linux-stable.git/net/bridge, branch v4.4.8

bridge: Allow set bridge ageing time when switchdev disabled

2016-04-20T06:42:05+00:00

[ Upstream commit 5e263f712691615fb802f06c98d7638c378f5d11 ]

When NET_SWITCHDEV=n, switchdev_port_attr_set will return -EOPNOTSUPP,
we should ignore this error code and continue to set the ageing time.

Fixes: c62987bbd8a1 ("bridge: push bridge setting ageing_time down to switchdev")
Signed-off-by: Haishuang Yan 
Acked-by: Ido Schimmel 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: allow zero ageing time

2016-04-20T06:42:02+00:00

[ Upstream commit 4c656c13b254d598e83e586b7b4d36a2043dad85 ]

This fixes a regression in the bridge ageing time caused by:
commit c62987bbd8a1 ("bridge: push bridge setting ageing_time down to switchdev")

There are users of Linux bridge which use the feature that if ageing time
is set to 0 it causes entries to never expire. See:
  https://www.linuxfoundation.org/collaborate/workgroups/networking/bridge

For a pure software bridge, it is unnecessary for the code to have
arbitrary restrictions on what values are allowable.

Signed-off-by: Stephen Hemminger 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

switchdev: Require RTNL mutex to be held when sending FDB notifications

2016-03-03T23:07:04+00:00

[ Upstream commit 4f2c6ae5c64c353fb1b0425e4747e5603feadba1 ]

When switchdev drivers process FDB notifications from the underlying
device they resolve the netdev to which the entry points to and notify
the bridge using the switchdev notifier.

However, since the RTNL mutex is not held there is nothing preventing
the netdev from disappearing in the middle, which will cause
br_switchdev_event() to dereference a non-existing netdev.

Make switchdev drivers hold the lock at the beginning of the
notification processing session and release it once it ends, after
notifying the bridge.

Also, remove switchdev_mutex and fdb_lock, as they are no longer needed
when RTNL mutex is held.

Fixes: 03bf0c281234 ("switchdev: introduce switchdev notifier")
Signed-off-by: Ido Schimmel 
Signed-off-by: Jiri Pirko 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: fix lockdep addr_list_lock false positive splat

2016-01-31T19:29:01+00:00

[ Upstream commit c6894dec8ea9ae05747124dce98b3b5c2e69b168 ]

After promisc mode management was introduced a bridge device could do
dev_set_promiscuity from its ndo_change_rx_flags() callback which in
turn can be called after the bridge's addr_list_lock has been taken
(e.g. by dev_uc_add). This causes a false positive lockdep splat because
the port interfaces' addr_list_lock is taken when br_manage_promisc()
runs after the bridge's addr list lock was already taken.
To remove the false positive introduce a custom bridge addr_list_lock
class and set it on bridge init.
A simple way to reproduce this is with the following:
$ brctl addbr br0
$ ip l add l br0 br0.100 type vlan id 100
$ ip l set br0 up
$ ip l set br0.100 up
$ echo 1 > /sys/class/net/br0/bridge/vlan_filtering
$ brctl addif br0 eth0
Splat:
[   43.684325] =============================================
[   43.684485] [ INFO: possible recursive locking detected ]
[   43.684636] 4.4.0-rc8+ #54 Not tainted
[   43.684755] ---------------------------------------------
[   43.684906] brctl/1187 is trying to acquire lock:
[   43.685047]  (_xmit_ETHER){+.....}, at: [] dev_set_rx_mode+0x1e/0x40
[   43.685460]  but task is already holding lock:
[   43.685618]  (_xmit_ETHER){+.....}, at: [] dev_uc_add+0x27/0x80
[   43.686015]  other info that might help us debug this:
[   43.686316]  Possible unsafe locking scenario:

[   43.686743]        CPU0
[   43.686967]        ----
[   43.687197]   lock(_xmit_ETHER);
[   43.687544]   lock(_xmit_ETHER);
[   43.687886] *** DEADLOCK ***

