diff options
Diffstat (limited to 'drivers/net/tun.c')
| -rw-r--r-- | drivers/net/tun.c | 2961 |
1 files changed, 2190 insertions, 771 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 5cdcf92eb310..8192740357a0 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1,17 +1,8 @@ +// SPDX-License-Identifier: GPL-2.0-or-later /* * TUN - Universal TUN/TAP device driver. * Copyright (C) 1999-2002 Maxim Krasnyansky <maxk@qualcomm.com> * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * * $Id: tun.c,v 1.15 2002/03/01 02:44:24 maxk Exp $ */ @@ -44,6 +35,7 @@ #include <linux/module.h> #include <linux/errno.h> #include <linux/kernel.h> +#include <linux/sched/signal.h> #include <linux/major.h> #include <linux/slab.h> #include <linux/poll.h> @@ -60,7 +52,9 @@ #include <linux/if_arp.h> #include <linux/if_ether.h> #include <linux/if_tun.h> +#include <linux/if_vlan.h> #include <linux/crc32.h> +#include <linux/math.h> #include <linux/nsproxy.h> #include <linux/virtio_net.h> #include <linux/rcupdate.h> @@ -68,37 +62,43 @@ #include <net/netns/generic.h> #include <net/rtnetlink.h> #include <net/sock.h> +#include <net/xdp.h> +#include <net/ip_tunnels.h> +#include <linux/seq_file.h> +#include <linux/uio.h> +#include <linux/skb_array.h> +#include <linux/bpf.h> +#include <linux/bpf_trace.h> +#include <linux/mutex.h> +#include <linux/ieee802154.h> +#include <uapi/linux/if_ltalk.h> +#include <uapi/linux/if_fddi.h> +#include <uapi/linux/if_hippi.h> +#include <uapi/linux/if_fc.h> +#include <net/ax25.h> +#include <net/rose.h> +#include <net/6lowpan.h> +#include <net/rps.h> + +#include <linux/uaccess.h> +#include <linux/proc_fs.h> + +#include "tun_vnet.h" + +static void tun_default_link_ksettings(struct net_device *dev, + struct ethtool_link_ksettings *cmd); + +#define TUN_RX_PAD (NET_IP_ALIGN + NET_SKB_PAD) + +/* TUN device flags */ + +/* IFF_ATTACH_QUEUE is never stored in device flags, + * overload it to mean fasync when stored there. + */ +#define TUN_FASYNC IFF_ATTACH_QUEUE -#include <asm/uaccess.h> - -/* Uncomment to enable debugging */ -/* #define TUN_DEBUG 1 */ - -#ifdef TUN_DEBUG -static int debug; - -#define tun_debug(level, tun, fmt, args...) \ -do { \ - if (tun->debug) \ - netdev_printk(level, tun->dev, fmt, ##args); \ -} while (0) -#define DBG1(level, fmt, args...) \ -do { \ - if (debug == 2) \ - printk(level fmt, ##args); \ -} while (0) -#else -#define tun_debug(level, tun, fmt, args...) \ -do { \ - if (0) \ - netdev_printk(level, tun->dev, fmt, ##args); \ -} while (0) -#define DBG1(level, fmt, args...) \ -do { \ - if (0) \ - printk(level fmt, ##args); \ -} while (0) -#endif +#define TUN_FEATURES (IFF_NO_PI | IFF_ONE_QUEUE | IFF_VNET_HDR | \ + IFF_MULTI_QUEUE | IFF_NAPI | IFF_NAPI_FRAGS) #define GOODCOPY_LEN 128 @@ -109,16 +109,15 @@ struct tap_filter { unsigned char addr[FLT_EXACT_COUNT][ETH_ALEN]; }; -/* DEFAULT_MAX_NUM_RSS_QUEUES were choosed to let the rx/tx queues allocated for - * the netdevice to be fit in one page. So we can make sure the success of - * memory allocation. TODO: increase the limit. */ -#define MAX_TAP_QUEUES DEFAULT_MAX_NUM_RSS_QUEUES +/* MAX_TAP_QUEUES 256 is chosen to allow rx/tx queues to be equal + * to max number of VCPUs in guest. */ +#define MAX_TAP_QUEUES 256 #define MAX_TAP_FLOWS 4096 #define TUN_FLOW_EXPIRE (3 * HZ) /* A tun_file connects an open character device to a tuntap netdevice. It - * also contains all socket related strctures (except sock_fprog and tap_filter) + * also contains all socket related structures (except sock_fprog and tap_filter) * to serve as one transmit queue for tuntap device. The sock_fprog and * tap_filter were kept in tun_struct since they were used for filtering for the * netdevice not for a specific queue (at least I didn't see the requirement for @@ -131,15 +130,27 @@ struct tap_filter { struct tun_file { struct sock sk; struct socket socket; - struct socket_wq wq; struct tun_struct __rcu *tun; - struct net *net; struct fasync_struct *fasync; /* only used for fasnyc */ unsigned int flags; - u16 queue_index; + union { + u16 queue_index; + unsigned int ifindex; + }; + struct napi_struct napi; + bool napi_enabled; + bool napi_frags_enabled; + struct mutex napi_mutex; /* Protects access to the above napi */ struct list_head next; struct tun_struct *detached; + struct ptr_ring tx_ring; + struct xdp_rxq_info xdp_rxq; +}; + +struct tun_page { + struct page *page; + int count; }; struct tun_flow_entry { @@ -148,11 +159,18 @@ struct tun_flow_entry { struct tun_struct *tun; u32 rxhash; + u32 rps_rxhash; int queue_index; - unsigned long updated; + unsigned long updated ____cacheline_aligned_in_smp; }; #define TUN_NUM_FLOW_ENTRIES 1024 +#define TUN_MASK_FLOW_ENTRIES (TUN_NUM_FLOW_ENTRIES - 1) + +struct tun_prog { + struct rcu_head rcu; + struct bpf_prog *prog; +}; /* Since the socket were moved to tun_file, to preserve the behavior of persist * device, socket filter, sndbuf and vnet header size were restore when the @@ -168,17 +186,17 @@ struct tun_struct { struct net_device *dev; netdev_features_t set_features; #define TUN_USER_FEATURES (NETIF_F_HW_CSUM|NETIF_F_TSO_ECN|NETIF_F_TSO| \ - NETIF_F_TSO6|NETIF_F_UFO) + NETIF_F_TSO6 | NETIF_F_GSO_UDP_L4 | \ + NETIF_F_GSO_UDP_TUNNEL | NETIF_F_GSO_UDP_TUNNEL_CSUM) + int align; int vnet_hdr_sz; int sndbuf; struct tap_filter txflt; struct sock_fprog fprog; /* protected by rtnl lock */ bool filter_attached; -#ifdef TUN_DEBUG - int debug; -#endif + u32 msg_enable; spinlock_t lock; struct hlist_head flows[TUN_NUM_FLOW_ENTRIES]; struct timer_list flow_gc_timer; @@ -187,11 +205,102 @@ struct tun_struct { struct list_head disabled; void *security; u32 flow_count; + u32 rx_batched; + atomic_long_t rx_frame_errors; + struct bpf_prog __rcu *xdp_prog; + struct tun_prog __rcu *steering_prog; + struct tun_prog __rcu *filter_prog; + struct ethtool_link_ksettings link_ksettings; + /* init args */ + struct file *file; + struct ifreq *ifr; }; +struct veth { + __be16 h_vlan_proto; + __be16 h_vlan_TCI; +}; + +static void tun_flow_init(struct tun_struct *tun); +static void tun_flow_uninit(struct tun_struct *tun); + +static int tun_napi_receive(struct napi_struct *napi, int budget) +{ + struct tun_file *tfile = container_of(napi, struct tun_file, napi); + struct sk_buff_head *queue = &tfile->sk.sk_write_queue; + struct sk_buff_head process_queue; + struct sk_buff *skb; + int received = 0; + + __skb_queue_head_init(&process_queue); + + spin_lock(&queue->lock); + skb_queue_splice_tail_init(queue, &process_queue); + spin_unlock(&queue->lock); + + while (received < budget && (skb = __skb_dequeue(&process_queue))) { + napi_gro_receive(napi, skb); + ++received; + } + + if (!skb_queue_empty(&process_queue)) { + spin_lock(&queue->lock); + skb_queue_splice(&process_queue, queue); + spin_unlock(&queue->lock); + } + + return received; +} + +static int tun_napi_poll(struct napi_struct *napi, int budget) +{ + unsigned int received; + + received = tun_napi_receive(napi, budget); + + if (received < budget) + napi_complete_done(napi, received); + + return received; +} + +static void tun_napi_init(struct tun_struct *tun, struct tun_file *tfile, + bool napi_en, bool napi_frags) +{ + tfile->napi_enabled = napi_en; + tfile->napi_frags_enabled = napi_en && napi_frags; + if (napi_en) { + netif_napi_add_tx(tun->dev, &tfile->napi, tun_napi_poll); + napi_enable(&tfile->napi); + } +} + +static void tun_napi_enable(struct tun_file *tfile) +{ + if (tfile->napi_enabled) + napi_enable(&tfile->napi); +} + +static void tun_napi_disable(struct tun_file *tfile) +{ + if (tfile->napi_enabled) + napi_disable(&tfile->napi); +} + +static void tun_napi_del(struct tun_file *tfile) +{ + if (tfile->napi_enabled) + netif_napi_del(&tfile->napi); +} + +static bool tun_napi_frags_enabled(const struct tun_file *tfile) +{ + return tfile->napi_frags_enabled; +} + static inline u32 tun_hashfn(u32 rxhash) { - return rxhash & 0x3ff; + return rxhash & TUN_MASK_FLOW_ENTRIES; } static struct tun_flow_entry *tun_flow_find(struct hlist_head *head, u32 rxhash) @@ -212,10 +321,12 @@ static struct tun_flow_entry *tun_flow_create(struct tun_struct *tun, struct tun_flow_entry *e = kmalloc(sizeof(*e), GFP_ATOMIC); if (e) { - tun_debug(KERN_INFO, tun, "create flow: hash %u index %u\n", - rxhash, queue_index); + netif_info(tun, tx_queued, tun->dev, + "create flow: hash %u index %u\n", + rxhash, queue_index); e->updated = jiffies; e->rxhash = rxhash; + e->rps_rxhash = 0; e->queue_index = queue_index; e->tun = tun; hlist_add_head_rcu(&e->hash_link, head); @@ -226,8 +337,8 @@ static struct tun_flow_entry *tun_flow_create(struct tun_struct *tun, static void tun_flow_delete(struct tun_struct *tun, struct tun_flow_entry *e) { - tun_debug(KERN_INFO, tun, "delete flow: hash %u index %u\n", - e->rxhash, e->queue_index); + netif_info(tun, tx_queued, tun->dev, "delete flow: hash %u index %u\n", + e->rxhash, e->queue_index); hlist_del_rcu(&e->hash_link); kfree_rcu(e, rcu); --tun->flow_count; @@ -265,35 +376,36 @@ static void tun_flow_delete_by_queue(struct tun_struct *tun, u16 queue_index) spin_unlock_bh(&tun->lock); } -static void tun_flow_cleanup(unsigned long data) +static void tun_flow_cleanup(struct timer_list *t) { - struct tun_struct *tun = (struct tun_struct *)data; + struct tun_struct *tun = timer_container_of(tun, t, flow_gc_timer); unsigned long delay = tun->ageing_time; unsigned long next_timer = jiffies + delay; unsigned long count = 0; int i; - tun_debug(KERN_INFO, tun, "tun_flow_cleanup\n"); - - spin_lock_bh(&tun->lock); + spin_lock(&tun->lock); for (i = 0; i < TUN_NUM_FLOW_ENTRIES; i++) { struct tun_flow_entry *e; struct hlist_node *n; hlist_for_each_entry_safe(e, n, &tun->flows[i], hash_link) { unsigned long this_timer; - count++; + this_timer = e->updated + delay; - if (time_before_eq(this_timer, jiffies)) + if (time_before_eq(this_timer, jiffies)) { tun_flow_delete(tun, e); - else if (time_before(this_timer, next_timer)) + continue; + } + count++; + if (time_before(this_timer, next_timer)) next_timer = this_timer; } } if (count) mod_timer(&tun->flow_gc_timer, round_jiffies_up(next_timer)); - spin_unlock_bh(&tun->lock); + spin_unlock(&tun->lock); } static void tun_flow_update(struct tun_struct *tun, u32 rxhash, @@ -304,23 +416,18 @@ static void tun_flow_update(struct tun_struct *tun, u32 rxhash, unsigned long delay = tun->ageing_time; u16 queue_index = tfile->queue_index; - if (!rxhash) - return; - else - head = &tun->flows[tun_hashfn(rxhash)]; + 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; + if (READ_ONCE(e->queue_index) != queue_index) + WRITE_ONCE(e->queue_index, queue_index); + if (e->updated != jiffies) + e->updated = jiffies; + sock_rps_record_flow_hash(e->rps_rxhash); } else { spin_lock_bh(&tun->lock); if (!tun_flow_find(head, rxhash) && @@ -333,52 +440,83 @@ static void tun_flow_update(struct tun_struct *tun, u32 rxhash, spin_unlock_bh(&tun->lock); } -unlock: rcu_read_unlock(); } -/* We try to identify a flow through its rxhash first. The reason that - * we do not check rxq no. is becuase some cards(e.g 82599), chooses +/* 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. 