Commit e2748d7e authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'tuntap' 



Pavel Emelyanov says:

====================
tun: Some bits required for tun's checkpoint-restore (v2)

After taking a closer look on tun checkpoint-restore I've found several
issues with the tun's API that make it impossible to dump and restore
the state of tun device and attached tun-files.

The proposed API changes are all about extending the existing ioctl-based
stuff. Patches fit today's net-next.

This v2 has David's comments about patch #1 fixed. All the rest is the same.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 5f1cd200 76975e9c

drivers/net/tun.c

+40 −6
Original line number Diff line number Diff line
@@ -138,7 +138,10 @@ struct tun_file { 
	struct fasync_struct *fasync;

	/* only used for fasnyc */

	unsigned int flags;

	union {

		u16 queue_index;

		unsigned int ifindex;

	};

	struct list_head next;

	struct tun_struct *detached;

};
@@ -498,7 +501,7 @@ static void tun_detach_all(struct net_device *dev) 
		module_put(THIS_MODULE);

}



static int tun_attach(struct tun_struct *tun, struct file *file)

static int tun_attach(struct tun_struct *tun, struct file *file, bool skip_filter)

{

	struct tun_file *tfile = file->private_data;

	int err;
@@ -523,7 +526,7 @@ static int tun_attach(struct tun_struct *tun, struct file *file) 
	err = 0;



	/* Re-attach the filter to presist device */

	if (tun->filter_attached == true) {

	if (!skip_filter && (tun->filter_attached == true)) {

		err = sk_attach_filter(&tun->fprog, tfile->socket.sk);

		if (!err)

			goto out;
@@ -1554,7 +1557,7 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) 
		if (err < 0)

			return err;



		err = tun_attach(tun, file);

		err = tun_attach(tun, file, ifr->ifr_flags & IFF_NOFILTER);

		if (err < 0)

			return err;
@@ -1601,6 +1604,7 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) 


		dev_net_set(dev, net);

		dev->rtnl_link_ops = &tun_link_ops;

		dev->ifindex = tfile->ifindex;



		tun = netdev_priv(dev);

		tun->dev = dev;
@@ -1627,7 +1631,7 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) 
		dev->vlan_features = dev->features;



		INIT_LIST_HEAD(&tun->disabled);

		err = tun_attach(tun, file);

		err = tun_attach(tun, file, false);

		if (err < 0)

			goto err_free_dev;
@@ -1791,7 +1795,7 @@ static int tun_set_queue(struct file *file, struct ifreq *ifr) 
		ret = security_tun_dev_attach_queue(tun->security);

		if (ret < 0)

			goto unlock;

		ret = tun_attach(tun, file);

		ret = tun_attach(tun, file, false);

	} else if (ifr->ifr_flags & IFF_DETACH_QUEUE) {

		tun = rtnl_dereference(tfile->tun);

		if (!tun || !(tun->flags & TUN_TAP_MQ) || tfile->detached)
@@ -1817,6 +1821,7 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, 
	kgid_t group;

	int sndbuf;

	int vnet_hdr_sz;

	unsigned int ifindex;

	int ret;



	if (cmd == TUNSETIFF || cmd == TUNSETQUEUE || _IOC_TYPE(cmd) == 0x89) {
@@ -1851,6 +1856,19 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, 
			ret = -EFAULT;

		goto unlock;

	}

	if (cmd == TUNSETIFINDEX) {

		ret = -EPERM;

		if (tun)

			goto unlock;



		ret = -EFAULT;

		if (copy_from_user(&ifindex, argp, sizeof(ifindex)))

			goto unlock;



		ret = 0;

		tfile->ifindex = ifindex;

		goto unlock;

	}



	ret = -EBADFD;

	if (!tun)
@@ -1863,6 +1881,11 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, 
	case TUNGETIFF:

		tun_get_iff(current->nsproxy->net_ns, tun, &ifr);



		if (tfile->detached)

			ifr.ifr_flags |= IFF_DETACH_QUEUE;

		if (!tfile->socket.sk->sk_filter)

			ifr.ifr_flags |= IFF_NOFILTER;



		if (copy_to_user(argp, &ifr, ifreq_len))

			ret = -EFAULT;

		break;
@@ -2019,6 +2042,16 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, 
		tun_detach_filter(tun, tun->numqueues);

		break;



	case TUNGETFILTER:

		ret = -EINVAL;

		if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV)

			break;

		ret = -EFAULT;

		if (copy_to_user(argp, &tun->fprog, sizeof(tun->fprog)))

			break;

		ret = 0;

		break;



	default:

		ret = -EINVAL;

		break;
@@ -2099,6 +2132,7 @@ static int tun_chr_open(struct inode *inode, struct file * file) 
	rcu_assign_pointer(tfile->tun, NULL);

	tfile->net = get_net(current->nsproxy->net_ns);

	tfile->flags = 0;

	tfile->ifindex = 0;



	rcu_assign_pointer(tfile->socket.wq, &tfile->wq);

	init_waitqueue_head(&tfile->wq.wait);

include/uapi/linux/if_tun.h

+3 −0
Original line number Diff line number Diff line
@@ -56,6 +56,8 @@ 
#define TUNGETVNETHDRSZ _IOR('T', 215, int)

#define TUNSETVNETHDRSZ _IOW('T', 216, int)

#define TUNSETQUEUE  _IOW('T', 217, int)

#define TUNSETIFINDEX	_IOW('T', 218, unsigned int)

#define TUNGETFILTER _IOR('T', 219, struct sock_fprog)



/* TUNSETIFF ifr flags */

#define IFF_TUN		0x0001
@@ -70,6 +72,7 @@ 
#define IFF_DETACH_QUEUE 0x0400

/* read-only flag */

#define IFF_PERSIST	0x0800

#define IFF_NOFILTER	0x1000



/* Socket options */

#define TUN_TX_TIMESTAMP 1

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