linux/net/tipc/udp_media.c
Tommi Rantala c7799c067c tipc: call tipc_rcv() only if bearer is up in tipc_udp_recv()
Remove the second tipc_rcv() call in tipc_udp_recv(). We have just
checked that the bearer is not up, and calling tipc_rcv() with a bearer
that is not up leads to a TIPC div-by-zero crash in
tipc_node_calculate_timer(). The crash is rare in practice, but can
happen like this:

  We're enabling a bearer, but it's not yet up and fully initialized.
  At the same time we receive a discovery packet, and in tipc_udp_recv()
  we end up calling tipc_rcv() with the not-yet-initialized bearer,
  causing later the div-by-zero crash in tipc_node_calculate_timer().

Jon Maloy explains the impact of removing the second tipc_rcv() call:
  "link setup in the worst case will be delayed until the next arriving
   discovery messages, 1 sec later, and this is an acceptable delay."

As the tipc_rcv() call is removed, just leave the function via the
rcu_out label, so that we will kfree_skb().

[   12.590450] Own node address <1.1.1>, network identity 1
[   12.668088] divide error: 0000 [#1] SMP
[   12.676952] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.2-dirty #1
[   12.679225] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014
[   12.682095] task: ffff8c2a761edb80 task.stack: ffffa41cc0cac000
[   12.684087] RIP: 0010:tipc_node_calculate_timer.isra.12+0x45/0x60 [tipc]
[   12.686486] RSP: 0018:ffff8c2a7fc838a0 EFLAGS: 00010246
[   12.688451] RAX: 0000000000000000 RBX: ffff8c2a5b382600 RCX: 0000000000000000
[   12.691197] RDX: 0000000000000000 RSI: ffff8c2a5b382600 RDI: ffff8c2a5b382600
[   12.693945] RBP: ffff8c2a7fc838b0 R08: 0000000000000001 R09: 0000000000000001
[   12.696632] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8c2a5d8949d8
[   12.699491] R13: ffffffff95ede400 R14: 0000000000000000 R15: ffff8c2a5d894800
[   12.702338] FS:  0000000000000000(0000) GS:ffff8c2a7fc80000(0000) knlGS:0000000000000000
[   12.705099] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   12.706776] CR2: 0000000001bb9440 CR3: 00000000bd009001 CR4: 00000000003606e0
[   12.708847] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   12.711016] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   12.712627] Call Trace:
[   12.713390]  <IRQ>
[   12.714011]  tipc_node_check_dest+0x2e8/0x350 [tipc]
[   12.715286]  tipc_disc_rcv+0x14d/0x1d0 [tipc]
[   12.716370]  tipc_rcv+0x8b0/0xd40 [tipc]
[   12.717396]  ? minmax_running_min+0x2f/0x60
[   12.718248]  ? dst_alloc+0x4c/0xa0
[   12.718964]  ? tcp_ack+0xaf1/0x10b0