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. + * different rxq no. here. */ -static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb) +static u16 tun_automq_select_queue(struct tun_struct *tun, struct sk_buff *skb) { - struct tun_struct *tun = netdev_priv(dev); struct tun_flow_entry *e; - u32 txq = 0; - u32 numqueues = 0; + u32 txq, numqueues; - rcu_read_lock(); - numqueues = ACCESS_ONCE(tun->numqueues); + numqueues = READ_ONCE(tun->numqueues); - txq = skb_get_rxhash(skb); - if (txq) { - e = tun_flow_find(&tun->flows[tun_hashfn(txq)], txq); - if (e) - 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; + txq = __skb_get_hash_symmetric(skb); + e = tun_flow_find(&tun->flows[tun_hashfn(txq)], txq); + if (e) { + tun_flow_save_rps_rxhash(e, txq); + txq = e->queue_index; + } else { + txq = reciprocal_scale(txq, numqueues); } - rcu_read_unlock(); return txq; } +static u16 tun_ebpf_select_queue(struct tun_struct *tun, struct sk_buff *skb) +{ + struct tun_prog *prog; + u32 numqueues; + u16 ret = 0; + + numqueues = READ_ONCE(tun->numqueues); + if (!numqueues) + return 0; + + prog = rcu_dereference(tun->steering_prog); + if (prog) + ret = bpf_prog_run_clear_cb(prog->prog, skb); + + return ret % numqueues; +} + +static u16 tun_select_queue(struct net_device *dev, struct sk_buff *skb, + struct net_device *sb_dev) +{ + struct tun_struct *tun = netdev_priv(dev); + u16 ret; + + rcu_read_lock(); + if (rcu_dereference(tun->steering_prog)) + ret = tun_ebpf_select_queue(tun, skb); + else + ret = tun_automq_select_queue(tun, skb); + rcu_read_unlock(); + + return ret; +} + 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))) && + (gid_valid(tun->group) && !in_egroup_p(tun->group))) && !ns_capable(net->user_ns, CAP_NET_ADMIN); } @@ -405,6 +543,31 @@ static struct tun_struct *tun_enable_queue(struct tun_file *tfile) return tun; } +void tun_ptr_free(void *ptr) +{ + if (!ptr) + return; + if (tun_is_xdp_frame(ptr)) { + struct xdp_frame *xdpf = tun_ptr_to_xdp(ptr); + + xdp_return_frame(xdpf); + } else { + __skb_array_destroy_skb(ptr); + } +} +EXPORT_SYMBOL_GPL(tun_ptr_free); + +static void tun_queue_purge(struct tun_file *tfile) +{ + void *ptr; + + while ((ptr = ptr_ring_consume(&tfile->tx_ring)) != NULL) + tun_ptr_free(ptr); + + skb_queue_purge(&tfile->sk.sk_write_queue); + skb_queue_purge(&tfile->sk.sk_error_queue); +} + static void __tun_detach(struct tun_file *tfile, bool clean) { struct tun_file *ntfile; @@ -412,6 +575,12 @@ static void __tun_detach(struct tun_file *tfile, bool clean) tun = rtnl_dereference(tfile->tun); + if (tun && clean) { + if (!tfile->detached) + tun_napi_disable(tfile); + tun_napi_del(tfile); + } + if (tun && !tfile->detached) { u16 index = tfile->queue_index; BUG_ON(index >= tun->numqueues); @@ -420,18 +589,23 @@ static void __tun_detach(struct tun_file *tfile, bool clean) tun->tfiles[tun->numqueues - 1]); ntfile = rtnl_dereference(tun->tfiles[index]); ntfile->queue_index = index; + ntfile->xdp_rxq.queue_index = index; + rcu_assign_pointer(tun->tfiles[tun->numqueues - 1], + NULL); --tun->numqueues; if (clean) { - rcu_assign_pointer(tfile->tun, NULL); + RCU_INIT_POINTER(tfile->tun, NULL); sock_put(&tfile->sk); - } else + } else { tun_disable_queue(tun, tfile); + tun_napi_disable(tfile); + } synchronize_net(); tun_flow_delete_by_queue(tun, tun->numqueues + 1); /* Drop read queue */ - skb_queue_purge(&tfile->sk.sk_receive_queue); + tun_queue_purge(tfile); tun_set_real_num_queues(tun); } else if (tfile->detached && clean) { tun = tun_enable_queue(tfile); @@ -442,22 +616,31 @@ static void __tun_detach(struct tun_file *tfile, bool clean) if (tun && tun->numqueues == 0 && tun->numdisabled == 0) { netif_carrier_off(tun->dev); - if (!(tun->flags & TUN_PERSIST) && + if (!(tun->flags & IFF_PERSIST) && tun->dev->reg_state == NETREG_REGISTERED) unregister_netdevice(tun->dev); } - - BUG_ON(!test_bit(SOCK_EXTERNALLY_ALLOCATED, - &tfile->socket.flags)); - sk_release_kernel(&tfile->sk); + if (tun) + xdp_rxq_info_unreg(&tfile->xdp_rxq); + ptr_ring_cleanup(&tfile->tx_ring, tun_ptr_free); } } static void tun_detach(struct tun_file *tfile, bool clean) { + struct tun_struct *tun; + struct net_device *dev; + rtnl_lock(); + tun = rtnl_dereference(tfile->tun); + dev = tun ? tun->dev : NULL; __tun_detach(tfile, clean); + if (dev) + netdev_state_change(dev); rtnl_unlock(); + + if (clean) + sock_put(&tfile->sk); } static void tun_detach_all(struct net_device *dev) @@ -469,37 +652,47 @@ static void tun_detach_all(struct net_device *dev) for (i = 0; i < n; i++) { tfile = rtnl_dereference(tun->tfiles[i]); BUG_ON(!tfile); - wake_up_all(&tfile->wq.wait); - rcu_assign_pointer(tfile->tun, NULL); + tun_napi_disable(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) { - wake_up_all(&tfile->wq.wait); - rcu_assign_pointer(tfile->tun, NULL); + 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]); + tun_napi_del(tfile); /* Drop read queue */ - skb_queue_purge(&tfile->sk.sk_receive_queue); + tun_queue_purge(tfile); + xdp_rxq_info_unreg(&tfile->xdp_rxq); sock_put(&tfile->sk); } list_for_each_entry_safe(tfile, tmp, &tun->disabled, next) { + tun_napi_del(tfile); tun_enable_queue(tfile); - skb_queue_purge(&tfile->sk.sk_receive_queue); + tun_queue_purge(tfile); + xdp_rxq_info_unreg(&tfile->xdp_rxq); sock_put(&tfile->sk); } BUG_ON(tun->numdisabled != 0); - if (tun->flags & TUN_PERSIST) + if (tun->flags & IFF_PERSIST) 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, bool napi, bool napi_frags, + bool publish_tun) { 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); @@ -511,7 +704,7 @@ static int tun_attach(struct tun_struct *tun, struct file *file) goto out; err = -EBUSY; - if (!(tun->flags & TUN_TAP_MQ) && tun->numqueues == 1) + if (!(tun->flags & IFF_MULTI_QUEUE) && tun->numqueues == 1) goto out; err = -E2BIG; @@ -521,33 +714,75 @@ 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) { + /* 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 && + ptr_ring_resize(&tfile->tx_ring, dev->tx_queue_len, + GFP_KERNEL, tun_ptr_free)) { + err = -ENOMEM; + goto out; + } + tfile->queue_index = tun->numqueues; - rcu_assign_pointer(tfile->tun, tun); - rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile); - tun->numqueues++; + tfile->socket.sk->sk_shutdown &= ~RCV_SHUTDOWN; - if (tfile->detached) + if (tfile->detached) { + /* Re-attach detached tfile, updating XDP queue_index */ + WARN_ON(!xdp_rxq_info_is_reg(&tfile->xdp_rxq)); + + if (tfile->xdp_rxq.queue_index != tfile->queue_index) + tfile->xdp_rxq.queue_index = tfile->queue_index; + } else { + /* Setup XDP RX-queue info, for new tfile getting attached */ + err = xdp_rxq_info_reg(&tfile->xdp_rxq, + tun->dev, tfile->queue_index, 0); + if (err < 0) + goto out; + err = xdp_rxq_info_reg_mem_model(&tfile->xdp_rxq, + MEM_TYPE_PAGE_SHARED, NULL); + if (err < 0) { + xdp_rxq_info_unreg(&tfile->xdp_rxq); + goto out; + } + err = 0; + } + + if (tfile->detached) { tun_enable_queue(tfile); - else + tun_napi_enable(tfile); + } else { sock_hold(&tfile->sk); + tun_napi_init(tun, tfile, napi, napi_frags); + } - tun_set_real_num_queues(tun); + if (rtnl_dereference(tun->xdp_prog)) + sock_set_flag(&tfile->sk, SOCK_XDP); /* device is allowed to go away first, so no need to hold extra * refcnt. */ + /* Publish tfile->tun and tun->tfiles only after we've fully + * initialized tfile; otherwise we risk using half-initialized + * object. + */ + if (publish_tun) + rcu_assign_pointer(tfile->tun, tun); + rcu_assign_pointer(tun->tfiles[tun->numqueues], tfile); + tun->numqueues++; + tun_set_real_num_queues(tun); out: return err; } -static struct tun_struct *__tun_get(struct tun_file *tfile) +static struct tun_struct *tun_get(struct tun_file *tfile) { struct tun_struct *tun; @@ -560,11 +795,6 @@ static struct tun_struct *__tun_get(struct tun_file *tfile) 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); @@ -599,14 +829,9 @@ static int update_filter(struct tap_filter *filter, void __user *arg) } 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; - } + addr = memdup_user(arg + sizeof(uf), alen); + if (IS_ERR(addr)) + return PTR_ERR(addr); /* The filter is updated without holding any locks. Which is * perfectly safe. We disable it first and in the worst @@ -626,7 +851,7 @@ static int update_filter(struct tap_filter *filter, void __user *arg) for (; n < uf.count; n++) { if (!is_multicast_ether_addr(addr[n].u)) { err = 0; /* no filter */ - goto done; + goto free_addr; } addr_hash_set(filter->mask, addr[n].u); } @@ -642,8 +867,7 @@ static int update_filter(struct tap_filter *filter, void __user *arg) /* Return the number of exact filters */ err = nexact; - -done: +free_addr: kfree(addr); return err; } @@ -684,6 +908,45 @@ static int check_filter(struct tap_filter *filter, const struct sk_buff *skb) static const struct ethtool_ops tun_ethtool_ops; +static int tun_net_init(struct net_device *dev) +{ + struct tun_struct *tun = netdev_priv(dev); + struct ifreq *ifr = tun->ifr; + int err; + + spin_lock_init(&tun->lock); + + err = security_tun_dev_alloc_security(&tun->security); + if (err < 0) + return err; + + tun_flow_init(tun); + + dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS; + 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->hw_enc_features = dev->hw_features; + dev->features = dev->hw_features; + dev->vlan_features = dev->features & + ~(NETIF_F_HW_VLAN_CTAG_TX | + NETIF_F_HW_VLAN_STAG_TX); + dev->lltx = true; + + tun->flags = (tun->flags & ~TUN_FEATURES) | + (ifr->ifr_flags & TUN_FEATURES); + + INIT_LIST_HEAD(&tun->disabled); + err = tun_attach(tun, tun->file, false, ifr->ifr_flags & IFF_NAPI, + ifr->ifr_flags & IFF_NAPI_FRAGS, false); + if (err < 0) { + tun_flow_uninit(tun); + security_tun_dev_free_security(tun->security); + return err; + } + return 0; +} + /* Net device detach from fd. */ static void tun_net_uninit(struct net_device *dev) { @@ -694,6 +957,7 @@ static void tun_net_uninit(struct net_device *dev) static int tun_net_open(struct net_device *dev) { netif_tx_start_all_queues(dev); + return 0; } @@ -705,66 +969,120 @@ static int tun_net_close(struct net_device *dev) } /* Net device start xmit */ +static void tun_automq_xmit(struct tun_struct *tun, struct sk_buff *skb) +{ +#ifdef CONFIG_RPS + if (tun->numqueues == 1 && static_branch_unlikely(&rps_needed)) { + /* Select queue was not called for the skbuff, so we extract the + * RPS hash and save it into the flow_table here. + */ + struct tun_flow_entry *e; + __u32 rxhash; + + rxhash = __skb_get_hash_symmetric(skb); + e = tun_flow_find(&tun->flows[tun_hashfn(rxhash)], rxhash); + if (e) + tun_flow_save_rps_rxhash(e, rxhash); + } +#endif +} + +static unsigned int run_ebpf_filter(struct tun_struct *tun, + struct sk_buff *skb, + int len) +{ + struct tun_prog *prog = rcu_dereference(tun->filter_prog); + + if (prog) + len = bpf_prog_run_clear_cb(prog->prog, skb); + + return len; +} + +/* Net device start xmit */ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) { + enum skb_drop_reason drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; struct tun_struct *tun = netdev_priv(dev); int txq = skb->queue_mapping; + struct netdev_queue *queue; struct tun_file *tfile; + int len = skb->len; rcu_read_lock(); tfile = rcu_dereference(tun->tfiles[txq]); /* Drop packet if interface is not attached */ - if (txq >= tun->numqueues) + if (!tfile) { + drop_reason = SKB_DROP_REASON_DEV_READY; goto drop; + } - tun_debug(KERN_INFO, tun, "tun_net_xmit %d\n", skb->len); + if (!rcu_dereference(tun->steering_prog)) + tun_automq_xmit(tun, skb); - BUG_ON(!tfile); + netif_info(tun, tx_queued, tun->dev, "%s %d\n", __func__, skb->len); /* 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)) + if (!check_filter(&tun->txflt, skb)) { + drop_reason = SKB_DROP_REASON_TAP_TXFILTER; goto drop; + } if (tfile->socket.sk->sk_filter && - sk_filter(tfile->socket.sk, skb)) + sk_filter_reason(tfile->socket.sk, skb, &drop_reason)) 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) - >= dev->tx_queue_len / tun->numqueues) + len = run_ebpf_filter(tun, skb, len); + if (len == 0) { + drop_reason = SKB_DROP_REASON_TAP_FILTER; + goto drop; + } + + if (pskb_trim(skb, len)) { + drop_reason = SKB_DROP_REASON_NOMEM; goto drop; + } - /* Orphan the skb - required as we might hang on to it - * for indefinite time. */ - if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC))) + if (unlikely(skb_orphan_frags_rx(skb, GFP_ATOMIC))) { + drop_reason = SKB_DROP_REASON_SKB_UCOPY_FAULT; goto drop; + } + + skb_tx_timestamp(skb); + + /* Orphan the skb - required as we might hang on to it + * for indefinite time. + */ skb_orphan(skb); - nf_reset(skb); + nf_reset_ct(skb); - /* Enqueue packet */ - skb_queue_tail(&tfile->socket.sk->sk_receive_queue, skb); + if (ptr_ring_produce(&tfile->tx_ring, skb)) { + drop_reason = SKB_DROP_REASON_FULL_RING; + goto drop; + } + + /* dev->lltx requires to do our own update of trans_start */ + queue = netdev_get_tx_queue(dev, txq); + txq_trans_cond_update(queue); /* Notify and wake up reader process */ if (tfile->flags & TUN_FASYNC) kill_fasync(&tfile->fasync, SIGIO, POLL_IN); - wake_up_interruptible_poll(&tfile->wq.wait, POLLIN | - POLLRDNORM | POLLRDBAND); + tfile->socket.sk->sk_data_ready(tfile->socket.sk); rcu_read_unlock(); return NETDEV_TX_OK; drop: - dev->stats.tx_dropped++; + dev_core_stats_tx_dropped_inc(dev); skb_tx_error(skb); - kfree_skb(skb); + kfree_skb_reason(skb, drop_reason); rcu_read_unlock(); - return NETDEV_TX_OK; + return NET_XMIT_DROP; } static void tun_net_mclist(struct net_device *dev) @@ -776,69 +1094,190 @@ static void tun_net_mclist(struct net_device *dev) */ } -#define MIN_MTU 68 -#define MAX_MTU 65535 +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); +} -static int -tun_net_change_mtu(struct net_device *dev, int new_mtu) +static void tun_set_headroom(struct net_device *dev, int new_hr) { - if (new_mtu < MIN_MTU || new_mtu + dev->hard_header_len > MAX_MTU) - return -EINVAL; - dev->mtu = new_mtu; - return 0; + struct tun_struct *tun = netdev_priv(dev); + + if (new_hr < NET_SKB_PAD) + new_hr = NET_SKB_PAD; + + tun->align = new_hr; } -static netdev_features_t tun_net_fix_features(struct net_device *dev, - netdev_features_t features) +static void +tun_net_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats) { struct tun_struct *tun = netdev_priv(dev); - return (features & tun->set_features) | (features & ~TUN_USER_FEATURES); + dev_get_tstats64(dev, stats); + + stats->rx_frame_errors += + (unsigned long)atomic_long_read(&tun->rx_frame_errors); } -#ifdef CONFIG_NET_POLL_CONTROLLER -static void tun_poll_controller(struct net_device *dev) + +static int tun_xdp_set(struct net_device *dev, struct bpf_prog *prog, + struct netlink_ext_ack *extack) { - /* - * 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 syncronous operations, we are guaranteed - * never to have pending data when we poll for it - * so theres 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; + struct tun_struct *tun = netdev_priv(dev); + struct tun_file *tfile; + struct bpf_prog *old_prog; + int i; + + old_prog = rtnl_dereference(tun->xdp_prog); + rcu_assign_pointer(tun->xdp_prog, prog); + if (old_prog) + bpf_prog_put(old_prog); + + for (i = 0; i < tun->numqueues; i++) { + tfile = rtnl_dereference(tun->tfiles[i]); + if (prog) + sock_set_flag(&tfile->sk, SOCK_XDP); + else + sock_reset_flag(&tfile->sk, SOCK_XDP); + } + list_for_each_entry(tfile, &tun->disabled, next) { + if (prog) + sock_set_flag(&tfile->sk, SOCK_XDP); + else + sock_reset_flag(&tfile->sk, SOCK_XDP); + } + + return 0; } -#endif + +static int tun_xdp(struct net_device *dev, struct netdev_bpf *xdp) +{ + switch (xdp->command) { + case XDP_SETUP_PROG: + return tun_xdp_set(dev, xdp->prog, xdp->extack); + default: + return -EINVAL; + } +} + +static int tun_net_change_carrier(struct net_device *dev, bool new_carrier) +{ + if (new_carrier) { + struct tun_struct *tun = netdev_priv(dev); + + if (!tun->numqueues) + return -EPERM; + + netif_carrier_on(dev); + } else { + netif_carrier_off(dev); + } + return 0; +} + static const struct net_device_ops tun_netdev_ops = { + .ndo_init = tun_net_init, .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, + .ndo_change_carrier = tun_net_change_carrier, }; +static void __tun_xdp_flush_tfile(struct tun_file *tfile) +{ + /* 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); +} + +static int tun_xdp_xmit(struct net_device *dev, int n, + struct xdp_frame **frames, u32 flags) +{ + struct tun_struct *tun = netdev_priv(dev); + struct tun_file *tfile; + u32 numqueues; + int nxmit = 0; + int i; + + if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK)) + return -EINVAL; + + rcu_read_lock(); + +resample: + numqueues = READ_ONCE(tun->numqueues); + if (!numqueues) { + rcu_read_unlock(); + return -ENXIO; /* Caller will free/return all frames */ + } + + tfile = rcu_dereference(tun->tfiles[smp_processor_id() % + numqueues]); + if (unlikely(!tfile)) + goto resample; + + spin_lock(&tfile->tx_ring.producer_lock); + for (i = 0; i < n; i++) { + struct xdp_frame *xdp = frames[i]; + /* Encode the XDP flag into lowest bit for consumer to differ + * XDP buffer from sk_buff. + */ + void *frame = tun_xdp_to_ptr(xdp); + + if (__ptr_ring_produce(&tfile->tx_ring, frame)) { + dev_core_stats_tx_dropped_inc(dev); + break; + } + nxmit++; + } + spin_unlock(&tfile->tx_ring.producer_lock); + + if (flags & XDP_XMIT_FLUSH) + __tun_xdp_flush_tfile(tfile); + + rcu_read_unlock(); + return nxmit; +} + +static int tun_xdp_tx(struct net_device *dev, struct xdp_buff *xdp) +{ + struct xdp_frame *frame = xdp_convert_buff_to_frame(xdp); + int nxmit; + + if (unlikely(!frame)) + return -EOVERFLOW; + + nxmit = tun_xdp_xmit(dev, 1, &frame, XDP_XMIT_FLUSH); + if (!nxmit) + xdp_return_frame_rx_napi(frame); + return nxmit; +} + static const struct net_device_ops tap_netdev_ops = { + .ndo_init = tun_net_init, .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_bpf = tun_xdp, + .ndo_xdp_xmit = tun_xdp_xmit, + .ndo_change_carrier = tun_net_change_carrier, }; static void tun_flow_init(struct tun_struct *tun) @@ -849,25 +1288,29 @@ static void tun_flow_init(struct tun_struct *tun) INIT_HLIST_HEAD(&tun->flows[i]); tun->ageing_time = TUN_FLOW_EXPIRE; - setup_timer(&tun->flow_gc_timer, tun_flow_cleanup, (unsigned long)tun); + timer_setup(&tun->flow_gc_timer, tun_flow_cleanup, 0); 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); + timer_delete_sync(&tun->flow_gc_timer); tun_flow_flush(tun); } +#define MIN_MTU 68 +#define MAX_MTU 65535 + /* Initialize net device. */ -static void tun_net_init(struct net_device *dev) +static void tun_net_initialize(struct net_device *dev) { struct tun_struct *tun = netdev_priv(dev); switch (tun->flags & TUN_TYPE_MASK) { - case TUN_TUN_DEV: + case IFF_TUN: dev->netdev_ops = &tun_netdev_ops; + dev->header_ops = &ip_tunnel_header_ops; /* Point-to-Point TUN Device */ dev->hard_header_len = 0; @@ -877,10 +1320,9 @@ static void tun_net_init(struct net_device *dev) /* Zero header length */ dev->type = ARPHRD_NONE; dev->flags = IFF_POINTOPOINT | IFF_NOARP | IFF_MULTICAST; - dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ break; - case TUN_TAP_DEV: + case IFF_TAP: dev->netdev_ops = &tap_netdev_ops; /* Ethernet TAP Device */ ether_setup(dev); @@ -889,45 +1331,117 @@ static void tun_net_init(struct net_device *dev) eth_hw_addr_random(dev); - dev->tx_queue_len = TUN_READQ_SIZE; /* We prefer our own queue length */ + /* Currently tun does not support XDP, only tap does. */ + dev->xdp_features = NETDEV_XDP_ACT_BASIC | + NETDEV_XDP_ACT_REDIRECT | + NETDEV_XDP_ACT_NDO_XMIT; + break; } + + dev->min_mtu = MIN_MTU; + dev->max_mtu = MAX_MTU - dev->hard_header_len; +} + +static bool tun_sock_writeable(struct tun_struct *tun, struct tun_file *tfile) +{ + struct sock *sk = tfile->socket.sk; + + return (tun->dev->flags & IFF_UP) && sock_writeable(sk); } /* Character device part */ /* Poll */ -static unsigned int tun_chr_poll(struct file *file, poll_table *wait) +static __poll_t tun_chr_poll(struct file *file, poll_table *wait) { struct tun_file *tfile = file->private_data; - struct tun_struct *tun = __tun_get(tfile); + struct tun_struct *tun = tun_get(tfile); struct sock *sk; - unsigned int mask = 0; + __poll_t mask = 0; if (!tun) - return POLLERR; + return EPOLLERR; sk = tfile->socket.sk; - tun_debug(KERN_INFO, tun, "tun_chr_poll\n"); - - poll_wait(file, &tfile->wq.wait, wait); + poll_wait(file, sk_sleep(sk), wait); - if (!skb_queue_empty(&sk->sk_receive_queue)) - mask |= POLLIN | POLLRDNORM; + if (!ptr_ring_empty(&tfile->tx_ring)) + mask |= EPOLLIN | EPOLLRDNORM; - if (sock_writeable(sk) || - (!test_and_set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags) && - sock_writeable(sk))) - mask |= POLLOUT | POLLWRNORM; + /* Make sure SOCKWQ_ASYNC_NOSPACE is set if not writable to + * guarantee EPOLLOUT to be raised by either here or + * tun_sock_write_space(). Then process could get notification + * after it writes to a down device and meets -EIO. + */ + if (tun_sock_writeable(tun, tfile) || + (!test_and_set_bit(SOCKWQ_ASYNC_NOSPACE, &sk->sk_socket->flags) && + tun_sock_writeable(tun, tfile))) + mask |= EPOLLOUT | EPOLLWRNORM; if (tun->dev->reg_state != NETREG_REGISTERED) - mask = POLLERR; + mask = EPOLLERR; tun_put(tun); return mask; } +static struct sk_buff *tun_napi_alloc_frags(struct tun_file *tfile, + size_t len, + const struct iov_iter *it) +{ + struct sk_buff *skb; + size_t linear; + int err; + int i; + + if (it->nr_segs > MAX_SKB_FRAGS + 1 || + len > (ETH_MAX_MTU - NET_SKB_PAD - NET_IP_ALIGN)) + return ERR_PTR(-EMSGSIZE); + + local_bh_disable(); + skb = napi_get_frags(&tfile->napi); + local_bh_enable(); + if (!skb) + return ERR_PTR(-ENOMEM); + + linear = iov_iter_single_seg_count(it); + err = __skb_grow(skb, linear); + if (err) + goto free; + + skb->len = len; + skb->data_len = len - linear; + skb->truesize += skb->data_len; + + for (i = 1; i < it->nr_segs; i++) { + const struct iovec *iov = iter_iov(it) + i; + size_t fragsz = iov->iov_len; + struct page *page; + void *frag; + + if (fragsz == 0 || fragsz > PAGE_SIZE) { + err = -EINVAL; + goto free; + } + frag = netdev_alloc_frag(fragsz); + if (!frag) { + err = -ENOMEM; + goto free; + } + page = virt_to_head_page(frag); + skb_fill_page_desc(skb, i - 1, page, + frag - page_address(page), fragsz); + } + + return skb; +free: + /* frees skb and all frags allocated with napi_alloc_frag() */ + napi_free_frags(&tfile->napi); + return ERR_PTR(err); +} + /* 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, @@ -939,11 +1453,13 @@ static struct sk_buff *tun_alloc_skb(struct tun_file *tfile, int err; /* Under a page? Don't bother with paged skb. */ - if (prepad + len < PAGE_SIZE || !linear) + if (prepad + len < PAGE_SIZE) linear = len; + if (len - linear > MAX_SKB_FRAGS * (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) + linear = len - MAX_SKB_FRAGS * (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER); skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock, - &err); + &err, PAGE_ALLOC_COSTLY_ORDER); if (!skb) return ERR_PTR(err); @@ -955,204 +1471,367 @@ static struct sk_buff *tun_alloc_skb(struct tun_file *tfile, return skb; } -/* set skb frags from iovec, this can move to core network code for reuse */ -static int zerocopy_sg_from_iovec(struct sk_buff *skb, const struct iovec *from, - int offset, size_t count) +static void tun_rx_batched(struct tun_struct *tun, struct tun_file *tfile, + struct sk_buff *skb, int more) { - int len = iov_length(from, count) - offset; - int copy = skb_headlen(skb); - int size, offset1 = 0; - int i = 0; + struct sk_buff_head *queue = &tfile->sk.sk_write_queue; + struct sk_buff_head process_queue; + u32 rx_batched = tun->rx_batched; + bool rcv = false; - /* Skip over from