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![Vladimir Oltean](/assets/img/avatar_default.png)
According to the synchronization rules for .ndo_get_stats() as seen in
Documentation/networking/netdevices.rst, acquiring a plain spin_lock()
should not be illegal, but the bridge driver implementation makes it so.
After running these commands, I am being faced with the following
lockdep splat:
$ ip link add link swp0 name macsec0 type macsec encrypt on && ip link set swp0 up
$ ip link add dev br0 type bridge vlan_filtering 1 && ip link set br0 up
$ ip link set macsec0 master br0 && ip link set macsec0 up
========================================================
WARNING: possible irq lock inversion dependency detected
6.4.0-04295-g31b577b4bd4a #603 Not tainted
--------------------------------------------------------
swapper/1/0 just changed the state of lock:
ffff6bd348724cd8 (&br->lock){+.-.}-{3:3}, at: br_forward_delay_timer_expired+0x34/0x198
but this lock took another, SOFTIRQ-unsafe lock in the past:
(&ocelot->stats_lock){+.+.}-{3:3}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Chain exists of:
&br->lock --> &br->hash_lock --> &ocelot->stats_lock
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&ocelot->stats_lock);
local_irq_disable();
lock(&br->lock);
lock(&br->hash_lock);
<Interrupt>
lock(&br->lock);
*** DEADLOCK ***
(details about the 3 locks skipped)
swp0 is instantiated by drivers/net/dsa/ocelot/felix.c, and this
only matters to the extent that its .ndo_get_stats64() method calls
spin_lock(&ocelot->stats_lock).
Documentation/locking/lockdep-design.rst says:
| A lock is irq-safe means it was ever used in an irq context, while a lock
| is irq-unsafe means it was ever acquired with irq enabled.
(...)
| Furthermore, the following usage based lock dependencies are not allowed
| between any two lock-classes::
|
| <hardirq-safe> -> <hardirq-unsafe>
| <softirq-safe> -> <softirq-unsafe>
Lockdep marks br->hash_lock as softirq-safe, because it is sometimes
taken in softirq context (for example br_fdb_update() which runs in
NET_RX softirq), and when it's not in softirq context it blocks softirqs
by using spin_lock_bh().
Lockdep marks ocelot->stats_lock as softirq-unsafe, because it never
blocks softirqs from running, and it is never taken from softirq
context. So it can always be interrupted by softirqs.
There is a call path through which a function that holds br->hash_lock:
fdb_add_hw_addr() will call a function that acquires ocelot->stats_lock:
ocelot_port_get_stats64(). This can be seen below:
ocelot_port_get_stats64+0x3c/0x1e0
felix_get_stats64+0x20/0x38
dsa_slave_get_stats64+0x3c/0x60
dev_get_stats+0x74/0x2c8
rtnl_fill_stats+0x4c/0x150
rtnl_fill_ifinfo+0x5cc/0x7b8
rtmsg_ifinfo_build_skb+0xe4/0x150
rtmsg_ifinfo+0x5c/0xb0
__dev_notify_flags+0x58/0x200
__dev_set_promiscuity+0xa0/0x1f8
dev_set_promiscuity+0x30/0x70
macsec_dev_change_rx_flags+0x68/0x88
__dev_set_promiscuity+0x1a8/0x1f8
__dev_set_rx_mode+0x74/0xa8
dev_uc_add+0x74/0xa0
fdb_add_hw_addr+0x68/0xd8
fdb_add_local+0xc4/0x110
br_fdb_add_local+0x54/0x88
br_add_if+0x338/0x4a0
br_add_slave+0x20/0x38
do_setlink+0x3a4/0xcb8
rtnl_newlink+0x758/0x9d0
rtnetlink_rcv_msg+0x2f0/0x550
netlink_rcv_skb+0x128/0x148
rtnetlink_rcv+0x24/0x38
the plain English explanation for it is:
The macsec0 bridge port is created without p->flags & BR_PROMISC,
because it is what br_manage_promisc() decides for a VLAN filtering
bridge with a single auto port.