[   12.719658]  ? tipc_udp_is_known_peer+0xa0/0xa0 [tipc]
[   12.720634]  tipc_udp_recv+0x71/0x1d0 [tipc]
[   12.721459]  ? dst_alloc+0x4c/0xa0
[   12.722130]  udp_queue_rcv_skb+0x264/0x490
[   12.722924]  __udp4_lib_rcv+0x21e/0x990
[   12.723670]  ? ip_route_input_rcu+0x2dd/0xbf0
[   12.724442]  ? tcp_v4_rcv+0x958/0xa40
[   12.725039]  udp_rcv+0x1a/0x20
[   12.725587]  ip_local_deliver_finish+0x97/0x1d0
[   12.726323]  ip_local_deliver+0xaf/0xc0
[   12.726959]  ? ip_route_input_noref+0x19/0x20
[   12.727689]  ip_rcv_finish+0xdd/0x3b0
[   12.728307]  ip_rcv+0x2ac/0x360
[   12.728839]  __netif_receive_skb_core+0x6fb/0xa90
[   12.729580]  ? udp4_gro_receive+0x1a7/0x2c0
[   12.730274]  __netif_receive_skb+0x1d/0x60
[   12.730953]  ? __netif_receive_skb+0x1d/0x60
[   12.731637]  netif_receive_skb_internal+0x37/0xd0
[   12.732371]  napi_gro_receive+0xc7/0xf0
[   12.732920]  receive_buf+0x3c3/0xd40
[   12.733441]  virtnet_poll+0xb1/0x250
[   12.733944]  net_rx_action+0x23e/0x370
[   12.734476]  __do_softirq+0xc5/0x2f8
[   12.734922]  irq_exit+0xfa/0x100
[   12.735315]  do_IRQ+0x4f/0xd0
[   12.735680]  common_interrupt+0xa2/0xa2
[   12.736126]  </IRQ>
[   12.736416] RIP: 0010:native_safe_halt+0x6/0x10
[   12.736925] RSP: 0018:ffffa41cc0cafe90 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff4d
[   12.737756] RAX: 0000000000000000 RBX: ffff8c2a761edb80 RCX: 0000000000000000
[   12.738504] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[   12.739258] RBP: ffffa41cc0cafe90 R08: 0000014b5b9795e5 R09: ffffa41cc12c7e88
[   12.740118] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002
[   12.740964] R13: ffff8c2a761edb80 R14: 0000000000000000 R15: 0000000000000000
[   12.741831]  default_idle+0x2a/0x100
[   12.742323]  arch_cpu_idle+0xf/0x20
[   12.742796]  default_idle_call+0x28/0x40
[   12.743312]  do_idle+0x179/0x1f0
[   12.743761]  cpu_startup_entry+0x1d/0x20
[   12.744291]  start_secondary+0x112/0x120
[   12.744816]  secondary_startup_64+0xa5/0xa5
[   12.745367] Code: b9 f4 01 00 00 48 89 c2 48 c1 ea 02 48 3d d3 07 00
00 48 0f 47 d1 49 8b 0c 24 48 39 d1 76 07 49 89 14 24 48 89 d1 31 d2 48
89 df <48> f7 f1 89 c6 e8 81 6e ff ff 5b 41 5c 5d c3 66 90 66 2e 0f 1f
[   12.747527] RIP: tipc_node_calculate_timer.isra.12+0x45/0x60 [tipc] RSP: ffff8c2a7fc838a0
[   12.748555] ---[ end trace 1399ab83390650fd ]---
[   12.749296] Kernel panic - not syncing: Fatal exception in interrupt
[   12.750123] Kernel Offset: 0x13200000 from 0xffffffff82000000
(relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[   12.751215] Rebooting in 60 seconds..