offset */ - while (count && (offset >= from->iov_len)) { - offset -= from->iov_len; - ++from; - --count; + if (!rx_batched || (!more && skb_queue_empty(queue))) { + local_bh_disable(); + skb_record_rx_queue(skb, tfile->queue_index); + netif_receive_skb(skb); + local_bh_enable(); + return; } - /* copy up to skb headlen */ - while (count && (copy > 0)) { - size = min_t(unsigned int, copy, from->iov_len - offset); - if (copy_from_user(skb->data + offset1, from->iov_base + offset, - size)) - return -EFAULT; - if (copy > size) { - ++from; - --count; - offset = 0; - } else - offset += size; - copy -= size; - offset1 += size; + spin_lock(&queue->lock); + if (!more || skb_queue_len(queue) == rx_batched) { + __skb_queue_head_init(&process_queue); + skb_queue_splice_tail_init(queue, &process_queue); + rcv = true; + } else { + __skb_queue_tail(queue, skb); } + spin_unlock(&queue->lock); - if (len == offset1) - return 0; + if (rcv) { + struct sk_buff *nskb; - while (count--) { - struct page *page[MAX_SKB_FRAGS]; - int num_pages; - unsigned long base; - unsigned long truesize; - - len = from->iov_len - offset; - if (!len) { - offset = 0; - ++from; - continue; + local_bh_disable(); + while ((nskb = __skb_dequeue(&process_queue))) { + skb_record_rx_queue(nskb, tfile->queue_index); + netif_receive_skb(nskb); } - base = (unsigned long)from->iov_base + offset; - size = ((base & ~PAGE_MASK) + len + ~PAGE_MASK) >> PAGE_SHIFT; - if (i + size > MAX_SKB_FRAGS) - return -EMSGSIZE; - num_pages = get_user_pages_fast(base, size, 0, &page[i]); - if (num_pages != size) { - int j; - - for (j = 0; j < num_pages; j++) - put_page(page[i + j]); - return -EFAULT; + skb_record_rx_queue(skb, tfile->queue_index); + netif_receive_skb(skb); + local_bh_enable(); + } +} + +static bool tun_can_build_skb(struct tun_struct *tun, struct tun_file *tfile, + int len, int noblock, bool zerocopy) +{ + if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP) + return false; + + if (tfile->socket.sk->sk_sndbuf != INT_MAX) + return false; + + if (!noblock) + return false; + + if (zerocopy) + return false; + + if (SKB_DATA_ALIGN(len + TUN_RX_PAD + XDP_PACKET_HEADROOM) + + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) > PAGE_SIZE) + return false; + + return true; +} + +static struct sk_buff *__tun_build_skb(struct tun_file *tfile, + struct page_frag *alloc_frag, char *buf, + int buflen, int len, int pad, + int metasize) +{ + struct sk_buff *skb = build_skb(buf, buflen); + + if (!skb) + return ERR_PTR(-ENOMEM); + + skb_reserve(skb, pad); + skb_put(skb, len); + if (metasize) + skb_metadata_set(skb, metasize); + skb_set_owner_w(skb, tfile->socket.sk); + + get_page(alloc_frag->page); + alloc_frag->offset += buflen; + + return skb; +} + +static int tun_xdp_act(struct tun_struct *tun, struct bpf_prog *xdp_prog, + struct xdp_buff *xdp, u32 act) +{ + int err; + + switch (act) { + case XDP_REDIRECT: + err = xdp_do_redirect(tun->dev, xdp, xdp_prog); + if (err) { + dev_core_stats_rx_dropped_inc(tun->dev); + return err; } - truesize = size * PAGE_SIZE; - skb->data_len += len; - skb->len += len; - skb->truesize += truesize; - atomic_add(truesize, &skb->sk->sk_wmem_alloc); - while (len) { - int off = base & ~PAGE_MASK; - int size = min_t(int, len, PAGE_SIZE - off); - __skb_fill_page_desc(skb, i, page[i], off, size); - skb_shinfo(skb)->nr_frags++; - /* increase sk_wmem_alloc */ - base += size; - len -= size; - i++; + dev_sw_netstats_rx_add(tun->dev, xdp->data_end - xdp->data); + break; + case XDP_TX: + err = tun_xdp_tx(tun->dev, xdp); + if (err < 0) { + dev_core_stats_rx_dropped_inc(tun->dev); + return err; } - offset = 0; - ++from; + dev_sw_netstats_rx_add(tun->dev, xdp->data_end - xdp->data); + break; + case XDP_PASS: + break; + default: + bpf_warn_invalid_xdp_action(tun->dev, xdp_prog, act); + fallthrough; + case XDP_ABORTED: + trace_xdp_exception(tun->dev, xdp_prog, act); + fallthrough; + case XDP_DROP: + dev_core_stats_rx_dropped_inc(tun->dev); + break; } - return 0; + + return act; +} + +static struct sk_buff *tun_build_skb(struct tun_struct *tun, + struct tun_file *tfile, + struct iov_iter *from, + struct virtio_net_hdr *hdr, + int len, int *skb_xdp) +{ + struct page_frag *alloc_frag = ¤t->task_frag; + struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; + struct bpf_prog *xdp_prog; + int buflen = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + char *buf; + size_t copied; + int pad = TUN_RX_PAD; + int metasize = 0; + int err = 0; + + rcu_read_lock(); + xdp_prog = rcu_dereference(tun->xdp_prog); + if (xdp_prog) + pad += XDP_PACKET_HEADROOM; + buflen += SKB_DATA_ALIGN(len + pad); + rcu_read_unlock(); + + alloc_frag->offset = ALIGN((u64)alloc_frag->offset, SMP_CACHE_BYTES); + if (unlikely(!skb_page_frag_refill(buflen, alloc_frag, GFP_KERNEL))) + return ERR_PTR(-ENOMEM); + + buf = (char *)page_address(alloc_frag->page) + alloc_frag->offset; + copied = copy_page_from_iter(alloc_frag->page, + alloc_frag->offset + pad, + len, from); + if (copied != len) + return ERR_PTR(-EFAULT); + + /* There's a small window that XDP may be set after the check + * of xdp_prog above, this should be rare and for simplicity + * we do XDP on skb in case the headroom is not enough. + */ + if (hdr->gso_type || !xdp_prog) { + *skb_xdp = 1; + return __tun_build_skb(tfile, alloc_frag, buf, buflen, len, + pad, metasize); + } + + *skb_xdp = 0; + + local_bh_disable(); + rcu_read_lock(); + bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); + xdp_prog = rcu_dereference(tun->xdp_prog); + if (xdp_prog) { + struct xdp_buff xdp; + u32 act; + + xdp_init_buff(&xdp, buflen, &tfile->xdp_rxq); + xdp_prepare_buff(&xdp, buf, pad, len, true); + + act = bpf_prog_run_xdp(xdp_prog, &xdp); + if (act == XDP_REDIRECT || act == XDP_TX) { + get_page(alloc_frag->page); + alloc_frag->offset += buflen; + } + err = tun_xdp_act(tun, xdp_prog, &xdp, act); + if (err < 0) { + if (act == XDP_REDIRECT || act == XDP_TX) + put_page(alloc_frag->page); + goto out; + } + + if (err == XDP_REDIRECT) + xdp_do_flush(); + if (err != XDP_PASS) + goto out; + + pad = xdp.data - xdp.data_hard_start; + len = xdp.data_end - xdp.data; + + /* It is known that the xdp_buff was prepared with metadata + * support, so the metasize will never be negative. + */ + metasize = xdp.data - xdp.data_meta; + } + bpf_net_ctx_clear(bpf_net_ctx); + rcu_read_unlock(); + local_bh_enable(); + + return __tun_build_skb(tfile, alloc_frag, buf, buflen, len, pad, + metasize); + +out: + bpf_net_ctx_clear(bpf_net_ctx); + rcu_read_unlock(); + local_bh_enable(); + return NULL; } /* Get packet from user space buffer */ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, - void *msg_control, const struct iovec *iv, - size_t total_len, size_t count, int noblock) + void *msg_control, struct iov_iter *from, + int noblock, bool more) { struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) }; struct sk_buff *skb; - size_t len = total_len, align = NET_SKB_PAD, linear; - struct virtio_net_hdr gso = { 0 }; - int offset = 0; + size_t total_len = iov_iter_count(from); + size_t len = total_len, align = tun->align, linear; + struct virtio_net_hdr_v1_hash_tunnel hdr; + struct virtio_net_hdr *gso; + int good_linear; int copylen; + int hdr_len = 0; bool zerocopy = false; int err; - u32 rxhash; + u32 rxhash = 0; + int skb_xdp = 1; + bool frags = tun_napi_frags_enabled(tfile); + enum skb_drop_reason drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; + netdev_features_t features = 0; + + /* + * Keep it easy and always zero the whole buffer, even if the + * tunnel-related field will be touched only when the feature + * is enabled and the hdr size id compatible. + */ + memset(&hdr, 0, sizeof(hdr)); + gso = (struct virtio_net_hdr *)&hdr; - if (!(tun->flags & TUN_NO_PI)) { - if ((len -= sizeof(pi)) > total_len) + if (!(tun->flags & IFF_NO_PI)) { + if (len < sizeof(pi)) return -EINVAL; + len -= sizeof(pi); - if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi))) + if (!copy_from_iter_full(&pi, sizeof(pi), from)) return -EFAULT; - offset += sizeof(pi); } - if (tun->flags & TUN_VNET_HDR) { - if ((len -= tun->vnet_hdr_sz) > total_len) - return -EINVAL; + if (tun->flags & IFF_VNET_HDR) { + int vnet_hdr_sz = READ_ONCE(tun->vnet_hdr_sz); - if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso))) - return -EFAULT; + features = tun_vnet_hdr_guest_features(vnet_hdr_sz); + hdr_len = __tun_vnet_hdr_get(vnet_hdr_sz, tun->flags, + features, from, gso); + if (hdr_len < 0) + return hdr_len; - if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && - gso.csum_start + gso.csum_offset + 2 > gso.hdr_len) - gso.hdr_len = gso.csum_start + gso.csum_offset + 2; - - if (gso.hdr_len > len) - return -EINVAL; - offset += tun->vnet_hdr_sz; + len -= vnet_hdr_sz; } - if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) { + if ((tun->flags & TUN_TYPE_MASK) == IFF_TAP) { align += NET_IP_ALIGN; - if (unlikely(len < ETH_HLEN || - (gso.hdr_len && gso.hdr_len < ETH_HLEN))) + if (unlikely(len < ETH_HLEN || (hdr_len && hdr_len < ETH_HLEN))) return -EINVAL; } - if (msg_control) - zerocopy = true; + good_linear = SKB_MAX_HEAD(align); - if (zerocopy) { - /* Userspace may produce vectors with count greater than - * MAX_SKB_FRAGS, so we need to linearize parts of the skb - * to let the rest of data to be fit in the frags. - */ - if (count > MAX_SKB_FRAGS) { - copylen = iov_length(iv, count - MAX_SKB_FRAGS); - if (copylen < offset) - copylen = 0; - else - copylen -= offset; - } else - copylen = 0; - /* There are 256 bytes to be copied in skb, so there is enough - * room for skb expand head in case it is used. + 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. */ - if (copylen < gso.hdr_len) - copylen = gso.hdr_len; - if (!copylen) - copylen = GOODCOPY_LEN; + copylen = min(hdr_len ? hdr_len : GOODCOPY_LEN, good_linear); linear = copylen; - } else { - copylen = len; - linear = gso.hdr_len; + iov_iter_advance(&i, copylen); + if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS) + zerocopy = true; } - skb = tun_alloc_skb(tfile, align, copylen, linear, noblock); - if (IS_ERR(skb)) { - if (PTR_ERR(skb) != -EAGAIN) - tun->dev->stats.rx_dropped++; - return PTR_ERR(skb); - } + if (!frags && tun_can_build_skb(tun, tfile, len, noblock, zerocopy)) { + /* For the packet that is not easy to be processed + * (e.g gso or jumbo packet), we will do it at after + * skb was created with generic XDP routine. + */ + skb = tun_build_skb(tun, tfile, from, gso, len, &skb_xdp); + err = PTR_ERR_OR_ZERO(skb); + if (err) + goto drop; + if (!skb) + return total_len; + } else { + if (!zerocopy) { + copylen = len; + linear = min(hdr_len, good_linear); + } - if (zerocopy) - err = zerocopy_sg_from_iovec(skb, iv, offset, count); - else - err = skb_copy_datagram_from_iovec(skb, 0, iv, offset, len); + if (frags) { + mutex_lock(&tfile->napi_mutex); + skb = tun_napi_alloc_frags(tfile, copylen, from); + /* tun_napi_alloc_frags() enforces a layout for the skb. + * If zerocopy is enabled, then this layout will be + * overwritten by zerocopy_sg_from_iter(). + */ + zerocopy = false; + } else { + if (!linear) + linear = min_t(size_t, good_linear, copylen); - if (err) { - tun->dev->stats.rx_dropped++; - kfree_skb(skb); - return -EFAULT; - } + skb = tun_alloc_skb(tfile, align, copylen, linear, + noblock); + } - if (gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { - if (!skb_partial_csum_set(skb, gso.csum_start, - gso.csum_offset)) { - tun->dev->stats.rx_frame_errors++; - kfree_skb(skb); - return -EINVAL; + err = PTR_ERR_OR_ZERO(skb); + if (err) + goto drop; + + if (zerocopy) + err = zerocopy_sg_from_iter(skb, from); + else + err = skb_copy_datagram_from_iter(skb, 0, from, len); + + if (err) { + err = -EFAULT; + drop_reason = SKB_DROP_REASON_SKB_UCOPY_FAULT; + goto drop; } } + if (tun_vnet_hdr_tnl_to_skb(tun->flags, features, skb, &hdr)) { + atomic_long_inc(&tun->rx_frame_errors); + err = -EINVAL; + goto free_skb; + } + switch (tun->flags & TUN_TYPE_MASK) { - case TUN_TUN_DEV: - if (tun->flags & TUN_NO_PI) { - switch (skb->data[0] & 0xf0) { - case 0x40: + case IFF_TUN: + if (tun->flags & IFF_NO_PI) { + u8 ip_version = skb->len ? (skb->data[0] >> 4) : 0; + + switch (ip_version) { + case 4: pi.proto = htons(ETH_P_IP); break; - case 0x60: + case 6: pi.proto = htons(ETH_P_IPV6); break; default: - tun->dev->stats.rx_dropped++; - kfree_skb(skb); - return -EINVAL; + err = -EINVAL; + goto drop; } } @@ -1160,245 +1839,423 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, skb->protocol = pi.proto; skb->dev = tun->dev; break; - case TUN_TAP_DEV: + case IFF_TAP: + if (frags && !pskb_may_pull(skb, ETH_HLEN)) { + err = -ENOMEM; + drop_reason = SKB_DROP_REASON_HDR_TRUNC; + goto drop; + } skb->protocol = eth_type_trans(skb, tun->dev); break; } - if (gso.gso_type != VIRTIO_NET_HDR_GSO_NONE) { - pr_debug("GSO!