Taehee Yoo e1f469cd58 Revert "netns: don't disable BHs when locking "nsid_lock"" ... This reverts commit 8d7e5dee97. To protect netns id, the nsid_lock is used when netns id is being allocated and removed by peernet2id_alloc() and unhash_nsid(). The nsid_lock can be used in BH context but only spin_lock() is used in this code. Using spin_lock() instead of spin_lock_bh() can result in a deadlock in the following scenario reported by the lockdep. In order to avoid a deadlock, the spin_lock_bh() should be used instead of spin_lock() to acquire nsid_lock. Test commands: ip netns del nst ip netns add nst ip link add veth1 type veth peer name veth2 ip link set veth1 netns nst ip netns exec nst ip link add name br1 type bridge vlan_filtering 1 ip netns exec nst ip link set dev br1 up ip netns exec nst ip link set dev veth1 master br1 ip netns exec nst ip link set dev veth1 up ip netns exec nst ip link add macvlan0 link br1 up type macvlan Splat looks like: [ 33.615860][ T607] WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected [ 33.617194][ T607] 5.9.0-rc1+ #665 Not tainted [ ... ] [ 33.670615][ T607] Chain exists of: [ 33.670615][ T607] &mc->mca_lock --> &bridge_netdev_addr_lock_key --> &net->nsid_lock [ 33.670615][ T607] [ 33.673118][ T607] Possible interrupt unsafe locking scenario: [ 33.673118][ T607] [ 33.674599][ T607] CPU0 CPU1 [ 33.675557][ T607] ---- ---- [ 33.676516][ T607] lock(&net->nsid_lock); [ 33.677306][ T607] local_irq_disable(); [ 33.678517][ T607] lock(&mc->mca_lock); [ 33.679725][ T607] lock(&bridge_netdev_addr_lock_key); [ 33.681166][ T607] <Interrupt> [ 33.681791][ T607] lock(&mc->mca_lock); [ 33.682579][ T607] [ 33.682579][ T607] *** DEADLOCK *** [ ... ] [ 33.922046][ T607] stack backtrace: [ 33.922999][ T607] CPU: 3 PID: 607 Comm: ip Not tainted 5.9.0-rc1+ #665 [ 33.924099][ T607] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014 [ 33.925714][ T607] Call Trace: [ 33.926238][ T607] dump_stack+0x78/0xab [ 33.926905][ T607] check_irq_usage+0x70b/0x720 [ 33.927708][ T607] ? iterate_chain_key+0x60/0x60 [ 33.928507][ T607] ? check_path+0x22/0x40 [ 33.929201][ T607] ? check_noncircular+0xcf/0x180 [ 33.930024][ T607] ? __lock_acquire+0x1952/0x1f20 [ 33.930860][ T607] __lock_acquire+0x1952/0x1f20 [ 33.931667][ T607] lock_acquire+0xaf/0x3a0 [ 33.932366][ T607] ? peernet2id_alloc+0x3a/0x170 [ 33.933147][ T607] ? br_port_fill_attrs+0x54c/0x6b0 [bridge] [ 33.934140][ T607] ? br_port_fill_attrs+0x5de/0x6b0 [bridge] [ 33.935113][ T607] ? kvm_sched_clock_read+0x14/0x30 [ 33.935974][ T607] _raw_spin_lock+0x30/0x70 [ 33.936728][ T607] ? peernet2id_alloc+0x3a/0x170 [ 33.937523][ T607] peernet2id_alloc+0x3a/0x170 [ 33.938313][ T607] rtnl_fill_ifinfo+0xb5e/0x1400 [ 33.939091][ T607] rtmsg_ifinfo_build_skb+0x8a/0xf0 [ 33.939953][ T607] rtmsg_ifinfo_event.part.39+0x17/0x50 [ 33.940863][ T607] rtmsg_ifinfo+0x1f/0x30 [ 33.941571][ T607] __dev_notify_flags+0xa5/0xf0 [ 33.942376][ T607] ? __irq_work_queue_local+0x49/0x50 [ 33.943249][ T607] ? irq_work_queue+0x1d/0x30 [ 