![Craig Gallek](/assets/img/avatar_default.png)
The referenced change added a netlink notifier for processing
device queue size events. These events are fired for all devices
but the registered callback assumed they only occurred for tun
devices. This fix adds a check (borrowed from macvtap.c) to discard
non-tun device events.
For reference, this fixes the following splat:
[ 71.505935] BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
[ 71.513870] IP: [<ffffffff8153c1a0>] tun_device_event+0x110/0x340
[ 71.519906] PGD 3f41f56067 PUD 3f264b7067 PMD 0
[ 71.524497] Oops: 0002 [#1] SMP DEBUG_PAGEALLOC
[ 71.529374] gsmi: Log Shutdown Reason 0x03
[ 71.533417] Modules linked in:[ 71.533826] mlx4_en: eth1: Link Up
[ 71.539616] bonding w1_therm wire cdc_acm ehci_pci ehci_hcd mlx4_en ib_uverbs mlx4_ib ib_core mlx4_core
[ 71.549282] CPU: 12 PID: 7915 Comm: set.ixion-haswe Not tainted 4.7.0-dbx-DEV #8
[ 71.556586] Hardware name: Intel Grantley,Wellsburg/Ixion_IT_15, BIOS 2.58.0 05/03/2016
[ 71.564495] task: ffff887f00bb20c0 ti: ffff887f00798000 task.ti: ffff887f00798000
[ 71.571894] RIP: 0010:[<ffffffff8153c1a0>] [<ffffffff8153c1a0>] tun_device_event+0x110/0x340
[ 71.580327] RSP: 0018:ffff887f0079bbd8 EFLAGS: 00010202
[ 71.585576] RAX: fffffffffffffae8 RBX: ffff887ef6d03378 RCX: 0000000000000000
[ 71.592624] RDX: 0000000000000000 RSI: 0000000000000028 RDI: 0000000000000000
[ 71.599675] RBP: ffff887f0079bc48 R08: 0000000000000000 R09: 0000000000000001
[ 71.606730] R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000010
[ 71.613780] R13: 0000000000000000 R14: 0000000000000001 R15: ffff887f0079bd00
[ 71.620832] FS: 00007f5cdc581700(0000) GS:ffff883f7f700000(0000) knlGS:0000000000000000
[ 71.628826] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 71.634500] CR2: 0000000000000010 CR3: 0000003f3eb62000 CR4: 00000000001406e0
[ 71.641549] Stack:
[ 71.643533] ffff887f0079bc08 0000000000000246 000000000000001e ffff887ef6d00000
[ 71.650871] ffff887f0079bd00 0000000000000000 0000000000000000 ffffffff00000000
[ 71.658210] ffff887f0079bc48 ffffffff81d24070 00000000fffffff9 ffffffff81cec7a0
[ 71.665549] Call Trace:
[ 71.667975] [<ffffffff810eeb0d>] notifier_call_chain+0x5d/0x80
[ 71.673823] [<ffffffff816365d0>] ? show_tx_maxrate+0x30/0x30
[ 71.679502] [<ffffffff810eeb3e>] __raw_notifier_call_chain+0xe/0x10
[ 71.685778] [<ffffffff810eeb56>] raw_notifier_call_chain+0x16/0x20
[ 71.691976] [<ffffffff8160eb30>] call_netdevice_notifiers_info+0x40/0x70
[ 71.698681] [<ffffffff8160ec36>] call_netdevice_notifiers+0x16/0x20
[ 71.704956] [<ffffffff81636636>] change_tx_queue_len+0x66/0x90
[ 71.710807] [<ffffffff816381ef>] netdev_store.isra.5+0xbf/0xd0
[ 71.716658] [<ffffffff81638350>] tx_queue_len_store+0x50/0x60
[ 71.722431] [<ffffffff814a6798>] dev_attr_store+0x18/0x30
[ 71.727857] [<ffffffff812ea3ff>] sysfs_kf_write+0x4f/0x70
[ 71.733274] [<ffffffff812e9507>] kernfs_fop_write+0x147/0x1d0
[ 71.739045] [<ffffffff81134a4f>] ? rcu_read_lock_sched_held+0x8f/0xa0
[ 71.745499] [<ffffffff8125a108>] __vfs_write+0x28/0x120
[ 71.750748] [<ffffffff8111b137>] ? percpu_down_read+0x57/0x90
[ 71.756516] [<ffffffff8125d7d8>] ? __sb_start_write+0xc8/0xe0
[ 71.762278] [<ffffffff8125d7d8>] ? __sb_start_write+0xc8/0xe0
[ 71.768038] [<ffffffff8125bd5e>] vfs_write+0xbe/0x1b0
[ 71.773113] [<ffffffff8125c092>] SyS_write+0x52/0xa0
[ 71.778110] [<ffffffff817528e5>] entry_SYSCALL_64_fastpath+0x18/0xa8
[ 71.784472] Code: 45 31 f6 48 8b 93 78 33 00 00 48 81 c3 78 33 00 00 48 39 d3 48 8d 82 e8 fa ff ff 74 25 48 8d b0 40 05 00 00 49 63 d6 41 83 c6 01 <49> 89 34 d4 48 8b 90 18 05 00 00 48 39 d3 48 8d 82 e8 fa ff ff
[ 71.803655] RIP [<ffffffff8153c1a0>] tun_device_event+0x110/0x340
[ 71.809769] RSP <ffff887f0079bbd8>
[ 71.813213] CR2: 0000000000000010
[ 71.816512] ---[ end trace 4db6449606319f73 ]---
Fixes: 1576d98605
("tun: switch to use skb array for tx")
Signed-off-by: Craig Gallek <kraig@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2582 lines
60 KiB
C
2582 lines
60 KiB
C
/*
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* TUN - Universal TUN/TAP device driver.
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* Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $
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*/
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/*
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* Changes:
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*
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* Mike Kershaw <dragorn@kismetwireless.net> 2005/08/14
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* Add TUNSETLINK ioctl to set the link encapsulation
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*
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* Mark Smith <markzzzsmith@yahoo.com.au>
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* Use eth_random_addr() for tap MAC address.
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*
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* Harald Roelle <harald.roelle@ifi.lmu.de> 2004/04/20
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* Fixes in packet dropping, queue length setting and queue wakeup.
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* Increased default tx queue length.
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* Added ethtool API.
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* Minor cleanups
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*
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* Daniel Podlejski <underley@underley.eu.org>
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* Modifications for 2.3.99-pre5 kernel.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#define DRV_NAME "tun"
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#define DRV_VERSION "1.6"
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#define DRV_DESCRIPTION "Universal TUN/TAP device driver"
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#define DRV_COPYRIGHT "(C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>"
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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/major.h>
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#include <linux/slab.h>
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#include <linux/poll.h>
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#include <linux/fcntl.h>
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#include <linux/init.h>
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#include <linux/skbuff.h>
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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#include <linux/miscdevice.h>
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#include <linux/ethtool.h>
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#include <linux/rtnetlink.h>
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#include <linux/compat.h>
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#include <linux/if.h>
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#include <linux/if_arp.h>
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#include <linux/if_ether.h>
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#include <linux/if_tun.h>
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#include <linux/if_vlan.h>
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#include <linux/crc32.h>
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#include <linux/nsproxy.h>
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#include <linux/virtio_net.h>
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#include <linux/rcupdate.h>
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#include <net/net_namespace.h>
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#include <net/netns/generic.h>
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#include <net/rtnetlink.h>
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#include <net/sock.h>
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#include <linux/seq_file.h>
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#include <linux/uio.h>
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#include <linux/skb_array.h>
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#include <asm/uaccess.h>
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/* Uncomment to enable debugging */
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/* #define TUN_DEBUG 1 */
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#ifdef TUN_DEBUG
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static int debug;
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#define tun_debug(level, tun, fmt, args...) \
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do { \
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if (tun->debug) \
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netdev_printk(level, tun->dev, fmt, ##args); \
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} while (0)
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#define DBG1(level, fmt, args...) \
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do { \
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if (debug == 2) \
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printk(level fmt, ##args); \
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} while (0)
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#else
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#define tun_debug(level, tun, fmt, args...) \
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do { \
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if (0) \
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netdev_printk(level, tun->dev, fmt, ##args); \
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} while (0)
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#define DBG1(level, fmt, args...) \
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do { \
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if (0) \
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printk(level fmt, ##args); \
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} while (0)
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#endif
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/* TUN device flags */
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/* IFF_ATTACH_QUEUE is never stored in device flags,
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* overload it to mean fasync when stored there.
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*/
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#define TUN_FASYNC IFF_ATTACH_QUEUE
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/* High bits in flags field are unused. */
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#define TUN_VNET_LE 0x80000000
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#define TUN_VNET_BE 0x40000000
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#define TUN_FEATURES (IFF_NO_PI | IFF_ONE_QUEUE | IFF_VNET_HDR | \
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IFF_MULTI_QUEUE)
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#define GOODCOPY_LEN 128
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#define FLT_EXACT_COUNT 8
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struct tap_filter {
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unsigned int count; /* Number of addrs. Zero means disabled */
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u32 mask[2]; /* Mask of the hashed addrs */
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unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN];
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};
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/* MAX_TAP_QUEUES 256 is chosen to allow rx/tx queues to be equal
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* to max number of VCPUs in guest. */
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#define MAX_TAP_QUEUES 256
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#define MAX_TAP_FLOWS 4096
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#define TUN_FLOW_EXPIRE (3 * HZ)
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struct tun_pcpu_stats {
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u64 rx_packets;
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u64 rx_bytes;
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u64 tx_packets;
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u64 tx_bytes;
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struct u64_stats_sync syncp;
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u32 rx_dropped;
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u32 tx_dropped;
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u32 rx_frame_errors;
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};
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/* A tun_file connects an open character device to a tuntap netdevice. It
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* also contains all socket related structures (except sock_fprog and tap_filter)
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* to serve as one transmit queue for tuntap device. The sock_fprog and
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* tap_filter were kept in tun_struct since they were used for filtering for the
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* netdevice not for a specific queue (at least I didn't see the requirement for
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* this).
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*
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* RCU usage:
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* The tun_file and tun_struct are loosely coupled, the pointer from one to the
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* other can only be read while rcu_read_lock or rtnl_lock is held.
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*/
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struct tun_file {
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struct sock sk;
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struct socket socket;
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struct socket_wq wq;
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struct tun_struct __rcu *tun;
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struct fasync_struct *fasync;
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/* only used for fasnyc */
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unsigned int flags;
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union {
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u16 queue_index;
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unsigned int ifindex;
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};
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struct list_head next;
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struct tun_struct *detached;
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struct skb_array tx_array;
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};
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struct tun_flow_entry {
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struct hlist_node hash_link;
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struct rcu_head rcu;
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struct tun_struct *tun;
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u32 rxhash;
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u32 rps_rxhash;
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int queue_index;
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unsigned long updated;
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};
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#define TUN_NUM_FLOW_ENTRIES 1024
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/* Since the socket were moved to tun_file, to preserve the behavior of persist
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* device, socket filter, sndbuf and vnet header size were restore when the
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* file were attached to a persist device.