\n"); - switch (gso.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { - case VIRTIO_NET_HDR_GSO_TCPV4: - skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; - break; - case VIRTIO_NET_HDR_GSO_TCPV6: - skb_shinfo(skb)->gso_type = SKB_GSO_TCPV6; - break; - case VIRTIO_NET_HDR_GSO_UDP: - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; - break; - default: - tun->dev->stats.rx_frame_errors++; - kfree_skb(skb); - return -EINVAL; - } + /* copy skb_ubuf_info for callback when skb has no error */ + if (zerocopy) { + skb_zcopy_init(skb, msg_control); + } else if (msg_control) { + struct ubuf_info *uarg = msg_control; + uarg->ops->complete(NULL, uarg, false); + } - if (gso.gso_type & VIRTIO_NET_HDR_GSO_ECN) - skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; + skb_reset_network_header(skb); + skb_probe_transport_header(skb); + skb_record_rx_queue(skb, tfile->queue_index); + + if (skb_xdp) { + struct bpf_prog *xdp_prog; + int ret; + + local_bh_disable(); + rcu_read_lock(); + xdp_prog = rcu_dereference(tun->xdp_prog); + if (xdp_prog) { + ret = do_xdp_generic(xdp_prog, &skb); + if (ret != XDP_PASS) { + rcu_read_unlock(); + local_bh_enable(); + goto unlock_frags; + } - skb_shinfo(skb)->gso_size = gso.gso_size; - if (skb_shinfo(skb)->gso_size == 0) { - tun->dev->stats.rx_frame_errors++; - kfree_skb(skb); - return -EINVAL; + if (frags && skb != tfile->napi.skb) + tfile->napi.skb = skb; } - - /* Header must be checked, and gso_segs computed. */ - skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY; - skb_shinfo(skb)->gso_segs = 0; + rcu_read_unlock(); + local_bh_enable(); } - /* 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; + /* Compute the costly rx hash only if needed for flow updates. + * We may get a very small possibility of OOO during switching, not + * worth to optimize. + */ + if (!rcu_access_pointer(tun->steering_prog) && tun->numqueues > 1 && + !tfile->detached) + rxhash = __skb_get_hash_symmetric(skb); + + rcu_read_lock(); + if (unlikely(!(tun->dev->flags & IFF_UP))) { + err = -EIO; + rcu_read_unlock(); + drop_reason = SKB_DROP_REASON_DEV_READY; + goto drop; } - skb_reset_network_header(skb); - skb_probe_transport_header(skb, 0); + if (frags) { + u32 headlen; + + /* Exercise flow dissector code path. */ + skb_push(skb, ETH_HLEN); + headlen = eth_get_headlen(tun->dev, skb->data, + skb_headlen(skb)); + + if (unlikely(headlen > skb_headlen(skb))) { + WARN_ON_ONCE(1); + err = -ENOMEM; + dev_core_stats_rx_dropped_inc(tun->dev); +napi_busy: + napi_free_frags(&tfile->napi); + rcu_read_unlock(); + mutex_unlock(&tfile->napi_mutex); + return err; + } - rxhash = skb_get_rxhash(skb); - netif_rx_ni(skb); + if (likely(napi_schedule_prep(&tfile->napi))) { + local_bh_disable(); + napi_gro_frags(&tfile->napi); + napi_complete(&tfile->napi); + local_bh_enable(); + } else { + err = -EBUSY; + goto napi_busy; + } + mutex_unlock(&tfile->napi_mutex); + } else if (tfile->napi_enabled) { + struct sk_buff_head *queue = &tfile->sk.sk_write_queue; + int queue_len; + + spin_lock_bh(&queue->lock); + + if (unlikely(tfile->detached)) { + spin_unlock_bh(&queue->lock); + rcu_read_unlock(); + err = -EBUSY; + goto free_skb; + } + + __skb_queue_tail(queue, skb); + queue_len = skb_queue_len(queue); + spin_unlock(&queue->lock); - tun->dev->stats.rx_packets++; - tun->dev->stats.rx_bytes += len; + if (!more || queue_len > NAPI_POLL_WEIGHT) + napi_schedule(&tfile->napi); + + local_bh_enable(); + } else if (!IS_ENABLED(CONFIG_4KSTACKS)) { + tun_rx_batched(tun, tfile, skb, more); + } else { + netif_rx(skb); + } + rcu_read_unlock(); + + preempt_disable(); + dev_sw_netstats_rx_add(tun->dev, len); + preempt_enable(); + + if (rxhash) + tun_flow_update(tun, rxhash, tfile); - tun_flow_update(tun, rxhash, tfile); return total_len; + +drop: + if (err != -EAGAIN) + dev_core_stats_rx_dropped_inc(tun->dev); + +free_skb: + if (!IS_ERR_OR_NULL(skb)) + kfree_skb_reason(skb, drop_reason); + +unlock_frags: + if (frags) { + tfile->napi.skb = NULL; + mutex_unlock(&tfile->napi_mutex); + } + + return err ?: total_len; } -static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, - unsigned long count, loff_t pos) +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; + struct tun_struct *tun = tun_get(tfile); ssize_t result; + int noblock = 0; if (!tun) return -EBADFD; - tun_debug(KERN_INFO, tun, "tun_chr_write %ld\n", count); + if ((file->f_flags & O_NONBLOCK) || (iocb->ki_flags & IOCB_NOWAIT)) + noblock = 1; - result = tun_get_user(tun, tfile, NULL, iv, iov_length(iv, count), - count, file->f_flags & O_NONBLOCK); + result = tun_get_user(tun, tfile, NULL, from, noblock, false); tun_put(tun); return result; } +static ssize_t tun_put_user_xdp(struct tun_struct *tun, + struct tun_file *tfile, + struct xdp_frame *xdp_frame, + struct iov_iter *iter) +{ + int vnet_hdr_sz = 0; + size_t size = xdp_frame->len; + ssize_t ret; + + if (tun->flags & IFF_VNET_HDR) { + struct virtio_net_hdr gso = { 0 }; + + vnet_hdr_sz = READ_ONCE(tun->vnet_hdr_sz); + ret = tun_vnet_hdr_put(vnet_hdr_sz, iter, &gso); + if (ret) + return ret; + } + + ret = copy_to_iter(xdp_frame->data, size, iter) + vnet_hdr_sz; + + preempt_disable(); + dev_sw_netstats_tx_add(tun->dev, 1, ret); + preempt_enable(); + + return ret; +} + /* 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, - const struct iovec *iv, int len) + struct iov_iter *iter) { struct tun_pi pi = { 0, skb->protocol }; - ssize_t total = 0; + ssize_t total; + int vlan_offset = 0; + int vlan_hlen = 0; + int vnet_hdr_sz = 0; + int ret; + + if (skb_vlan_tag_present(skb)) + vlan_hlen = VLAN_HLEN; + + if (tun->flags & IFF_VNET_HDR) + vnet_hdr_sz = READ_ONCE(tun->vnet_hdr_sz); - if (!(tun->flags & TUN_NO_PI)) { - if ((len -= sizeof(pi)) < 0) + total = skb->len + vlan_hlen + vnet_hdr_sz; + + if (!(tun->flags & IFF_NO_PI)) { + if (iov_iter_count(iter) < sizeof(pi)) return -EINVAL; - if (len < skb->len) { + total += sizeof(pi); + if (iov_iter_count(iter) < total) { /* Packet will be striped */ pi.flags |= TUN_PKT_STRIP; } - if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi))) + if (copy_to_iter(&pi, sizeof(pi), iter) != sizeof(pi)) return -EFAULT; - total += sizeof(pi); } - if (tun->flags & TUN_VNET_HDR) { - struct virtio_net_hdr gso = { 0 }; /* no info leak */ - if ((len -= tun->vnet_hdr_sz) < 0) - return -EINVAL; + if (vnet_hdr_sz) { + struct virtio_net_hdr_v1_hash_tunnel hdr; + struct virtio_net_hdr *gso; - if (skb_is_gso(skb)) { - struct skb_shared_info *sinfo = skb_shinfo(skb); - - /* This is a hint as to how much should be linear. */ - gso.hdr_len = skb_headlen(skb); - gso.gso_size = sinfo->gso_size; - if (sinfo->gso_type & SKB_GSO_TCPV4) - gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV4; - else if (sinfo->gso_type & SKB_GSO_TCPV6) - gso.gso_type = VIRTIO_NET_HDR_GSO_TCPV6; - else if (sinfo->gso_type & SKB_GSO_UDP) - gso.gso_type = VIRTIO_NET_HDR_GSO_UDP; - else { - pr_err("unexpected GSO type: " - "0x%x, gso_size %d, hdr_len %d\n", - sinfo->gso_type, gso.gso_size, - gso.hdr_len); - print_hex_dump(KERN_ERR, "tun: ", - DUMP_PREFIX_NONE, - 16, 1, skb->head, - min((int)gso.hdr_len, 64), true); - WARN_ON_ONCE(1); - return -EINVAL; - } - if (sinfo->gso_type & SKB_GSO_TCP_ECN) - gso.gso_type |= VIRTIO_NET_HDR_GSO_ECN; - } else - gso.gso_type = VIRTIO_NET_HDR_GSO_NONE; - - if (skb->ip_summed == CHECKSUM_PARTIAL) { - gso.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; - gso.csum_start = skb_checksum_start_offset(skb); - gso.csum_offset = skb->csum_offset; - } else if (skb->ip_summed == CHECKSUM_UNNECESSARY) { - gso.flags = VIRTIO_NET_HDR_F_DATA_VALID; - } /* else everything is zero */ - - if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total, - sizeof(gso)))) - return -EFAULT; - total += tun->vnet_hdr_sz; + ret = tun_vnet_hdr_tnl_from_skb(tun->flags, tun->dev, skb, + &hdr); + if (ret) + return ret; + + /* + * Drop the packet if the configured header size is too small + * WRT the enabled offloads. + */ + gso = (struct virtio_net_hdr *)&hdr; + ret = __tun_vnet_hdr_put(vnet_hdr_sz, tun->dev->features, + iter, gso); + if (ret) + return ret; } - len = min_t(int, skb->len, len); + if (vlan_hlen) { + int ret; + struct veth 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_const_iovec(skb, 0, iv, total, len); - total += skb->len; + skb_copy_datagram_iter(skb, vlan_offset, iter, skb->len - vlan_offset); - tun->dev->stats.tx_packets++; - tun->dev->stats.tx_bytes += len; +done: + /* caller is in process context, */ + preempt_disable(); + dev_sw_netstats_tx_add(tun->dev, 1, skb->len + vlan_hlen); + preempt_enable(); return total; } -static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, - struct kiocb *iocb, const struct iovec *iv, - ssize_t len, int noblock) +static void *tun_ring_recv(struct tun_file *tfile, int noblock, int *err) { DECLARE_WAITQUEUE(wait, current); - struct sk_buff *skb; - ssize_t ret = 0; - - tun_debug(KERN_INFO, tun, "tun_do_read\n"); + void *ptr = NULL; + int error = 0; - if (unlikely(!noblock)) - add_wait_queue(&tfile->wq.wait, &wait); - while (len) { - current->state = TASK_INTERRUPTIBLE; + ptr = ptr_ring_consume(&tfile->tx_ring); + if (ptr) + goto out; + if (noblock) { + error = -EAGAIN; + goto out; + } - /* Read frames from the queue */ - if (!