33.943993][ T607] ? __dev_set_promiscuity+0x7b/0x1a0 [ 33.944878][ T607] __dev_set_promiscuity+0x7b/0x1a0 [ 33.945758][ T607] dev_set_promiscuity+0x1e/0x50 [ 33.946582][ T607] br_port_set_promisc+0x1f/0x40 [bridge] [ 33.947487][ T607] br_manage_promisc+0x8b/0xe0 [bridge] [ 33.948388][ T607] __dev_set_promiscuity+0x123/0x1a0 [ 33.949244][ T607] __dev_set_rx_mode+0x68/0x90 [ 33.950021][ T607] dev_uc_add+0x50/0x60 [ 33.950720][ T607] macvlan_open+0x18e/0x1f0 [macvlan] [ 33.951601][ T607] __dev_open+0xd6/0x170 [ 33.952269][ T607] __dev_change_flags+0x181/0x1d0 [ 33.953056][ T607] rtnl_configure_link+0x2f/0xa0 [ 33.953884][ T607] __rtnl_newlink+0x6b9/0x8e0 [ 33.954665][ T607] ? __lock_acquire+0x95d/0x1f20 [ 33.955450][ T607] ? lock_acquire+0xaf/0x3a0 [ 33.956193][ T607] ? is_bpf_text_address+0x5/0xe0 [ 33.956999][ T607] rtnl_newlink+0x47/0x70 Acked-by: Guillaume Nault <gnault@redhat.com> Fixes: 8d7e5dee97 ("netns: don't disable BHs when locking "nsid_lock"") Reported-by: syzbot+3f960c64a104eaa2c813@syzkaller.appspotmail.com Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>		2020-09-07 14:32:39 -07:00
..
bpf_sk_storage.c	bpf: Change uapi for bpf iterator map elements	2020-08-06 16:39:14 -07:00
datagram.c
datagram.h
dev_addr_lists.c
dev_ioctl.c	treewide: Use fallthrough pseudo-keyword	2020-08-23 17:36:59 -05:00
dev.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2020-09-03 18:50:48 -07:00
devlink.c	treewide: Use fallthrough pseudo-keyword	2020-08-23 17:36:59 -05:00
drop_monitor.c	treewide: Use fallthrough pseudo-keyword	2020-08-23 17:36:59 -05:00
dst_cache.c
dst.c
failover.c
fib_notifier.c
fib_rules.c	fib: Fix undef compile warning	2020-08-03 18:01:49 -07:00
filter.c	treewide: Use fallthrough pseudo-keyword	2020-08-23 17:36:59 -05:00
flow_dissector.c
flow_offload.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2020-07-25 17:49:04 -07:00
gen_estimator.c
gen_stats.c
gro_cells.c
hwbm.c
link_watch.c
lwt_bpf.c
lwtunnel.c
Makefile
neighbour.c
net_namespace.c	Revert "netns: don't disable BHs when locking "nsid_lock""	2020-09-07 14:32:39 -07:00
net-procfs.c
net-sysfs.c	net: accept an empty mask in /sys/class/net/*/queues/rx-*/rps_cpus	2020-08-12 13:18:16 -07:00
net-sysfs.h
net-traces.c
netclassid_cgroup.c
netevent.c
netpoll.c	net: disable netpoll on fresh napis	2020-08-26 16:16:39 -07:00
netprio_cgroup.c
page_pool.c
pktgen.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2020-09-03 18:50:48 -07:00
ptp_classifier.c
request_sock.c
rtnetlink.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next	2020-08-03 18:27:40 -07:00
scm.c
secure_seq.c
skbuff.c	net: Get rid of consume_skb when tracing is off	2020-08-24 16:12:26 -07:00
skmsg.c	treewide: Use fallthrough pseudo-keyword	2020-08-23 17:36:59 -05:00
sock_diag.c
sock_map.c
sock_reuseport.c
sock.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net	2020-09-03 18:50:48 -07:00
stream.c
sysctl_net_core.c
timestamping.c
tso.c
utils.c
xdp.c	bpf, xdp: Remove XDP_QUERY_PROG and XDP_QUERY_PROG_HW XDP commands	2020-07-25 20:37:02 -07:00