As part of the br_add_if() procedure, br_fdb_add_local() is called for
the MAC address of the device, and this results in a call to
dev_uc_add() for macsec0 while the softirq-safe br->hash_lock is taken.
Because macsec0 does not have IFF_UNICAST_FLT, dev_uc_add() ends up
calling __dev_set_promiscuity() for macsec0, which is propagated by its
implementation, macsec_dev_change_rx_flags(), to the lower device: swp0.
This triggers the call path:
dev_set_promiscuity(swp0)
-> rtmsg_ifinfo()
-> dev_get_stats()
-> ocelot_port_get_stats64()
with a calling context that lockdep doesn't like (br->hash_lock held).
Normally we don't see this, because even though many drivers that can be
bridge ports don't support IFF_UNICAST_FLT, we need a driver that
(a) doesn't support IFF_UNICAST_FLT, *and*
(b) it forwards the IFF_PROMISC flag to another driver, and
(c) *that* driver implements ndo_get_stats64() using a softirq-unsafe
spinlock.
Condition (b) is necessary because the first __dev_set_rx_mode() calls
__dev_set_promiscuity() with "bool notify=false", and thus, the
rtmsg_ifinfo() code path won't be entered.
The same criteria also hold true for DSA switches which don't report
IFF_UNICAST_FLT. When the DSA master uses a spin_lock() in its
ndo_get_stats64() method, the same lockdep splat can be seen.
I think the deadlock possibility is real, even though I didn't reproduce
it, and I'm thinking of the following situation to support that claim:
fdb_add_hw_addr() runs on a CPU A, in a context with softirqs locally
disabled and br->hash_lock held, and may end up attempting to acquire
ocelot->stats_lock.
In parallel, ocelot->stats_lock is currently held by a thread B (say,
ocelot_check_stats_work()), which is interrupted while holding it by a
softirq which attempts to lock br->hash_lock.
Thread B cannot make progress because br->hash_lock is held by A. Whereas
thread A cannot make progress because ocelot->stats_lock is held by B.
When taking the issue at face value, the bridge can avoid that problem
by simply making the ports promiscuous from a code path with a saner
calling context (br->hash_lock not held). A bridge port without
IFF_UNICAST_FLT is going to become promiscuous as soon as we call
dev_uc_add() on it (which we do unconditionally), so why not be
preemptive and make it promiscuous right from the beginning, so as to
not be taken by surprise.
With this, we've broken the links between code that holds br->hash_lock
or br->lock and code that calls into the ndo_change_rx_flags() or
ndo_get_stats64() ops of the bridge port.
Fixes: 2796d0c648
("bridge: Automatically manage port promiscuous mode.")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
777 lines
18 KiB
C
777 lines
18 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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* Userspace interface
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* Linux ethernet bridge
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*
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* Authors:
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* Lennert Buytenhek <buytenh@gnu.org>
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*/
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#include <linux/kernel.h>
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#include <linux/netdevice.h>
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#include <linux/etherdevice.h>
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#include <linux/netpoll.h>
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#include <linux/ethtool.h>
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#include <linux/if_arp.h>
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#include <linux/module.h>
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#include <linux/init.h>
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#include <linux/rtnetlink.h>
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#include <linux/if_ether.h>
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#include <linux/slab.h>
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#include <net/dsa.h>
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#include <net/sock.h>
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#include <linux/if_vlan.h>
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#include <net/switchdev.h>
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#include <net/net_namespace.h>
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#include "br_private.h"
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/*
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* Determine initial path cost based on speed.
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* using recommendations from 802.1d standard
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*
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* Since driver might sleep need to not be holding any locks.
