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path: root/drivers/net/ppp/ppp_generic.c
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Diffstat (limited to 'drivers/net/ppp/ppp_generic.c')
-rw-r--r--drivers/net/ppp/ppp_generic.c320
1 files changed, 230 insertions, 90 deletions
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 <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>
@@ -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");