linux/net/batman-adv/soft-interface.c

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// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2007-2019 B.A.T.M.A.N. contributors:
*
* Marek Lindner, Simon Wunderlich
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "soft-interface.h"
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#include "main.h"
#include <linux/atomic.h>
#include <linux/byteorder/generic.h>
#include <linux/cache.h>
#include <linux/compiler.h>
#include <linux/cpumask.h>
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#include <linux/errno.h>
#include <linux/etherdevice.h>
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#include <linux/ethtool.h>
#include <linux/gfp.h>
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#include <linux/if_ether.h>
#include <linux/if_vlan.h>
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#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/kref.h>
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#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/percpu.h>
#include <linux/printk.h>
#include <linux/random.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/rtnetlink.h>
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#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/socket.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/types.h>
#include <uapi/linux/batadv_packet.h>
#include <uapi/linux/batman_adv.h>
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#include "bat_algo.h"
#include "bridge_loop_avoidance.h"
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#include "debugfs.h"
#include "distributed-arp-table.h"
#include "gateway_client.h"
#include "hard-interface.h"
#include "multicast.h"
batman-adv: network coding - add the initial infrastructure code Network coding exploits the 802.11 shared medium to allow multiple packets to be sent in a single transmission. In brief, a relay can XOR two packets, and send the coded packet to two destinations. The receivers can decode one of the original packets by XOR'ing the coded packet with the other original packet. This will lead to increased throughput in topologies where two packets cross one relay. In a simple topology with three nodes, it takes four transmissions without network coding to get one packet from Node A to Node B and one from Node B to Node A: 1. Node A ---- p1 ---> Node R Node B 2. Node A Node R <--- p2 ---- Node B 3. Node A <--- p2 ---- Node R Node B 4. Node A Node R ---- p1 ---> Node B With network coding, the relay only needs one transmission, which saves us one slot of valuable airtime: 1. Node A ---- p1 ---> Node R Node B 2. Node A Node R <--- p2 ---- Node B 3. Node A <- p1 x p2 - Node R - p1 x p2 -> Node B The same principle holds for a topology including five nodes. Here the packets from Node A and Node B are overheard by Node C and Node D, respectively. This allows Node R to send a network coded packet to save one transmission: Node A Node B | \ / | | p1 p2 | | \ / | p1 > Node R < p2 | | | / \ | | p1 x p2 p1 x p2 | v / \ v / \ Node C < > Node D More information is available on the open-mesh.org wiki[1]. This patch adds the initial code to support network coding in batman-adv. It sets up a worker thread to do house keeping and adds a sysfs file to enable/disable network coding. The feature is disabled by default, as it requires a wifi-driver with working promiscuous mode, and also because it adds a small delay at each hop. [1] http://www.open-mesh.org/projects/batman-adv/wiki/Catwoman Signed-off-by: Martin Hundebøll <martin@hundeboll.net> Signed-off-by: Marek Lindner <lindner_marek@yahoo.de> Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2013-01-25 18:12:38 +08:00
#include "network-coding.h"
#include "originator.h"
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#include "send.h"
#include "sysfs.h"
#include "translation-table.h"
/**
* batadv_skb_head_push() - Increase header size and move (push) head pointer
* @skb: packet buffer which should be modified
* @len: number of bytes to add
*
* Return: 0 on success or negative error number in case of failure
*/
int batadv_skb_head_push(struct sk_buff *skb, unsigned int len)
{
int result;
/* TODO: We must check if we can release all references to non-payload
* data using __skb_header_release in our skbs to allow skb_cow_header
* to work optimally. This means that those skbs are not allowed to read
* or write any data which is before the current position of skb->data
* after that call and thus allow other skbs with the same data buffer
* to write freely in that area.
*/
result = skb_cow_head(skb, len);
if (result < 0)
return result;
skb_push(skb, len);
return 0;
}
static int batadv_interface_open(struct net_device *dev)
{
netif_start_queue(dev);
return 0;
}
static int batadv_interface_release(struct net_device *dev)
{
netif_stop_queue(dev);
return 0;
}
/**
* batadv_sum_counter() - Sum the cpu-local counters for index 'idx'
* @bat_priv: the bat priv with all the soft interface information
* @idx: index of counter to sum up
*
* Return: sum of all cpu-local counters
*/
static u64 batadv_sum_counter(struct batadv_priv *bat_priv, size_t idx)
{
u64 *counters, sum = 0;
int cpu;
for_each_possible_cpu(cpu) {
counters = per_cpu_ptr(bat_priv->bat_counters, cpu);
sum += counters[idx];
}
return sum;
}
static struct net_device_stats *batadv_interface_stats(struct net_device *dev)
{
struct batadv_priv *bat_priv = netdev_priv(dev);
struct net_device_stats *stats = &dev->stats;
stats->tx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_TX);
stats->tx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_TX_BYTES);
stats->tx_dropped = batadv_sum_counter(bat_priv, BATADV_CNT_TX_DROPPED);
stats->rx_packets = batadv_sum_counter(bat_priv, BATADV_CNT_RX);
stats->rx_bytes = batadv_sum_counter(bat_priv, BATADV_CNT_RX_BYTES);
return stats;
}
static int batadv_interface_set_mac_addr(struct net_device *dev, void *p)
{
struct batadv_priv *bat_priv = netdev_priv(dev);
struct batadv_softif_vlan *vlan;
struct sockaddr *addr = p;
u8 old_addr[ETH_ALEN];
if (!is_valid_ether_addr(addr->sa_data))
return -EADDRNOTAVAIL;
ether_addr_copy(old_addr, dev->dev_addr);
ether_addr_copy(dev->dev_addr, addr->sa_data);
/* only modify transtable if it has been initialized before */
if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
return 0;
rcu_read_lock();
hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
batadv_tt_local_remove(bat_priv, old_addr, vlan->vid,
"mac address changed", false);
batadv_tt_local_add(dev, addr->sa_data, vlan->vid,
BATADV_NULL_IFINDEX, BATADV_NO_MARK);
}
rcu_read_unlock();
return 0;
}
static int batadv_interface_change_mtu(struct net_device *dev, int new_mtu)
{
/* check ranges */
if (new_mtu < 68 || new_mtu > batadv_hardif_min_mtu(dev))
return -EINVAL;
dev->mtu = new_mtu;
return 0;
}
/**
* batadv_interface_set_rx_mode() - set the rx mode of a device
* @dev: registered network device to modify
*
* We do not actually need to set any rx filters for the virtual batman
* soft interface. However a dummy handler enables a user to set static
* multicast listeners for instance.