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*/
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static int port_cost(struct net_device *dev)
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{
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struct ethtool_link_ksettings ecmd;
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if (!__ethtool_get_link_ksettings(dev, &ecmd)) {
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switch (ecmd.base.speed) {
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case SPEED_10000:
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return 2;
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case SPEED_5000:
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return 3;
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case SPEED_2500:
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return 4;
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case SPEED_1000:
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return 5;
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case SPEED_100:
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return 19;
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case SPEED_10:
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return 100;
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case SPEED_UNKNOWN:
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return 100;
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default:
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if (ecmd.base.speed > SPEED_10000)
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return 1;
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}
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}
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/* Old silly heuristics based on name */
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if (!strncmp(dev->name, "lec", 3))
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return 7;
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if (!strncmp(dev->name, "plip", 4))
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return 2500;
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return 100; /* assume old 10Mbps */
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}
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/* Check for port carrier transitions. */
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void br_port_carrier_check(struct net_bridge_port *p, bool *notified)
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{
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struct net_device *dev = p->dev;
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struct net_bridge *br = p->br;
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if (!(p->flags & BR_ADMIN_COST) &&
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netif_running(dev) && netif_oper_up(dev))
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p->path_cost = port_cost(dev);
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*notified = false;
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if (!netif_running(br->dev))
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return;
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spin_lock_bh(&br->lock);
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if (netif_running(dev) && netif_oper_up(dev)) {
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if (p->state == BR_STATE_DISABLED) {
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br_stp_enable_port(p);
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*notified = true;
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}
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} else {
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if (p->state != BR_STATE_DISABLED) {
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br_stp_disable_port(p);
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*notified = true;
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}
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}
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spin_unlock_bh(&br->lock);
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}
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static void br_port_set_promisc(struct net_bridge_port *p)
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{
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int err = 0;
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if (br_promisc_port(p))
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return;
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err = dev_set_promiscuity(p->dev, 1);
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if (err)
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return;
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br_fdb_unsync_static(p->br, p);
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p->flags |= BR_PROMISC;
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}
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static void br_port_clear_promisc(struct net_bridge_port *p)
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{
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int err;
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/* Check if the port is already non-promisc or if it doesn't
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* support UNICAST filtering. Without unicast filtering support
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* we'll end up re-enabling promisc mode anyway, so just check for
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* it here.
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*/
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if (!br_promisc_port(p) || !(p->dev->priv_flags & IFF_UNICAST_FLT))
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return;
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/* Since we'll be clearing the promisc mode, program the port
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* first so that we don't have interruption in traffic.
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*/
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err = br_fdb_sync_static(p->br, p);
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if (err)
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return;
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dev_set_promiscuity(p->dev, -1);
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p->flags &= ~BR_PROMISC;
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}
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/* When a port is added or removed or when certain port flags
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* change, this function is called to automatically manage
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* promiscuity setting of all the bridge ports. We are always called
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* under RTNL so can skip using rcu primitives.
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*/
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void br_manage_promisc(struct net_bridge *br)
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{
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struct net_bridge_port *p;
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bool set_all = false;
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/* If vlan filtering is disabled or bridge interface is placed
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* into promiscuous mode, place all ports in promiscuous mode.
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*/
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if ((br->dev->flags & IFF_PROMISC) || !br_vlan_enabled(br->dev))
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set_all = true;
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list_for_each_entry(p, &br->port_list, list) {
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if (set_all) {
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br_port_set_promisc(p);
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} else {
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/* If the number of auto-ports is <= 1, then all other
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* ports will have their output configuration
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* statically specified through fdbs. Since ingress
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* on the auto-port becomes forwarding/egress to other
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* ports and egress configuration is statically known,
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* we can say that ingress configuration of the
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* auto-port is also statically known.
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* This lets us disable promiscuous mode and write
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* this config to hw.