Fixes: c9b64d492b ("tipc: add replicast peer discovery")
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-01 15:14:22 -05:00

796 lines
20 KiB
C

/* net/tipc/udp_media.c: IP bearer support for TIPC
*
* Copyright (c) 2015, Ericsson AB
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the names of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <linux/socket.h>
#include <linux/ip.h>
#include <linux/udp.h>
#include <linux/inet.h>
#include <linux/inetdevice.h>
#include <linux/igmp.h>
#include <linux/kernel.h>
#include <linux/workqueue.h>
#include <linux/list.h>
#include <net/sock.h>
#include <net/ip.h>
#include <net/udp_tunnel.h>
#include <net/addrconf.h>
#include <linux/tipc_netlink.h>
#include "core.h"
#include "bearer.h"
#include "netlink.h"
#include "msg.h"
/* IANA assigned UDP port */
#define UDP_PORT_DEFAULT 6118
#define UDP_MIN_HEADROOM 48
/**
* struct udp_media_addr - IP/UDP addressing information
*
* This is the bearer level originating address used in neighbor discovery
* messages, and all fields should be in network byte order
*/
struct udp_media_addr {
__be16 proto;
__be16 port;
union {
struct in_addr ipv4;
struct in6_addr ipv6;
};
};
/* struct udp_replicast - container for UDP remote addresses */
struct udp_replicast {
struct udp_media_addr addr;
struct rcu_head rcu;
struct list_head list;
};
/**
* struct udp_bearer - ip/udp bearer data structure
* @bearer: associated generic tipc bearer
* @ubsock: bearer associated socket
* @ifindex: local address scope
* @work: used to schedule deferred work on a bearer
*/
struct udp_bearer {
struct tipc_bearer __rcu *bearer;
struct socket *ubsock;
u32 ifindex;
struct work_struct work;
struct udp_replicast rcast;
};
static int tipc_udp_is_mcast_addr(struct udp_media_addr *addr)
{
if (ntohs(addr->proto) == ETH_P_IP)
return ipv4_is_multicast(addr->ipv4.s_addr);
#if IS_ENABLED(CONFIG_IPV6)
else
return ipv6_addr_is_multicast(&addr->ipv6);
#endif
return 0;
}
/* udp_media_addr_set - convert a ip/udp address to a TIPC media address */
static void tipc_udp_media_addr_set(struct tipc_media_addr *addr,
struct udp_media_addr *ua)
{
memset(addr, 0, sizeof(struct tipc_media_addr));
addr->media_id = TIPC_MEDIA_TYPE_UDP;
memcpy(addr->value, ua, sizeof(struct udp_media_addr));
if (tipc_udp_is_mcast_addr(ua))
addr->broadcast = TIPC_BROADCAST_SUPPORT;
}
/* tipc_udp_addr2str - convert ip/udp address to string */
static int tipc_udp_addr2str(struct tipc_media_addr *a, char *buf, int size)
{
struct udp_media_addr *ua = (struct udp_media_addr *)&a->value;
if (ntohs(ua->proto) == ETH_P_IP)
snprintf(buf, size, "%pI4:%u", &ua->ipv4, ntohs(ua->port));
else if (ntohs(ua->proto) == ETH_P_IPV6)
snprintf(buf, size, "%pI6:%u", &ua->ipv6, ntohs(ua->port));
else
pr_err("Invalid UDP media address\n");
return 0;
}
/* tipc_udp_msg2addr - extract an ip/udp address from a TIPC ndisc message */
static int tipc_udp_msg2addr(struct tipc_bearer *b, struct tipc_media_addr *a,