*/
static void batadv_interface_set_rx_mode(struct net_device *dev)
{
}
static netdev_tx_t batadv_interface_tx(struct sk_buff *skb,
struct net_device *soft_iface)
{
struct ethhdr *ethhdr;
struct batadv_priv *bat_priv = netdev_priv(soft_iface);
struct batadv_hard_iface *primary_if = NULL;
struct batadv_bcast_packet *bcast_packet;
static const u8 stp_addr[ETH_ALEN] = {0x01, 0x80, 0xC2, 0x00,
0x00, 0x00};
static const u8 ectp_addr[ETH_ALEN] = {0xCF, 0x00, 0x00, 0x00,
0x00, 0x00};
enum batadv_dhcp_recipient dhcp_rcp = BATADV_DHCP_NO;
u8 *dst_hint = NULL, chaddr[ETH_ALEN];
struct vlan_ethhdr *vhdr;
unsigned int header_len = 0;
int data_len = skb->len, ret;
unsigned long brd_delay = 1;
bool do_bcast = false, client_added;
unsigned short vid;
u32 seqno;
int gw_mode;
enum batadv_forw_mode forw_mode;
struct batadv_orig_node *mcast_single_orig = NULL;
int network_offset = ETH_HLEN;
__be16 proto;
if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
goto dropped;
/* reset control block to avoid left overs from previous users */
memset(skb->cb, 0, sizeof(struct batadv_skb_cb));
netif_trans_update(soft_iface);
vid = batadv_get_vid(skb, 0);
skb_reset_mac_header(skb);
ethhdr = eth_hdr(skb);
proto = ethhdr->h_proto;
switch (ntohs(proto)) {
case ETH_P_8021Q:
batman-adv: fix uninit-value in batadv_interface_tx() KMSAN reported batadv_interface_tx() was possibly using a garbage value [1] batadv_get_vid() does have a pskb_may_pull() call but batadv_interface_tx() does not actually make sure this did not fail. [1] BUG: KMSAN: uninit-value in batadv_interface_tx+0x908/0x1e40 net/batman-adv/soft-interface.c:231 CPU: 0 PID: 10006 Comm: syz-executor469 Not tainted 4.20.0-rc7+ #5 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x173/0x1d0 lib/dump_stack.c:113 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313 batadv_interface_tx+0x908/0x1e40 net/batman-adv/soft-interface.c:231 __netdev_start_xmit include/linux/netdevice.h:4356 [inline] netdev_start_xmit include/linux/netdevice.h:4365 [inline] xmit_one net/core/dev.c:3257 [inline] dev_hard_start_xmit+0x607/0xc40 net/core/dev.c:3273 __dev_queue_xmit+0x2e42/0x3bc0 net/core/dev.c:3843 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3876 packet_snd net/packet/af_packet.c:2928 [inline] packet_sendmsg+0x8306/0x8f30 net/packet/af_packet.c:2953 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] __sys_sendto+0x8c4/0xac0 net/socket.c:1788 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:1796 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x441889 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 bb 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffdda6fd468 EFLAGS: 00000216 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000441889 RDX: 000000000000000e RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000216 R12: 00007ffdda6fd4c0 R13: 00007ffdda6fd4b0 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline] kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185 slab_post_alloc_hook mm/slab.h:446 [inline] slab_alloc_node mm/slub.c:2759 [inline] __kmalloc_node_track_caller+0xe18/0x1030 mm/slub.c:4383 __kmalloc_reserve net/core/skbuff.c:137 [inline] __alloc_skb+0x309/0xa20 net/core/skbuff.c:205 alloc_skb include/linux/skbuff.h:998 [inline] alloc_skb_with_frags+0x1c7/0xac0 net/core/skbuff.c:5220 sock_alloc_send_pskb+0xafd/0x10e0 net/core/sock.c:2083 packet_alloc_skb net/packet/af_packet.c:2781 [inline] packet_snd net/packet/af_packet.c:2872 [inline] packet_sendmsg+0x661a/0x8f30 net/packet/af_packet.c:2953 sock_sendmsg_nosec net/socket.c:621 [inline] sock_sendmsg net/socket.c:631 [inline] __sys_sendto+0x8c4/0xac0 net/socket.c:1788 __do_sys_sendto net/socket.c:1800 [inline] __se_sys_sendto+0x107/0x130 net/socket.c:1796 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Fixes: c6c8fea29769 ("net: Add batman-adv meshing protocol") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: Marek Lindner <mareklindner@neomailbox.ch> Cc: Simon Wunderlich <sw@simonwunderlich.de> Cc: Antonio Quartulli <a@unstable.cc> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-12 06:41:22 +08:00
if (!pskb_may_pull(skb, sizeof(*vhdr)))
goto dropped;
vhdr = vlan_eth_hdr(skb);
proto = vhdr->h_vlan_encapsulated_proto;
/* drop batman-in-batman packets to prevent loops */
if (proto != htons(ETH_P_BATMAN)) {
network_offset += VLAN_HLEN;
break;
}
/* fall through */
case ETH_P_BATMAN:
goto dropped;
}
skb_set_network_header(skb, network_offset);
if (batadv_bla_tx(bat_priv, skb, vid))
goto dropped;
/* skb->data might have been reallocated by batadv_bla_tx() */
ethhdr = eth_hdr(skb);
batman-adv: improved client announcement mechanism The client announcement mechanism informs every mesh node in the network of any connected non-mesh client, in order to find the path towards that client from any given point in the mesh. The old implementation was based on the simple idea of appending a data buffer to each OGM containing all the client MAC addresses the node is serving. All other nodes can populate their global translation tables (table which links client MAC addresses to node addresses) using this MAC address buffer and linking it to the node's address contained in the OGM. A node that wants to contact a client has to lookup the node the client is connected to and its address in the global translation table. It is easy to understand that this implementation suffers from several issues: - big overhead (each and every OGM contains the entire list of connected clients) - high latencies for client route updates due to long OGM trip time and OGM losses The new implementation addresses these issues by appending client changes (new client joined or a client left) to the OGM instead of filling it with all the client addresses each time. In this way nodes can modify their global tables by means of "updates", thus reducing the overhead within the OGMs. To keep the entire network in sync each node maintains a translation table version number (ttvn) and a translation table checksum. These values are spread with the OGM to allow all the network participants to determine whether or not they need to update their translation table information. When a translation table lookup is performed in order to send a packet to a client attached to another node, the destination's ttvn is added to the payload packet. Forwarding nodes can compare the packet's ttvn with their destination's ttvn (this node could have a fresher information than the source) and re-route the packet if necessary. This greatly reduces the packet loss of clients roaming from one AP to the next. Signed-off-by: Antonio Quartulli <ordex@autistici.org> Signed-off-by: Marek Lindner <lindner_marek@yahoo.de> Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-04-27 20:27:44 +08:00
/* Register the client MAC in the transtable */
if (!is_multicast_ether_addr(ethhdr->h_source) &&
!batadv_bla_is_loopdetect_mac(ethhdr->h_source)) {
client_added = batadv_tt_local_add(soft_iface, ethhdr->h_source,
vid, skb->skb_iif,
skb->mark);
if (!client_added)
goto dropped;
}
/* Snoop address candidates from DHCPACKs for early DAT filling */
batadv_dat_snoop_outgoing_dhcp_ack(bat_priv, skb, proto, vid);
/* don't accept stp packets. STP does not help in meshes.