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*/
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if ((p->dev->priv_flags & IFF_UNICAST_FLT) &&
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(br->auto_cnt == 0 ||
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(br->auto_cnt == 1 && br_auto_port(p))))
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br_port_clear_promisc(p);
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else
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br_port_set_promisc(p);
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}
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}
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}
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int nbp_backup_change(struct net_bridge_port *p,
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struct net_device *backup_dev)
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{
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struct net_bridge_port *old_backup = rtnl_dereference(p->backup_port);
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struct net_bridge_port *backup_p = NULL;
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ASSERT_RTNL();
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if (backup_dev) {
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if (!netif_is_bridge_port(backup_dev))
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return -ENOENT;
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backup_p = br_port_get_rtnl(backup_dev);
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if (backup_p->br != p->br)
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return -EINVAL;
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}
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if (p == backup_p)
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return -EINVAL;
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if (old_backup == backup_p)
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return 0;
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/* if the backup link is already set, clear it */
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if (old_backup)
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old_backup->backup_redirected_cnt--;
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if (backup_p)
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backup_p->backup_redirected_cnt++;
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rcu_assign_pointer(p->backup_port, backup_p);
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return 0;
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}
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static void nbp_backup_clear(struct net_bridge_port *p)
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{
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nbp_backup_change(p, NULL);
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if (p->backup_redirected_cnt) {
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struct net_bridge_port *cur_p;
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list_for_each_entry(cur_p, &p->br->port_list, list) {
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struct net_bridge_port *backup_p;
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backup_p = rtnl_dereference(cur_p->backup_port);
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if (backup_p == p)
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nbp_backup_change(cur_p, NULL);
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}
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}
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WARN_ON(rcu_access_pointer(p->backup_port) || p->backup_redirected_cnt);
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}
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static void nbp_update_port_count(struct net_bridge *br)
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{
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struct net_bridge_port *p;
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u32 cnt = 0;
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list_for_each_entry(p, &br->port_list, list) {
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if (br_auto_port(p))
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cnt++;
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}
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if (br->auto_cnt != cnt) {
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br->auto_cnt = cnt;
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br_manage_promisc(br);
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}
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}
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static void nbp_delete_promisc(struct net_bridge_port *p)
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{
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/* If port is currently promiscuous, unset promiscuity.
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* Otherwise, it is a static port so remove all addresses
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* from it.
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*/
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dev_set_allmulti(p->dev, -1);
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if (br_promisc_port(p))
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dev_set_promiscuity(p->dev, -1);
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else
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br_fdb_unsync_static(p->br, p);
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}
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static void release_nbp(struct kobject *kobj)
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{
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struct net_bridge_port *p
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= container_of(kobj, struct net_bridge_port, kobj);
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kfree(p);
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}
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static void brport_get_ownership(const struct kobject *kobj, kuid_t *uid, kgid_t *gid)
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{
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struct net_bridge_port *p = kobj_to_brport(kobj);
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net_ns_get_ownership(dev_net(p->dev), uid, gid);
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}
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static const struct kobj_type brport_ktype = {
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#ifdef CONFIG_SYSFS
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.sysfs_ops = &brport_sysfs_ops,
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#endif
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.release = release_nbp,
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.get_ownership = brport_get_ownership,
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};
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static void destroy_nbp(struct net_bridge_port *p)
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{
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struct net_device *dev = p->dev;
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p->br = NULL;
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p->dev = NULL;
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netdev_put(dev, &p->dev_tracker);
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kobject_put(&p->kobj);
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}
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static void destroy_nbp_rcu(struct rcu_head *head)
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{
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struct net_bridge_port *p =
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container_of(head, struct net_bridge_port, rcu);
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destroy_nbp(p);
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}
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static unsigned get_max_headroom(struct net_bridge *br)
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{
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unsigned max_headroom = 0;
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struct net_bridge_port *p;
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list_for_each_entry(p, &br->port_list, list) {
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unsigned dev_headroom = netdev_get_fwd_headroom(p->dev);
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if (dev_headroom > max_headroom)
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max_headroom = dev_headroom;
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}
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return max_headroom;
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}
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static void update_headroom(struct net_bridge *br, int new_hr)
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{
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struct net_bridge_port *p;
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list_for_each_entry(p, &br->port_list, list)
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netdev_set_rx_headroom(p->dev, new_hr);
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br->dev->needed_headroom = new_hr;
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}
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/* Delete port(interface) from bridge is done in two steps.
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* via RCU. First step, marks device as down. That deletes
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* all the timers and stops new packets from flowing through.
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*
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* Final cleanup doesn't occur until after all CPU's finished
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* processing packets.