(skb = skb_dequeue(&tfile->socket.sk->sk_receive_queue))) { - if (noblock) { - ret = -EAGAIN; - break; - } - if (signal_pending(current)) { - ret = -ERESTARTSYS; - break; - } - if (tun->dev->reg_state != NETREG_REGISTERED) { - ret = -EIO; - break; - } + add_wait_queue(&tfile->socket.wq.wait, &wait); - /* Nothing to read, let's sleep */ - schedule(); - continue; + while (1) { + set_current_state(TASK_INTERRUPTIBLE); + ptr = ptr_ring_consume(&tfile->tx_ring); + if (ptr) + break; + if (signal_pending(current)) { + error = -ERESTARTSYS; + break; + } + if (tfile->socket.sk->sk_shutdown & RCV_SHUTDOWN) { + error = -EFAULT; + break; } - ret = tun_put_user(tun, tfile, skb, iv, len); - kfree_skb(skb); - break; + schedule(); + } + + __set_current_state(TASK_RUNNING); + remove_wait_queue(&tfile->socket.wq.wait, &wait); + +out: + *err = error; + return ptr; +} + +static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, + struct iov_iter *to, + int noblock, void *ptr) +{ + ssize_t ret; + int err; + + if (!iov_iter_count(to)) { + tun_ptr_free(ptr); + return 0; + } + + if (!ptr) { + /* Read frames from ring */ + ptr = tun_ring_recv(tfile, noblock, &err); + if (!ptr) + return err; } - current->state = TASK_RUNNING; - if (unlikely(!noblock)) - remove_wait_queue(&tfile->wq.wait, &wait); + if (tun_is_xdp_frame(ptr)) { + struct xdp_frame *xdpf = tun_ptr_to_xdp(ptr); + + ret = tun_put_user_xdp(tun, tfile, xdpf, to); + xdp_return_frame(xdpf); + } else { + struct sk_buff *skb = ptr; + + 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_aio_read(struct kiocb *iocb, const struct iovec *iv, - unsigned long count, loff_t pos) +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, ret; + struct tun_struct *tun = tun_get(tfile); + ssize_t len = iov_iter_count(to), ret; + int noblock = 0; if (!tun) return -EBADFD; - len = iov_length(iv, count); - if (len < 0) { - ret = -EINVAL; - goto out; - } - ret = tun_do_read(tun, tfile, iocb, iv, len, - file->f_flags & O_NONBLOCK); + if ((file->f_flags & O_NONBLOCK) || (iocb->ki_flags & IOCB_NOWAIT)) + noblock = 1; + + ret = tun_do_read(tun, tfile, to, noblock, NULL); ret = min_t(ssize_t, ret, len); -out: + if (ret > 0) + iocb->ki_pos = ret; tun_put(tun); return ret; } +static void tun_prog_free(struct rcu_head *rcu) +{ + struct tun_prog *prog = container_of(rcu, struct tun_prog, rcu); + + bpf_prog_destroy(prog->prog); + kfree(prog); +} + +static int __tun_set_ebpf(struct tun_struct *tun, + struct tun_prog __rcu **prog_p, + struct bpf_prog *prog) +{ + struct tun_prog *old, *new = NULL; + + if (prog) { + new = kmalloc(sizeof(*new), GFP_KERNEL); + if (!new) + return -ENOMEM; + new->prog = prog; + } + + spin_lock_bh(&tun->lock); + old = rcu_dereference_protected(*prog_p, + lockdep_is_held(&tun->lock)); + rcu_assign_pointer(*prog_p, new); + spin_unlock_bh(&tun->lock); + + if (old) + call_rcu(&old->rcu, tun_prog_free); + + return 0; +} + static void tun_free_netdev(struct net_device *dev) { struct tun_struct *tun = netdev_priv(dev); BUG_ON(!(list_empty(&tun->disabled))); + tun_flow_uninit(tun); security_tun_dev_free_security(tun->security); - free_netdev(dev); + __tun_set_ebpf(tun, &tun->steering_prog, NULL); + __tun_set_ebpf(tun, &tun->filter_prog, NULL); } static void tun_setup(struct net_device *dev) @@ -1407,17 +2264,78 @@ static void tun_setup(struct net_device *dev) tun->owner = INVALID_UID; tun->group = INVALID_GID; + tun_default_link_ksettings(dev, &tun->link_ksettings); dev->ethtool_ops = &tun_ethtool_ops; - dev->destructor = tun_free_netdev; + dev->needs_free_netdev = true; + dev->priv_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[]) +static int tun_validate(struct nlattr *tb[], struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + NL_SET_ERR_MSG(extack, + "tun/tap creation via rtnetlink is not supported."); + return -EOPNOTSUPP; +} + +static size_t tun_get_size(const struct net_device *dev) +{ + BUILD_BUG_ON(sizeof(u32) != sizeof(uid_t)); + BUILD_BUG_ON(sizeof(u32) != sizeof(gid_t)); + + return nla_total_size(sizeof(uid_t)) + /* OWNER */ + nla_total_size(sizeof(gid_t)) + /* GROUP */ + nla_total_size(sizeof(u8)) + /* TYPE */ + nla_total_size(sizeof(u8)) + /* PI */ + nla_total_size(sizeof(u8)) + /* VNET_HDR */ + nla_total_size(sizeof(u8)) + /* PERSIST */ + nla_total_size(sizeof(u8)) + /* MULTI_QUEUE */ + nla_total_size(sizeof(u32)) + /* NUM_QUEUES */ + nla_total_size(sizeof(u32)) + /* NUM_DISABLED_QUEUES */ + 0; +} + +static int tun_fill_info(struct sk_buff *skb, const struct net_device *dev) { - return -EINVAL; + struct tun_struct *tun = netdev_priv(dev); + + if (nla_put_u8(skb, IFLA_TUN_TYPE, tun->flags & TUN_TYPE_MASK)) + goto nla_put_failure; + if (uid_valid(tun->owner) && + nla_put_u32(skb, IFLA_TUN_OWNER, + from_kuid_munged(current_user_ns(), tun->owner))) + goto nla_put_failure; + if (gid_valid(tun->group) && + nla_put_u32(skb, IFLA_TUN_GROUP, + from_kgid_munged(current_user_ns(), tun->group))) + goto nla_put_failure; + if (nla_put_u8(skb, IFLA_TUN_PI, !(tun->flags & IFF_NO_PI))) + goto nla_put_failure; + if (nla_put_u8(skb, IFLA_TUN_VNET_HDR, !!(tun->flags & IFF_VNET_HDR))) + goto nla_put_failure; + if (nla_put_u8(skb, IFLA_TUN_PERSIST, !!(tun->flags & IFF_PERSIST))) + goto nla_put_failure; + if (nla_put_u8(skb, IFLA_TUN_MULTI_QUEUE, + !!(tun->flags & IFF_MULTI_QUEUE))) + goto nla_put_failure; + if (tun->flags & IFF_MULTI_QUEUE) { + if (nla_put_u32(skb, IFLA_TUN_NUM_QUEUES, tun->numqueues)) + goto nla_put_failure; + if (nla_put_u32(skb, IFLA_TUN_NUM_DISABLED_QUEUES, + tun->numdisabled)) + goto nla_put_failure; + } + + return 0; + +nla_put_failure: + return -EMSGSIZE; } static struct rtnl_link_ops tun_link_ops __read_mostly = { @@ -1425,6 +2343,8 @@ static struct rtnl_link_ops tun_link_ops __read_mostly = { .priv_size = sizeof(struct tun_struct), .setup = tun_setup, .validate = tun_validate, + .get_size = tun_get_size, + .fill_info = tun_fill_info, }; static void tun_sock_write_space(struct sock *sk) @@ -1435,72 +2355,285 @@ static void tun_sock_write_space(struct sock *sk) if (!sock_writeable(sk)) return; - if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags)) + 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); + wake_up_interruptible_sync_poll(wqueue, EPOLLOUT | + EPOLLWRNORM | EPOLLWRBAND); tfile = container_of(sk, struct tun_file, sk); kill_fasync(&tfile->fasync, SIGIO, POLL_OUT); } -static int tun_sendmsg(struct kiocb *iocb, struct socket *sock, - struct msghdr *m, size_t total_len) +static void tun_put_page(struct tun_page *tpage) { - int ret; + if (tpage->page) + __page_frag_cache_drain(tpage->page, tpage->count); +} + +static int tun_xdp_one(struct tun_struct *tun, + struct tun_file *tfile, + struct xdp_buff *xdp, int *flush, + struct tun_page *tpage) +{ + unsigned int datasize = xdp->data_end - xdp->data; + struct virtio_net_hdr *gso = xdp->data_hard_start; + struct virtio_net_hdr_v1_hash_tunnel *tnl_hdr; + struct bpf_prog *xdp_prog; + struct sk_buff *skb = NULL; + struct sk_buff_head *queue; + netdev_features_t features; + u32 rxhash = 0, act; + int buflen = xdp->frame_sz; + int metasize = 0; + int ret = 0; + bool skb_xdp = false; + struct page *page; + + if (unlikely(datasize < ETH_HLEN)) + return -EINVAL; + + xdp_prog = rcu_dereference(tun->xdp_prog); + if (xdp_prog) { + if (gso->gso_type) { + skb_xdp = true; + goto build; + } + + xdp_init_buff(xdp, buflen, &tfile->xdp_rxq); + + act = bpf_prog_run_xdp(xdp_prog, xdp); + ret = tun_xdp_act(tun, xdp_prog, xdp, act); + if (ret < 0) { + put_page(virt_to_head_page(xdp->data)); + return ret; + } + + switch (ret) { + case XDP_REDIRECT: + *flush = true; + fallthrough; + case XDP_TX: + return 0; + case XDP_PASS: + break; + default: + page = virt_to_head_page(xdp->data); + if (tpage->page == page) { + ++tpage->count; + } else { + tun_put_page(tpage); + tpage->page = page; + tpage->count = 1; + } + return 0; + } + } + +build: + skb = build_skb(xdp->data_hard_start, buflen); + if (!skb) { + ret = -ENOMEM; + goto out; + } + + skb_reserve(skb, xdp->data - xdp->data_hard_start); + skb_put(skb, xdp->data_end - xdp->data); + + /* The externally provided xdp_buff may have no metadata support, which + * is marked by xdp->data_meta being xdp->data + 1. This will lead to a + * metasize of -1 and is the reason why the condition checks for > 0. + */ + metasize = xdp->data - xdp->data_meta; + if (metasize > 0) + skb_metadata_set(skb, metasize); + + features = tun_vnet_hdr_guest_features(READ_ONCE(tun->vnet_hdr_sz)); + tnl_hdr = (struct virtio_net_hdr_v1_hash_tunnel *)gso; + if (tun_vnet_hdr_tnl_to_skb(tun->flags, features, skb, tnl_hdr)) { + atomic_long_inc(&tun->rx_frame_errors); + kfree_skb(skb); + ret = -EINVAL; + goto out; + } + + skb->protocol = eth_type_trans(skb, tun->dev); + skb_reset_network_header(skb); + skb_probe_transport_header(skb); + skb_record_rx_queue(skb, tfile->queue_index); + + if (skb_xdp) { + ret = do_xdp_generic(xdp_prog, &skb); + if (ret != XDP_PASS) { + ret = 0; + goto out; + } + } + + if (!rcu_dereference(tun->steering_prog) && tun->numqueues > 1 && + !tfile->detached) + rxhash = __skb_get_hash_symmetric(skb); + + if (tfile->napi_enabled) { + queue = &tfile->sk.sk_write_queue; + spin_lock(&queue->lock); + + if (unlikely(tfile->detached)) { + spin_unlock(&queue->lock); + kfree_skb(skb); + return -EBUSY; + } + + __skb_queue_tail(queue, skb); + spin_unlock(&queue->lock); + ret = 1; + } else { + netif_receive_skb(skb); + ret = 0; + } + + /* No need to disable preemption here since this function is + * always called with bh disabled + */ + dev_sw_netstats_rx_add(tun->dev, datasize); + + if (rxhash) + tun_flow_update(tun, rxhash, tfile); + +out: + return ret; +} + +static int tun_sendmsg(struct socket *sock, struct msghdr *m, size_t total_len) +{ + int ret, i; struct tun_file *tfile = container_of(sock, struct tun_file, socket); - struct tun_struct *tun = __tun_get(tfile); + struct tun_struct *tun = tun_get(tfile); + struct tun_msg_ctl *ctl = m->msg_control; + struct xdp_buff *xdp; if (!tun) return -EBADFD; - ret = tun_get_user(tun, tfile, m->msg_control, m->msg_iov, total_len, - m->msg_iovlen, m->msg_flags & MSG_DONTWAIT); + + if (m->msg_controllen == sizeof(struct tun_msg_ctl) && + ctl && ctl->type == TUN_MSG_PTR) { + struct bpf_net_context __bpf_net_ctx, *bpf_net_ctx; + struct tun_page tpage; + int n = ctl->num; + int flush = 0, queued = 0; + + memset(&tpage, 0, sizeof(tpage)); + + local_bh_disable(); + rcu_read_lock(); + bpf_net_ctx = bpf_net_ctx_set(&__bpf_net_ctx); + + for (i = 0; i < n; i++) { + xdp = &((struct xdp_buff *)ctl->ptr)[i]; + ret = tun_xdp_one(tun, tfile, xdp, &flush, &tpage); + if (ret > 0) + queued += ret; + } + + if (flush) + xdp_do_flush(); + + if (tfile->napi_enabled && queued > 0) + napi_schedule(&tfile->napi); + + bpf_net_ctx_clear(bpf_net_ctx); + rcu_read_unlock(); + local_bh_enable(); + + tun_put_page(&tpage); + + ret = total_len; + goto out; + } + + ret = tun_get_user(tun, tfile, ctl ? ctl->ptr : NULL, &m->msg_iter, + m->msg_flags & MSG_DONTWAIT, + m->msg_flags & MSG_MORE); +out: tun_put(tun); return ret; } - -static int tun_recvmsg(struct kiocb *iocb, struct socket *sock, - struct msghdr *m, size_t total_len, +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); + struct tun_struct *tun = tun_get(tfile); + void *ptr = m->msg_control; int ret; - if (!tun) - return -EBADFD; + if (!tun) { + ret = -EBADFD; + goto out_free; + } - if (flags & ~(MSG_DONTWAIT|MSG_TRUNC)) { + if (flags & ~(MSG_DONTWAIT|MSG_TRUNC|MSG_ERRQUEUE)) { ret = -EINVAL; + goto out_put_tun; + } + 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, iocb, m->msg_iov, total_len, - flags & MSG_DONTWAIT); - if (ret > total_len) { + ret = tun_do_read(tun, tfile, &m->msg_iter, flags & MSG_DONTWAIT, ptr); + if (ret > (ssize_t)total_len) { m->msg_flags |= MSG_TRUNC; ret = flags & MSG_TRUNC ? ret : total_len; } out: tun_put(tun); return ret; + +out_put_tun: + tun_put(tun); +out_free: + tun_ptr_free(ptr); + return ret; } -static int tun_release(struct socket *sock) +static int tun_ptr_peek_len(void *ptr) { - if (sock->sk) - sock_put(sock->sk); - return 0; + if (likely(ptr)) { + if (tun_is_xdp_frame(ptr)) { + struct xdp_frame *xdpf = tun_ptr_to_xdp(ptr); + + return xdpf->len; + } + return __skb_array_len_with_tag(ptr); + } else { + return 0; + } +} + +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 = PTR_RING_PEEK_CALL(&tfile->tx_ring, tun_ptr_peek_len); + 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, - .release = tun_release, }; static struct proto tun_proto = { @@ -1511,64 +2644,50 @@ static struct proto tun_proto = { static int tun_flags(struct tun_struct *tun) { - int flags = 0; - - if (tun->flags & TUN_TUN_DEV) - flags |= IFF_TUN; - else - flags |= IFF_TAP; - - if (tun->flags & TUN_NO_PI) - flags |= IFF_NO_PI; - - /* This flag has no real effect. We track the value for backwards - * compatibility. - */ - if (tun->flags & TUN_ONE_QUEUE) - flags |= IFF_ONE_QUEUE; - - if (tun->flags & TUN_VNET_HDR) - flags |= IFF_VNET_HDR; - - if (tun->flags & TUN_TAP_MQ) - flags |= IFF_MULTI_QUEUE; - - if (tun->flags & TUN_PERSIST) - flags |= IFF_PERSIST; - - return flags; + return tun->flags & (TUN_FEATURES | IFF_PERSIST | IFF_TUN | IFF_TAP); } -static ssize_t tun_show_flags(struct device *dev, struct device_attribute *attr, +static ssize_t tun_flags_show(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)); + return sysfs_emit(buf, "0x%x\n", tun_flags(tun)); } -static ssize_t tun_show_owner(struct device *dev, struct device_attribute *attr, - char *buf) +static ssize_t owner_show(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"); + sysfs_emit(buf, "%u\n", + from_kuid_munged(current_user_ns(), tun->owner)) : + sysfs_emit(buf, "-1\n"); } -static ssize_t tun_show_group(struct device *dev, struct device_attribute *attr, - char *buf) +static ssize_t group_show(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"); + sysfs_emit(buf, "%u\n", + from_kgid_munged(current_user_ns(), tun->group)) : + sysfs_emit(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 DEVICE_ATTR_RO(tun_flags); +static DEVICE_ATTR_RO(owner); +static DEVICE_ATTR_RO(group); + +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) { @@ -1580,6 +2699,15 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) if (tfile->detached) return -EINVAL; + if ((ifr->ifr_flags & IFF_NAPI_FRAGS)) { + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + if (!