BMC/Intel-BMC/linux.git/net/bridge/br_device.c, branch dev-4.3

bridge: fix lockdep addr_list_lock false positive splat

2016-01-31T19:25:51+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

net: bridge: convert to using IFF_NO_QUEUE

2015-08-18T18:55:06+00:00

Signed-off-by: Phil Sutter Cc: Stephen Hemminger Signed-off-by: David S. Miller

bridge: Don't segment multiple tagged packets on bridge device

2015-08-03T21:24:50+00:00

Bridge devices don't need to segment multiple tagged packets since thier ports can segment them. Signed-off-by: Toshiaki Makita Signed-off-by: David S. Miller

netfilter: bridge: use rcu hook to resolve br_netfilter dependency

2015-03-10T14:03:02+00:00

e5de75b ("netfilter: bridge: move DNAT helper to br_netfilter") results in the following link problem: net/bridge/br_device.c:29: undefined reference to `br_nf_prerouting_finish_bridge` Moreover it creates a hard dependency between br_netfilter and the bridge core, which is what we've been trying to avoid so far. Resolve this problem by using a hook structure so we reduce #ifdef pollution and keep bridge netfilter specific code under br_netfilter.c which was the original intention. Reported-by: Simon Horman Signed-off-by: Pablo Neira Ayuso

netfilter: bridge: move DNAT helper to br_netfilter

2015-03-09T16:56:07+00:00

Only one caller, there is no need to keep this in a header. Move it to br_netfilter.c where this belongs to. Based on patch from Florian Westphal. Signed-off-by: Pablo Neira Ayuso

bridge: Add filtering support for default_pvid

2014-10-06T01:21:37+00:00

Currently when vlan filtering is turned on on the bridge, the bridge will drop all traffic untill the user configures the filter. This isn't very nice for ports that don't care about vlans and just want untagged traffic. A concept of a default_pvid was recently introduced. This patch adds filtering support for default_pvid. Now, ports that don't care about vlans and don't define there own filter will belong to the VLAN of the default_pvid and continue to receive untagged traffic. This filtering can be disabled by setting default_pvid to 0. Signed-off-by: Vladislav Yasevich Signed-off-by: David S. Miller

netfilter: bridge: move br_netfilter out of the core

2014-09-26T16:42:31+00:00

Jesper reported that br_netfilter always registers the hooks since this is part of the bridge core. This harms performance for people that don't need this. This patch modularizes br_netfilter so it can be rmmod'ed, thus, the hooks can be unregistered. I think the bridge netfilter should have been a separated module since the beginning, Patrick agreed on that. Note that this is breaking compatibility for users that expect that bridge netfilter is going to be available after explicitly 'modprobe bridge' or via automatic load through brctl. However, the damage can be easily undone by modprobing br_netfilter. The bridge core also spots a message to provide a clue to people that didn't notice that this has been deprecated. On top of that, the plan is that nftables will not rely on this software layer, but integrate the connection tracking into the bridge layer to enable stateful filtering and NAT, which is was bridge netfilter users seem to require. This patch still keeps the fake_dst_ops in the bridge core, since this is required by when the bridge port is initialized. So we can safely modprobe/rmmod br_netfilter anytime. Signed-off-by: Pablo Neira Ayuso Acked-by: Florian Westphal

bridge: Prepare for forwarding another bridge group addresses

2014-06-11T22:22:53+00:00

If a bridge is an 802.1ad bridge, it must forward another bridge group addresses (the Nearest Customer Bridge group addresses). (For details, see IEEE 802.1Q-2011 8.6.3.) As user might not want group_fwd_mask to be modified by enabling 802.1ad, introduce a new mask, group_fwd_mask_required, which indicates addresses the bridge wants to forward. This will be set by enabling 802.1ad. Signed-off-by: Toshiaki Makita Signed-off-by: David S. Miller

bridge: Prepare for 802.1ad vlan filtering support

2014-06-11T22:22:53+00:00

This enables a bridge to have vlan protocol informantion and allows vlan tag manipulation (retrieve, insert and remove tags) according to the vlan protocol. Signed-off-by: Toshiaki Makita Signed-off-by: David S. Miller

bridge: Add 802.1ad tx vlan acceleration

2014-06-11T22:22:53+00:00

Bridge device doesn't need to embed S-tag into skb->data. Signed-off-by: Toshiaki Makita Signed-off-by: David S. Miller