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*
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* Protected from multiple admin operations by RTNL mutex
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*/
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static void del_nbp(struct net_bridge_port *p)
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{
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struct net_bridge *br = p->br;
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struct net_device *dev = p->dev;
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sysfs_remove_link(br->ifobj, p->dev->name);
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nbp_delete_promisc(p);
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spin_lock_bh(&br->lock);
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br_stp_disable_port(p);
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spin_unlock_bh(&br->lock);
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br_mrp_port_del(br, p);
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br_cfm_port_del(br, p);
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br_ifinfo_notify(RTM_DELLINK, NULL, p);
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list_del_rcu(&p->list);
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if (netdev_get_fwd_headroom(dev) == br->dev->needed_headroom)
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update_headroom(br, get_max_headroom(br));
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netdev_reset_rx_headroom(dev);
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nbp_vlan_flush(p);
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br_fdb_delete_by_port(br, p, 0, 1);
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switchdev_deferred_process();
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nbp_backup_clear(p);
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nbp_update_port_count(br);
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netdev_upper_dev_unlink(dev, br->dev);
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dev->priv_flags &= ~IFF_BRIDGE_PORT;
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netdev_rx_handler_unregister(dev);
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br_multicast_del_port(p);
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kobject_uevent(&p->kobj, KOBJ_REMOVE);
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kobject_del(&p->kobj);
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br_netpoll_disable(p);
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call_rcu(&p->rcu, destroy_nbp_rcu);
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}
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/* Delete bridge device */
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void br_dev_delete(struct net_device *dev, struct list_head *head)
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{
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struct net_bridge *br = netdev_priv(dev);
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struct net_bridge_port *p, *n;
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list_for_each_entry_safe(p, n, &br->port_list, list) {
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del_nbp(p);
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}
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br_recalculate_neigh_suppress_enabled(br);
|
|
|
|
br_fdb_delete_by_port(br, NULL, 0, 1);
|
|
|
|
cancel_delayed_work_sync(&br->gc_work);
|
|
|
|
br_sysfs_delbr(br->dev);
|
|
unregister_netdevice_queue(br->dev, head);
|
|
}
|
|
|
|
/* find an available port number */
|
|
static int find_portno(struct net_bridge *br)
|
|
{
|
|
int index;
|
|
struct net_bridge_port *p;
|
|
unsigned long *inuse;
|
|
|
|
inuse = bitmap_zalloc(BR_MAX_PORTS, GFP_KERNEL);
|
|
if (!inuse)
|
|
return -ENOMEM;
|
|
|
|
__set_bit(0, inuse); /* zero is reserved */
|
|
list_for_each_entry(p, &br->port_list, list)
|
|
__set_bit(p->port_no, inuse);
|
|
|
|
index = find_first_zero_bit(inuse, BR_MAX_PORTS);
|
|
bitmap_free(inuse);
|
|
|
|
return (index >= BR_MAX_PORTS) ? -EXFULL : index;
|
|
}
|
|
|
|
/* called with RTNL but without bridge lock */
|
|
static struct net_bridge_port *new_nbp(struct net_bridge *br,
|
|
struct net_device *dev)
|
|
{
|
|
struct net_bridge_port *p;
|
|
int index, err;
|
|
|
|
index = find_portno(br);
|
|
if (index < 0)
|
|
return ERR_PTR(index);
|
|
|
|
p = kzalloc(sizeof(*p), GFP_KERNEL);
|
|
if (p == NULL)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
p->br = br;
|
|
netdev_hold(dev, &p->dev_tracker, GFP_KERNEL);
|
|
p->dev = dev;
|
|
p->path_cost = port_cost(dev);
|
|
p->priority = 0x8000 >> BR_PORT_BITS;
|
|
p->port_no = index;
|
|
p->flags = BR_LEARNING | BR_FLOOD | BR_MCAST_FLOOD | BR_BCAST_FLOOD;
|
|
br_init_port(p);
|
|
br_set_state(p, BR_STATE_DISABLED);
|
|
br_stp_port_timer_init(p);
|
|
err = br_multicast_add_port(p);
|
|
if (err) {
|
|
netdev_put(dev, &p->dev_tracker);
|
|
kfree(p);
|
|
p = ERR_PTR(err);
|
|
}
|
|
|
|
return p;
|
|
}
|
|
|
|
int br_add_bridge(struct net *net, const char *name)
|
|
{
|
|
struct net_device *dev;
|
|
int res;
|
|
|
|
dev = alloc_netdev(sizeof(struct net_bridge), name, NET_NAME_UNKNOWN,
|
|
br_dev_setup);
|
|
|
|
if (!dev)
|
|
return -ENOMEM;
|
|
|
|
dev_net_set(dev, net);
|
|
dev->rtnl_link_ops = &br_link_ops;
|
|
|
|
res = register_netdevice(dev);
|
|
if (res)
|
|
free_netdev(dev);
|
|
return res;
|
|
}
|
|
|
|
int br_del_bridge(struct net *net, const char *name)
|
|
{
|
|
struct net_device *dev;
|
|
int ret = 0;
|
|
|
|
dev = __dev_get_by_name(net, name);
|
|
if (dev == NULL)
|
|
ret = -ENXIO; /* Could not find device */
|
|
|
|
else if (!netif_is_bridge_master(dev)) {
|
|
/* Attempt to delete non bridge device! */
|
|
ret = -EPERM;
|
|
}
|
|
|
|
else if (dev->flags & IFF_UP) {
|
|
/* Not shutdown yet. */
|
|
ret = -EBUSY;
|
|
}
|
|
|
|
else
|
|
br_dev_delete(dev, NULL);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
|
|
static int br_mtu_min(const struct net_bridge *br)
|
|
{
|
|
const struct net_bridge_port *p;
|
|
int ret_mtu = 0;
|
|
|
|
list_for_each_entry(p, &br->port_list, list)
|
|
if (!ret_mtu || ret_mtu > p->dev->mtu)
|
|
ret_mtu = p->dev->mtu;
|
|
|
|
return ret_mtu ? ret_mtu : ETH_DATA_LEN;
|
|
}
|
|
|
|
void br_mtu_auto_adjust(struct net_bridge *br)
|
|
{
|
|
ASSERT_RTNL();
|
|
|
|
/* if the bridge MTU was manually configured don't mess with it */
|
|
if (br_opt_get(br, BROPT_MTU_SET_BY_USER))
|
|
return;
|
|
|
|
/* change to the minimum MTU and clear the flag which was set by
|
|
* the bridge ndo_change_mtu callback
|
|
*/
|
|
dev_set_mtu(br->dev, br_mtu_min(br));
|
|
br_opt_toggle(br, BROPT_MTU_SET_BY_USER, false);
|
|
}
|
|
|
|
static void br_set_gso_limits(struct net_bridge *br)
|
|
{
|
|
unsigned int tso_max_size = TSO_MAX_SIZE;
|
|
const struct net_bridge_port *p;
|
|
u16 tso_max_segs = TSO_MAX_SEGS;
|
|
|
|
list_for_each_entry(p, &br->port_list, list) {
|
|
tso_max_size = min(tso_max_size, p->dev->tso_max_size);
|
|
tso_max_segs = min(tso_max_segs, p->dev->tso_max_segs);
|
|
}
|
|
netif_set_tso_max_size(br->dev, tso_max_size);
|
|
netif_set_tso_max_segs(br->dev, tso_max_segs);
|
|
}
|
|
|
|
/*
|
|
* Recomputes features using slave's features