(ifr->ifr_flags & IFF_NAPI) || + (ifr->ifr_flags & TUN_TYPE_MASK) != IFF_TAP) + return -EINVAL; + } + dev = __dev_get_by_name(net, ifr->ifr_name); if (dev) { if (ifr->ifr_flags & IFF_TUN_EXCL) @@ -1592,7 +2720,7 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) return -EINVAL; if (!!(ifr->ifr_flags & IFF_MULTI_QUEUE) != - !!(tun->flags & TUN_TAP_MQ)) + !!(tun->flags & IFF_MULTI_QUEUE)) return -EINVAL; if (tun_not_capable(tun)) @@ -1601,19 +2729,26 @@ 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, + ifr->ifr_flags & IFF_NAPI, + ifr->ifr_flags & IFF_NAPI_FRAGS, true); if (err < 0) return err; - if (tun->flags & TUN_TAP_MQ && + 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. */ + netdev_state_change(dev); return 0; } - } - else { + + tun->flags = (tun->flags & ~TUN_FEATURES) | + (ifr->ifr_flags & TUN_FEATURES); + + netdev_state_change(dev); + } else { char *name; unsigned long flags = 0; int queues = ifr->ifr_flags & IFF_MULTI_QUEUE ? @@ -1628,11 +2763,11 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) /* Set dev type */ if (ifr->ifr_flags & IFF_TUN) { /* TUN device */ - flags |= TUN_TUN_DEV; + flags |= IFF_TUN; name = "tun%d"; } else if (ifr->ifr_flags & IFF_TAP) { /* TAP device */ - flags |= TUN_TAP_DEV; + flags |= IFF_TAP; name = "tap%d"; } else return -EINVAL; @@ -1641,13 +2776,16 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) name = ifr->ifr_name; dev = alloc_netdev_mqs(sizeof(struct tun_struct), name, - tun_setup, queues, queues); + 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; @@ -1655,64 +2793,32 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) 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->rx_batched = 0; + RCU_INIT_POINTER(tun->steering_prog, NULL); - spin_lock_init(&tun->lock); - - err = security_tun_dev_alloc_security(&tun->security); - if (err < 0) - goto err_free_dev; - - tun_net_init(dev); - tun_flow_init(tun); + tun->ifr = ifr; + tun->file = file; - dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | - TUN_USER_FEATURES; - dev->features = dev->hw_features; - dev->vlan_features = dev->features; - - INIT_LIST_HEAD(&tun->disabled); - err = tun_attach(tun, file); - if (err < 0) - goto err_free_dev; + tun_net_initialize(dev); err = register_netdevice(tun->dev); - if (err < 0) - goto err_free_dev; - - if (device_create_file(&tun->dev->dev, &dev_attr_tun_flags) || - device_create_file(&tun->dev->dev, &dev_attr_owner) || - device_create_file(&tun->dev->dev, &dev_attr_group)) - pr_err("Failed to create tun sysfs files\n"); + if (err < 0) { + free_netdev(dev); + return err; + } + /* free_netdev() won't check refcnt, to avoid race + * with dev_put() we need publish tun after registration. + */ + rcu_assign_pointer(tfile->tun, tun); } - netif_carrier_on(tun->dev); - - tun_debug(KERN_INFO, tun, "tun_set_iff\n"); - - if (ifr->ifr_flags & IFF_NO_PI) - tun->flags |= TUN_NO_PI; - else - tun->flags &= ~TUN_NO_PI; - - /* This flag has no real effect. We track the value for backwards - * compatibility. - */ - if (ifr->ifr_flags & IFF_ONE_QUEUE) - tun->flags |= TUN_ONE_QUEUE; - else - tun->flags &= ~TUN_ONE_QUEUE; - - if (ifr->ifr_flags & IFF_VNET_HDR) - tun->flags |= TUN_VNET_HDR; + if (ifr->ifr_flags & IFF_NO_CARRIER) + netif_carrier_off(tun->dev); else - tun->flags &= ~TUN_VNET_HDR; - - if (ifr->ifr_flags & IFF_MULTI_QUEUE) - tun->flags |= TUN_TAP_MQ; - else - tun->flags &= ~TUN_TAP_MQ; + netif_carrier_on(tun->dev); /* Make sure persistent devices do not get stuck in * xoff state. @@ -1720,25 +2826,20 @@ static int tun_set_iff(struct net *net, struct file *file, struct ifreq *ifr) if (netif_running(tun->dev)) netif_tx_wake_all_queues(tun->dev); - strcpy(ifr->ifr_name, tun->dev->name); + strscpy(ifr->ifr_name, tun->dev->name); return 0; - - err_free_dev: - free_netdev(dev); - return err; } -static void tun_get_iff(struct net *net, struct tun_struct *tun, - struct ifreq *ifr) +static void tun_get_iff(struct tun_struct *tun, struct ifreq *ifr) { - tun_debug(KERN_INFO, tun, "tun_get_iff\n"); - - strcpy(ifr->ifr_name, tun->dev->name); + strscpy(ifr->ifr_name, tun->dev->name); ifr->ifr_flags = tun_flags(tun); } +#define PLAIN_GSO (NETIF_F_GSO_UDP_L4 | NETIF_F_TSO | NETIF_F_TSO6) + /* 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) @@ -1761,9 +2862,24 @@ static int set_offload(struct tun_struct *tun, unsigned long arg) arg &= ~(TUN_F_TSO4|TUN_F_TSO6); } - if (arg & TUN_F_UFO) { - features |= NETIF_F_UFO; - arg &= ~TUN_F_UFO; + arg &= ~TUN_F_UFO; + + /* TODO: for now USO4 and USO6 should work simultaneously */ + if (arg & TUN_F_USO4 && arg & TUN_F_USO6) { + features |= NETIF_F_GSO_UDP_L4; + arg &= ~(TUN_F_USO4 | TUN_F_USO6); + } + + /* + * Tunnel offload is allowed only if some plain offload is + * available, too. + */ + if (features & PLAIN_GSO && arg & TUN_F_UDP_TUNNEL_GSO) { + features |= NETIF_F_GSO_UDP_TUNNEL; + if (arg & TUN_F_UDP_TUNNEL_GSO_CSUM) + features |= NETIF_F_GSO_UDP_TUNNEL_CSUM; + arg &= ~(TUN_F_UDP_TUNNEL_GSO | + TUN_F_UDP_TUNNEL_GSO_CSUM); } } @@ -1773,6 +2889,8 @@ static int set_offload(struct tun_struct *tun, unsigned long arg) return -EINVAL; tun->set_features = features; + tun->dev->wanted_features &= ~TUN_USER_FEATURES; + tun->dev->wanted_features |= features; netdev_update_features(tun->dev); return 0; @@ -1785,7 +2903,9 @@ static void tun_detach_filter(struct tun_struct *tun, int n) 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; @@ -1798,7 +2918,9 @@ static int tun_attach_filter(struct tun_struct *tun) 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; @@ -1837,35 +2959,102 @@ 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, tun->flags & IFF_NAPI, + tun->flags & IFF_NAPI_FRAGS, true); } else if (ifr->ifr_flags & IFF_DETACH_QUEUE) { tun = rtnl_dereference(tfile->tun); - if (!tun || !(tun->flags & TUN_TAP_MQ) || tfile->detached) + if (!tun || !(tun->flags & IFF_MULTI_QUEUE) || tfile->detached) ret = -EINVAL; else __tun_detach(tfile, false); } else ret = -EINVAL; + if (ret >= 0) + netdev_state_change(tun->dev); + unlock: rtnl_unlock(); return ret; } +static int tun_set_ebpf(struct tun_struct *tun, struct tun_prog __rcu **prog_p, + void __user *data) +{ + struct bpf_prog *prog; + int fd; + + if (copy_from_user(&fd, data, sizeof(fd))) + return -EFAULT; + + if (fd == -1) { + prog = NULL; + } else { + prog = bpf_prog_get_type(fd, BPF_PROG_TYPE_SOCKET_FILTER); + if (IS_ERR(prog)) + return PTR_ERR(prog); + } + + return __tun_set_ebpf(tun, prog_p, prog); +} + +/* Return correct value for tun->dev->addr_len based on tun->dev->type. */ +static unsigned char tun_get_addr_len(unsigned short type) +{ + switch (type) { + case ARPHRD_IP6GRE: + case ARPHRD_TUNNEL6: + return sizeof(struct in6_addr); + case ARPHRD_IPGRE: + case ARPHRD_TUNNEL: + case ARPHRD_SIT: + return 4; + case ARPHRD_ETHER: + return ETH_ALEN; + case ARPHRD_IEEE802154: + case ARPHRD_IEEE802154_MONITOR: + return IEEE802154_EXTENDED_ADDR_LEN; + case ARPHRD_PHONET_PIPE: + case ARPHRD_PPP: + case ARPHRD_NONE: + return 0; + case ARPHRD_6LOWPAN: + return EUI64_ADDR_LEN; + case ARPHRD_FDDI: + return FDDI_K_ALEN; + case ARPHRD_HIPPI: + return HIPPI_ALEN; + case ARPHRD_IEEE802: + return FC_ALEN; + case ARPHRD_ROSE: + return ROSE_ADDR_LEN; + case ARPHRD_NETROM: + return AX25_ADDR_LEN; + case ARPHRD_LOCALTLK: + return LTALK_ALEN; + default: + return 0; + } +} + 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 net *net = sock_net(&tfile->sk); struct tun_struct *tun; void __user* argp = (void __user*)arg; + unsigned int carrier; struct ifreq ifr; kuid_t owner; kgid_t group; + int ifindex; int sndbuf; - int vnet_hdr_sz; int ret; + bool do_notify = false; - if (cmd == TUNSETIFF || cmd == TUNSETQUEUE || _IOC_TYPE(cmd) == 0x89) { + if (cmd == TUNSETIFF || cmd == TUNSETQUEUE || + (_IOC_TYPE(cmd) == SOCK_IOC_TYPE && cmd != SIOCGSKNS)) { if (copy_from_user(&ifr, argp, ifreq_len)) return -EFAULT; } else { @@ -1874,21 +3063,29 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, 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 | IFF_NO_PI | IFF_ONE_QUEUE | - IFF_VNET_HDR | IFF_MULTI_QUEUE, - (unsigned int __user*)argp); - } else if (cmd == TUNSETQUEUE) + * TUNSETIFF. + */ + return put_user(IFF_TUN | IFF_TAP | IFF_NO_CARRIER | + TUN_FEATURES, (unsigned int __user*)argp); + } else if (cmd == TUNSETQUEUE) { return tun_set_queue(file, &ifr); + } else if (cmd == SIOCGSKNS) { + if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) + return -EPERM; + return open_related_ns(&net->ns, get_net_ns); + } - ret = 0; rtnl_lock(); - tun = __tun_get(tfile); - if (cmd == TUNSETIFF && !tun) { + tun = tun_get(tfile); + if (cmd == TUNSETIFF) { + ret = -EEXIST; + if (tun) + goto unlock; + ifr.ifr_name[IFNAMSIZ-1] = '\0'; - ret = tun_set_iff(tfile->net, file, &ifr); + ret = tun_set_iff(net, file, &ifr); if (ret) goto unlock; @@ -1897,17 +3094,38 @@ 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 = -EINVAL; + if (ifindex < 0) + 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); + netif_info(tun, drv, tun->dev, "tun_chr_ioctl cmd %u\n", cmd); + net = dev_net(tun->dev); ret = 0; switch (cmd) { case TUNGETIFF: - tun_get_iff(current->nsproxy->net_ns, tun, &ifr); + tun_get_iff(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; @@ -1917,25 +3135,27 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, /* Disable/Enable checksum */ /* [unimplemented] */ - tun_debug(KERN_INFO, tun, "ignored: set checksum %s\n", - arg ? "disabled" : "enabled"); + netif_info(tun, drv, tun->dev, "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 & TUN_PERSIST)) { - tun->flags |= TUN_PERSIST; + if (arg && !