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*/
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struct tun_struct {
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struct tun_file __rcu *tfiles[MAX_TAP_QUEUES];
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unsigned int numqueues;
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unsigned int flags;
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kuid_t owner;
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kgid_t group;
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struct net_device *dev;
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netdev_features_t set_features;
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#define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \
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NETIF_F_TSO6|NETIF_F_UFO)
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int align;
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int vnet_hdr_sz;
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int sndbuf;
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struct tap_filter txflt;
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struct sock_fprog fprog;
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/* protected by rtnl lock */
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bool filter_attached;
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#ifdef TUN_DEBUG
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int debug;
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#endif
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spinlock_t lock;
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struct hlist_head flows[TUN_NUM_FLOW_ENTRIES];
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struct timer_list flow_gc_timer;
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unsigned long ageing_time;
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unsigned int numdisabled;
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struct list_head disabled;
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void *security;
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u32 flow_count;
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struct tun_pcpu_stats __percpu *pcpu_stats;
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};
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#ifdef CONFIG_TUN_VNET_CROSS_LE
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static inline bool tun_legacy_is_little_endian(struct tun_struct *tun)
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{
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return tun->flags & TUN_VNET_BE ? false :
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virtio_legacy_is_little_endian();
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}
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static long tun_get_vnet_be(struct tun_struct *tun, int __user *argp)
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{
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int be = !!(tun->flags & TUN_VNET_BE);
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if (put_user(be, argp))
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return -EFAULT;
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return 0;
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}
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static long tun_set_vnet_be(struct tun_struct *tun, int __user *argp)
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{
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int be;
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if (get_user(be, argp))
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return -EFAULT;
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if (be)
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tun->flags |= TUN_VNET_BE;
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else
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tun->flags &= ~TUN_VNET_BE;
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return 0;
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}
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#else
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static inline bool tun_legacy_is_little_endian(struct tun_struct *tun)
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{
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return virtio_legacy_is_little_endian();
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}
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static long tun_get_vnet_be(struct tun_struct *tun, int __user *argp)
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{
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return -EINVAL;
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}
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static long tun_set_vnet_be(struct tun_struct *tun, int __user *argp)
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{
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return -EINVAL;
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}
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#endif /* CONFIG_TUN_VNET_CROSS_LE */
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static inline bool tun_is_little_endian(struct tun_struct *tun)
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{
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return tun->flags & TUN_VNET_LE ||
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tun_legacy_is_little_endian(tun);
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}
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static inline u16 tun16_to_cpu(struct tun_struct *tun, __virtio16 val)
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{
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return __virtio16_to_cpu(tun_is_little_endian(tun), val);
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}
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static inline __virtio16 cpu_to_tun16(struct tun_struct *tun, u16 val)
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{
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return __cpu_to_virtio16(tun_is_little_endian(tun), val);
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}
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static inline u32 tun_hashfn(u32 rxhash)
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{
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return rxhash & 0x3ff;
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}
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static struct tun_flow_entry *tun_flow_find(struct hlist_head *head, u32 rxhash)
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{
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struct tun_flow_entry *e;
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hlist_for_each_entry_rcu(e, head, hash_link) {
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if (e->rxhash == rxhash)
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return e;
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}
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return NULL;
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}
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static struct tun_flow_entry *tun_flow_create(struct tun_struct *tun,
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struct hlist_head *head,
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u32 rxhash, u16 queue_index)
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{
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struct tun_flow_entry *e = kmalloc(sizeof(*e), GFP_ATOMIC);
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if (e) {
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tun_debug(KERN_INFO, tun, "create flow: hash %u index %u\n",
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rxhash, queue_index);
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e->updated = jiffies;
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e->rxhash = rxhash;
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e->rps_rxhash = 0;
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e->queue_index = queue_index;
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e->tun = tun;
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hlist_add_head_rcu(&e->hash_link, head);
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++tun->flow_count;
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}
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return e;
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}
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static void tun_flow_delete(struct tun_struct *tun, struct tun_flow_entry *e)
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{
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tun_debug(KERN_INFO, tun, "delete flow: hash %u index %u\n",
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e->rxhash, e->queue_index);
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hlist_del_rcu(&e->hash_link);
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kfree_rcu(e, rcu);
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--tun->flow_count;
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}
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static void tun_flow_flush(struct tun_struct *tun)
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{
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int i;
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spin_lock_bh(&tun->lock);
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for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) {
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struct tun_flow_entry *e;
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struct hlist_node *n;
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hlist_for_each_entry_safe(e, n, &tun->flows[i], hash_link)
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tun_flow_delete(tun, e);
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}
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spin_unlock_bh(&tun->lock);
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}
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static void tun_flow_delete_by_queue(struct tun_struct *tun, u16 queue_index)
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{
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int i;
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spin_lock_bh(&tun->lock);
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for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) {
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struct tun_flow_entry *e;
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struct hlist_node *n;
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hlist_for_each_entry_safe(e, n, &tun->flows[i], hash_link) {
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if (e->queue_index == queue_index)
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tun_flow_delete(tun, e);
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}
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}
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spin_unlock_bh(&tun->lock);
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}
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static void tun_flow_cleanup(unsigned long data)
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{
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struct tun_struct *tun = (struct tun_struct *)data;
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unsigned long delay = tun->ageing_time;
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unsigned long next_timer = jiffies + delay;
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unsigned long count = 0;
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int i;
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tun_debug(KERN_INFO, tun, "tun_flow_cleanup\n");
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spin_lock_bh(&tun->lock);
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for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) {
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struct tun_flow_entry *e;
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struct hlist_node *n;
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hlist_for_each_entry_safe(e, n, &tun->flows[i], hash_link) {
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unsigned long this_timer;
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count++;
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this_timer = e->updated + delay;
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if (time_before_eq(this_timer, jiffies))
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tun_flow_delete(tun, e);
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else if (time_before(this_timer, next_timer))
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next_timer = this_timer;
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}
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}
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if (count)
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mod_timer(&tun->flow_gc_timer, round_jiffies_up(next_timer));
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spin_unlock_bh(&tun->lock);
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}
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static void tun_flow_update(struct tun_struct *tun, u32 rxhash,