|
|
*/
|
|
netdev_features_t br_features_recompute(struct net_bridge *br,
|
|
netdev_features_t features)
|
|
{
|
|
struct net_bridge_port *p;
|
|
netdev_features_t mask;
|
|
|
|
if (list_empty(&br->port_list))
|
|
return features;
|
|
|
|
mask = features;
|
|
features &= ~NETIF_F_ONE_FOR_ALL;
|
|
|
|
list_for_each_entry(p, &br->port_list, list) {
|
|
features = netdev_increment_features(features,
|
|
p->dev->features, mask);
|
|
}
|
|
features = netdev_add_tso_features(features, mask);
|
|
|
|
return features;
|
|
}
|
|
|
|
/* called with RTNL */
|
|
int br_add_if(struct net_bridge *br, struct net_device *dev,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
struct net_bridge_port *p;
|
|
int err = 0;
|
|
unsigned br_hr, dev_hr;
|
|
bool changed_addr, fdb_synced = false;
|
|
|
|
/* Don't allow bridging non-ethernet like devices. */
|
|
if ((dev->flags & IFF_LOOPBACK) ||
|
|
dev->type != ARPHRD_ETHER || dev->addr_len != ETH_ALEN ||
|
|
!is_valid_ether_addr(dev->dev_addr))
|
|
return -EINVAL;
|
|
|
|
/* No bridging of bridges */
|
|
if (dev->netdev_ops->ndo_start_xmit == br_dev_xmit) {
|
|
NL_SET_ERR_MSG(extack,
|
|
"Can not enslave a bridge to a bridge");
|
|
return -ELOOP;
|
|
}
|
|
|
|
/* Device has master upper dev */
|
|
if (netdev_master_upper_dev_get(dev))
|
|
return -EBUSY;
|
|
|
|
/* No bridging devices that dislike that (e.g. wireless) */
|
|
if (dev->priv_flags & IFF_DONT_BRIDGE) {
|
|
NL_SET_ERR_MSG(extack,
|
|
"Device does not allow enslaving to a bridge");
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
p = new_nbp(br, dev);
|
|
if (IS_ERR(p))
|
|
return PTR_ERR(p);
|
|
|
|
call_netdevice_notifiers(NETDEV_JOIN, dev);
|
|
|
|
err = dev_set_allmulti(dev, 1);
|
|
if (err) {
|
|
br_multicast_del_port(p);
|
|
netdev_put(dev, &p->dev_tracker);
|
|
kfree(p); /* kobject not yet init'd, manually free */
|
|
goto err1;
|
|
}
|
|
|
|
err = kobject_init_and_add(&p->kobj, &brport_ktype, &(dev->dev.kobj),
|
|
SYSFS_BRIDGE_PORT_ATTR);
|
|
if (err)
|
|
goto err2;
|
|
|
|
err = br_sysfs_addif(p);
|
|
if (err)
|
|
goto err2;
|
|
|
|
err = br_netpoll_enable(p);
|
|
if (err)
|
|
goto err3;
|
|
|
|
err = netdev_rx_handler_register(dev, br_get_rx_handler(dev), p);
|
|
if (err)
|
|
goto err4;
|
|
|
|
dev->priv_flags |= IFF_BRIDGE_PORT;
|
|
|
|
err = netdev_master_upper_dev_link(dev, br->dev, NULL, NULL, extack);
|
|
if (err)
|
|
goto err5;
|
|
|
|
dev_disable_lro(dev);
|
|
|
|
list_add_rcu(&p->list, &br->port_list);
|
|
|
|
nbp_update_port_count(br);
|
|
if (!br_promisc_port(p) && (p->dev->priv_flags & IFF_UNICAST_FLT)) {
|
|
/* When updating the port count we also update all ports'
|
|
* promiscuous mode.
|
|
* A port leaving promiscuous mode normally gets the bridge's
|
|
* fdb synced to the unicast filter (if supported), however,
|
|
* `br_port_clear_promisc` does not distinguish between
|
|
* non-promiscuous ports and *new* ports, so we need to
|
|
* sync explicitly here.
|
|
*/
|
|
fdb_synced = br_fdb_sync_static(br, p) == 0;
|
|
if (!fdb_synced)
|
|
netdev_err(dev, "failed to sync bridge static fdb addresses to this port\n");
|
|
}
|
|
|
|
netdev_update_features(br->dev);
|
|
|
|
br_hr = br->dev->needed_headroom;
|
|
dev_hr = netdev_get_fwd_headroom(dev);
|
|
if (br_hr < dev_hr)
|
|
update_headroom(br, dev_hr);
|
|
else
|
|
netdev_set_rx_headroom(dev, br_hr);
|
|
|
|
if (br_fdb_add_local(br, p, dev->dev_addr, 0))
|
|
netdev_err(dev, "failed insert local address bridge forwarding table\n");
|
|
|
|
if (br->dev->addr_assign_type != NET_ADDR_SET) {
|
|
/* Ask for permission to use this MAC address now, even if we
|
|
* don't end up choosing it below.