char *msg)
{
struct udp_media_addr *ua;
ua = (struct udp_media_addr *) (msg + TIPC_MEDIA_ADDR_OFFSET);
if (msg[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_UDP)
return -EINVAL;
tipc_udp_media_addr_set(a, ua);
return 0;
}
/* tipc_udp_addr2msg - write an ip/udp address to a TIPC ndisc message */
static int tipc_udp_addr2msg(char *msg, struct tipc_media_addr *a)
{
memset(msg, 0, TIPC_MEDIA_INFO_SIZE);
msg[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_UDP;
memcpy(msg + TIPC_MEDIA_ADDR_OFFSET, a->value,
sizeof(struct udp_media_addr));
return 0;
}
/* tipc_send_msg - enqueue a send request */
static int tipc_udp_xmit(struct net *net, struct sk_buff *skb,
struct udp_bearer *ub, struct udp_media_addr *src,
struct udp_media_addr *dst)
{
int ttl, err = 0;
struct rtable *rt;
if (dst->proto == htons(ETH_P_IP)) {
struct flowi4 fl = {
.daddr = dst->ipv4.s_addr,
.saddr = src->ipv4.s_addr,
.flowi4_mark = skb->mark,
.flowi4_proto = IPPROTO_UDP
};
rt = ip_route_output_key(net, &fl);
if (IS_ERR(rt)) {
err = PTR_ERR(rt);
goto tx_error;
}
skb->dev = rt->dst.dev;
ttl = ip4_dst_hoplimit(&rt->dst);
udp_tunnel_xmit_skb(rt, ub->ubsock->sk, skb, src->ipv4.s_addr,
dst->ipv4.s_addr, 0, ttl, 0, src->port,
dst->port, false, true);
#if IS_ENABLED(CONFIG_IPV6)
} else {
struct dst_entry *ndst;
struct flowi6 fl6 = {
.flowi6_oif = ub->ifindex,
.daddr = dst->ipv6,
.saddr = src->ipv6,
.flowi6_proto = IPPROTO_UDP
};
err = ipv6_stub->ipv6_dst_lookup(net, ub->ubsock->sk, &ndst,
&fl6);
if (err)
goto tx_error;
ttl = ip6_dst_hoplimit(ndst);
err = udp_tunnel6_xmit_skb(ndst, ub->ubsock->sk, skb,
ndst->dev, &src->ipv6,
&dst->ipv6, 0, ttl, 0, src->port,
dst->port, false);
#endif
}
return err;
tx_error:
kfree_skb(skb);
return err;
}
static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb,
struct tipc_bearer *b,
struct tipc_media_addr *addr)
{
struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
struct udp_media_addr *dst = (struct udp_media_addr *)&addr->value;
struct udp_replicast *rcast;
struct udp_bearer *ub;
int err = 0;
if (skb_headroom(skb) < UDP_MIN_HEADROOM) {
err = pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC);
if (err)
goto out;
}
skb_set_inner_protocol(skb, htons(ETH_P_TIPC));
ub = rcu_dereference_rtnl(b->media_ptr);
if (!ub) {
err = -ENODEV;
goto out;
}
if (addr->broadcast != TIPC_REPLICAST_SUPPORT)
return tipc_udp_xmit(net, skb, ub, src, dst);
/* Replicast, send an skb to each configured IP address */
list_for_each_entry_rcu(rcast, &ub->rcast.list, list) {
struct sk_buff *_skb;
_skb = pskb_copy(skb, GFP_ATOMIC);
if (!_skb) {
err = -ENOMEM;
goto out;
}
err = tipc_udp_xmit(net, _skb, ub, src, &rcast->addr);
if (err) {
kfree_skb(_skb);
goto out;
}
}
err = 0;
out:
kfree_skb(skb);
return err;
}
static bool tipc_udp_is_known_peer(struct tipc_bearer *b,
struct udp_media_addr *addr)
{
struct udp_replicast *rcast, *tmp;
struct udp_bearer *ub;
ub = rcu_dereference_rtnl(b->media_ptr);
if (!ub) {