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struct tun_file *tfile)
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{
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|
struct hlist_head *head;
|
|
struct tun_flow_entry *e;
|
|
unsigned long delay = tun->ageing_time;
|
|
u16 queue_index = tfile->queue_index;
|
|
|
|
if (!rxhash)
|
|
return;
|
|
else
|
|
head = &tun->flows[tun_hashfn(rxhash)];
|
|
|
|
rcu_read_lock();
|
|
|
|
/* We may get a very small possibility of OOO during switching, not
|
|
* worth to optimize.*/
|
|
if (tun->numqueues == 1 || tfile->detached)
|
|
goto unlock;
|
|
|
|
e = tun_flow_find(head, rxhash);
|
|
if (likely(e)) {
|
|
/* TODO: keep queueing to old queue until it's empty? */
|
|
e->queue_index = queue_index;
|
|
e->updated = jiffies;
|
|
sock_rps_record_flow_hash(e->rps_rxhash);
|
|
} else {
|
|
spin_lock_bh(&tun->lock);
|
|
if (!tun_flow_find(head, rxhash) &&
|
|
tun->flow_count < MAX_TAP_FLOWS)
|
|
tun_flow_create(tun, head, rxhash, queue_index);
|
|
|
|
if (!timer_pending(&tun->flow_gc_timer))
|
|
mod_timer(&tun->flow_gc_timer,
|
|
round_jiffies_up(jiffies + delay));
|
|
spin_unlock_bh(&tun->lock);
|
|
}
|
|
|
|
unlock:
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
/**
|
|
* Save the hash received in the stack receive path and update the
|
|
* flow_hash table accordingly.
|
|
*/
|
|
static inline void tun_flow_save_rps_rxhash(struct tun_flow_entry *e, u32 hash)
|
|
{
|
|
if (unlikely(e->rps_rxhash != hash))
|
|
e->rps_rxhash = hash;
|
|
}
|
|
|
|
/* We try to identify a flow through its rxhash first. The reason that
|
|
* we do not check rxq no. is because some cards(e.g 82599), chooses
|
|
* the rxq based on the txq where the last packet of the flow comes. As
|
|
* the userspace application move between processors, we may get a
|
|
* different rxq no. here. If we could not get rxhash, then we would
|
|
* hope the rxq no. may help here.
|
|
*/
|
|
static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb,
|
|
void *accel_priv, select_queue_fallback_t fallback)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
struct tun_flow_entry *e;
|
|
u32 txq = 0;
|
|
u32 numqueues = 0;
|
|
|
|
rcu_read_lock();
|
|
numqueues = ACCESS_ONCE(tun->numqueues);
|
|
|
|
txq = skb_get_hash(skb);
|
|
if (txq) {
|
|
e = tun_flow_find(&tun->flows[tun_hashfn(txq)], txq);
|
|
if (e) {
|
|
tun_flow_save_rps_rxhash(e, txq);
|
|
txq = e->queue_index;
|
|
} else
|
|
/* use multiply and shift instead of expensive divide */
|
|
txq = ((u64)txq * numqueues) >> 32;
|
|
} else if (likely(skb_rx_queue_recorded(skb))) {
|
|
txq = skb_get_rx_queue(skb);
|
|
while (unlikely(txq >= numqueues))
|
|
txq -= numqueues;
|
|
}
|
|
|
|
rcu_read_unlock();
|
|
return txq;
|
|
}
|
|
|
|
static inline bool tun_not_capable(struct tun_struct *tun)
|
|
{
|
|
const struct cred *cred = current_cred();
|
|
struct net *net = dev_net(tun->dev);
|
|
|
|
return ((uid_valid(tun->owner) && !uid_eq(cred->euid, tun->owner)) ||
|
|
(gid_valid(tun->group) && !in_egroup_p(tun->group))) &&
|
|
!ns_capable(net->user_ns, CAP_NET_ADMIN);
|
|
}
|
|
|
|
static void tun_set_real_num_queues(struct tun_struct *tun)
|
|
{
|
|
netif_set_real_num_tx_queues(tun->dev, tun->numqueues);
|
|
netif_set_real_num_rx_queues(tun->dev, tun->numqueues);
|
|
}
|
|
|
|
static void tun_disable_queue(struct tun_struct *tun, struct tun_file *tfile)
|
|
{
|
|
tfile->detached = tun;
|
|
list_add_tail(&tfile->next, &tun->disabled);
|
|
++tun->numdisabled;
|
|
}
|
|
|
|
static struct tun_struct *tun_enable_queue(struct tun_file *tfile)
|
|
{
|
|
struct tun_struct *tun = tfile->detached;
|
|
|
|
tfile->detached = NULL;
|
|
list_del_init(&tfile->next);
|
|
--tun->numdisabled;
|
|
return tun;
|
|
}
|
|
|
|
static void tun_queue_purge(struct tun_file *tfile)
|
|
{
|
|
struct sk_buff *skb;
|
|
|
|
while ((skb = skb_array_consume(&tfile->tx_array)) != NULL)
|
|
kfree_skb(skb);
|
|
|
|
skb_queue_purge(&tfile->sk.sk_error_queue);
|
|
}
|
|
|
|
static void __tun_detach(struct tun_file *tfile, bool clean)
|
|
{
|
|
struct tun_file *ntfile;
|
|
struct tun_struct *tun;
|
|
|
|
tun = rtnl_dereference(tfile->tun);
|
|
|
|
if (tun && !tfile->detached) {
|
|
u16 index = tfile->queue_index;
|
|
BUG_ON(index >= tun->numqueues);
|
|
|
|
rcu_assign_pointer(tun->tfiles[index],
|
|
tun->tfiles[tun->numqueues - 1]);
|
|
ntfile = rtnl_dereference(tun->tfiles[index]);
|
|
ntfile->queue_index = index;
|
|
|
|
--tun->numqueues;
|
|
if (clean) {
|
|
RCU_INIT_POINTER(tfile->tun, NULL);
|
|
sock_put(&tfile->sk);
|
|
} else
|
|
tun_disable_queue(tun, tfile);
|
|
|
|
synchronize_net();
|
|
tun_flow_delete_by_queue(tun, tun->numqueues + 1);
|
|
/* Drop read queue */
|
|
tun_queue_purge(tfile);
|
|
tun_set_real_num_queues(tun);
|
|
} else if (tfile->detached && clean) {
|
|
tun = tun_enable_queue(tfile);
|
|
sock_put(&tfile->sk);
|
|
}
|
|
|
|
if (clean) {
|
|
if (tun && tun->numqueues == 0 && tun->numdisabled == 0) {
|
|
netif_carrier_off(tun->dev);
|
|
|
|
if (!(tun->flags & IFF_PERSIST) &&
|
|
tun->dev->reg_state == NETREG_REGISTERED)
|
|
unregister_netdevice(tun->dev);
|
|
}
|
|
if (tun)
|
|
skb_array_cleanup(&tfile->tx_array);
|
|
sock_put(&tfile->sk);
|
|
}
|
|
}
|
|
|
|
static void tun_detach(struct tun_file *tfile, bool clean)
|
|
{
|
|
rtnl_lock();
|
|
__tun_detach(tfile, clean);
|
|
rtnl_unlock();
|
|
}
|
|
|
|
static void tun_detach_all(struct net_device *dev)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
struct tun_file *tfile, *tmp;
|
|
int i, n = tun->numqueues;
|
|
|
|
for (i = 0; i < n; i++) {
|
|
tfile = rtnl_dereference(tun->tfiles[i]);
|
|
BUG_ON(!tfile);
|
|
tfile->socket.sk->sk_shutdown = RCV_SHUTDOWN;
|
|
tfile->socket.sk->sk_data_ready(tfile->socket.sk);
|
|
RCU_INIT_POINTER(tfile->tun, NULL);
|
|
--tun->numqueues;
|
|
}
|
|
list_for_each_entry(tfile, &tun->disabled, next) {
|
|
tfile->socket.sk->sk_shutdown = RCV_SHUTDOWN;
|
|
tfile->socket.sk->sk_data_ready(tfile->socket.sk);
|
|
RCU_INIT_POINTER(tfile->tun, NULL);
|
|
}
|
|
BUG_ON(tun->numqueues != 0);
|
|
|
|
synchronize_net();
|
|
for (i = 0; i < n; i++) {
|
|
tfile = rtnl_dereference(tun->tfiles[i]);
|
|
/* Drop read queue */
|
|
tun_queue_purge(tfile);
|
|
sock_put(&tfile->sk);
|
|
}
|
|
list_for_each_entry_safe(tfile, tmp, &tun->disabled, next) {
|
|
tun_enable_queue(tfile);
|
|
tun_queue_purge(tfile);
|
|
sock_put(&tfile->sk);
|
|
}
|
|
BUG_ON(tun->numdisabled != 0);
|
|
|
|
if (tun->flags & IFF_PERSIST)
|
|
module_put(THIS_MODULE);
|
|
}
|
|
|
|
static int tun_attach(struct tun_struct *tun, struct file *file, bool skip_filter)
|
|
{
|
|
struct tun_file *tfile = file->private_data;
|
|
struct net_device *dev = tun->dev;
|
|
int err;
|
|
|
|
err = security_tun_dev_attach(tfile->socket.sk, tun->security);
|
|
if (err < 0)
|
|
goto out;
|
|
|
|
err = -EINVAL;
|
|
if (rtnl_dereference(tfile->tun) && !tfile->detached)
|
|
goto out;
|
|
|
|
err = -EBUSY;
|
|
if (!(tun->flags & IFF_MULTI_QUEUE) && tun->numqueues == 1)
|
|
goto out;
|
|
|
|
err = -E2BIG;
|
|
if (!tfile->detached &&
|
|
tun->numqueues + tun->numdisabled == MAX_TAP_QUEUES)
|
|
goto out;
|
|
|
|
err = 0;
|
|
|
|
/* Re-attach the filter to persist device */
|
|
if (!skip_filter && (tun->filter_attached == true)) {
|
|
lock_sock(tfile->socket.sk);
|
|
err = sk_attach_filter(&tun->fprog, tfile->socket.sk);
|
|
release_sock(tfile->socket.sk);
|
|
if (!err)
|
|
goto out;
|
|
}
|
|
|
|
if (!tfile->detached &&
|
|
skb_array_init(&tfile->tx_array, dev->tx_queue_len, GFP_KERNEL)) {
|
|
err = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
tfile->queue_index = tun->numqueues;
|
|
tfile->socket.sk->sk_shutdown &= ~RCV_SHUTDOWN;
|
|
rcu_assign_pointer(tfile->tun, tun);
|
|
rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile);
|
|
tun->numqueues++;
|
|
|
|
if (tfile->detached)
|
|
tun_enable_queue(tfile);
|
|
else
|
|
sock_hold(&tfile->sk);
|
|
|
|
tun_set_real_num_queues(tun);
|
|
|
|
/* device is allowed to go away first, so no need to hold extra
|
|
* refcnt.
|
|
*/
|
|
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static struct tun_struct *__tun_get(struct tun_file *tfile)
|
|
{
|
|
struct tun_struct *tun;
|
|
|
|
rcu_read_lock();
|
|
tun = rcu_dereference(tfile->tun);
|
|
if (tun)
|
|
dev_hold(tun->dev);
|
|
rcu_read_unlock();
|
|
|
|
return tun;
|
|
}
|
|
|
|
static struct tun_struct *tun_get(struct file *file)
|
|
{
|
|
return __tun_get(file->private_data);
|
|
}
|
|
|
|
static void tun_put(struct tun_struct *tun)
|
|
{
|
|
dev_put(tun->dev);
|
|
}
|
|
|
|
/* TAP filtering */
|
|
static void addr_hash_set(u32 *mask, const u8 *addr)
|
|
{
|
|
int n = ether_crc(ETH_ALEN, addr) >> 26;
|
|
mask[n >> 5] |= (1 << (n & 31));
|
|
}
|
|
|
|
static unsigned int addr_hash_test(const u32 *mask, const u8 *addr)
|
|
{
|
|
int n = ether_crc(ETH_ALEN, addr) >> 26;
|
|
return mask[n >> 5] & (1 << (n & 31));
|
|
}
|
|
|
|
static int update_filter(struct tap_filter *filter, void __user *arg)
|
|
{
|
|
struct { u8 u[ETH_ALEN]; } *addr;
|
|
struct tun_filter uf;
|
|
int err, alen, n, nexact;
|
|
|
|
if (copy_from_user(&uf, arg, sizeof(uf)))
|
|
return -EFAULT;
|
|
|
|
if (!uf.count) {
|
|
/* Disabled */
|
|
filter->count = 0;
|
|
return 0;
|
|
}
|
|
|
|
alen = ETH_ALEN * uf.count;
|
|
addr = kmalloc(alen, GFP_KERNEL);
|
|
if (!addr)
|
|
return -ENOMEM;
|
|
|
|
if (copy_from_user(addr, arg + sizeof(uf), alen)) {
|
|
err = -EFAULT;
|
|
goto done;
|
|
}
|
|
|
|
/* The filter is updated without holding any locks. Which is
|
|
* perfectly safe. We disable it first and in the worst
|
|
* case we'll accept a few undesired packets. */
|
|
filter->count = 0;
|
|
wmb();
|
|
|
|
/* Use first set of addresses as an exact filter */
|
|
for (n = 0; n < uf.count && n < FLT_EXACT_COUNT; n++)
|
|
memcpy(filter->addr[n], addr[n].u, ETH_ALEN);
|
|
|
|
nexact = n;
|
|
|
|
/* Remaining multicast addresses are hashed,
|
|
* unicast will leave the filter disabled. */
|
|
memset(filter->mask, 0, sizeof(filter->mask));
|
|
for (; n < uf.count; n++) {
|
|
if (!is_multicast_ether_addr(addr[n].u)) {
|
|
err = 0; /* no filter */
|
|
goto done;
|
|
}
|
|
addr_hash_set(filter->mask, addr[n].u);
|
|
}
|
|
|
|
/* For ALLMULTI just set the mask to all ones.
|
|
* This overrides the mask populated above. */
|
|
if ((uf.flags & TUN_FLT_ALLMULTI))
|
|
memset(filter->mask, ~0, sizeof(filter->mask));
|
|
|
|
/* Now enable the filter */
|
|
wmb();
|
|
filter->count = nexact;
|
|
|
|
/* Return the number of exact filters */
|
|
err = nexact;
|
|
|
|
done:
|
|
kfree(addr);
|
|
return err;
|
|
}
|
|
|
|
/* Returns: 0 - drop, !=0 - accept */
|
|
static int run_filter(struct tap_filter *filter, const struct sk_buff *skb)
|
|
{
|
|
/* Cannot use eth_hdr(skb) here because skb_mac_hdr() is incorrect
|
|
* at this point. */
|
|
struct ethhdr *eh = (struct ethhdr *) skb->data;
|
|
int i;
|
|
|
|
/* Exact match */
|
|
for (i = 0; i < filter->count; i++)
|
|
if (ether_addr_equal(eh->h_dest, filter->addr[i]))
|
|
return 1;
|
|
|
|
/* Inexact match (multicast only) */
|
|
if (is_multicast_ether_addr(eh->h_dest))
|
|
return addr_hash_test(filter->mask, eh->h_dest);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Checks whether the packet is accepted or not.
|
|
* Returns: 0 - drop, !=0 - accept
|
|
*/
|
|
static int check_filter(struct tap_filter *filter, const struct sk_buff *skb)
|
|
{
|
|
if (!filter->count)
|
|
return 1;
|
|
|
|
return run_filter(filter, skb);
|
|
}
|
|
|
|
/* Network device part of the driver */
|
|
|
|
static const struct ethtool_ops tun_ethtool_ops;
|
|
|
|
/* Net device detach from fd. */
|
|
static void tun_net_uninit(struct net_device *dev)
|
|
{
|
|
tun_detach_all(dev);
|
|
}
|
|
|
|
/* Net device open. */
|
|
static int tun_net_open(struct net_device *dev)
|
|
{
|
|
netif_tx_start_all_queues(dev);
|
|
return 0;
|
|
}
|
|
|
|
/* Net device close. */
|
|
static int tun_net_close(struct net_device *dev)
|
|
{
|
|
netif_tx_stop_all_queues(dev);
|
|
return 0;
|
|
}
|
|
|
|
/* Net device start xmit */
|
|
static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
int txq = skb->queue_mapping;
|
|
struct tun_file *tfile;
|
|
u32 numqueues = 0;
|
|
|
|
rcu_read_lock();
|
|
tfile = rcu_dereference(tun->tfiles[txq]);
|
|
numqueues = ACCESS_ONCE(tun->numqueues);
|
|
|
|
/* Drop packet if interface is not attached */
|
|
if (txq >= numqueues)
|
|
goto drop;
|
|
|
|
#ifdef CONFIG_RPS
|
|
if (numqueues == 1 && static_key_false(&rps_needed)) {
|
|
/* Select queue was not called for the skbuff, so we extract the
|
|
* RPS hash and save it into the flow_table here.
|
|
*/
|
|
__u32 rxhash;
|
|
|
|
rxhash = skb_get_hash(skb);
|
|
if (rxhash) {
|
|
struct tun_flow_entry *e;
|
|
e = tun_flow_find(&tun->flows[tun_hashfn(rxhash)],
|
|
rxhash);
|
|
if (e)
|
|
tun_flow_save_rps_rxhash(e, rxhash);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len);
|
|
|
|
BUG_ON(!tfile);
|
|
|
|
/* Drop if the filter does not like it.
|
|
* This is a noop if the filter is disabled.
|
|
* Filter can be enabled only for the TAP devices. */
|
|
if (!check_filter(&tun->txflt, skb))
|
|
goto drop;
|
|
|
|
if (tfile->socket.sk->sk_filter &&
|
|
sk_filter(tfile->socket.sk, skb))
|
|
goto drop;
|
|
|
|
/* Limit the number of packets queued by dividing txq length with the
|
|
* number of queues.
|
|
*/
|
|
if (skb_queue_len(&tfile->socket.sk->sk_receive_queue) * numqueues
|
|
>= dev->tx_queue_len)
|
|
goto drop;
|
|
|
|
if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
|
|
goto drop;
|
|
|
|
if (skb->sk && sk_fullsock(skb->sk)) {
|
|
sock_tx_timestamp(skb->sk, skb->sk->sk_tsflags,
|
|
&skb_shinfo(skb)->tx_flags);
|
|
sw_tx_timestamp(skb);
|
|
}
|
|
|
|
/* Orphan the skb - required as we might hang on to it
|
|
* for indefinite time.