* better use the bridge loop avoidance ...
*
* The same goes for ECTP sent at least by some Cisco Switches,
* it might confuse the mesh when used with bridge loop avoidance.
*/
if (batadv_compare_eth(ethhdr->h_dest, stp_addr))
goto dropped;
if (batadv_compare_eth(ethhdr->h_dest, ectp_addr))
goto dropped;
gw_mode = atomic_read(&bat_priv->gw.mode);
if (is_multicast_ether_addr(ethhdr->h_dest)) {
/* if gw mode is off, broadcast every packet */
if (gw_mode == BATADV_GW_MODE_OFF) {
do_bcast = true;
goto send;
}
dhcp_rcp = batadv_gw_dhcp_recipient_get(skb, &header_len,
chaddr);
/* skb->data may have been modified by
* batadv_gw_dhcp_recipient_get()
*/
ethhdr = eth_hdr(skb);
/* if gw_mode is on, broadcast any non-DHCP message.
* All the DHCP packets are going to be sent as unicast
*/
if (dhcp_rcp == BATADV_DHCP_NO) {
do_bcast = true;
goto send;
}
if (dhcp_rcp == BATADV_DHCP_TO_CLIENT)
dst_hint = chaddr;
else if ((gw_mode == BATADV_GW_MODE_SERVER) &&
(dhcp_rcp == BATADV_DHCP_TO_SERVER))
/* gateways should not forward any DHCP message if
* directed to a DHCP server
*/
goto dropped;
send:
if (do_bcast && !is_broadcast_ether_addr(ethhdr->h_dest)) {
forw_mode = batadv_mcast_forw_mode(bat_priv, skb,
&mcast_single_orig);
if (forw_mode == BATADV_FORW_NONE)
goto dropped;
if (forw_mode == BATADV_FORW_SINGLE)
do_bcast = false;
}
}
batadv_skb_set_priority(skb, 0);
/* ethernet packet should be broadcasted */
if (do_bcast) {
primary_if = batadv_primary_if_get_selected(bat_priv);
if (!primary_if)
goto dropped;
/* in case of ARP request, we do not immediately broadcasti the
* packet, instead we first wait for DAT to try to retrieve the
* correct ARP entry
*/
if (batadv_dat_snoop_outgoing_arp_request(bat_priv, skb))
brd_delay = msecs_to_jiffies(ARP_REQ_DELAY);
if (batadv_skb_head_push(skb, sizeof(*bcast_packet)) < 0)
goto dropped;
bcast_packet = (struct batadv_bcast_packet *)skb->data;
bcast_packet->version = BATADV_COMPAT_VERSION;
bcast_packet->ttl = BATADV_TTL;
/* batman packet type: broadcast */
bcast_packet->packet_type = BATADV_BCAST;
bcast_packet->reserved = 0;
/* hw address of first interface is the orig mac because only
* this mac is known throughout the mesh
*/
ether_addr_copy(bcast_packet->orig,
primary_if->net_dev->dev_addr);
/* set broadcast sequence number */
seqno = atomic_inc_return(&bat_priv->bcast_seqno);
bcast_packet->seqno = htonl(seqno);
batadv_add_bcast_packet_to_list(bat_priv, skb, brd_delay, true);
/* a copy is stored in the bcast list, therefore removing
* the original skb.
*/
consume_skb(skb);
/* unicast packet */
} else {
/* DHCP packets going to a server will use the GW feature */
if (dhcp_rcp == BATADV_DHCP_TO_SERVER) {
ret = batadv_gw_out_of_range(bat_priv, skb);
if (ret)
goto dropped;
ret = batadv_send_skb_via_gw(bat_priv, skb, vid);
} else if (mcast_single_orig) {
ret = batadv_send_skb_unicast(bat_priv, skb,
BATADV_UNICAST, 0,
mcast_single_orig, vid);
} else {
if (batadv_dat_snoop_outgoing_arp_request(bat_priv,
skb))
goto dropped;
batadv_dat_snoop_outgoing_arp_reply(bat_priv, skb);
ret = batadv_send_skb_via_tt(bat_priv, skb, dst_hint,
vid);
}
if (ret != NET_XMIT_SUCCESS)
goto dropped_freed;
}
batadv_inc_counter(bat_priv, BATADV_CNT_TX);
batadv_add_counter(bat_priv, BATADV_CNT_TX_BYTES, data_len);
goto end;
dropped:
kfree_skb(skb);
dropped_freed:
batadv_inc_counter(bat_priv, BATADV_CNT_TX_DROPPED);
end:
if (mcast_single_orig)
batadv_orig_node_put(mcast_single_orig);
if (primary_if)
batadv_hardif_put(primary_if);
return NETDEV_TX_OK;
}
/**
* batadv_interface_rx() - receive ethernet frame on local batman-adv interface
* @soft_iface: local interface which will receive the ethernet frame
* @skb: ethernet frame for @soft_iface
* @hdr_size: size of already parsed batman-adv header
* @orig_node: originator from which the batman-adv packet was sent
*
* Sends a ethernet frame to the receive path of the local @soft_iface.
