linux/net/core
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 net: use indirect call wrappers for skb_copy_datagram_iter() 2020-03-25 11:30:40 -07:00
datagram.h
dev.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-03 18:50:48 -07:00
dev_addr_lists.c net: explain the lockdep annotations for dev_uc_unsync() 2020-06-28 21:38:27 -07:00
dev_ioctl.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
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.c net/dst: use a smaller percpu_counter batch for dst entries accounting 2020-05-08 21:33:33 -07:00
dst_cache.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 net/flow_dissector: add packet hash dissection 2020-07-24 15:23:31 -07:00
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 docs: networking: convert gen_stats.txt to ReST 2020-04-28 14:39:46 -07:00
gro_cells.c
hwbm.c
link_watch.c net: Add IF_OPER_TESTING 2020-04-20 12:43:24 -07:00
lwt_bpf.c net: add net available in build_state 2020-03-29 22:30:57 -07:00
lwtunnel.c net: ipv6: add rpl sr tunnel 2020-03-29 22:30:57 -07:00
Makefile ethtool: move to its own directory 2019-12-12 17:07:05 -08:00
neighbour.c net: neighbor: add fdb extended attribute 2020-06-24 14:36:33 -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-sysfs: add netdev_change_owner() 2020-02-26 20:07:25 -08:00
net-traces.c
net_namespace.c Revert "netns: don't disable BHs when locking "nsid_lock"" 2020-09-07 14:32:39 -07:00
netclassid_cgroup.c cgroup, netclassid: remove double cond_resched 2020-04-21 15:44:30 -07:00
netevent.c
netpoll.c net: disable netpoll on fresh napis 2020-08-26 16:16:39 -07:00
netprio_cgroup.c netprio_cgroup: Fix unlimited memory leak of v2 cgroups 2020-05-09 20:59:21 -07:00
page_pool.c net: page pool: allow to pass zero flags to page_pool_init() 2020-03-29 21:49:20 -07:00
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 fs: Add receive_fd() wrapper for __receive_fd() 2020-07-13 11:03:44 -07:00
secure_seq.c crypto: lib/sha1 - remove unnecessary includes of linux/cryptohash.h 2020-05-08 15:32:17 +10:00
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.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-09-03 18:50:48 -07:00
sock_diag.c
sock_map.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-07-11 00:46:00 -07:00
sock_reuseport.c udp: Copy has_conns in reuseport_grow(). 2020-07-21 15:31:02 -07:00
stream.c
sysctl_net_core.c bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok() 2020-07-08 16:01:21 -07:00
timestamping.c net: Introduce a new MII time stamping interface. 2019-12-25 19:51:33 -08:00
tso.c net: tso: add UDP segmentation support 2020-06-18 20:46:23 -07:00
utils.c net: Fix skb->csum update in inet_proto_csum_replace16(). 2020-01-24 20:54:30 +01:00
xdp.c bpf, xdp: Remove XDP_QUERY_PROG and XDP_QUERY_PROG_HW XDP commands 2020-07-25 20:37:02 -07:00