|
|
*/
|
|
skb_orphan(skb);
|
|
|
|
nf_reset(skb);
|
|
|
|
if (skb_array_produce(&tfile->tx_array, skb))
|
|
goto drop;
|
|
|
|
/* Notify and wake up reader process */
|
|
if (tfile->flags & TUN_FASYNC)
|
|
kill_fasync(&tfile->fasync, SIGIO, POLL_IN);
|
|
tfile->socket.sk->sk_data_ready(tfile->socket.sk);
|
|
|
|
rcu_read_unlock();
|
|
return NETDEV_TX_OK;
|
|
|
|
drop:
|
|
this_cpu_inc(tun->pcpu_stats->tx_dropped);
|
|
skb_tx_error(skb);
|
|
kfree_skb(skb);
|
|
rcu_read_unlock();
|
|
return NET_XMIT_DROP;
|
|
}
|
|
|
|
static void tun_net_mclist(struct net_device *dev)
|
|
{
|
|
/*
|
|
* This callback is supposed to deal with mc filter in
|
|
* _rx_ path and has nothing to do with the _tx_ path.
|
|
* In rx path we always accept everything userspace gives us.
|
|
*/
|
|
}
|
|
|
|
#define MIN_MTU 68
|
|
#define MAX_MTU 65535
|
|
|
|
static int
|
|
tun_net_change_mtu(struct net_device *dev, int new_mtu)
|
|
{
|
|
if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU)
|
|
return -EINVAL;
|
|
dev->mtu = new_mtu;
|
|
return 0;
|
|
}
|
|
|
|
static netdev_features_t tun_net_fix_features(struct net_device *dev,
|
|
netdev_features_t features)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
|
|
return (features & tun->set_features) | (features & ~TUN_USER_FEATURES);
|
|
}
|
|
#ifdef CONFIG_NET_POLL_CONTROLLER
|
|
static void tun_poll_controller(struct net_device *dev)
|
|
{
|
|
/*
|
|
* Tun only receives frames when:
|
|
* 1) the char device endpoint gets data from user space
|
|
* 2) the tun socket gets a sendmsg call from user space
|
|
* Since both of those are synchronous operations, we are guaranteed
|
|
* never to have pending data when we poll for it
|
|
* so there is nothing to do here but return.
|
|
* We need this though so netpoll recognizes us as an interface that
|
|
* supports polling, which enables bridge devices in virt setups to
|
|
* still use netconsole
|
|
*/
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
static void tun_set_headroom(struct net_device *dev, int new_hr)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
|
|
if (new_hr < NET_SKB_PAD)
|
|
new_hr = NET_SKB_PAD;
|
|
|
|
tun->align = new_hr;
|
|
}
|
|
|
|
static struct rtnl_link_stats64 *
|
|
tun_net_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
|
|
{
|
|
u32 rx_dropped = 0, tx_dropped = 0, rx_frame_errors = 0;
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
struct tun_pcpu_stats *p;
|
|
int i;
|
|
|
|
for_each_possible_cpu(i) {
|
|
u64 rxpackets, rxbytes, txpackets, txbytes;
|
|
unsigned int start;
|
|
|
|
p = per_cpu_ptr(tun->pcpu_stats, i);
|
|
do {
|
|
start = u64_stats_fetch_begin(&p->syncp);
|
|
rxpackets = p->rx_packets;
|
|
rxbytes = p->rx_bytes;
|
|
txpackets = p->tx_packets;
|
|
txbytes = p->tx_bytes;
|
|
} while (u64_stats_fetch_retry(&p->syncp, start));
|
|
|
|
stats->rx_packets += rxpackets;
|
|
stats->rx_bytes += rxbytes;
|
|
stats->tx_packets += txpackets;
|
|
stats->tx_bytes += txbytes;
|
|
|
|
/* u32 counters */
|
|
rx_dropped += p->rx_dropped;
|
|
rx_frame_errors += p->rx_frame_errors;
|
|
tx_dropped += p->tx_dropped;
|
|
}
|
|
stats->rx_dropped = rx_dropped;
|
|
stats->rx_frame_errors = rx_frame_errors;
|
|
stats->tx_dropped = tx_dropped;
|
|
return stats;
|
|
}
|
|
|
|
static const struct net_device_ops tun_netdev_ops = {
|
|
.ndo_uninit = tun_net_uninit,
|
|
.ndo_open = tun_net_open,
|
|
.ndo_stop = tun_net_close,
|
|
.ndo_start_xmit = tun_net_xmit,
|
|
.ndo_change_mtu = tun_net_change_mtu,
|
|
.ndo_fix_features = tun_net_fix_features,
|
|
.ndo_select_queue = tun_select_queue,
|
|
#ifdef CONFIG_NET_POLL_CONTROLLER
|
|
.ndo_poll_controller = tun_poll_controller,
|
|
#endif
|
|
.ndo_set_rx_headroom = tun_set_headroom,
|
|
.ndo_get_stats64 = tun_net_get_stats64,
|
|
};
|
|
|
|
static const struct net_device_ops tap_netdev_ops = {
|
|
.ndo_uninit = tun_net_uninit,
|
|
.ndo_open = tun_net_open,
|
|
.ndo_stop = tun_net_close,
|
|
.ndo_start_xmit = tun_net_xmit,
|
|
.ndo_change_mtu = tun_net_change_mtu,
|
|
.ndo_fix_features = tun_net_fix_features,
|
|
.ndo_set_rx_mode = tun_net_mclist,
|
|
.ndo_set_mac_address = eth_mac_addr,
|
|
.ndo_validate_addr = eth_validate_addr,
|
|
.ndo_select_queue = tun_select_queue,
|
|
#ifdef CONFIG_NET_POLL_CONTROLLER
|
|
.ndo_poll_controller = tun_poll_controller,
|
|
#endif
|
|
.ndo_features_check = passthru_features_check,
|
|
.ndo_set_rx_headroom = tun_set_headroom,
|
|
.ndo_get_stats64 = tun_net_get_stats64,
|
|
};
|
|
|
|
static void tun_flow_init(struct tun_struct *tun)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++)
|
|
INIT_HLIST_HEAD(&tun->flows[i]);
|
|
|
|
tun->ageing_time = TUN_FLOW_EXPIRE;
|
|
setup_timer(&tun->flow_gc_timer, tun_flow_cleanup, (unsigned long)tun);
|
|
mod_timer(&tun->flow_gc_timer,
|
|
round_jiffies_up(jiffies + tun->ageing_time));
|
|
}
|
|
|
|
static void tun_flow_uninit(struct tun_struct *tun)
|
|
{
|
|
del_timer_sync(&tun->flow_gc_timer);
|
|
tun_flow_flush(tun);
|
|
}
|
|
|
|
/* Initialize net device. */
|
|
static void tun_net_init(struct net_device *dev)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
|
|
switch (tun->flags & TUN_TYPE_MASK) {
|
|
case IFF_TUN:
|
|
dev->netdev_ops = &tun_netdev_ops;
|
|
|
|
/* Point-to-Point TUN Device */
|
|
dev->hard_header_len = 0;
|
|
dev->addr_len = 0;
|
|
dev->mtu = 1500;
|
|
|
|
/* Zero header length */
|
|
dev->type = ARPHRD_NONE;
|
|
dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST;
|
|
break;
|
|
|
|
case IFF_TAP:
|
|
dev->netdev_ops = &tap_netdev_ops;
|
|
/* Ethernet TAP Device */
|
|
ether_setup(dev);
|
|
dev->priv_flags &= ~IFF_TX_SKB_SHARING;
|
|
dev->priv_flags |= IFF_LIVE_ADDR_CHANGE;
|
|
|
|
eth_hw_addr_random(dev);
|
|
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Character device part */
|
|
|
|
/* Poll */
|
|
static unsigned int tun_chr_poll(struct file *file, poll_table *wait)
|
|
{
|
|
struct tun_file *tfile = file->private_data;
|
|
struct tun_struct *tun = __tun_get(tfile);
|
|
struct sock *sk;
|
|
unsigned int mask = 0;
|
|
|
|
if (!tun)
|
|
return POLLERR;
|
|
|
|
sk = tfile->socket.sk;
|
|
|
|
tun_debug(KERN_INFO, tun, "tun_chr_poll\n");
|
|
|
|
poll_wait(file, sk_sleep(sk), wait);
|
|
|
|
if (!skb_array_empty(&tfile->tx_array))
|
|
mask |= POLLIN | POLLRDNORM;
|
|
|
|
if (sock_writeable(sk) ||
|
|
(!test_and_set_bit(SOCKWQ_ASYNC_NOSPACE, &sk->sk_socket->flags) &&
|
|
sock_writeable(sk)))
|
|
mask |= POLLOUT | POLLWRNORM;
|
|
|
|
if (tun->dev->reg_state != NETREG_REGISTERED)
|
|
mask = POLLERR;
|
|
|
|
tun_put(tun);
|
|
return mask;
|
|
}
|
|
|
|
/* prepad is the amount to reserve at front. len is length after that.
|
|
* linear is a hint as to how much to copy (usually headers). */
|
|
static struct sk_buff *tun_alloc_skb(struct tun_file *tfile,
|
|
size_t prepad, size_t len,
|
|
size_t linear, int noblock)
|
|
{
|
|
struct sock *sk = tfile->socket.sk;
|
|
struct sk_buff *skb;
|
|
int err;
|
|
|
|
/* Under a page? Don't bother with paged skb. */
|
|
if (prepad + len < PAGE_SIZE || !linear)
|
|
linear = len;
|
|
|
|
skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
|
|
&err, 0);
|
|
if (!skb)
|
|
return ERR_PTR(err);
|
|
|
|
skb_reserve(skb, prepad);
|
|
skb_put(skb, linear);
|
|
skb->data_len = len - linear;
|
|
skb->len += len - linear;
|
|
|
|
return skb;
|
|
}
|
|
|
|
/* Get packet from user space buffer */
|
|
static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile,
|
|
void *msg_control, struct iov_iter *from,
|
|
int noblock)
|
|
{
|
|
struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) };
|
|
struct sk_buff *skb;
|
|
size_t total_len = iov_iter_count(from);
|
|
size_t len = total_len, align = tun->align, linear;
|
|
struct virtio_net_hdr gso = { 0 };
|
|
struct tun_pcpu_stats *stats;
|
|
int good_linear;
|
|
int copylen;
|
|
bool zerocopy = false;
|
|
int err;
|
|
u32 rxhash;
|
|
ssize_t n;
|
|
|
|
if (!(tun->dev->flags & IFF_UP))
|
|
return -EIO;
|
|
|
|
if (!(tun->flags & IFF_NO_PI)) {
|
|
if (len < sizeof(pi))
|
|
return -EINVAL;
|
|
len -= sizeof(pi);
|
|
|
|
n = copy_from_iter(&pi, sizeof(pi), from);
|
|
if (n != sizeof(pi))
|
|
return -EFAULT;
|
|
}
|
|
|
|
if (tun->flags & IFF_VNET_HDR) {
|
|
if (len < tun->vnet_hdr_sz)
|
|
return -EINVAL;
|
|
len -= tun->vnet_hdr_sz;
|
|
|
|
n = copy_from_iter(&gso, sizeof(gso), from);
|
|
if (n != sizeof(gso))
|
|
return -EFAULT;
|
|
|
|
if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
|
|
tun16_to_cpu(tun, gso.csum_start) + tun16_to_cpu(tun, gso.csum_offset) + 2 > tun16_to_cpu(tun, gso.hdr_len))
|
|
gso.hdr_len = cpu_to_tun16(tun, tun16_to_cpu(tun, gso.csum_start) + tun16_to_cpu(tun, gso.csum_offset) + 2);
|
|
|
|
if (tun16_to_cpu(tun, gso.hdr_len) > len)
|
|
return -EINVAL;
|
|
iov_iter_advance(from, tun->vnet_hdr_sz - sizeof(gso));
|
|
}
|
|
|
|
if ((tun->flags & TUN_TYPE_MASK) == IFF_TAP) {
|
|
align += NET_IP_ALIGN;
|
|
if (unlikely(len < ETH_HLEN ||
|
|
(gso.hdr_len && tun16_to_cpu(tun, gso.hdr_len) < ETH_HLEN)))
|
|
return -EINVAL;
|
|
}
|
|
|
|
good_linear = SKB_MAX_HEAD(align);
|
|
|
|
if (msg_control) {
|
|
struct iov_iter i = *from;
|
|
|
|
/* There are 256 bytes to be copied in skb, so there is
|
|
* enough room for skb expand head in case it is used.