* skb->data has still point to the batman-adv header with the size @hdr_size.
* The caller has to have parsed this header already and made sure that at least
* @hdr_size bytes are still available for pull in @skb.
*
* The packet may still get dropped. This can happen when the encapsulated
* ethernet frame is invalid or contains again an batman-adv packet. Also
* unicast packets will be dropped directly when it was sent between two
* isolated clients.
*/
void batadv_interface_rx(struct net_device *soft_iface,
struct sk_buff *skb, int hdr_size,
struct batadv_orig_node *orig_node)
{
struct batadv_bcast_packet *batadv_bcast_packet;
struct batadv_priv *bat_priv = netdev_priv(soft_iface);
struct vlan_ethhdr *vhdr;
struct ethhdr *ethhdr;
unsigned short vid;
bool is_bcast;
batadv_bcast_packet = (struct batadv_bcast_packet *)skb->data;
is_bcast = (batadv_bcast_packet->packet_type == BATADV_BCAST);
skb_pull_rcsum(skb, hdr_size);
skb_reset_mac_header(skb);
/* clean the netfilter state now that the batman-adv header has been
* removed
*/
nf_reset(skb);
if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
goto dropped;
vid = batadv_get_vid(skb, 0);
ethhdr = eth_hdr(skb);
switch (ntohs(ethhdr->h_proto)) {
case ETH_P_8021Q:
if (!pskb_may_pull(skb, VLAN_ETH_HLEN))
goto dropped;
vhdr = (struct vlan_ethhdr *)skb->data;
/* drop batman-in-batman packets to prevent loops */
if (vhdr->h_vlan_encapsulated_proto != htons(ETH_P_BATMAN))
break;
/* fall through */
case ETH_P_BATMAN:
goto dropped;
}
/* skb->dev & skb->pkt_type are set here */
skb->protocol = eth_type_trans(skb, soft_iface);
skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
batadv_inc_counter(bat_priv, BATADV_CNT_RX);
batadv_add_counter(bat_priv, BATADV_CNT_RX_BYTES,
skb->len + ETH_HLEN);
/* Let the bridge loop avoidance check the packet. If will
* not handle it, we can safely push it up.
*/
if (batadv_bla_rx(bat_priv, skb, vid, is_bcast))
goto out;
if (orig_node)
batadv_tt_add_temporary_global_entry(bat_priv, orig_node,
ethhdr->h_source, vid);
if (is_multicast_ether_addr(ethhdr->h_dest)) {
/* set the mark on broadcast packets if AP isolation is ON and
* the packet is coming from an "isolated" client
*/
if (batadv_vlan_ap_isola_get(bat_priv, vid) &&
batadv_tt_global_is_isolated(bat_priv, ethhdr->h_source,
vid)) {
/* save bits in skb->mark not covered by the mask and
* apply the mark on the rest
*/
skb->mark &= ~bat_priv->isolation_mark_mask;
skb->mark |= bat_priv->isolation_mark;
}
} else if (batadv_is_ap_isolated(bat_priv, ethhdr->h_source,
ethhdr->h_dest, vid)) {
goto dropped;
}
netif_rx(skb);
goto out;
dropped:
kfree_skb(skb);
out:
return;
}
/**
* batadv_softif_vlan_release() - release vlan from lists and queue for free
* after rcu grace period
* @ref: kref pointer of the vlan object
*/
static void batadv_softif_vlan_release(struct kref *ref)
{
struct batadv_softif_vlan *vlan;
vlan = container_of(ref, struct batadv_softif_vlan, refcount);
spin_lock_bh(&vlan->bat_priv->softif_vlan_list_lock);
hlist_del_rcu(&vlan->list);
spin_unlock_bh(&vlan->bat_priv->softif_vlan_list_lock);
kfree_rcu(vlan, rcu);
}
/**
* batadv_softif_vlan_put() - decrease the vlan object refcounter and
* possibly release it
* @vlan: the vlan object to release
*/
void batadv_softif_vlan_put(struct batadv_softif_vlan *vlan)
{
if (!vlan)
return;
kref_put(&vlan->refcount, batadv_softif_vlan_release);
}
/**
* batadv_softif_vlan_get() - get the vlan object for a specific vid
* @bat_priv: the bat priv with all the soft interface information
* @vid: the identifier of the vlan object to retrieve
*
* Return: the private data of the vlan matching the vid passed as argument or
* NULL otherwise. The refcounter of the returned object is incremented by 1.
*/
struct batadv_softif_vlan *batadv_softif_vlan_get(struct batadv_priv *bat_priv,
unsigned short vid)
{
struct batadv_softif_vlan *vlan_tmp, *vlan = NULL;
rcu_read_lock();
hlist_for_each_entry_rcu(vlan_tmp, &bat_priv->softif_vlan_list, list) {
if (vlan_tmp->vid != vid)
continue;
if (!kref_get_unless_zero(&vlan_tmp->refcount))
continue;
vlan = vlan_tmp;
break;
}
rcu_read_unlock();
return vlan;
}
/**
* batadv_softif_create_vlan() - allocate the needed resources for a new vlan
* @bat_priv: the bat priv with all the soft interface information
* @vid: the VLAN identifier
*
* Return: 0 on success, a negative error otherwise.
