linux-toradex.git/net/bridge/br_device.c, branch v4.9.65

bridge: switchdev: Clear forward mark when transmitting packet

2017-09-20T06:19:55+00:00

[ Upstream commit 79e99bdd60b484af9afe0147e85a13e66d5c1cdb ]

Commit 6bc506b4fb06 ("bridge: switchdev: Add forward mark support for
stacked devices") added the 'offload_fwd_mark' bit to the skb in order
to allow drivers to indicate to the bridge driver that they already
forwarded the packet in L2.

In case the bit is set, before transmitting the packet from each port,
the port's mark is compared with the mark stored in the skb's control
block. If both marks are equal, we know the packet arrived from a switch
device that already forwarded the packet and it's not re-transmitted.

However, if the packet is transmitted from the bridge device itself
(e.g., br0), we should clear the 'offload_fwd_mark' bit as the mark
stored in the skb's control block isn't valid.

This scenario can happen in rare cases where a packet was trapped during
L3 forwarding and forwarded by the kernel to a bridge device.

Fixes: 6bc506b4fb06 ("bridge: switchdev: Add forward mark support for stacked devices")
Signed-off-by: Ido Schimmel 
Reported-by: Yotam Gigi 
Tested-by: Yotam Gigi 
Reviewed-by: Jiri Pirko 
Acked-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net: bridge: change unicast boolean to exact pkt_type

2016-09-02T05:48:33+00:00

Remove the unicast flag and introduce an exact pkt_type. That would help us
for the upcoming per-port multicast flood flag and also slightly reduce the
tests in the input fast path.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

net: bridge: remove _deliver functions and consolidate forward code

2016-07-17T02:57:38+00:00

Before this patch we had two flavors of most forwarding functions -
_forward and _deliver, the difference being that the latter are used
when the packets are locally originated. Instead of all this function
pointer passing and code duplication, we can just pass a boolean noting
that the packet was locally originated and use that to perform the
necessary checks in __br_forward. This gives a minor performance
improvement but more importantly consolidates the forwarding paths.
Also add a kernel doc comment to explain the exported br_forward()'s
arguments.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

net: introduce default neigh_construct/destroy ndo calls for L2 upper devices

2016-07-05T16:06:28+00:00

L2 upper device needs to propagate neigh_construct/destroy calls down to
lower devices. Do this by defining default ndo functions and use them in
team, bond, bridge and vlan.

Signed-off-by: Jiri Pirko 
Reviewed-by: Ido Schimmel 
Signed-off-by: David S. Miller

net: bridge: add support for IGMP/MLD stats and export them via netlink

2016-06-30T10:18:24+00:00

This patch adds stats support for the currently used IGMP/MLD types by the
bridge. The stats are per-port (plus one stat per-bridge) and per-direction
(RX/TX). The stats are exported via netlink via the new linkxstats API
(RTM_GETSTATS). In order to minimize the performance impact, a new option
is used to enable/disable the stats - multicast_stats_enabled, similar to
the recent vlan stats. Also in order to avoid multiple IGMP/MLD type
lookups and checks, we make use of the current "igmp" member of the bridge
private skb->cb region to record the type on Rx (both host-generated and
external packets pass by multicast_rcv()). We can do that since the igmp
member was used as a boolean and all the valid IGMP/MLD types are positive
values. The normal bridge fast-path is not affected at all, the only
affected paths are the flooding ones and since we make use of the IGMP/MLD
type, we can quickly determine if the packet should be counted using
cache-hot data (cb's igmp member). We add counters for:
* IGMP Queries
* IGMP Leaves
* IGMP v1/v2/v3 reports

* MLD Queries
* MLD Leaves
* MLD v1/v2 reports

These are invaluable when monitoring or debugging complex multicast setups
with bridges.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bridge: fix lockdep addr_list_lock false positive splat

2016-01-15T20:40:45+00:00

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

bridge: vlan: use proper rcu for the vlgrp member

2015-10-13T11:57:52+00:00

The bridge and port's vlgrp member is already used in RCU way, currently
we rely on the fact that it cannot disappear while the port exists but
that is error-prone and we might miss places with improper locking
(either RCU or RTNL must be held to walk the vlan_list). So make it
official and use RCU for vlgrp to catch offenders. Introduce proper vlgrp
accessors and use them consistently throughout the code.

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

bridge: vlan: move pvid inside net_bridge_vlan_group

2015-10-02T01:24:04+00:00

One obvious way to converge more code (which was also used by the
previous vlan code) is to move pvid inside net_bridge_vlan_group. This
allows us to simplify some and remove other port-specific functions.
Also gives us the ability to simply pass the vlan group and use all of the
contained information.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bridge: vlan: add per-vlan struct and move to rhashtables

2015-09-29T20:36:06+00:00

This patch changes the bridge vlan implementation to use rhashtables
instead of bitmaps. The main motivation behind this change is that we
need extensible per-vlan structures (both per-port and global) so more
advanced features can be introduced and the vlan support can be
extended. I've tried to break this up but the moment net_port_vlans is
changed and the whole API goes away, thus this is a larger patch.
A few short goals of this patch are:
- Extensible per-vlan structs stored in rhashtables and a sorted list
- Keep user-visible behaviour (compressed vlans etc)
- Keep fastpath ingress/egress logic the same (optimizations to come
  later)

Here's a brief list of some of the new features we'd like to introduce:
- per-vlan counters
- vlan ingress/egress mapping
- per-vlan igmp configuration
- vlan priorities
- avoid fdb entries replication (e.g. local fdb scaling issues)

The structure is kept single for both global and per-port entries so to
avoid code duplication where possible and also because we'll soon introduce
"port0 / aka bridge as port" which should simplify things further
(thanks to Vlad for the suggestion!).

Now we have per-vlan global rhashtable (bridge-wide) and per-vlan port
rhashtable, if an entry is added to a port it'll get a pointer to its
global context so it can be quickly accessed later. There's also a
sorted vlan list which is used for stable walks and some user-visible
behaviour such as the vlan ranges, also for error paths.
VLANs are stored in a "vlan group" which currently contains the
rhashtable, sorted vlan list and the number of "real" vlan entries.
A good side-effect of this change is that it resembles how hw keeps
per-vlan data.
One important note after this change is that if a VLAN is being looked up
in the bridge's rhashtable for filtering purposes (or to check if it's an
existing usable entry, not just a global context) then the new helper
br_vlan_should_use() needs to be used if the vlan is found. In case the
lookup is done only with a port's vlan group, then this check can be
skipped.

Things tested so far:
- basic vlan ingress/egress
- pvids
- untagged vlans
- undef CONFIG_BRIDGE_VLAN_FILTERING
- adding/deleting vlans in different scenarios (with/without global ctx,
  while transmitting traffic, in ranges etc)
- loading/removing the module while having/adding/deleting vlans
- extracting bridge vlan information (user ABI), compressed requests
- adding/deleting fdbs on vlans
- bridge mac change, promisc mode
- default pvid change
- kmemleak ON during the whole time

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bridge: define some min/max/default ageing time constants

2015-09-23T21:35:58+00:00

Signed-off-by: Scott Feldman 
Acked-by: Jiri Pirko 
Signed-off-by: David S. Miller