|
|
* The rest of the buffer is mapped from userspace.
|
|
*/
|
|
copylen = gso.hdr_len ? tun16_to_cpu(tun, gso.hdr_len) : GOODCOPY_LEN;
|
|
if (copylen > good_linear)
|
|
copylen = good_linear;
|
|
linear = copylen;
|
|
iov_iter_advance(&i, copylen);
|
|
if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS)
|
|
zerocopy = true;
|
|
}
|
|
|
|
if (!zerocopy) {
|
|
copylen = len;
|
|
if (tun16_to_cpu(tun, gso.hdr_len) > good_linear)
|
|
linear = good_linear;
|
|
else
|
|
linear = tun16_to_cpu(tun, gso.hdr_len);
|
|
}
|
|
|
|
skb = tun_alloc_skb(tfile, align, copylen, linear, noblock);
|
|
if (IS_ERR(skb)) {
|
|
if (PTR_ERR(skb) != -EAGAIN)
|
|
this_cpu_inc(tun->pcpu_stats->rx_dropped);
|
|
return PTR_ERR(skb);
|
|
}
|
|
|
|
if (zerocopy)
|
|
err = zerocopy_sg_from_iter(skb, from);
|
|
else {
|
|
err = skb_copy_datagram_from_iter(skb, 0, from, len);
|
|
if (!err && msg_control) {
|
|
struct ubuf_info *uarg = msg_control;
|
|
uarg->callback(uarg, false);
|
|
}
|
|
}
|
|
|
|
if (err) {
|
|
this_cpu_inc(tun->pcpu_stats->rx_dropped);
|
|
kfree_skb(skb);
|
|
return -EFAULT;
|
|
}
|
|
|
|
err = virtio_net_hdr_to_skb(skb, &gso, tun_is_little_endian(tun));
|
|
if (err) {
|
|
this_cpu_inc(tun->pcpu_stats->rx_frame_errors);
|
|
kfree_skb(skb);
|
|
return -EINVAL;
|
|
}
|
|
|
|
switch (tun->flags & TUN_TYPE_MASK) {
|
|
case IFF_TUN:
|
|
if (tun->flags & IFF_NO_PI) {
|
|
switch (skb->data[0] & 0xf0) {
|
|
case 0x40:
|
|
pi.proto = htons(ETH_P_IP);
|
|
break;
|
|
case 0x60:
|
|
pi.proto = htons(ETH_P_IPV6);
|
|
break;
|
|
default:
|
|
this_cpu_inc(tun->pcpu_stats->rx_dropped);
|
|
kfree_skb(skb);
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
skb_reset_mac_header(skb);
|
|
skb->protocol = pi.proto;
|
|
skb->dev = tun->dev;
|
|
break;
|
|
case IFF_TAP:
|
|
skb->protocol = eth_type_trans(skb, tun->dev);
|
|
break;
|
|
}
|
|
|
|
/* copy skb_ubuf_info for callback when skb has no error */
|
|
if (zerocopy) {
|
|
skb_shinfo(skb)->destructor_arg = msg_control;
|
|
skb_shinfo(skb)->tx_flags |= SKBTX_DEV_ZEROCOPY;
|
|
skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
|
|
}
|
|
|
|
skb_reset_network_header(skb);
|
|
skb_probe_transport_header(skb, 0);
|
|
|
|
rxhash = skb_get_hash(skb);
|
|
netif_rx_ni(skb);
|
|
|
|
stats = get_cpu_ptr(tun->pcpu_stats);
|
|
u64_stats_update_begin(&stats->syncp);
|
|
stats->rx_packets++;
|
|
stats->rx_bytes += len;
|
|
u64_stats_update_end(&stats->syncp);
|
|
put_cpu_ptr(stats);
|
|
|
|
tun_flow_update(tun, rxhash, tfile);
|
|
return total_len;
|
|
}
|
|
|
|
static ssize_t tun_chr_write_iter(struct kiocb *iocb, struct iov_iter *from)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct tun_struct *tun = tun_get(file);
|
|
struct tun_file *tfile = file->private_data;
|
|
ssize_t result;
|
|
|
|
if (!tun)
|
|
return -EBADFD;
|
|
|
|
result = tun_get_user(tun, tfile, NULL, from, file->f_flags & O_NONBLOCK);
|
|
|
|
tun_put(tun);
|
|
return result;
|
|
}
|
|
|
|
/* Put packet to the user space buffer */
|
|
static ssize_t tun_put_user(struct tun_struct *tun,
|
|
struct tun_file *tfile,
|
|
struct sk_buff *skb,
|
|
struct iov_iter *iter)
|
|
{
|
|
struct tun_pi pi = { 0, skb->protocol };
|
|
struct tun_pcpu_stats *stats;
|
|
ssize_t total;
|
|
int vlan_offset = 0;
|
|
int vlan_hlen = 0;
|
|
int vnet_hdr_sz = 0;
|
|
|
|
if (skb_vlan_tag_present(skb))
|
|
vlan_hlen = VLAN_HLEN;
|
|
|
|
if (tun->flags & IFF_VNET_HDR)
|
|
vnet_hdr_sz = tun->vnet_hdr_sz;
|
|
|
|
total = skb->len + vlan_hlen + vnet_hdr_sz;
|
|
|
|
if (!(tun->flags & IFF_NO_PI)) {
|
|
if (iov_iter_count(iter) < sizeof(pi))
|
|
return -EINVAL;
|
|
|
|
total += sizeof(pi);
|
|
if (iov_iter_count(iter) < total) {
|
|
/* Packet will be striped */
|
|
pi.flags |= TUN_PKT_STRIP;
|
|
}
|
|
|
|
if (copy_to_iter(&pi, sizeof(pi), iter) != sizeof(pi))
|
|
return -EFAULT;
|
|
}
|
|
|
|
if (vnet_hdr_sz) {
|
|
struct virtio_net_hdr gso = { 0 }; /* no info leak */
|
|
int ret;
|
|
|
|
if (iov_iter_count(iter) < vnet_hdr_sz)
|
|
return -EINVAL;
|
|
|
|
ret = virtio_net_hdr_from_skb(skb, &gso,
|
|
tun_is_little_endian(tun));
|
|
if (ret) {
|
|
struct skb_shared_info *sinfo = skb_shinfo(skb);
|
|
pr_err("unexpected GSO type: "
|
|
"0x%x, gso_size %d, hdr_len %d\n",
|
|
sinfo->gso_type, tun16_to_cpu(tun, gso.gso_size),
|
|
tun16_to_cpu(tun, gso.hdr_len));
|
|
print_hex_dump(KERN_ERR, "tun: ",
|
|
DUMP_PREFIX_NONE,
|
|
16, 1, skb->head,
|
|
min((int)tun16_to_cpu(tun, gso.hdr_len), 64), true);
|
|
WARN_ON_ONCE(1);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (copy_to_iter(&gso, sizeof(gso), iter) != sizeof(gso))
|
|
return -EFAULT;
|
|
|
|
iov_iter_advance(iter, vnet_hdr_sz - sizeof(gso));
|
|
}
|
|
|
|
if (vlan_hlen) {
|
|
int ret;
|
|
struct {
|
|
__be16 h_vlan_proto;
|
|
__be16 h_vlan_TCI;
|
|
} veth;
|
|
|
|
veth.h_vlan_proto = skb->vlan_proto;
|
|
veth.h_vlan_TCI = htons(skb_vlan_tag_get(skb));
|
|
|
|
vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto);
|
|
|
|
ret = skb_copy_datagram_iter(skb, 0, iter, vlan_offset);
|
|
if (ret || !iov_iter_count(iter))
|
|
goto done;
|
|
|
|
ret = copy_to_iter(&veth, sizeof(veth), iter);
|
|
if (ret != sizeof(veth) || !iov_iter_count(iter))
|
|
goto done;
|
|
}
|
|
|
|
skb_copy_datagram_iter(skb, vlan_offset, iter, skb->len - vlan_offset);
|
|
|
|
done:
|
|
/* caller is in process context, */
|
|
stats = get_cpu_ptr(tun->pcpu_stats);
|
|
u64_stats_update_begin(&stats->syncp);
|
|
stats->tx_packets++;
|
|
stats->tx_bytes += skb->len + vlan_hlen;
|
|
u64_stats_update_end(&stats->syncp);
|
|
put_cpu_ptr(tun->pcpu_stats);
|
|
|
|
return total;
|
|
}
|
|
|
|
static struct sk_buff *tun_ring_recv(struct tun_file *tfile, int noblock,
|
|
int *err)
|
|
{
|
|
DECLARE_WAITQUEUE(wait, current);
|
|
struct sk_buff *skb = NULL;
|
|
int error = 0;
|
|
|
|
skb = skb_array_consume(&tfile->tx_array);
|
|
if (skb)
|
|
goto out;
|
|
if (noblock) {
|
|
error = -EAGAIN;
|
|
goto out;
|
|
}
|
|
|
|
add_wait_queue(&tfile->wq.wait, &wait);
|
|
current->state = TASK_INTERRUPTIBLE;
|
|
|
|
while (1) {
|
|
skb = skb_array_consume(&tfile->tx_array);
|
|
if (skb)
|
|
break;
|
|
if (signal_pending(current)) {
|
|
error = -ERESTARTSYS;
|
|
break;
|
|
}
|
|
if (tfile->socket.sk->sk_shutdown & RCV_SHUTDOWN) {
|
|
error = -EFAULT;
|
|
break;
|
|
}
|
|
|
|
schedule();
|
|
}
|
|
|
|
current->state = TASK_RUNNING;
|
|
remove_wait_queue(&tfile->wq.wait, &wait);
|
|
|
|
out:
|
|
*err = error;
|
|
return skb;
|
|
}
|
|
|
|
static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile,
|
|
struct iov_iter *to,
|
|
int noblock)
|
|
{
|
|
struct sk_buff *skb;
|
|
ssize_t ret;
|
|
int err;
|
|
|
|
tun_debug(KERN_INFO, tun, "tun_do_read\n");
|
|
|
|
if (!iov_iter_count(to))
|
|
return 0;
|
|
|
|
/* Read frames from ring */
|
|
skb = tun_ring_recv(tfile, noblock, &err);
|
|
if (!skb)
|
|
return err;
|
|
|
|
ret = tun_put_user(tun, tfile, skb, to);
|
|
if (unlikely(ret < 0))
|
|
kfree_skb(skb);
|
|
else
|
|
consume_skb(skb);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t tun_chr_read_iter(struct kiocb *iocb, struct iov_iter *to)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct tun_file *tfile = file->private_data;
|
|
struct tun_struct *tun = __tun_get(tfile);
|
|
ssize_t len = iov_iter_count(to), ret;
|
|
|
|
if (!tun)
|
|
return -EBADFD;
|
|
ret = tun_do_read(tun, tfile, to, file->f_flags & O_NONBLOCK);
|
|
ret = min_t(ssize_t, ret, len);
|
|
if (ret > 0)
|
|
iocb->ki_pos = ret;
|
|
tun_put(tun);
|
|
return ret;
|
|
}
|
|
|
|
static void tun_free_netdev(struct net_device *dev)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
|
|
BUG_ON(!(list_empty(&tun->disabled)));
|
|
free_percpu(tun->pcpu_stats);
|
|
tun_flow_uninit(tun);
|
|
security_tun_dev_free_security(tun->security);
|
|
free_netdev(dev);
|
|
}
|
|
|
|
static void tun_setup(struct net_device *dev)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
|
|
tun->owner = INVALID_UID;
|
|
tun->group = INVALID_GID;
|
|
|
|
dev->ethtool_ops = &tun_ethtool_ops;
|
|
dev->destructor = tun_free_netdev;
|
|
/* We prefer our own queue length */
|
|
dev->tx_queue_len = TUN_READQ_SIZE;
|
|
}
|
|
|
|
/* Trivial set of netlink ops to allow deleting tun or tap
|
|
* device with netlink.