*/
int batadv_softif_create_vlan(struct batadv_priv *bat_priv, unsigned short vid)
{
struct batadv_softif_vlan *vlan;
int err;
spin_lock_bh(&bat_priv->softif_vlan_list_lock);
vlan = batadv_softif_vlan_get(bat_priv, vid);
if (vlan) {
batadv_softif_vlan_put(vlan);
spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
return -EEXIST;
}
vlan = kzalloc(sizeof(*vlan), GFP_ATOMIC);
if (!vlan) {
spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
return -ENOMEM;
}
vlan->bat_priv = bat_priv;
vlan->vid = vid;
kref_init(&vlan->refcount);
atomic_set(&vlan->ap_isolation, 0);
kref_get(&vlan->refcount);
hlist_add_head_rcu(&vlan->list, &bat_priv->softif_vlan_list);
spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
/* batadv_sysfs_add_vlan cannot be in the spinlock section due to the
* sleeping behavior of the sysfs functions and the fs_reclaim lock
*/
err = batadv_sysfs_add_vlan(bat_priv->soft_iface, vlan);
if (err) {
/* ref for the function */
batadv_softif_vlan_put(vlan);
/* ref for the list */
batadv_softif_vlan_put(vlan);
return err;
}
/* add a new TT local entry. This one will be marked with the NOPURGE
* flag
*/
batadv_tt_local_add(bat_priv->soft_iface,
bat_priv->soft_iface->dev_addr, vid,
BATADV_NULL_IFINDEX, BATADV_NO_MARK);
/* don't return reference to new softif_vlan */
batadv_softif_vlan_put(vlan);
return 0;
}
/**
* batadv_softif_destroy_vlan() - remove and destroy a softif_vlan object
* @bat_priv: the bat priv with all the soft interface information
* @vlan: the object to remove
*/
static void batadv_softif_destroy_vlan(struct batadv_priv *bat_priv,
struct batadv_softif_vlan *vlan)
{
/* explicitly remove the associated TT local entry because it is marked
* with the NOPURGE flag
*/
batadv_tt_local_remove(bat_priv, bat_priv->soft_iface->dev_addr,
vlan->vid, "vlan interface destroyed", false);
batadv_sysfs_del_vlan(bat_priv, vlan);
batadv_softif_vlan_put(vlan);
}
/**
* batadv_interface_add_vid() - ndo_add_vid API implementation
* @dev: the netdev of the mesh interface
* @proto: protocol of the the vlan id
* @vid: identifier of the new vlan
*
* Set up all the internal structures for handling the new vlan on top of the
* mesh interface
*
* Return: 0 on success or a negative error code in case of failure.
*/
static int batadv_interface_add_vid(struct net_device *dev, __be16 proto,
unsigned short vid)
{
struct batadv_priv *bat_priv = netdev_priv(dev);
struct batadv_softif_vlan *vlan;
int ret;
/* only 802.1Q vlans are supported.
* batman-adv does not know how to handle other types
*/
if (proto != htons(ETH_P_8021Q))
return -EINVAL;
vid |= BATADV_VLAN_HAS_TAG;
/* if a new vlan is getting created and it already exists, it means that
* it was not deleted yet. batadv_softif_vlan_get() increases the
* refcount in order to revive the object.
*
* if it does not exist then create it.
*/
vlan = batadv_softif_vlan_get(bat_priv, vid);
if (!vlan)
return batadv_softif_create_vlan(bat_priv, vid);
/* recreate the sysfs object if it was already destroyed (and it should
* be since we received a kill_vid() for this vlan
*/
if (!vlan->kobj) {
ret = batadv_sysfs_add_vlan(bat_priv->soft_iface, vlan);
if (ret) {
batadv_softif_vlan_put(vlan);
return ret;
}
}
/* add a new TT local entry. This one will be marked with the NOPURGE
* flag. This must be added again, even if the vlan object already
* exists, because the entry was deleted by kill_vid()
*/
batadv_tt_local_add(bat_priv->soft_iface,
bat_priv->soft_iface->dev_addr, vid,
BATADV_NULL_IFINDEX, BATADV_NO_MARK);
return 0;
}
/**
* batadv_interface_kill_vid() - ndo_kill_vid API implementation
* @dev: the netdev of the mesh interface
* @proto: protocol of the the vlan id
* @vid: identifier of the deleted vlan
*
* Destroy all the internal structures used to handle the vlan identified by vid
* on top of the mesh interface
*
* Return: 0 on success, -EINVAL if the specified prototype is not ETH_P_8021Q
* or -ENOENT if the specified vlan id wasn't registered.
*/
static int batadv_interface_kill_vid(struct net_device *dev, __be16 proto,
unsigned short vid)
{
struct batadv_priv *bat_priv = netdev_priv(dev);
struct batadv_softif_vlan *vlan;
/* only 802.1Q vlans are supported. batman-adv does not know how to
* handle other types
*/
if (proto != htons(ETH_P_8021Q))
return -EINVAL;
vlan = batadv_softif_vlan_get(bat_priv, vid | BATADV_VLAN_HAS_TAG);
if (!vlan)
return -ENOENT;
batadv_softif_destroy_vlan(bat_priv, vlan);
/* finally free the vlan object */
batadv_softif_vlan_put(vlan);
return 0;
}
/* batman-adv network devices have devices nesting below it and are a special
* "super class" of normal network devices; split their locks off into a
* separate class since they always nest.