pr_err_ratelimited("UDP bearer instance not found\n");
return false;
}
list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
if (!memcmp(&rcast->addr, addr, sizeof(struct udp_media_addr)))
return true;
}
return false;
}
static int tipc_udp_rcast_add(struct tipc_bearer *b,
struct udp_media_addr *addr)
{
struct udp_replicast *rcast;
struct udp_bearer *ub;
ub = rcu_dereference_rtnl(b->media_ptr);
if (!ub)
return -ENODEV;
rcast = kmalloc(sizeof(*rcast), GFP_ATOMIC);
if (!rcast)
return -ENOMEM;
memcpy(&rcast->addr, addr, sizeof(struct udp_media_addr));
if (ntohs(addr->proto) == ETH_P_IP)
pr_info("New replicast peer: %pI4\n", &rcast->addr.ipv4);
#if IS_ENABLED(CONFIG_IPV6)
else if (ntohs(addr->proto) == ETH_P_IPV6)
pr_info("New replicast peer: %pI6\n", &rcast->addr.ipv6);
#endif
b->bcast_addr.broadcast = TIPC_REPLICAST_SUPPORT;
list_add_rcu(&rcast->list, &ub->rcast.list);
return 0;
}
static int tipc_udp_rcast_disc(struct tipc_bearer *b, struct sk_buff *skb)
{
struct udp_media_addr src = {0};
struct udp_media_addr *dst;
dst = (struct udp_media_addr *)&b->bcast_addr.value;
if (tipc_udp_is_mcast_addr(dst))
return 0;
src.port = udp_hdr(skb)->source;
if (ip_hdr(skb)->version == 4) {
struct iphdr *iphdr = ip_hdr(skb);
src.proto = htons(ETH_P_IP);
src.ipv4.s_addr = iphdr->saddr;
if (ipv4_is_multicast(iphdr->daddr))
return 0;
#if IS_ENABLED(CONFIG_IPV6)
} else if (ip_hdr(skb)->version == 6) {
struct ipv6hdr *iphdr = ipv6_hdr(skb);
src.proto = htons(ETH_P_IPV6);
src.ipv6 = iphdr->saddr;
if (ipv6_addr_is_multicast(&iphdr->daddr))
return 0;
#endif
} else {
return 0;
}
if (likely(tipc_udp_is_known_peer(b, &src)))
return 0;
return tipc_udp_rcast_add(b, &src);
}
/* tipc_udp_recv - read data from bearer socket */
static int tipc_udp_recv(struct sock *sk, struct sk_buff *skb)
{
struct udp_bearer *ub;
struct tipc_bearer *b;
struct tipc_msg *hdr;
int err;
ub = rcu_dereference_sk_user_data(sk);
if (!ub) {
pr_err_ratelimited("Failed to get UDP bearer reference");
goto out;
}
skb_pull(skb, sizeof(struct udphdr));
hdr = buf_msg(skb);
rcu_read_lock();
b = rcu_dereference_rtnl(ub->bearer);
if (!b)
goto rcu_out;
if (b && test_bit(0, &b->up)) {
tipc_rcv(sock_net(sk), skb, b);
rcu_read_unlock();
return 0;
}
if (unlikely(msg_user(hdr) == LINK_CONFIG)) {
err = tipc_udp_rcast_disc(b, skb);
if (err)
goto rcu_out;
}
rcu_out:
rcu_read_unlock();
out:
kfree_skb(skb);
return 0;
}
static int enable_mcast(struct udp_bearer *ub, struct udp_media_addr *remote)
{
int err = 0;
struct ip_mreqn mreqn;
struct sock *sk = ub->ubsock->sk;
if (ntohs(remote->proto) == ETH_P_IP) {
mreqn.imr_multiaddr = remote->ipv4;
mreqn.imr_ifindex = ub->ifindex;
err = ip_mc_join_group(sk, &mreqn);
#if IS_ENABLED(CONFIG_IPV6)
} else {
err = ipv6_stub->ipv6_sock_mc_join(sk, ub->ifindex,
&remote->ipv6);
#endif
}
return err;
}
static int __tipc_nl_add_udp_addr(struct sk_buff *skb,
struct udp_media_addr *addr, int nla_t)
{
if (ntohs(addr->proto) == ETH_P_IP) {