|
|
*/
|
|
static int tun_validate(struct nlattr *tb[], struct nlattr *data[])
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
static struct rtnl_link_ops tun_link_ops __read_mostly = {
|
|
.kind = DRV_NAME,
|
|
.priv_size = sizeof(struct tun_struct),
|
|
.setup = tun_setup,
|
|
.validate = tun_validate,
|
|
};
|
|
|
|
static void tun_sock_write_space(struct sock *sk)
|
|
{
|
|
struct tun_file *tfile;
|
|
wait_queue_head_t *wqueue;
|
|
|
|
if (!sock_writeable(sk))
|
|
return;
|
|
|
|
if (!test_and_clear_bit(SOCKWQ_ASYNC_NOSPACE, &sk->sk_socket->flags))
|
|
return;
|
|
|
|
wqueue = sk_sleep(sk);
|
|
if (wqueue && waitqueue_active(wqueue))
|
|
wake_up_interruptible_sync_poll(wqueue, POLLOUT |
|
|
POLLWRNORM | POLLWRBAND);
|
|
|
|
tfile = container_of(sk, struct tun_file, sk);
|
|
kill_fasync(&tfile->fasync, SIGIO, POLL_OUT);
|
|
}
|
|
|
|
static int tun_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len)
|
|
{
|
|
int ret;
|
|
struct tun_file *tfile = container_of(sock, struct tun_file, socket);
|
|
struct tun_struct *tun = __tun_get(tfile);
|
|
|
|
if (!tun)
|
|
return -EBADFD;
|
|
|
|
ret = tun_get_user(tun, tfile, m->msg_control, &m->msg_iter,
|
|
m->msg_flags & MSG_DONTWAIT);
|
|
tun_put(tun);
|
|
return ret;
|
|
}
|
|
|
|
static int tun_recvmsg(struct socket *sock, struct msghdr *m, size_t total_len,
|
|
int flags)
|
|
{
|
|
struct tun_file *tfile = container_of(sock, struct tun_file, socket);
|
|
struct tun_struct *tun = __tun_get(tfile);
|
|
int ret;
|
|
|
|
if (!tun)
|
|
return -EBADFD;
|
|
|
|
if (flags & ~(MSG_DONTWAIT|MSG_TRUNC|MSG_ERRQUEUE)) {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
if (flags & MSG_ERRQUEUE) {
|
|
ret = sock_recv_errqueue(sock->sk, m, total_len,
|
|
SOL_PACKET, TUN_TX_TIMESTAMP);
|
|
goto out;
|
|
}
|
|
ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT);
|
|
if (ret > (ssize_t)total_len) {
|
|
m->msg_flags |= MSG_TRUNC;
|
|
ret = flags & MSG_TRUNC ? ret : total_len;
|
|
}
|
|
out:
|
|
tun_put(tun);
|
|
return ret;
|
|
}
|
|
|
|
static int tun_peek_len(struct socket *sock)
|
|
{
|
|
struct tun_file *tfile = container_of(sock, struct tun_file, socket);
|
|
struct tun_struct *tun;
|
|
int ret = 0;
|
|
|
|
tun = __tun_get(tfile);
|
|
if (!tun)
|
|
return 0;
|
|
|
|
ret = skb_array_peek_len(&tfile->tx_array);
|
|
tun_put(tun);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Ops structure to mimic raw sockets with tun */
|
|
static const struct proto_ops tun_socket_ops = {
|
|
.peek_len = tun_peek_len,
|
|
.sendmsg = tun_sendmsg,
|
|
.recvmsg = tun_recvmsg,
|
|
};
|
|
|
|
static struct proto tun_proto = {
|
|
.name = "tun",
|
|
.owner = THIS_MODULE,
|
|
.obj_size = sizeof(struct tun_file),
|
|
};
|
|
|
|
static int tun_flags(struct tun_struct *tun)
|
|
{
|
|
return tun->flags & (TUN_FEATURES | IFF_PERSIST | IFF_TUN | IFF_TAP);
|
|
}
|
|
|
|
static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(to_net_dev(dev));
|
|
return sprintf(buf, "0x%x\n", tun_flags(tun));
|
|
}
|
|
|
|
static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(to_net_dev(dev));
|
|
return uid_valid(tun->owner)?
|
|
sprintf(buf, "%u\n",
|
|
from_kuid_munged(current_user_ns(), tun->owner)):
|
|
sprintf(buf, "-1\n");
|
|
}
|
|
|
|
static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr,
|
|
char *buf)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(to_net_dev(dev));
|
|
return gid_valid(tun->group) ?
|
|
sprintf(buf, "%u\n",
|
|
from_kgid_munged(current_user_ns(), tun->group)):
|
|
sprintf(buf, "-1\n");
|
|
}
|
|
|
|
static DEVICE_ATTR(tun_flags, 0444, tun_show_flags, NULL);
|
|
static DEVICE_ATTR(owner, 0444, tun_show_owner, NULL);
|
|
static DEVICE_ATTR(group, 0444, tun_show_group, NULL);
|
|
|
|
static struct attribute *tun_dev_attrs[] = {
|
|
&dev_attr_tun_flags.attr,
|
|
&dev_attr_owner.attr,
|
|
&dev_attr_group.attr,
|
|
NULL
|
|
};
|
|
|
|
static const struct attribute_group tun_attr_group = {
|
|
.attrs = tun_dev_attrs
|
|
};
|
|
|
|
static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr)
|
|
{
|
|
struct tun_struct *tun;
|
|
struct tun_file *tfile = file->private_data;
|
|
struct net_device *dev;
|
|
int err;
|
|
|
|
if (tfile->detached)
|
|
return -EINVAL;
|
|
|
|
dev = __dev_get_by_name(net, ifr->ifr_name);
|
|
if (dev) {
|
|
if (ifr->ifr_flags & IFF_TUN_EXCL)
|
|
return -EBUSY;
|
|
if ((ifr->ifr_flags & IFF_TUN) && dev->netdev_ops == &tun_netdev_ops)
|
|
tun = netdev_priv(dev);
|
|
else if ((ifr->ifr_flags & IFF_TAP) && dev->netdev_ops == &tap_netdev_ops)
|
|
tun = netdev_priv(dev);
|
|
else
|
|
return -EINVAL;
|
|
|
|
if (!!(ifr->ifr_flags & IFF_MULTI_QUEUE) !=
|
|
!!(tun->flags & IFF_MULTI_QUEUE))
|
|
return -EINVAL;
|
|
|
|
if (tun_not_capable(tun))
|
|
return -EPERM;
|
|
err = security_tun_dev_open(tun->security);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
err = tun_attach(tun, file, ifr->ifr_flags & IFF_NOFILTER);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
if (tun->flags & IFF_MULTI_QUEUE &&
|
|
(tun->numqueues + tun->numdisabled > 1)) {
|
|
/* One or more queue has already been attached, no need
|
|
* to initialize the device again.
|
|
*/
|
|
return 0;
|
|
}
|
|
}
|
|
else {
|
|
char *name;
|
|
unsigned long flags = 0;
|
|
int queues = ifr->ifr_flags & IFF_MULTI_QUEUE ?
|
|
MAX_TAP_QUEUES : 1;
|
|
|
|
if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
|
|
return -EPERM;
|
|
err = security_tun_dev_create();
|
|
if (err < 0)
|
|
return err;
|
|
|
|
/* Set dev type */
|
|
if (ifr->ifr_flags & IFF_TUN) {
|
|
/* TUN device */
|
|
flags |= IFF_TUN;
|
|
name = "tun%d";
|
|
} else if (ifr->ifr_flags & IFF_TAP) {
|
|
/* TAP device */
|
|
flags |= IFF_TAP;
|
|
name = "tap%d";
|
|
} else
|
|
return -EINVAL;
|
|
|
|
if (*ifr->ifr_name)
|
|
name = ifr->ifr_name;
|
|
|
|
dev = alloc_netdev_mqs(sizeof(struct tun_struct), name,
|
|
NET_NAME_UNKNOWN, tun_setup, queues,
|
|
queues);
|
|
|
|
if (!dev)
|
|
return -ENOMEM;
|
|
|
|
dev_net_set(dev, net);
|
|
dev->rtnl_link_ops = &tun_link_ops;
|
|
dev->ifindex = tfile->ifindex;
|
|
dev->sysfs_groups[0] = &tun_attr_group;
|
|
|
|
tun = netdev_priv(dev);
|
|
tun->dev = dev;
|
|
tun->flags = flags;
|
|
tun->txflt.count = 0;
|
|
tun->vnet_hdr_sz = sizeof(struct virtio_net_hdr);
|
|
|
|
tun->align = NET_SKB_PAD;
|
|
tun->filter_attached = false;
|
|
tun->sndbuf = tfile->socket.sk->sk_sndbuf;
|
|
|
|
tun->pcpu_stats = netdev_alloc_pcpu_stats(struct tun_pcpu_stats);
|
|
if (!tun->pcpu_stats) {
|
|
err = -ENOMEM;
|
|
goto err_free_dev;
|
|
}
|
|
|
|
spin_lock_init(&tun->lock);
|
|
|
|
err = security_tun_dev_alloc_security(&tun->security);
|
|
if (err < 0)
|
|
goto err_free_stat;
|
|
|
|
tun_net_init(dev);
|
|
tun_flow_init(tun);
|
|
|
|
dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST |
|
|
TUN_USER_FEATURES | NETIF_F_HW_VLAN_CTAG_TX |
|
|
NETIF_F_HW_VLAN_STAG_TX;
|
|
dev->features = dev->hw_features | NETIF_F_LLTX;
|
|
dev->vlan_features = dev->features &
|
|
~(NETIF_F_HW_VLAN_CTAG_TX |
|
|
NETIF_F_HW_VLAN_STAG_TX);
|
|
|
|
INIT_LIST_HEAD(&tun->disabled);
|
|
err = tun_attach(tun, file, false);
|
|
if (err < 0)
|
|
goto err_free_flow;
|
|
|
|
err = register_netdevice(tun->dev);
|
|
if (err < 0)
|
|
goto err_detach;
|
|
}
|
|
|
|
netif_carrier_on(tun->dev);
|
|
|
|
tun_debug(KERN_INFO, tun, "tun_set_iff\n");
|
|
|
|
tun->flags = (tun->flags & ~TUN_FEATURES) |
|
|
(ifr->ifr_flags & TUN_FEATURES);
|
|
|
|
/* Make sure persistent devices do not get stuck in
|
|
* xoff state.