*/
static struct lock_class_key batadv_netdev_xmit_lock_key;
static struct lock_class_key batadv_netdev_addr_lock_key;
/**
* batadv_set_lockdep_class_one() - Set lockdep class for a single tx queue
* @dev: device which owns the tx queue
* @txq: tx queue to modify
* @_unused: always NULL
*/
static void batadv_set_lockdep_class_one(struct net_device *dev,
struct netdev_queue *txq,
void *_unused)
{
lockdep_set_class(&txq->_xmit_lock, &batadv_netdev_xmit_lock_key);
}
/**
* batadv_set_lockdep_class() - Set txq and addr_list lockdep class
* @dev: network device to modify
*/
static void batadv_set_lockdep_class(struct net_device *dev)
{
lockdep_set_class(&dev->addr_list_lock, &batadv_netdev_addr_lock_key);
netdev_for_each_tx_queue(dev, batadv_set_lockdep_class_one, NULL);
}
/**
* batadv_softif_init_late() - late stage initialization of soft interface
* @dev: registered network device to modify
*
* Return: error code on failures
*/
static int batadv_softif_init_late(struct net_device *dev)
{
struct batadv_priv *bat_priv;
u32 random_seqno;
int ret;
size_t cnt_len = sizeof(u64) * BATADV_CNT_NUM;
batadv_set_lockdep_class(dev);
bat_priv = netdev_priv(dev);
bat_priv->soft_iface = dev;
/* batadv_interface_stats() needs to be available as soon as
* register_netdevice() has been called
*/
bat_priv->bat_counters = __alloc_percpu(cnt_len, __alignof__(u64));
if (!bat_priv->bat_counters)
return -ENOMEM;
atomic_set(&bat_priv->aggregated_ogms, 1);
atomic_set(&bat_priv->bonding, 0);
#ifdef CONFIG_BATMAN_ADV_BLA
atomic_set(&bat_priv->bridge_loop_avoidance, 1);
#endif
#ifdef CONFIG_BATMAN_ADV_DAT
atomic_set(&bat_priv->distributed_arp_table, 1);
#endif
#ifdef CONFIG_BATMAN_ADV_MCAST
bat_priv->mcast.querier_ipv4.exists = false;
bat_priv->mcast.querier_ipv4.shadowing = false;
bat_priv->mcast.querier_ipv6.exists = false;
bat_priv->mcast.querier_ipv6.shadowing = false;
bat_priv->mcast.flags = BATADV_NO_FLAGS;
atomic_set(&bat_priv->multicast_mode, 1);
atomic_set(&bat_priv->mcast.num_want_all_unsnoopables, 0);
batman-adv: Send multicast packets to nodes with a WANT_ALL flag With this patch a node sends IPv4 multicast packets to nodes which have a BATADV_MCAST_WANT_ALL_IPV4 flag set and IPv6 multicast packets to nodes which have a BATADV_MCAST_WANT_ALL_IPV6 flag set, too. Why is this needed? There are scenarios involving bridges where multicast report snooping and multicast TT announcements are not sufficient, which would lead to packet loss for some nodes otherwise: MLDv1 and IGMPv1/IGMPv2 have a suppression mechanism for multicast listener reports. When we have an MLDv1/IGMPv1/IGMPv2 querier behind a bridge then our snooping bridge is potentially not going to see any reports even though listeners exist because according to RFC4541 such reports are only forwarded to multicast routers: ----------------------------------------------------------- --------------- {Querier}---|Snoop. Switch|----{Listener} --------------- \ ^ ------- | br0 | < ??? ------- \ _-~---~_ _-~/ ~-_ ~ batman-adv \-----{Sender} \~_ cloud ~/ -~~__-__-~_/ I) MLDv1 Query: {Querier} -> flooded II) MLDv1 Report: {Listener} -> {Querier} -> br0 cannot detect the {Listener} => Packets from {Sender} need to be forwarded to all detected listeners and MLDv1/IGMPv1/IGMPv2 queriers. ----------------------------------------------------------- Note that we do not need to explicitly forward to MLDv2/IGMPv3 queriers, because these protocols have no report suppression: A bridge has no trouble detecting MLDv2/IGMPv3 listeners. Even though we do not support bridges yet we need to provide the according infrastructure already to not break compatibility later. Signed-off-by: Linus Lüssing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
2014-02-16 00:47:54 +08:00
atomic_set(&bat_priv->mcast.num_want_all_ipv4, 0);
atomic_set(&bat_priv->mcast.num_want_all_ipv6, 0);
#endif
atomic_set(&bat_priv->gw.mode, BATADV_GW_MODE_OFF);
atomic_set(&bat_priv->gw.bandwidth_down, 100);
atomic_set(&bat_priv->gw.bandwidth_up, 20);
atomic_set(&bat_priv->orig_interval, 1000);
atomic_set(&bat_priv->hop_penalty, 30);
#ifdef CONFIG_BATMAN_ADV_DEBUG
atomic_set(&bat_priv->log_level, 0);
#endif
atomic_set(&bat_priv->fragmentation, 1);
atomic_set(&bat_priv->packet_size_max, ETH_DATA_LEN);
atomic_set(&bat_priv->bcast_queue_left, BATADV_BCAST_QUEUE_LEN);
atomic_set(&bat_priv->batman_queue_left, BATADV_BATMAN_QUEUE_LEN);
atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
atomic_set(&bat_priv->bcast_seqno, 1);
atomic_set(&bat_priv->tt.vn, 0);
atomic_set(&bat_priv->tt.local_changes, 0);
atomic_set(&bat_priv->tt.ogm_append_cnt, 0);
#ifdef CONFIG_BATMAN_ADV_BLA
atomic_set(&bat_priv->bla.num_requests, 0);
#endif
atomic_set(&bat_priv->tp_num, 0);
bat_priv->tt.last_changeset = NULL;
bat_priv->tt.last_changeset_len = 0;
bat_priv->isolation_mark = 0;
bat_priv->isolation_mark_mask = 0;
/* randomize initial seqno to avoid collision */
get_random_bytes(&random_seqno, sizeof(random_seqno));
atomic_set(&bat_priv->frag_seqno, random_seqno);
bat_priv->primary_if = NULL;
batman-adv: network coding - add the initial infrastructure code Network coding exploits the 802.11 shared medium to allow multiple packets to be sent in a single transmission. In brief, a relay can XOR two packets, and send the coded packet to two destinations. The receivers can decode one of the original packets by XOR'ing the coded packet with the other original packet. This will lead to increased throughput in topologies where two packets cross one relay. In a simple topology with three nodes, it takes four transmissions without network coding to get one packet from Node A to Node B and one from Node B to Node A: 1. Node A ---- p1 ---> Node R Node B 2. Node A Node R <--- p2 ---- Node B 3. Node A <--- p2 ---- Node R Node B 4. Node A Node R ---- p1 ---> Node B With network coding, the relay only needs one transmission, which saves us one slot of valuable airtime: 1. Node A ---- p1 ---> Node R Node B 2. Node A Node R <--- p2 ---- Node B 3. Node A <- p1 x p2 - Node R - p1 x p2 -> Node B The same principle holds for a topology including five nodes. Here the packets from Node A and Node B are overheard by Node C and Node D, respectively. This allows Node R to send a network coded packet to save one transmission: Node A Node B | \ / | | p1 p2 | | \ / | p1 > Node R < p2 | | | / \ | | p1 x p2 p1 x p2 | v / \ v / \ Node C < > Node D More information is available on the open-mesh.org wiki[1]. This patch adds the initial code to support network coding in batman-adv. It sets up a worker thread to do house keeping and adds a sysfs file to enable/disable network coding. The feature is disabled by default, as it requires a wifi-driver with working promiscuous mode, and also because it adds a small delay at each hop. [1] http://www.open-mesh.org/projects/batman-adv/wiki/Catwoman Signed-off-by: Martin Hundebøll <martin@hundeboll.net> Signed-off-by: Marek Lindner <lindner_marek@yahoo.de> Signed-off-by: Antonio Quartulli <ordex@autistici.org>
2013-01-25 18:12:38 +08:00
batadv_nc_init_bat_priv(bat_priv);
ret = batadv_algo_select(bat_priv, batadv_routing_algo);
if (ret < 0)
goto free_bat_counters;
ret = batadv_debugfs_add_meshif(dev);
if (ret < 0)
goto free_bat_counters;
ret = batadv_mesh_init(dev);
if (ret < 0)
goto unreg_debugfs;
return 0;
unreg_debugfs:
batadv_debugfs_del_meshif(dev);
free_bat_counters:
free_percpu(bat_priv->bat_counters);
bat_priv->bat_counters = NULL;
return ret;
}
/**
* batadv_softif_slave_add() - Add a slave interface to a batadv_soft_interface
* @dev: batadv_soft_interface used as master interface
* @slave_dev: net_device which should become the slave interface
* @extack: extended ACK report struct
*
* Return: 0 if successful or error otherwise.