|
|
*/
|
|
err = dev_pre_changeaddr_notify(br->dev, dev->dev_addr, extack);
|
|
if (err)
|
|
goto err6;
|
|
}
|
|
|
|
err = nbp_vlan_init(p, extack);
|
|
if (err) {
|
|
netdev_err(dev, "failed to initialize vlan filtering on this port\n");
|
|
goto err6;
|
|
}
|
|
|
|
spin_lock_bh(&br->lock);
|
|
changed_addr = br_stp_recalculate_bridge_id(br);
|
|
|
|
if (netif_running(dev) && netif_oper_up(dev) &&
|
|
(br->dev->flags & IFF_UP))
|
|
br_stp_enable_port(p);
|
|
spin_unlock_bh(&br->lock);
|
|
|
|
br_ifinfo_notify(RTM_NEWLINK, NULL, p);
|
|
|
|
if (changed_addr)
|
|
call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
|
|
|
|
br_mtu_auto_adjust(br);
|
|
br_set_gso_limits(br);
|
|
|
|
kobject_uevent(&p->kobj, KOBJ_ADD);
|
|
|
|
return 0;
|
|
|
|
err6:
|
|
if (fdb_synced)
|
|
br_fdb_unsync_static(br, p);
|
|
list_del_rcu(&p->list);
|
|
br_fdb_delete_by_port(br, p, 0, 1);
|
|
nbp_update_port_count(br);
|
|
netdev_upper_dev_unlink(dev, br->dev);
|
|
err5:
|
|
dev->priv_flags &= ~IFF_BRIDGE_PORT;
|
|
netdev_rx_handler_unregister(dev);
|
|
err4:
|
|
br_netpoll_disable(p);
|
|
err3:
|
|
sysfs_remove_link(br->ifobj, p->dev->name);
|
|
err2:
|
|
br_multicast_del_port(p);
|
|
netdev_put(dev, &p->dev_tracker);
|
|
kobject_put(&p->kobj);
|
|
dev_set_allmulti(dev, -1);
|
|
err1:
|
|
return err;
|
|
}
|
|
|
|
/* called with RTNL */
|
|
int br_del_if(struct net_bridge *br, struct net_device *dev)
|
|
{
|
|
struct net_bridge_port *p;
|
|
bool changed_addr;
|
|
|
|
p = br_port_get_rtnl(dev);
|
|
if (!p || p->br != br)
|
|
return -EINVAL;
|
|
|
|
/* Since more than one interface can be attached to a bridge,
|
|
* there still maybe an alternate path for netconsole to use;
|
|
* therefore there is no reason for a NETDEV_RELEASE event.
|
|
*/
|
|
del_nbp(p);
|
|
|
|
br_mtu_auto_adjust(br);
|
|
br_set_gso_limits(br);
|
|
|
|
spin_lock_bh(&br->lock);
|
|
changed_addr = br_stp_recalculate_bridge_id(br);
|
|
spin_unlock_bh(&br->lock);
|
|
|
|
if (changed_addr)
|
|
call_netdevice_notifiers(NETDEV_CHANGEADDR, br->dev);
|
|
|
|
netdev_update_features(br->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void br_port_flags_change(struct net_bridge_port *p, unsigned long mask)
|
|
{
|
|
struct net_bridge *br = p->br;
|
|
|
|
if (mask & BR_AUTO_MASK)
|
|
nbp_update_port_count(br);
|
|
|
|
if (mask & (BR_NEIGH_SUPPRESS | BR_NEIGH_VLAN_SUPPRESS))
|
|
br_recalculate_neigh_suppress_enabled(br);
|
|
}
|
|
|
|
bool br_port_flag_is_set(const struct net_device *dev, unsigned long flag)
|
|
{
|
|
struct net_bridge_port *p;
|
|
|
|
p = br_port_get_rtnl_rcu(dev);
|
|
if (!p)
|
|
return false;
|
|
|
|
return p->flags & flag;
|
|
}
|
|
EXPORT_SYMBOL_GPL(br_port_flag_is_set);
|