struct sockaddr_in ip4;
memset(&ip4, 0, sizeof(ip4));
ip4.sin_family = AF_INET;
ip4.sin_port = addr->port;
ip4.sin_addr.s_addr = addr->ipv4.s_addr;
if (nla_put(skb, nla_t, sizeof(ip4), &ip4))
return -EMSGSIZE;
#if IS_ENABLED(CONFIG_IPV6)
} else if (ntohs(addr->proto) == ETH_P_IPV6) {
struct sockaddr_in6 ip6;
memset(&ip6, 0, sizeof(ip6));
ip6.sin6_family = AF_INET6;
ip6.sin6_port = addr->port;
memcpy(&ip6.sin6_addr, &addr->ipv6, sizeof(struct in6_addr));
if (nla_put(skb, nla_t, sizeof(ip6), &ip6))
return -EMSGSIZE;
#endif
}
return 0;
}
int tipc_udp_nl_dump_remoteip(struct sk_buff *skb, struct netlink_callback *cb)
{
u32 bid = cb->args[0];
u32 skip_cnt = cb->args[1];
u32 portid = NETLINK_CB(cb->skb).portid;
struct udp_replicast *rcast, *tmp;
struct tipc_bearer *b;
struct udp_bearer *ub;
void *hdr;
int err;
int i;
if (!bid && !skip_cnt) {
struct net *net = sock_net(skb->sk);
struct nlattr *battrs[TIPC_NLA_BEARER_MAX + 1];
struct nlattr **attrs;
char *bname;
err = tipc_nlmsg_parse(cb->nlh, &attrs);
if (err)
return err;
if (!attrs[TIPC_NLA_BEARER])
return -EINVAL;
err = nla_parse_nested(battrs, TIPC_NLA_BEARER_MAX,
attrs[TIPC_NLA_BEARER],
tipc_nl_bearer_policy, NULL);
if (err)
return err;
if (!battrs[TIPC_NLA_BEARER_NAME])
return -EINVAL;
bname = nla_data(battrs[TIPC_NLA_BEARER_NAME]);
rtnl_lock();
b = tipc_bearer_find(net, bname);
if (!b) {
rtnl_unlock();
return -EINVAL;
}
bid = b->identity;
} else {
struct net *net = sock_net(skb->sk);
struct tipc_net *tn = net_generic(net, tipc_net_id);
rtnl_lock();
b = rtnl_dereference(tn->bearer_list[bid]);
if (!b) {
rtnl_unlock();
return -EINVAL;
}
}
ub = rcu_dereference_rtnl(b->media_ptr);
if (!ub) {
rtnl_unlock();
return -EINVAL;
}
i = 0;
list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
if (i < skip_cnt)
goto count;
hdr = genlmsg_put(skb, portid, cb->nlh->nlmsg_seq,
&tipc_genl_family, NLM_F_MULTI,
TIPC_NL_BEARER_GET);
if (!hdr)
goto done;
err = __tipc_nl_add_udp_addr(skb, &rcast->addr,
TIPC_NLA_UDP_REMOTE);
if (err) {
genlmsg_cancel(skb, hdr);
goto done;
}
genlmsg_end(skb, hdr);
count:
i++;
}
done:
rtnl_unlock();
cb->args[0] = bid;
cb->args[1] = i;
return skb->len;
}
int tipc_udp_nl_add_bearer_data(struct tipc_nl_msg *msg, struct tipc_bearer *b)
{
struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
struct udp_media_addr *dst;
struct udp_bearer *ub;
struct nlattr *nest;
ub = rcu_dereference_rtnl(b->media_ptr);
if (!ub)
return -ENODEV;
nest = nla_nest_start(msg->skb, TIPC_NLA_BEARER_UDP_OPTS);
if (!nest)
goto msg_full;
if (__tipc_nl_add_udp_addr(msg->skb, src, TIPC_NLA_UDP_LOCAL))
goto msg_full;
dst = (struct udp_media_addr *)&b->bcast_addr.value;
if (__tipc_nl_add_udp_addr(msg->skb, dst, TIPC_NLA_UDP_REMOTE))
goto msg_full;
if (!list_empty(&ub->rcast.list)) {
if (nla_put_flag(msg->skb, TIPC_NLA_UDP_MULTI_REMOTEIP))
goto msg_full;
}
nla_nest_end(msg->skb, nest);
return 0;
msg_full:
nla_nest_cancel(msg->skb, nest);
return -EMSGSIZE;
}
/**