|
|
*/
|
|
if (netif_running(tun->dev))
|
|
netif_tx_wake_all_queues(tun->dev);
|
|
|
|
strcpy(ifr->ifr_name, tun->dev->name);
|
|
return 0;
|
|
|
|
err_detach:
|
|
tun_detach_all(dev);
|
|
err_free_flow:
|
|
tun_flow_uninit(tun);
|
|
security_tun_dev_free_security(tun->security);
|
|
err_free_stat:
|
|
free_percpu(tun->pcpu_stats);
|
|
err_free_dev:
|
|
free_netdev(dev);
|
|
return err;
|
|
}
|
|
|
|
static void tun_get_iff(struct net *net, struct tun_struct *tun,
|
|
struct ifreq *ifr)
|
|
{
|
|
tun_debug(KERN_INFO, tun, "tun_get_iff\n");
|
|
|
|
strcpy(ifr->ifr_name, tun->dev->name);
|
|
|
|
ifr->ifr_flags = tun_flags(tun);
|
|
|
|
}
|
|
|
|
/* This is like a cut-down ethtool ops, except done via tun fd so no
|
|
* privs required. */
|
|
static int set_offload(struct tun_struct *tun, unsigned long arg)
|
|
{
|
|
netdev_features_t features = 0;
|
|
|
|
if (arg & TUN_F_CSUM) {
|
|
features |= NETIF_F_HW_CSUM;
|
|
arg &= ~TUN_F_CSUM;
|
|
|
|
if (arg & (TUN_F_TSO4|TUN_F_TSO6)) {
|
|
if (arg & TUN_F_TSO_ECN) {
|
|
features |= NETIF_F_TSO_ECN;
|
|
arg &= ~TUN_F_TSO_ECN;
|
|
}
|
|
if (arg & TUN_F_TSO4)
|
|
features |= NETIF_F_TSO;
|
|
if (arg & TUN_F_TSO6)
|
|
features |= NETIF_F_TSO6;
|
|
arg &= ~(TUN_F_TSO4|TUN_F_TSO6);
|
|
}
|
|
|
|
if (arg & TUN_F_UFO) {
|
|
features |= NETIF_F_UFO;
|
|
arg &= ~TUN_F_UFO;
|
|
}
|
|
}
|
|
|
|
/* This gives the user a way to test for new features in future by
|
|
* trying to set them. */
|
|
if (arg)
|
|
return -EINVAL;
|
|
|
|
tun->set_features = features;
|
|
netdev_update_features(tun->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void tun_detach_filter(struct tun_struct *tun, int n)
|
|
{
|
|
int i;
|
|
struct tun_file *tfile;
|
|
|
|
for (i = 0; i < n; i++) {
|
|
tfile = rtnl_dereference(tun->tfiles[i]);
|
|
lock_sock(tfile->socket.sk);
|
|
sk_detach_filter(tfile->socket.sk);
|
|
release_sock(tfile->socket.sk);
|
|
}
|
|
|
|
tun->filter_attached = false;
|
|
}
|
|
|
|
static int tun_attach_filter(struct tun_struct *tun)
|
|
{
|
|
int i, ret = 0;
|
|
struct tun_file *tfile;
|
|
|
|
for (i = 0; i < tun->numqueues; i++) {
|
|
tfile = rtnl_dereference(tun->tfiles[i]);
|
|
lock_sock(tfile->socket.sk);
|
|
ret = sk_attach_filter(&tun->fprog, tfile->socket.sk);
|
|
release_sock(tfile->socket.sk);
|
|
if (ret) {
|
|
tun_detach_filter(tun, i);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
tun->filter_attached = true;
|
|
return ret;
|
|
}
|
|
|
|
static void tun_set_sndbuf(struct tun_struct *tun)
|
|
{
|
|
struct tun_file *tfile;
|
|
int i;
|
|
|
|
for (i = 0; i < tun->numqueues; i++) {
|
|
tfile = rtnl_dereference(tun->tfiles[i]);
|
|
tfile->socket.sk->sk_sndbuf = tun->sndbuf;
|
|
}
|
|
}
|
|
|
|
static int tun_set_queue(struct file *file, struct ifreq *ifr)
|
|
{
|
|
struct tun_file *tfile = file->private_data;
|
|
struct tun_struct *tun;
|
|
int ret = 0;
|
|
|
|
rtnl_lock();
|
|
|
|
if (ifr->ifr_flags & IFF_ATTACH_QUEUE) {
|
|
tun = tfile->detached;
|
|
if (!tun) {
|
|
ret = -EINVAL;
|
|
goto unlock;
|
|
}
|
|
ret = security_tun_dev_attach_queue(tun->security);
|
|
if (ret < 0)
|
|
goto unlock;
|
|
ret = tun_attach(tun, file, false);
|
|
} else if (ifr->ifr_flags & IFF_DETACH_QUEUE) {
|
|
tun = rtnl_dereference(tfile->tun);
|
|
if (!tun || !(tun->flags & IFF_MULTI_QUEUE) || tfile->detached)
|
|
ret = -EINVAL;
|
|
else
|
|
__tun_detach(tfile, false);
|
|
} else
|
|
ret = -EINVAL;
|
|
|
|
unlock:
|
|
rtnl_unlock();
|
|
return ret;
|
|
}
|
|
|
|
static long __tun_chr_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg, int ifreq_len)
|
|
{
|
|
struct tun_file *tfile = file->private_data;
|
|
struct tun_struct *tun;
|
|
void __user* argp = (void __user*)arg;
|
|
struct ifreq ifr;
|
|
kuid_t owner;
|
|
kgid_t group;
|
|
int sndbuf;
|
|
int vnet_hdr_sz;
|
|
unsigned int ifindex;
|
|
int le;
|
|
int ret;
|
|
|
|
if (cmd == TUNSETIFF || cmd == TUNSETQUEUE || _IOC_TYPE(cmd) == 0x89) {
|
|
if (copy_from_user(&ifr, argp, ifreq_len))
|
|
return -EFAULT;
|
|
} else {
|
|
memset(&ifr, 0, sizeof(ifr));
|
|
}
|
|
if (cmd == TUNGETFEATURES) {
|
|
/* Currently this just means: "what IFF flags are valid?".
|
|
* This is needed because we never checked for invalid flags on
|
|
* TUNSETIFF.
|
|
*/
|
|
return put_user(IFF_TUN | IFF_TAP | TUN_FEATURES,
|
|
(unsigned int __user*)argp);
|
|
} else if (cmd == TUNSETQUEUE)
|
|
return tun_set_queue(file, &ifr);
|
|
|
|
ret = 0;
|
|
rtnl_lock();
|
|
|
|
tun = __tun_get(tfile);
|
|
if (cmd == TUNSETIFF && !tun) {
|
|
ifr.ifr_name[IFNAMSIZ-1] = '\0';
|
|
|
|
ret = tun_set_iff(sock_net(&tfile->sk), file, &ifr);
|
|
|
|
if (ret)
|
|
goto unlock;
|
|
|
|
if (copy_to_user(argp, &ifr, ifreq_len))
|
|
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)
|
|
goto unlock;
|
|
|
|
tun_debug(KERN_INFO, tun, "tun_chr_ioctl cmd %u\n", cmd);
|
|
|
|
ret = 0;
|
|
switch (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;
|
|
|
|
case TUNSETNOCSUM:
|
|
/* Disable/Enable checksum */
|
|
|
|
/* [unimplemented] */
|
|
tun_debug(KERN_INFO, tun, "ignored: set checksum %s\n",
|
|
arg ? "disabled" : "enabled");
|
|
break;
|
|
|
|
case TUNSETPERSIST:
|
|
/* Disable/Enable persist mode. Keep an extra reference to the
|
|
* module to prevent the module being unprobed.
|
|
*/
|
|
if (arg && !(tun->flags & IFF_PERSIST)) {
|
|
tun->flags |= IFF_PERSIST;
|
|
__module_get(THIS_MODULE);
|
|
}
|
|
if (!arg && (tun->flags & IFF_PERSIST)) {
|
|
tun->flags &= ~IFF_PERSIST;
|
|
module_put(THIS_MODULE);
|
|
}
|
|
|
|
tun_debug(KERN_INFO, tun, "persist %s\n",
|
|
arg ? "enabled" : "disabled");
|
|
break;
|
|
|
|
case TUNSETOWNER:
|
|
/* Set owner of the device */
|
|
owner = make_kuid(current_user_ns(), arg);
|
|
if (!uid_valid(owner)) {
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
tun->owner = owner;
|
|
tun_debug(KERN_INFO, tun, "owner set to %u\n",
|
|
from_kuid(&init_user_ns, tun->owner));
|
|
break;
|
|
|
|
case TUNSETGROUP:
|
|
/* Set group of the device */
|
|
group = make_kgid(current_user_ns(), arg);
|
|
if (!gid_valid(group)) {
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
tun->group = group;
|
|
tun_debug(KERN_INFO, tun, "group set to %u\n",
|
|
from_kgid(&init_user_ns, tun->group));
|
|
break;
|
|
|
|
case TUNSETLINK:
|
|
/* Only allow setting the type when the interface is down */
|
|
if (tun->dev->flags & IFF_UP) {
|
|
tun_debug(KERN_INFO, tun,
|
|
"Linktype set failed because interface is up\n");
|
|
ret = -EBUSY;
|
|
} else {
|
|
tun->dev->type = (int) arg;
|
|
tun_debug(KERN_INFO, tun, "linktype set to %d\n",
|
|
tun->dev->type);
|
|
ret = 0;
|
|
}
|
|
break;
|
|
|
|
#ifdef TUN_DEBUG
|
|
case TUNSETDEBUG:
|
|
tun->debug = arg;
|
|
break;
|
|
#endif
|
|
case TUNSETOFFLOAD:
|
|
ret = set_offload(tun, arg);
|
|
break;
|
|
|
|
case TUNSETTXFILTER:
|
|
/* Can be set only for TAPs */
|
|
ret = -EINVAL;
|
|
if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP)
|
|
break;
|
|
ret = update_filter(&tun->txflt, (void __user *)arg);
|
|
break;
|
|
|
|
case SIOCGIFHWADDR:
|
|
/* Get hw address */
|
|
memcpy(ifr.ifr_hwaddr.sa_data, tun->dev->dev_addr, ETH_ALEN);
|
|
ifr.ifr_hwaddr.sa_family = tun->dev->type;
|
|
if (copy_to_user(argp, &ifr, ifreq_len))
|
|
ret = -EFAULT;
|
|
break;
|
|
|
|
case SIOCSIFHWADDR:
|
|
/* Set hw address */
|
|
tun_debug(KERN_DEBUG, tun, "set hw address: %pM\n",
|
|
ifr.ifr_hwaddr.sa_data);
|
|
|
|
ret = dev_set_mac_address(tun->dev, &ifr.ifr_hwaddr);
|
|
break;
|
|
|
|
case TUNGETSNDBUF:
|
|
sndbuf = tfile->socket.sk->sk_sndbuf;
|
|
if (copy_to_user(argp, &sndbuf, sizeof(sndbuf)))
|
|
ret = -EFAULT;
|
|
break;
|
|
|
|
case TUNSETSNDBUF:
|
|
if (copy_from_user(&sndbuf, argp, sizeof(sndbuf))) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
|
|
tun->sndbuf = sndbuf;
|
|
tun_set_sndbuf(tun);
|
|
break;
|
|
|
|
case TUNGETVNETHDRSZ:
|
|
vnet_hdr_sz = tun->vnet_hdr_sz;
|
|
if (copy_to_user(argp, &vnet_hdr_sz, sizeof(vnet_hdr_sz)))
|
|
ret = -EFAULT;
|
|
break;
|
|
|
|
case TUNSETVNETHDRSZ:
|
|
if (copy_from_user(&vnet_hdr_sz, argp, sizeof(vnet_hdr_sz))) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
if (vnet_hdr_sz < (int)sizeof(struct virtio_net_hdr)) {
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
tun->vnet_hdr_sz = vnet_hdr_sz;
|
|
break;
|
|
|
|
case TUNGETVNETLE:
|
|
le = !!(tun->flags & TUN_VNET_LE);
|
|
if (put_user(le, (int __user *)argp))
|
|
ret = -EFAULT;
|
|
break;
|
|
|
|
case TUNSETVNETLE:
|
|
if (get_user(le, (int __user *)argp)) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
if (le)
|
|
tun->flags |= TUN_VNET_LE;
|
|
else
|
|
tun->flags &= ~TUN_VNET_LE;
|
|
break;
|
|
|
|
case TUNGETVNETBE:
|
|
ret = tun_get_vnet_be(tun, argp);
|
|
break;
|
|
|
|
case TUNSETVNETBE:
|
|
ret = tun_set_vnet_be(tun, argp);
|
|
break;
|
|
|
|
case TUNATTACHFILTER:
|
|
/* Can be set only for TAPs */
|
|
ret = -EINVAL;
|
|
if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP)
|
|
break;
|
|
ret = -EFAULT;
|
|
if (copy_from_user(&tun->fprog, argp, sizeof(tun->fprog)))
|
|
break;
|
|
|
|
ret = tun_attach_filter(tun);
|
|
break;
|
|
|
|
case TUNDETACHFILTER:
|
|
/* Can be set only for TAPs */
|
|
ret = -EINVAL;
|
|
if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP)
|
|
break;
|
|
ret = 0;
|
|
tun_detach_filter(tun, tun->numqueues);
|
|
break;
|
|
|
|
case TUNGETFILTER:
|
|
ret = -EINVAL;
|
|
if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP)
|
|
break;
|
|
ret = -EFAULT;
|
|
if (copy_to_user(argp, &tun->fprog, sizeof(tun->fprog)))
|
|
break;
|
|
ret = 0;
|
|
break;
|
|
|
|
default:
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
unlock:
|
|
rtnl_unlock();
|
|
if (tun)
|
|
tun_put(tun);
|
|
return ret;
|
|
}
|
|
|
|
static long tun_chr_ioctl(struct file *file,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
return __tun_chr_ioctl(file, cmd, arg, sizeof (struct ifreq));
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
static long tun_chr_compat_ioctl(struct file *file,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
switch (cmd) {
|
|
case TUNSETIFF:
|
|
case TUNGETIFF:
|
|
case TUNSETTXFILTER:
|
|
case TUNGETSNDBUF:
|
|
case TUNSETSNDBUF:
|
|
case SIOCGIFHWADDR:
|
|
case SIOCSIFHWADDR:
|
|
arg = (unsigned long)compat_ptr(arg);
|
|
break;
|
|
default:
|
|
arg = (compat_ulong_t)arg;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* compat_ifreq is shorter than ifreq, so we must not access beyond
|
|
* the end of that structure. All fields that are used in this
|
|
* driver are compatible though, we don't need to convert the
|
|
* contents.