(tun->flags & IFF_PERSIST)) { + tun->flags |= IFF_PERSIST; __module_get(THIS_MODULE); + do_notify = true; } - if (!arg && (tun->flags & TUN_PERSIST)) { - tun->flags &= ~TUN_PERSIST; + if (!arg && (tun->flags & IFF_PERSIST)) { + tun->flags &= ~IFF_PERSIST; module_put(THIS_MODULE); + do_notify = true; } - tun_debug(KERN_INFO, tun, "persist %s\n", - arg ? "enabled" : "disabled"); + netif_info(tun, drv, tun->dev, "persist %s\n", + arg ? "enabled" : "disabled"); break; case TUNSETOWNER: @@ -1946,8 +3166,9 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, break; } tun->owner = owner; - tun_debug(KERN_INFO, tun, "owner set to %u\n", - from_kuid(&init_user_ns, tun->owner)); + do_notify = true; + netif_info(tun, drv, tun->dev, "owner set to %u\n", + from_kuid(&init_user_ns, tun->owner)); break; case TUNSETGROUP: @@ -1958,29 +3179,39 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, break; } tun->group = group; - tun_debug(KERN_INFO, tun, "group set to %u\n", - from_kgid(&init_user_ns, tun->group)); + do_notify = true; + netif_info(tun, drv, tun->dev, "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"); + netif_info(tun, drv, tun->dev, + "Linktype set failed because interface is up\n"); ret = -EBUSY; } else { + ret = call_netdevice_notifiers(NETDEV_PRE_TYPE_CHANGE, + tun->dev); + ret = notifier_to_errno(ret); + if (ret) { + netif_info(tun, drv, tun->dev, + "Refused to change device type\n"); + break; + } tun->dev->type = (int) arg; - tun_debug(KERN_INFO, tun, "linktype set to %d\n", - tun->dev->type); - ret = 0; + tun->dev->addr_len = tun_get_addr_len(tun->dev->type); + netif_info(tun, drv, tun->dev, "linktype set to %d\n", + tun->dev->type); + call_netdevice_notifiers(NETDEV_POST_TYPE_CHANGE, + tun->dev); } break; -#ifdef TUN_DEBUG case TUNSETDEBUG: - tun->debug = arg; + tun->msg_enable = (u32)arg; break; -#endif + case TUNSETOFFLOAD: ret = set_offload(tun, arg); break; @@ -1988,25 +3219,27 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, case TUNSETTXFILTER: /* Can be set only for TAPs */ ret = -EINVAL; - if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV) + 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; + netif_get_mac_address(&ifr.ifr_hwaddr, net, tun->dev->name); 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); + if (tun->dev->addr_len > sizeof(ifr.ifr_hwaddr)) { + ret = -EINVAL; + break; + } + ret = dev_set_mac_address_user(tun->dev, + (struct sockaddr_storage *)&ifr.ifr_hwaddr, + NULL); break; case TUNGETSNDBUF: @@ -2020,34 +3253,19 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, 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)) { + if (sndbuf <= 0) { ret = -EINVAL; break; } - tun->vnet_hdr_sz = vnet_hdr_sz; + tun->sndbuf = sndbuf; + tun_set_sndbuf(tun); break; case TUNATTACHFILTER: /* Can be set only for TAPs */ ret = -EINVAL; - if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV) + if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP) break; ret = -EFAULT; if (copy_from_user(&tun->fprog, argp, sizeof(tun->fprog))) @@ -2059,17 +3277,53 @@ static long __tun_chr_ioctl(struct file *file, unsigned int cmd, case TUNDETACHFILTER: /* Can be set only for TAPs */ ret = -EINVAL; - if ((tun->flags & TUN_TYPE_MASK) != TUN_TAP_DEV) + if ((tun->flags & TUN_TYPE_MASK) != IFF_TAP) break; ret = 0; tun_detach_filter(tun, tun->numqueues); break; - default: + 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; + + case TUNSETSTEERINGEBPF: + ret = tun_set_ebpf(tun, &tun->steering_prog, argp); + break; + + case TUNSETFILTEREBPF: + ret = tun_set_ebpf(tun, &tun->filter_prog, argp); + break; + + case TUNSETCARRIER: + ret = -EFAULT; + if (copy_from_user(&carrier, argp, sizeof(carrier))) + goto unlock; + + ret = tun_net_change_carrier(tun->dev, (bool)carrier); + break; + + case TUNGETDEVNETNS: + ret = -EPERM; + if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) + goto unlock; + ret = open_related_ns(&net->ns, get_net_ns); + break; + + default: + ret = tun_vnet_ioctl(&tun->vnet_hdr_sz, &tun->flags, cmd, argp); break; } + if (do_notify) + netdev_state_change(tun->dev); + unlock: rtnl_unlock(); if (tun) @@ -2117,13 +3371,17 @@ static int tun_chr_fasync(int fd, struct file *file, int on) struct tun_file *tfile = file->private_data; int ret; + if (on) { + ret = file_f_owner_allocate(file); + if (ret) + goto out; + } + if ((ret = fasync_helper(fd, file, on, &tfile->fasync)) < 0) goto out; if (on) { - ret = __f_setown(file, task_pid(current), PIDTYPE_PID, 0); - if (ret) - goto out; + __f_setown(file, task_pid(current), PIDTYPE_TGID, 0); tfile->flags |= TUN_FASYNC; } else tfile->flags &= ~TUN_FASYNC; @@ -2134,57 +3392,78 @@ out: 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(&init_net, AF_UNSPEC, GFP_KERNEL, - &tun_proto); + tfile = (struct tun_file *)sk_alloc(net, AF_UNSPEC, GFP_KERNEL, + &tun_proto, 0); if (!tfile) return -ENOMEM; - rcu_assign_pointer(tfile->tun, NULL); - tfile->net = get_net(current->nsproxy->net_ns); + if (ptr_ring_init(&tfile->tx_ring, 0, GFP_KERNEL)) { + sk_free(&tfile->sk); + return -ENOMEM; + } + + mutex_init(&tfile->napi_mutex); + RCU_INIT_POINTER(tfile->tun, NULL); tfile->flags = 0; + tfile->ifindex = 0; - rcu_assign_pointer(tfile->socket.wq, &tfile->wq); - init_waitqueue_head(&tfile->wq.wait); + init_waitqueue_head(&tfile->socket.wq.wait); tfile->socket.file = file; tfile->socket.ops = &tun_socket_ops; - sock_init_data(&tfile->socket, &tfile->sk); - sk_change_net(&tfile->sk, tfile->net); + sock_init_data_uid(&tfile->socket, &tfile->sk, current_fsuid()); tfile->sk.sk_write_space = tun_sock_write_space; tfile->sk.sk_sndbuf = INT_MAX; file->private_data = tfile; - set_bit(SOCK_EXTERNALLY_ALLOCATED, &tfile->socket.flags); INIT_LIST_HEAD(&tfile->next); sock_set_flag(&tfile->sk, SOCK_ZEROCOPY); + /* tun groks IOCB_NOWAIT just fine, mark it as such */ + file->f_mode |= FMODE_NOWAIT; return 0; } static int tun_chr_close(struct inode *inode, struct file *file) { struct tun_file *tfile = file->private_data; - struct net *net = tfile->net; tun_detach(tfile, true); - put_net(net); return 0; } +#ifdef CONFIG_PROC_FS +static void tun_chr_show_fdinfo(struct seq_file *m, struct file *file) +{ + struct tun_file *tfile = file->private_data; + struct tun_struct *tun; + struct ifreq ifr; + + memset(&ifr, 0, sizeof(ifr)); + + rtnl_lock(); + tun = tun_get(tfile); + if (tun) + tun_get_iff(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 = do_sync_read, - .aio_read = tun_chr_aio_read, - .write = do_sync_write, - .aio_write = tun_chr_aio_write, + .read_iter = tun_chr_read_iter, + .write_iter = tun_chr_write_iter, .poll = tun_chr_poll, .unlocked_ioctl = tun_chr_ioctl, #ifdef CONFIG_COMPAT @@ -2192,7 +3471,10 @@ static const struct file_operations tun_fops = { #endif .open = tun_chr_open, .release = tun_chr_close, - .fasync = tun_chr_fasync + .fasync = tun_chr_fasync, +#ifdef CONFIG_PROC_FS + .show_fdinfo = tun_chr_show_fdinfo, +#endif }; static struct miscdevice tun_miscdev = { @@ -2204,18 +3486,33 @@ static struct miscdevice tun_miscdev = { /* 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; +static void tun_default_link_ksettings(struct net_device *dev, + struct ethtool_link_ksettings *cmd) +{ + ethtool_link_ksettings_zero_link_mode(cmd, supported); + ethtool_link_ksettings_zero_link_mode(cmd, advertising); + cmd->base.speed = SPEED_10000; + cmd->base.duplex = DUPLEX_FULL; + cmd->base.port = PORT_TP; + cmd->base.phy_address = 0; + cmd->base.autoneg = AUTONEG_DISABLE; +} + +static int tun_get_link_ksettings(struct net_device *dev, + struct ethtool_link_ksettings *cmd) +{ + struct tun_struct *tun = netdev_priv(dev); + + memcpy(cmd, &tun->link_ksettings, sizeof(*cmd)); + return 0; +} + +static int tun_set_link_ksettings(struct net_device *dev, + const struct ethtool_link_ksettings *cmd) +{ + struct tun_struct *tun = netdev_priv(dev); + + memcpy(&tun->link_ksettings, cmd, sizeof(*cmd)); return 0; } @@ -2223,52 +3520,149 @@ 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)); + strscpy(info->driver, DRV_NAME, sizeof(info->driver)); + strscpy(info->version, DRV_VERSION, sizeof(info->version)); switch (tun->flags & TUN_TYPE_MASK) { - case TUN_TUN_DEV: - strlcpy(info->bus_info, "tun", sizeof(info->bus_info)); + case IFF_TUN: + strscpy(info->bus_info, "tun", sizeof(info->bus_info)); break; - case TUN_TAP_DEV: - strlcpy(info->bus_info, "tap", sizeof(info->bus_info)); + case IFF_TAP: + strscpy(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 + + return tun->msg_enable; } 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 + + tun->msg_enable = value; +} + +static int tun_get_coalesce(struct net_device *dev, + struct ethtool_coalesce *ec, + struct kernel_ethtool_coalesce *kernel_coal, + struct netlink_ext_ack *extack) +{ + struct tun_struct *tun = netdev_priv(dev); + + ec->rx_max_coalesced_frames = tun->rx_batched; + + return 0; +} + +static int tun_set_coalesce(struct net_device *dev, + struct ethtool_coalesce *ec, + struct kernel_ethtool_coalesce *kernel_coal, + struct netlink_ext_ack *extack) +{ + struct tun_struct *tun = netdev_priv(dev); + + if (ec->rx_max_coalesced_frames > NAPI_POLL_WEIGHT) + tun->rx_batched = NAPI_POLL_WEIGHT; + else + tun->rx_batched = ec->rx_max_coalesced_frames; + + return 0; +} + +static void tun_get_channels(struct net_device *dev, + struct ethtool_channels *channels) +{ + struct tun_struct *tun = netdev_priv(dev); + + channels->combined_count = tun->numqueues; + channels->max_combined = tun->flags & IFF_MULTI_QUEUE ? MAX_TAP_QUEUES : 1; } static const struct ethtool_ops tun_ethtool_ops = { - .get_settings = tun_get_settings, + .supported_coalesce_params = ETHTOOL_COALESCE_RX_MAX_FRAMES, .get_drvinfo = tun_get_drvinfo, .get_msglevel = tun_get_msglevel, .set_msglevel = tun_set_msglevel, .get_link = ethtool_op_get_link, + .get_channels = tun_get_channels, + .get_ts_info = ethtool_op_get_ts_info, + .get_coalesce = tun_get_coalesce, + .set_coalesce = tun_set_coalesce, + .get_link_ksettings = tun_get_link_ksettings, + .set_link_ksettings = tun_set_link_ksettings, }; +static int tun_queue_resize(struct tun_struct *tun) +{ + struct net_device *dev = tun->dev; + struct tun_file *tfile; + struct ptr_ring **rings; + int n = tun->numqueues + tun->numdisabled; + int ret, i; + + rings = kmalloc_array(n, sizeof(*rings), GFP_KERNEL); + if (!rings) + return -ENOMEM; + + for (i = 0; i < tun->numqueues; i++) { + tfile = rtnl_dereference(tun->tfiles[i]); + rings[i] = &tfile->tx_ring; + } + list_for_each_entry(tfile, &tun->disabled, next) + rings[i++] = &tfile->tx_ring; + + ret = ptr_ring_resize_multiple_bh(rings, n, + dev->tx_queue_len, GFP_KERNEL, + tun_ptr_free); + + kfree(rings); + 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); + int i; + + 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; + case NETDEV_UP: + for (i = 0; i < tun->numqueues; i++) { + struct tun_file *tfile; + + tfile = rtnl_dereference(tun->tfiles[i]); + tfile->socket.sk->sk_write_space(tfile->socket.sk); + } + 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) { @@ -2281,17 +3675,28 @@ static int __init tun_init(void) pr_err("Can't register misc device %d\n", TUN_MINOR); goto err_misc; } + + ret = register_netdevice_notifier(&tun_notifier_block); + if (ret) { + pr_err("Can't register netdevice notifier\n"); + goto err_notifier; + } + return 0; + +err_notifier: + misc_deregister(&tun_miscdev); err_misc: rtnl_link_unregister(&tun_link_ops); err_linkops: return ret; } -static void tun_cleanup(void) +static void __exit 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 @@ -2310,6 +3715,19 @@ struct socket *tun_get_socket(struct file *file) } EXPORT_SYMBOL_GPL(tun_get_socket); +struct ptr_ring *tun_get_tx_ring(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->tx_ring; +} +EXPORT_SYMBOL_GPL(tun_get_tx_ring); + module_init(tun_init); module_exit(tun_cleanup); MODULE_DESCRIPTION(DRV_DESCRIPTION); @@ -2317,3 +3735,4 @@ MODULE_AUTHOR(DRV_COPYRIGHT); MODULE_LICENSE("GPL"); MODULE_ALIAS_MISCDEV(TUN_MINOR); MODULE_ALIAS("devname:net/tun"); +MODULE_IMPORT_NS("NETDEV_INTERNAL"); |