* tipc_parse_udp_addr - build udp media address from netlink data
* @nlattr: netlink attribute containing sockaddr storage aligned address
* @addr: tipc media address to fill with address, port and protocol type
* @scope_id: IPv6 scope id pointer, not NULL indicates it's required
*/
static int tipc_parse_udp_addr(struct nlattr *nla, struct udp_media_addr *addr,
u32 *scope_id)
{
struct sockaddr_storage sa;
nla_memcpy(&sa, nla, sizeof(sa));
if (sa.ss_family == AF_INET) {
struct sockaddr_in *ip4 = (struct sockaddr_in *)&sa;
addr->proto = htons(ETH_P_IP);
addr->port = ip4->sin_port;
addr->ipv4.s_addr = ip4->sin_addr.s_addr;
return 0;
#if IS_ENABLED(CONFIG_IPV6)
} else if (sa.ss_family == AF_INET6) {
struct sockaddr_in6 *ip6 = (struct sockaddr_in6 *)&sa;
addr->proto = htons(ETH_P_IPV6);
addr->port = ip6->sin6_port;
memcpy(&addr->ipv6, &ip6->sin6_addr, sizeof(struct in6_addr));
/* Scope ID is only interesting for local addresses */
if (scope_id) {
int atype;
atype = ipv6_addr_type(&ip6->sin6_addr);
if (__ipv6_addr_needs_scope_id(atype) &&
!ip6->sin6_scope_id) {
return -EINVAL;
}
*scope_id = ip6->sin6_scope_id ? : 0;
}
return 0;
#endif
}
return -EADDRNOTAVAIL;
}
int tipc_udp_nl_bearer_add(struct tipc_bearer *b, struct nlattr *attr)
{
int err;
struct udp_media_addr addr = {0};
struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
struct udp_media_addr *dst;
if (nla_parse_nested(opts, TIPC_NLA_UDP_MAX, attr,
tipc_nl_udp_policy, NULL))
return -EINVAL;
if (!opts[TIPC_NLA_UDP_REMOTE])
return -EINVAL;
err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &addr, NULL);
if (err)
return err;
dst = (struct udp_media_addr *)&b->bcast_addr.value;
if (tipc_udp_is_mcast_addr(dst)) {
pr_err("Can't add remote ip to TIPC UDP multicast bearer\n");
return -EINVAL;
}
if (tipc_udp_is_known_peer(b, &addr))
return 0;
return tipc_udp_rcast_add(b, &addr);
}
/**
* tipc_udp_enable - callback to create a new udp bearer instance
* @net: network namespace
* @b: pointer to generic tipc_bearer
* @attrs: netlink bearer configuration
*
* validate the bearer parameters and initialize the udp bearer
* rtnl_lock should be held
*/
static int tipc_udp_enable(struct net *net, struct tipc_bearer *b,
struct nlattr *attrs[])
{
int err = -EINVAL;
struct udp_bearer *ub;
struct udp_media_addr remote = {0};
struct udp_media_addr local = {0};
struct udp_port_cfg udp_conf = {0};
struct udp_tunnel_sock_cfg tuncfg = {NULL};
struct nlattr *opts[TIPC_NLA_UDP_MAX + 1];
ub = kzalloc(sizeof(*ub), GFP_ATOMIC);
if (!ub)
return -ENOMEM;
INIT_LIST_HEAD(&ub->rcast.list);
if (!attrs[TIPC_NLA_BEARER_UDP_OPTS])
goto err;
if (nla_parse_nested(opts, TIPC_NLA_UDP_MAX,
attrs[TIPC_NLA_BEARER_UDP_OPTS],
tipc_nl_udp_policy, NULL))
goto err;
if (!opts[TIPC_NLA_UDP_LOCAL] || !opts[TIPC_NLA_UDP_REMOTE]) {
pr_err("Invalid UDP bearer configuration");
err = -EINVAL;
goto err;
}
err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_LOCAL], &local,
&ub->ifindex);
if (err)
goto err;
err = tipc_parse_udp_addr(opts[TIPC_NLA_UDP_REMOTE], &remote, NULL);
if (err)
goto err;
b->bcast_addr.media_id = TIPC_MEDIA_TYPE_UDP;
b->bcast_addr.broadcast = TIPC_BROADCAST_SUPPORT;
rcu_assign_pointer(b->media_ptr, ub);
rcu_assign_pointer(ub->bearer, b);
tipc_udp_media_addr_set(&b->addr, &local);
if (local.proto == htons(ETH_P_IP)) {
struct net_device *dev;
dev = __ip_dev_find(net, local.ipv4.s_addr, false);
if (!dev) {
err = -ENODEV;
goto err;
}
udp_conf.family = AF_INET;
udp_conf.local_ip.s_addr = htonl(INADDR_ANY);
udp_conf.use_udp_checksums = false;
ub->ifindex = dev->ifindex;
if (tipc_mtu_bad(dev, sizeof(struct iphdr) +
sizeof(struct udphdr))) {
err = -EINVAL;
goto err;
}
b->mtu = dev->mtu - sizeof(struct iphdr)
- sizeof(struct udphdr);
#if IS_ENABLED(CONFIG_IPV6)
} else if (local.proto == htons(ETH_P_IPV6)) {
udp_conf.family = AF_INET6;
udp_conf.use_udp6_tx_checksums = true;
udp_conf.use_udp6_rx_checksums = true;
udp_conf.local_ip6 = in6addr_any;
b->mtu = 1280;
#endif
} else {
err = -EAFNOSUPPORT;
goto err;
}
udp_conf.local_udp_port = local.port;
err = udp_sock_create(net, &udp_conf, &ub->ubsock);
if (err)
goto err;
tuncfg.sk_user_data = ub;
tuncfg.encap_type = 1;
tuncfg.encap_rcv = tipc_udp_recv;
tuncfg.encap_destroy = NULL;
setup_udp_tunnel_sock(net, ub->ubsock, &tuncfg);
/**
* The bcast media address port is used for all peers and the ip
* is used if it's a multicast address.
*/
memcpy(&b->bcast_addr.value, &remote, sizeof(remote));
if (tipc_udp_is_mcast_addr(&remote))
err = enable_mcast(ub, &remote);
else
err = tipc_udp_rcast_add(b, &remote);
if (err)
goto err;
return 0;
err:
if (ub->ubsock)
udp_tunnel_sock_release(ub->ubsock);
kfree(ub);
return err;
}
/* cleanup_bearer - break the socket/bearer association */
static void cleanup_bearer(struct work_struct *work)
{
struct udp_bearer *ub = container_of(work, struct udp_bearer, work);
struct udp_replicast *rcast, *tmp;
list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
list_del_rcu(&rcast->list);
kfree_rcu(rcast, rcu);
}
if (ub->ubsock)
udp_tunnel_sock_release(ub->ubsock);
synchronize_net();
kfree(ub);
}
/* tipc_udp_disable - detach bearer from socket */
static void tipc_udp_disable(struct tipc_bearer *b)
{
struct udp_bearer *ub;
ub = rcu_dereference_rtnl(b->media_ptr);
if (!ub) {
pr_err("UDP bearer instance not found\n");
return;
}
if (ub->ubsock)
sock_set_flag(ub->ubsock->sk, SOCK_DEAD);
RCU_INIT_POINTER(ub->bearer, NULL);
/* sock_release need to be done outside of rtnl lock */
INIT_WORK(&ub->work, cleanup_bearer);
schedule_work(&ub->work);
}
struct tipc_media udp_media_info = {
.send_msg = tipc_udp_send_msg,
.enable_media = tipc_udp_enable,
.disable_media = tipc_udp_disable,
.addr2str = tipc_udp_addr2str,
.addr2msg = tipc_udp_addr2msg,
.msg2addr = tipc_udp_msg2addr,
.priority = TIPC_DEF_LINK_PRI,
.tolerance = TIPC_DEF_LINK_TOL,
.window = TIPC_DEF_LINK_WIN,
.type_id = TIPC_MEDIA_TYPE_UDP,
.hwaddr_len = 0,
.name = "udp"
};