[   43.688438]  May be due to missing lock nesting notation

[   43.688882] 2 locks held by brctl/1187:
[   43.689134]  #0:  (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20
[   43.689852]  #1:  (_xmit_ETHER){+.....}, at: [] dev_uc_add+0x27/0x80
[   43.690575] stack backtrace:
[   43.690970] CPU: 0 PID: 1187 Comm: brctl Not tainted 4.4.0-rc8+ #54
[   43.691270] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.8.1-20150318_183358- 04/01/2014
[   43.691770]  ffffffff826a25c0 ffff8800369fb8e0 ffffffff81360ceb ffffffff826a25c0
[   43.692425]  ffff8800369fb9b8 ffffffff810d0466 ffff8800369fb968 ffffffff81537139
[   43.693071]  ffff88003a08c880 0000000000000000 00000000ffffffff 0000000002080020
[   43.693709] Call Trace:
[   43.693931]  [] dump_stack+0x4b/0x70
[   43.694199]  [] __lock_acquire+0x1e46/0x1e90
[   43.694483]  [] ? netlink_broadcast_filtered+0x139/0x3e0
[   43.694789]  [] ? nlmsg_notify+0x5a/0xc0
[   43.695064]  [] lock_acquire+0xe5/0x1f0
[   43.695340]  [] ? dev_set_rx_mode+0x1e/0x40
[   43.695623]  [] _raw_spin_lock_bh+0x45/0x80
[   43.695901]  [] ? dev_set_rx_mode+0x1e/0x40
[   43.696180]  [] dev_set_rx_mode+0x1e/0x40
[   43.696460]  [] dev_set_promiscuity+0x3c/0x50
[   43.696750]  [] br_port_set_promisc+0x25/0x50 [bridge]
[   43.697052]  [] br_manage_promisc+0x8a/0xe0 [bridge]
[   43.697348]  [] br_dev_change_rx_flags+0x1e/0x20 [bridge]
[   43.697655]  [] __dev_set_promiscuity+0x132/0x1f0
[   43.697943]  [] __dev_set_rx_mode+0x82/0x90
[   43.698223]  [] dev_uc_add+0x5e/0x80
[   43.698498]  [] vlan_device_event+0x542/0x650 [8021q]
[   43.698798]  [] notifier_call_chain+0x5d/0x80
[   43.699083]  [] raw_notifier_call_chain+0x16/0x20
[   43.699374]  [] call_netdevice_notifiers_info+0x6e/0x80
[   43.699678]  [] call_netdevice_notifiers+0x16/0x20
[   43.699973]  [] br_add_if+0x47e/0x4c0 [bridge]
[   43.700259]  [] add_del_if+0x6e/0x80 [bridge]
[   43.700548]  [] br_dev_ioctl+0xaf/0xc0 [bridge]
[   43.700836]  [] dev_ifsioc+0x30c/0x3c0
[   43.701106]  [] dev_ioctl+0xf9/0x6f0
[   43.701379]  [] ? mntput_no_expire+0x5/0x450
[   43.701665]  [] ? mntput_no_expire+0xae/0x450
[   43.701947]  [] sock_do_ioctl+0x42/0x50
[   43.702219]  [] sock_ioctl+0x1e5/0x290
[   43.702500]  [] do_vfs_ioctl+0x2cb/0x5c0
[   43.702771]  [] SyS_ioctl+0x79/0x90
[   43.703033]  [] entry_SYSCALL_64_fastpath+0x16/0x7a

CC: Vlad Yasevich 
CC: Stephen Hemminger 
CC: Bridge list 
CC: Andy Gospodarek 
CC: Roopa Prabhu 
Fixes: 2796d0c648c9 ("bridge: Automatically manage port promiscuous mode.")
Reported-by: Andy Gospodarek 
Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

bridge: Only call /sbin/bridge-stp for the initial network namespace

2016-01-05T21:46:17+00:00

[I stole this patch from Eric Biederman. He wrote:]

> There is no defined mechanism to pass network namespace information
> into /sbin/bridge-stp therefore don't even try to invoke it except
> for bridge devices in the initial network namespace.
>
> It is possible for unprivileged users to cause /sbin/bridge-stp to be
> invoked for any network device name which if /sbin/bridge-stp does not
> guard against unreasonable arguments or being invoked twice on the
> same network device could cause problems.

[Hannes: changed patch using netns_eq]

Cc: Eric W. Biederman 
Signed-off-by: Eric W. Biederman 
Signed-off-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

switchdev: bridge: Pass ageing time as clock_t instead of jiffies

2015-12-22T20:56:44+00:00

The bridge's ageing time is offloaded to hardware when:
	1) A port joins a bridge
	2) The ageing time of the bridge is changed

In the first case the ageing time is offloaded as jiffies, but in the
second case it's offloaded as clock_t, which is what existing switchdev
drivers expect to receive.

Fixes: 6ac311ae8bfb ("Adding switchdev ageing notification on port bridged")
Signed-off-by: Ido Schimmel 
Signed-off-by: Jiri Pirko 
Signed-off-by: David S. Miller

switchdev: bridge: Check return code is not EOPNOTSUPP

2015-11-16T19:56:03+00:00

When NET_SWITCHDEV=n, switchdev_port_attr_set simply returns EOPNOTSUPP.
In this case we should not emit errors and warnings to the kernel log.

Reported-by: Sander Eikelenboom 
Tested-by: Christian Borntraeger 
Fixes: 0bc05d585d38 ("switchdev: allow caller to explicitly request
attr_set as deferred")
Fixes: 6ac311ae8bfb ("Adding switchdev ageing notification on port
bridged")
Signed-off-by: Ido Schimmel 
Signed-off-by: Jiri Pirko 
Signed-off-by: David S. Miller

Revert "bridge: Allow forward delay to be cfgd when STP enabled"

2015-11-10T20:41:36+00:00

This reverts commit 34c2d9fb0498c066afbe610b15e18995fd8be792.

There are 2 reasons for this revert:
 1)  The commit in question doesn't do what it says it does.  The
     description reads: "Allow bridge forward delay to be configured
     when Spanning Tree is enabled."  This was already the case before
     the commit was made.  What the commit actually do was disallow
     invalid values or 'forward_delay' when STP was turned off.

 2)  The above change was actually a change in the user observed
     behavior and broke things like libvirt and other network configs
     that set 'forward_delay' to 0 without enabling STP.  The value
     of 0 is actually used when STP is turned off to immediately mark
     the bridge as forwarding.

Signed-off-by: Vlad Yasevich 
Signed-off-by: David S. Miller

bridge: vlan: Use rcu_dereference instead of rtnl_dereference

2015-11-02T21:27:39+00:00

br_should_learn() is protected by RCU and not by RTNL, so use correct
flavor of nbp_vlan_group().

Fixes: 907b1e6e83ed ("bridge: vlan: use proper rcu for the vlgrp
member")
Signed-off-by: Ido Schimmel 
Acked-by: Nikolay Aleksandrov 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller

bridge: vlan: Use correct flag name in comment

2015-11-02T20:40:11+00:00

The flag used to indicate if a VLAN should be used for filtering - as
opposed to context only - on the bridge itself (e.g. br0) is called
'brentry' and not 'brvlan'.

Signed-off-by: Ido Schimmel 
Acked-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller