) + if (put_user(unit, p)) break; err = 0; break; @@ -960,6 +967,188 @@ static struct pernet_operations ppp_net_ops = { .size = sizeof(struct ppp_net), }; +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; + + mutex_lock(&pn->all_ppp_mutex); + + if (unit < 0) { + ret = unit_get(&pn->units_idr, ppp); + if (ret < 0) + goto err; + } else { + /* Caller asked for a specific unit number. Fail with -EEXIST + * if unavailable. For backward compatibility, return -EEXIST + * too if idr allocation fails; this makes pppd retry without + * requesting a specific unit number. + */ + if (unit_find(&pn->units_idr, unit)) { + ret = -EEXIST; + goto err; + } + ret = unit_set(&pn->units_idr, ppp, unit); + if (ret < 0) { + /* Rewrite error for backward compatibility */ + ret = -EEXIST; + goto err; + } + } + ppp->file.index = ret; + + if (!ifname_is_set) + snprintf(ppp->dev->name, IFNAMSIZ, "ppp%i", ppp->file.index); + + ret = register_netdevice(ppp->dev); + if (ret < 0) + goto err_unit; + + atomic_inc(&ppp_unit_count); + + mutex_unlock(&pn->all_ppp_mutex); + + return 0; + +err_unit: + unit_put(&pn->units_idr, ppp->file.index); +err: + mutex_unlock(&pn->all_ppp_mutex); + + return ret; +} + +static int ppp_dev_configure(struct net *src_net, struct net_device *dev, + const struct ppp_config *conf) +{ + struct ppp *ppp = netdev_priv(dev); + int indx; + int err; + + ppp->dev = dev; + ppp->ppp_net = src_net; + ppp->mru = PPP_MRU; + ppp->owner = conf->file; + + init_ppp_file(&ppp->file, INTERFACE); + ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */ + + for (indx = 0; indx < NUM_NP; ++indx) + ppp->npmode[indx] = NPMODE_PASS; + INIT_LIST_HEAD(&ppp->channels); + spin_lock_init(&ppp->rlock); + spin_lock_init(&ppp->wlock); +#ifdef CONFIG_PPP_MULTILINK + ppp->minseq = -1; + skb_queue_head_init(&ppp->mrq); +#endif /* CONFIG_PPP_MULTILINK */ +#ifdef CONFIG_PPP_FILTER + ppp->pass_filter = NULL; + ppp->active_filter = NULL; +#endif /* CONFIG_PPP_FILTER */ + + err = ppp_unit_register(ppp, conf->unit, conf->ifname_is_set); + if (err < 0) + return err; + + conf->file->private_data = &ppp->file; + + 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, @@ -988,11 +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: @@ -2404,8 +2601,6 @@ ppp_unregister_channel(struct ppp_channel *chan) spin_lock_bh(&pn->all_channels_lock); list_del(&pch->list); spin_unlock_bh(&pn->all_channels_lock); - put_net(pch->chan_net); - pch->chan_net = NULL; pch->file.dead = 1; wake_up_interruptible(&pch->file.rwait); @@ -2732,102 +2927,42 @@ ppp_get_stats(struct ppp *ppp, struct ppp_stats *st) * or if there is already a unit with the requested number. * unit == -1 means allocate a new number. */ -static struct ppp *ppp_create_interface(struct net *net, int unit, - struct file *file, int *retp) +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; - struct ppp_net *pn; - struct net_device *dev = NULL; - int ret = -ENOMEM; - int i; + int err; dev = alloc_netdev(sizeof(struct ppp), "", NET_NAME_ENUM, ppp_setup); - if (!dev) - goto out1; - - pn = ppp_pernet(net); - - ppp = netdev_priv(dev); - ppp->dev = dev; - ppp->mru = PPP_MRU; - init_ppp_file(&ppp->file, INTERFACE); - ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */ - ppp->owner = file; - for (i = 0; i < NUM_NP; ++i) - ppp->npmode[i] = NPMODE_PASS; - INIT_LIST_HEAD(&ppp->channels); - spin_lock_init(&ppp->rlock); - spin_lock_init(&ppp->wlock); -#ifdef CONFIG_PPP_MULTILINK - ppp->minseq = -1; - skb_queue_head_init(&ppp->mrq); -#endif /* CONFIG_PPP_MULTILINK */ -#ifdef CONFIG_PPP_FILTER - ppp->pass_filter = NULL; - ppp->active_filter = NULL; -#endif /* CONFIG_PPP_FILTER */ - - /* - * drum roll: don't forget to set - * the net device is belong to - */ + if (!dev) { + err = -ENOMEM; + goto err; + } dev_net_set(dev, net); + dev->rtnl_link_ops = &ppp_link_ops; rtnl_lock(); - mutex_lock(&pn->all_ppp_mutex); - if (unit < 0) { - unit = unit_get(&pn->units_idr, ppp); - if (unit < 0) { - ret = unit; - goto out2; - } - } else { - ret = -EEXIST; - if (unit_find(&pn->units_idr, unit)) - goto out2; /* unit already exists */ - /* - * if caller need a specified unit number - * lets try to satisfy him, otherwise -- - * he should better ask us for new unit number - * - * NOTE: yes I know that returning EEXIST it's not - * fair but at least pppd will ask us to allocate - * new unit in this case so user is happy :) - */ - unit = unit_set(&pn->units_idr, ppp, unit); - if (unit < 0) - goto out2; - } - - /* Initialize the new ppp unit */ - ppp->file.index = unit; - sprintf(dev->name, "ppp%d", unit); - - ret = register_netdevice(dev); - if (ret != 0) { - unit_put(&pn->units_idr, unit); - netdev_err(ppp->dev, "PPP: couldn't register device %s (%d)\n", - dev->name, ret); - goto out2; - } - - ppp->ppp_net = net; + err = ppp_dev_configure(net, dev, &conf); + if (err < 0) + goto err_dev; + ppp = netdev_priv(dev); + *unit = ppp->file.index; - atomic_inc(&ppp_unit_count); - mutex_unlock(&pn->all_ppp_mutex); rtnl_unlock(); - *retp = 0; - return ppp; + return 0; -out2: - mutex_unlock(&pn->all_ppp_mutex); +err_dev: rtnl_unlock(); free_netdev(dev); -out1: - *retp = ret; - return NULL; +err: + return err; } /* @@ -2999,6 +3134,9 @@ ppp_disconnect_channel(struct channel *pch) */ static void ppp_destroy_channel(struct channel *pch) { + put_net(pch->chan_net); + pch->chan_net = NULL; + atomic_dec(&channel_count); if (!pch->file.dead) { @@ -3016,6 +3154,7 @@ 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); @@ -3074,4 +3213,5 @@ 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"); -- cgit v1.2.3-54-g00ecf