|
|
*/
|
|
return __tun_chr_ioctl(file, cmd, arg, sizeof(struct compat_ifreq));
|
|
}
|
|
#endif /* CONFIG_COMPAT */
|
|
|
|
static int tun_chr_fasync(int fd, struct file *file, int on)
|
|
{
|
|
struct tun_file *tfile = file->private_data;
|
|
int ret;
|
|
|
|
if ((ret = fasync_helper(fd, file, on, &tfile->fasync)) < 0)
|
|
goto out;
|
|
|
|
if (on) {
|
|
__f_setown(file, task_pid(current), PIDTYPE_PID, 0);
|
|
tfile->flags |= TUN_FASYNC;
|
|
} else
|
|
tfile->flags &= ~TUN_FASYNC;
|
|
ret = 0;
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
static int tun_chr_open(struct inode *inode, struct file * file)
|
|
{
|
|
struct net *net = current->nsproxy->net_ns;
|
|
struct tun_file *tfile;
|
|
|
|
DBG1(KERN_INFO, "tunX: tun_chr_open\n");
|
|
|
|
tfile = (struct tun_file *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL,
|
|
&tun_proto, 0);
|
|
if (!tfile)
|
|
return -ENOMEM;
|
|
RCU_INIT_POINTER(tfile->tun, NULL);
|
|
tfile->flags = 0;
|
|
tfile->ifindex = 0;
|
|
|
|
init_waitqueue_head(&tfile->wq.wait);
|
|
RCU_INIT_POINTER(tfile->socket.wq, &tfile->wq);
|
|
|
|
tfile->socket.file = file;
|
|
tfile->socket.ops = &tun_socket_ops;
|
|
|
|
sock_init_data(&tfile->socket, &tfile->sk);
|
|
|
|
tfile->sk.sk_write_space = tun_sock_write_space;
|
|
tfile->sk.sk_sndbuf = INT_MAX;
|
|
|
|
file->private_data = tfile;
|
|
INIT_LIST_HEAD(&tfile->next);
|
|
|
|
sock_set_flag(&tfile->sk, SOCK_ZEROCOPY);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int tun_chr_close(struct inode *inode, struct file *file)
|
|
{
|
|
struct tun_file *tfile = file->private_data;
|
|
|
|
tun_detach(tfile, true);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
static void tun_chr_show_fdinfo(struct seq_file *m, struct file *f)
|
|
{
|
|
struct tun_struct *tun;
|
|
struct ifreq ifr;
|
|
|
|
memset(&ifr, 0, sizeof(ifr));
|
|
|
|
rtnl_lock();
|
|
tun = tun_get(f);
|
|
if (tun)
|
|
tun_get_iff(current->nsproxy->net_ns, tun, &ifr);
|
|
rtnl_unlock();
|
|
|
|
if (tun)
|
|
tun_put(tun);
|
|
|
|
seq_printf(m, "iff:\t%s\n", ifr.ifr_name);
|
|
}
|
|
#endif
|
|
|
|
static const struct file_operations tun_fops = {
|
|
.owner = THIS_MODULE,
|
|
.llseek = no_llseek,
|
|
.read_iter = tun_chr_read_iter,
|
|
.write_iter = tun_chr_write_iter,
|
|
.poll = tun_chr_poll,
|
|
.unlocked_ioctl = tun_chr_ioctl,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = tun_chr_compat_ioctl,
|
|
#endif
|
|
.open = tun_chr_open,
|
|
.release = tun_chr_close,
|
|
.fasync = tun_chr_fasync,
|
|
#ifdef CONFIG_PROC_FS
|
|
.show_fdinfo = tun_chr_show_fdinfo,
|
|
#endif
|
|
};
|
|
|
|
static struct miscdevice tun_miscdev = {
|
|
.minor = TUN_MINOR,
|
|
.name = "tun",
|
|
.nodename = "net/tun",
|
|
.fops = &tun_fops,
|
|
};
|
|
|
|
/* ethtool interface */
|
|
|
|
static int tun_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
|
|
{
|
|
cmd->supported = 0;
|
|
cmd->advertising = 0;
|
|
ethtool_cmd_speed_set(cmd, SPEED_10);
|
|
cmd->duplex = DUPLEX_FULL;
|
|
cmd->port = PORT_TP;
|
|
cmd->phy_address = 0;
|
|
cmd->transceiver = XCVR_INTERNAL;
|
|
cmd->autoneg = AUTONEG_DISABLE;
|
|
cmd->maxtxpkt = 0;
|
|
cmd->maxrxpkt = 0;
|
|
return 0;
|
|
}
|
|
|
|
static void tun_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
|
|
{
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
|
|
strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
|
|
strlcpy(info->version, DRV_VERSION, sizeof(info->version));
|
|
|
|
switch (tun->flags & TUN_TYPE_MASK) {
|
|
case IFF_TUN:
|
|
strlcpy(info->bus_info, "tun", sizeof(info->bus_info));
|
|
break;
|
|
case IFF_TAP:
|
|
strlcpy(info->bus_info, "tap", sizeof(info->bus_info));
|
|
break;
|
|
}
|
|
}
|
|
|
|
static u32 tun_get_msglevel(struct net_device *dev)
|
|
{
|
|
#ifdef TUN_DEBUG
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
return tun->debug;
|
|
#else
|
|
return -EOPNOTSUPP;
|
|
#endif
|
|
}
|
|
|
|
static void tun_set_msglevel(struct net_device *dev, u32 value)
|
|
{
|
|
#ifdef TUN_DEBUG
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
tun->debug = value;
|
|
#endif
|
|
}
|
|
|
|
static const struct ethtool_ops tun_ethtool_ops = {
|
|
.get_settings = tun_get_settings,
|
|
.get_drvinfo = tun_get_drvinfo,
|
|
.get_msglevel = tun_get_msglevel,
|
|
.set_msglevel = tun_set_msglevel,
|
|
.get_link = ethtool_op_get_link,
|
|
.get_ts_info = ethtool_op_get_ts_info,
|
|
};
|
|
|
|
static int tun_queue_resize(struct tun_struct *tun)
|
|
{
|
|
struct net_device *dev = tun->dev;
|
|
struct tun_file *tfile;
|
|
struct skb_array **arrays;
|
|
int n = tun->numqueues + tun->numdisabled;
|
|
int ret, i;
|
|
|
|
arrays = kmalloc(sizeof *arrays * n, GFP_KERNEL);
|
|
if (!arrays)
|
|
return -ENOMEM;
|
|
|
|
for (i = 0; i < tun->numqueues; i++) {
|
|
tfile = rtnl_dereference(tun->tfiles[i]);
|
|
arrays[i] = &tfile->tx_array;
|
|
}
|
|
list_for_each_entry(tfile, &tun->disabled, next)
|
|
arrays[i++] = &tfile->tx_array;
|
|
|
|
ret = skb_array_resize_multiple(arrays, n,
|
|
dev->tx_queue_len, GFP_KERNEL);
|
|
|
|
kfree(arrays);
|
|
return ret;
|
|
}
|
|
|
|
static int tun_device_event(struct notifier_block *unused,
|
|
unsigned long event, void *ptr)
|
|
{
|
|
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
|
|
struct tun_struct *tun = netdev_priv(dev);
|
|
|
|
if (dev->rtnl_link_ops != &tun_link_ops)
|
|
return NOTIFY_DONE;
|
|
|
|
switch (event) {
|
|
case NETDEV_CHANGE_TX_QUEUE_LEN:
|
|
if (tun_queue_resize(tun))
|
|
return NOTIFY_BAD;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return NOTIFY_DONE;
|
|
}
|
|
|
|
static struct notifier_block tun_notifier_block __read_mostly = {
|
|
.notifier_call = tun_device_event,
|
|
};
|
|
|
|
static int __init tun_init(void)
|
|
{
|
|
int ret = 0;
|
|
|
|
pr_info("%s, %s\n", DRV_DESCRIPTION, DRV_VERSION);
|
|
pr_info("%s\n", DRV_COPYRIGHT);
|
|
|
|
ret = rtnl_link_register(&tun_link_ops);
|
|
if (ret) {
|
|
pr_err("Can't register link_ops\n");
|
|
goto err_linkops;
|
|
}
|
|
|
|
ret = misc_register(&tun_miscdev);
|
|
if (ret) {
|
|
pr_err("Can't register misc device %d\n", TUN_MINOR);
|
|
goto err_misc;
|
|
}
|
|
|
|
register_netdevice_notifier(&tun_notifier_block);
|
|
return 0;
|
|
err_misc:
|
|
rtnl_link_unregister(&tun_link_ops);
|
|
err_linkops:
|
|
return ret;
|
|
}
|
|
|
|
static void tun_cleanup(void)
|
|
{
|
|
misc_deregister(&tun_miscdev);
|
|
rtnl_link_unregister(&tun_link_ops);
|
|
unregister_netdevice_notifier(&tun_notifier_block);
|
|
}
|
|
|
|
/* Get an underlying socket object from tun file. Returns error unless file is
|
|
* attached to a device. The returned object works like a packet socket, it
|
|
* can be used for sock_sendmsg/sock_recvmsg. The caller is responsible for
|
|
* holding a reference to the file for as long as the socket is in use. */
|
|
struct socket *tun_get_socket(struct file *file)
|
|
{
|
|
struct tun_file *tfile;
|
|
if (file->f_op != &tun_fops)
|
|
return ERR_PTR(-EINVAL);
|
|
tfile = file->private_data;
|
|
if (!tfile)
|
|
return ERR_PTR(-EBADFD);
|
|
return &tfile->socket;
|
|
}
|
|
EXPORT_SYMBOL_GPL(tun_get_socket);
|
|
|
|
module_init(tun_init);
|
|
module_exit(tun_cleanup);
|
|
MODULE_DESCRIPTION(DRV_DESCRIPTION);
|
|
MODULE_AUTHOR(DRV_COPYRIGHT);
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_MISCDEV(TUN_MINOR);
|
|
MODULE_ALIAS("devname:net/tun");
|