*/
static int batadv_softif_slave_add(struct net_device *dev,
struct net_device *slave_dev,
struct netlink_ext_ack *extack)
{
struct batadv_hard_iface *hard_iface;
struct net *net = dev_net(dev);
int ret = -EINVAL;
hard_iface = batadv_hardif_get_by_netdev(slave_dev);
if (!hard_iface || hard_iface->soft_iface)
goto out;
ret = batadv_hardif_enable_interface(hard_iface, net, dev->name);
out:
if (hard_iface)
batadv_hardif_put(hard_iface);
return ret;
}
/**
* batadv_softif_slave_del() - Delete a slave iface from a batadv_soft_interface
* @dev: batadv_soft_interface used as master interface
* @slave_dev: net_device which should be removed from the master interface
*
* Return: 0 if successful or error otherwise.
*/
static int batadv_softif_slave_del(struct net_device *dev,
struct net_device *slave_dev)
{
struct batadv_hard_iface *hard_iface;
int ret = -EINVAL;
hard_iface = batadv_hardif_get_by_netdev(slave_dev);
if (!hard_iface || hard_iface->soft_iface != dev)
goto out;
batadv_hardif_disable_interface(hard_iface, BATADV_IF_CLEANUP_KEEP);
ret = 0;
out:
if (hard_iface)
batadv_hardif_put(hard_iface);
return ret;
}
static const struct net_device_ops batadv_netdev_ops = {
.ndo_init = batadv_softif_init_late,
.ndo_open = batadv_interface_open,
.ndo_stop = batadv_interface_release,
.ndo_get_stats = batadv_interface_stats,
.ndo_vlan_rx_add_vid = batadv_interface_add_vid,
.ndo_vlan_rx_kill_vid = batadv_interface_kill_vid,
.ndo_set_mac_address = batadv_interface_set_mac_addr,
.ndo_change_mtu = batadv_interface_change_mtu,
.ndo_set_rx_mode = batadv_interface_set_rx_mode,
.ndo_start_xmit = batadv_interface_tx,
.ndo_validate_addr = eth_validate_addr,
.ndo_add_slave = batadv_softif_slave_add,
.ndo_del_slave = batadv_softif_slave_del,
};
static void batadv_get_drvinfo(struct net_device *dev,
struct ethtool_drvinfo *info)
{
strlcpy(info->driver, "B.A.T.M.A.N. advanced", sizeof(info->driver));
strlcpy(info->version, BATADV_SOURCE_VERSION, sizeof(info->version));
strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
strlcpy(info->bus_info, "batman", sizeof(info->bus_info));
}
/* Inspired by drivers/net/ethernet/dlink/sundance.c:1702
* Declare each description string in struct.name[] to get fixed sized buffer
* and compile time checking for strings longer than ETH_GSTRING_LEN.
*/
static const struct {
const char name[ETH_GSTRING_LEN];
} batadv_counters_strings[] = {
{ "tx" },
{ "tx_bytes" },
{ "tx_dropped" },
{ "rx" },
{ "rx_bytes" },
{ "forward" },
{ "forward_bytes" },
{ "mgmt_tx" },
{ "mgmt_tx_bytes" },
{ "mgmt_rx" },
{ "mgmt_rx_bytes" },
{ "frag_tx" },
{ "frag_tx_bytes" },
{ "frag_rx" },
{ "frag_rx_bytes" },
{ "frag_fwd" },
{ "frag_fwd_bytes" },
{ "tt_request_tx" },
{ "tt_request_rx" },
{ "tt_response_tx" },
{ "tt_response_rx" },
{ "tt_roam_adv_tx" },
{ "tt_roam_adv_rx" },
#ifdef CONFIG_BATMAN_ADV_DAT
{ "dat_get_tx" },
{ "dat_get_rx" },
{ "dat_put_tx" },
{ "dat_put_rx" },
{ "dat_cached_reply_tx" },
#endif
#ifdef CONFIG_BATMAN_ADV_NC
{ "nc_code" },
{ "nc_code_bytes" },
{ "nc_recode" },
{ "nc_recode_bytes" },
{ "nc_buffer" },
{ "nc_decode" },
{ "nc_decode_bytes" },
{ "nc_decode_failed" },
{ "nc_sniffed" },
#endif
};
static void batadv_get_strings(struct net_device *dev, u32 stringset, u8 *data)
{
if (stringset == ETH_SS_STATS)
memcpy(data, batadv_counters_strings,
sizeof(batadv_counters_strings));
}
static void batadv_get_ethtool_stats(struct net_device *dev,
struct ethtool_stats *stats, u64 *data)
{
struct batadv_priv *bat_priv = netdev_priv(dev);
int i;
for (i = 0; i < BATADV_CNT_NUM; i++)
data[i] = batadv_sum_counter(bat_priv, i);
}
static int batadv_get_sset_count(struct net_device *dev, int stringset)
{
if (stringset == ETH_SS_STATS)
return BATADV_CNT_NUM;
return -EOPNOTSUPP;
}
static const struct ethtool_ops batadv_ethtool_ops = {
.get_drvinfo = batadv_get_drvinfo,
.get_link = ethtool_op_get_link,
.get_strings = batadv_get_strings,
.get_ethtool_stats = batadv_get_ethtool_stats,
.get_sset_count = batadv_get_sset_count,
};
/**
* batadv_softif_free() - Deconstructor of batadv_soft_interface
* @dev: Device to cleanup and remove
*/
static void batadv_softif_free(struct net_device *dev)
{
batadv_debugfs_del_meshif(dev);
batadv_mesh_free(dev);
/* some scheduled RCU callbacks need the bat_priv struct to accomplish
* their tasks. Wait for them all to be finished before freeing the
* netdev and its private data (bat_priv)
*/
rcu_barrier();
}
/**
* batadv_softif_init_early() - early stage initialization of soft interface
* @dev: registered network device to modify
*/
static void batadv_softif_init_early(struct net_device *dev)
{
ether_setup(dev);
dev->netdev_ops = &batadv_netdev_ops;
net: Fix inconsistent teardown and release of private netdev state. Network devices can allocate reasources and private memory using netdev_ops->ndo_init(). However, the release of these resources can occur in one of two different places. Either netdev_ops->ndo_uninit() or netdev->destructor(). The decision of which operation frees the resources depends upon whether it is necessary for all netdev refs to be released before it is safe to perform the freeing. netdev_ops->ndo_uninit() presumably can occur right after the NETDEV_UNREGISTER notifier completes and the unicast and multicast address lists are flushed. netdev->destructor(), on the other hand, does not run until the netdev references all go away. Further complicating the situation is that netdev->destructor() almost universally does also a free_netdev(). This creates a problem for the logic in register_netdevice(). Because all callers of register_netdevice() manage the freeing of the netdev, and invoke free_netdev(dev) if register_netdevice() fails. If netdev_ops->ndo_init() succeeds, but something else fails inside of register_netdevice(), it does call ndo_ops->ndo_uninit(). But it is not able to invoke netdev->destructor(). This is because netdev->destructor() will do a free_netdev() and then the caller of register_netdevice() will do the same. However, this means that the resources that would normally be released by netdev->destructor() will not be. Over the years drivers have added local hacks to deal with this, by invoking their destructor parts by hand when register_netdevice() fails. Many drivers do not try to deal with this, and instead we have leaks. Let's close this hole by formalizing the distinction between what private things need to be freed up by netdev->destructor() and whether the driver needs unregister_netdevice() to perform the free_netdev(). netdev->priv_destructor() performs all actions to free up the private resources that used to be freed by netdev->destructor(), except for free_netdev(). netdev->needs_free_netdev is a boolean that indicates whether free_netdev() should be done at the end of unregister_netdevice(). Now, register_netdevice() can sanely release all resources after ndo_ops->ndo_init() succeeds, by invoking both ndo_ops->ndo_uninit() and netdev->priv_destructor(). And at the end of unregister_netdevice(), we invoke netdev->priv_destructor() and optionally call free_netdev(). Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-09 00:52:56 +08:00
dev->needs_free_netdev = true;
dev->priv_destructor = batadv_softif_free;
dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_NETNS_LOCAL;
dev->features |= NETIF_F_LLTX;
dev->priv_flags |= IFF_NO_QUEUE;
/* can't call min_mtu, because the needed variables
* have not been initialized yet
*/
dev->mtu = ETH_DATA_LEN;
/* generate random address */
eth_hw_addr_random(dev);
dev->ethtool_ops = &batadv_ethtool_ops;
}
/**
* batadv_softif_create() - Create and register soft interface
* @net: the applicable net namespace
* @name: name of the new soft interface
*
* Return: newly allocated soft_interface, NULL on errors
*/
struct net_device *batadv_softif_create(struct net *net, const char *name)
{
struct net_device *soft_iface;
int ret;
soft_iface = alloc_netdev(sizeof(struct batadv_priv), name,
NET_NAME_UNKNOWN, batadv_softif_init_early);
if (!soft_iface)
return NULL;
dev_net_set(soft_iface, net);
soft_iface->rtnl_link_ops = &batadv_link_ops;
ret = register_netdevice(soft_iface);
if (ret < 0) {
pr_err("Unable to register the batman interface '%s': %i\n",
name, ret);
free_netdev(soft_iface);
return NULL;
}
return soft_iface;
}
/**
* batadv_softif_destroy_sysfs() - deletion of batadv_soft_interface via sysfs
* @soft_iface: the to-be-removed batman-adv interface
*/
void batadv_softif_destroy_sysfs(struct net_device *soft_iface)
{
struct batadv_priv *bat_priv = netdev_priv(soft_iface);
struct batadv_softif_vlan *vlan;
ASSERT_RTNL();
/* destroy the "untagged" VLAN */
vlan = batadv_softif_vlan_get(bat_priv, BATADV_NO_FLAGS);
if (vlan) {
batadv_softif_destroy_vlan(bat_priv, vlan);
batadv_softif_vlan_put(vlan);
}
batadv_sysfs_del_meshif(soft_iface);
unregister_netdevice(soft_iface);
}
/**
* batadv_softif_destroy_netlink() - deletion of batadv_soft_interface via
* netlink
* @soft_iface: the to-be-removed batman-adv interface
* @head: list pointer
*/
static void batadv_softif_destroy_netlink(struct net_device *soft_iface,
struct list_head *head)
{
struct batadv_priv *bat_priv = netdev_priv(soft_iface);
struct batadv_hard_iface *hard_iface;
struct batadv_softif_vlan *vlan;
list_for_each_entry(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->soft_iface == soft_iface)
batadv_hardif_disable_interface(hard_iface,
BATADV_IF_CLEANUP_KEEP);
}
/* destroy the "untagged" VLAN */
vlan = batadv_softif_vlan_get(bat_priv, BATADV_NO_FLAGS);
if (vlan) {
batadv_softif_destroy_vlan(bat_priv, vlan);
batadv_softif_vlan_put(vlan);
}
batadv_sysfs_del_meshif(soft_iface);
unregister_netdevice_queue(soft_iface, head);
}
/**
* batadv_softif_is_valid() - Check whether device is a batadv soft interface
* @net_dev: device which should be checked
*
* Return: true when net_dev is a batman-adv interface, false otherwise
*/
bool batadv_softif_is_valid(const struct net_device *net_dev)
{
if (net_dev->netdev_ops->ndo_start_xmit == batadv_interface_tx)
return true;
return false;
}
struct rtnl_link_ops batadv_link_ops __read_mostly = {
.kind = "batadv",
.priv_size = sizeof(struct batadv_priv),
.setup = batadv_softif_init_early,
.dellink = batadv_softif_destroy_netlink,
};