syzbot


possible deadlock in dev_mc_sync

Status: auto-closed as invalid on 2021/01/08 21:25
Subsystems: net
[Documentation on labels]
Reported-by: syzbot+4d35bd6ecc37bccfd165@syzkaller.appspotmail.com
First crash: 1370d, last: 1295d
Discussions (1)
Title Replies (including bot) Last reply
possible deadlock in dev_mc_sync 0 (1) 2020/06/27 20:41
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 possible deadlock in dev_mc_sync (2) 2 560d 578d 0/1 auto-obsoleted due to no activity on 2023/01/14 06:46
linux-4.19 possible deadlock in dev_mc_sync 1 791d 791d 0/1 auto-closed as invalid on 2022/05/28 09:02

Sample crash report:
batman_adv: batadv0: Interface deactivated: batadv_slave_1
batman_adv: batadv0: Removing interface: batadv_slave_1
device bridge_slave_1 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
device bridge_slave_0 left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
============================================
WARNING: possible recursive locking detected
5.9.0-rc4-syzkaller #0 Not tainted
--------------------------------------------
kworker/u4:6/23980 is trying to acquire lock:
ffff888044790280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: netif_addr_lock_nested include/linux/netdevice.h:4266 [inline]
ffff888044790280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_sync+0xad/0x190 net/core/dev_addr_lists.c:870

but task is already holding lock:
ffff88804bc8a280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: netif_addr_lock_nested include/linux/netdevice.h:4266 [inline]
ffff88804bc8a280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_unsync+0xca/0x1b0 net/core/dev_addr_lists.c:925

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&vlan_netdev_addr_lock_key/1);
  lock(&vlan_netdev_addr_lock_key/1);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

6 locks held by kworker/u4:6/23980:
 #0: ffff8880a9bbc938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x6f4/0xfc0 kernel/workqueue.c:2242
 #1: ffffc90012f87d80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x733/0xfc0 kernel/workqueue.c:2244
 #2: ffffffff897d3ff0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xac/0xba0 net/core/net_namespace.c:565
 #3: ffffffff897d5d68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock_unregistering net/core/dev.c:10865 [inline]
 #3: ffffffff897d5d68 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0x124/0x6b0 net/core/dev.c:10903
 #4: ffff888093cf8280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:359 [inline]
 #4: ffff888093cf8280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: netif_addr_lock_bh include/linux/netdevice.h:4271 [inline]
 #4: ffff888093cf8280 (&vlan_netdev_addr_lock_key){+...}-{2:2}, at: dev_mc_unsync+0x8d/0x1b0 net/core/dev_addr_lists.c:924
 #5: ffff88804bc8a280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: netif_addr_lock_nested include/linux/netdevice.h:4266 [inline]
 #5: ffff88804bc8a280 (&vlan_netdev_addr_lock_key/1){+...}-{2:2}, at: dev_mc_unsync+0xca/0x1b0 net/core/dev_addr_lists.c:925

stack backtrace:
CPU: 0 PID: 23980 Comm: kworker/u4:6 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d6/0x29e lib/dump_stack.c:118
 print_deadlock_bug kernel/locking/lockdep.c:2391 [inline]
 check_deadlock kernel/locking/lockdep.c:2432 [inline]
 validate_chain+0x69a4/0x88a0 kernel/locking/lockdep.c:3202
 __lock_acquire+0x110b/0x2ae0 kernel/locking/lockdep.c:4426
 lock_acquire+0x140/0x6f0 kernel/locking/lockdep.c:5006
 _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:361
 netif_addr_lock_nested include/linux/netdevice.h:4266 [inline]
 dev_mc_sync+0xad/0x190 net/core/dev_addr_lists.c:870
 vlan_dev_set_rx_mode+0x47/0x70 net/8021q/vlan_dev.c:487
 dev_mc_unsync+0x105/0x1b0 net/core/dev_addr_lists.c:927
 vlan_dev_stop+0x47/0x320 net/8021q/vlan_dev.c:315
 __dev_close_many+0x2b2/0x390 net/core/dev.c:1605
 dev_close_many+0x1c1/0x4d0 net/core/dev.c:1630
 rollback_registered_many+0x454/0x1380 net/core/dev.c:9261
 unregister_netdevice_many net/core/dev.c:10429 [inline]
 default_device_exit_batch+0x42f/0x6b0 net/core/dev.c:10912
 ops_exit_list net/core/net_namespace.c:189 [inline]
 cleanup_net+0x79c/0xba0 net/core/net_namespace.c:603
 process_one_work+0x789/0xfc0 kernel/workqueue.c:2269
 worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415
 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
device veth1_macvtap left promiscuous mode
device veth0_macvtap left promiscuous mode
device veth1_vlan left promiscuous mode
device veth0_vlan left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
bond0 (unregistering): Released all slaves
tipc: TX() has been purged, node left!
device hsr_slave_0 left promiscuous mode
device hsr_slave_1 left promiscuous mode
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
batman_adv: batadv0: Removing interface: batadv_slave_1
device bridge_slave_1 left promiscuous mode
bridge0: port 2(bridge_slave_1) entered disabled state
device bridge_slave_0 left promiscuous mode
bridge0: port 1(bridge_slave_0) entered disabled state
device veth1_macvtap left promiscuous mode
device veth0_macvtap left promiscuous mode
device veth1_vlan left promiscuous mode
device veth0_vlan left promiscuous mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed
bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
bond0 (unregistering): Released all slaves

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/09/10 21:24 upstream 7fe10096c150 409809d8 .config console log report ci-upstream-kasan-gce-smack-root
2020/07/13 03:36 upstream 4437dd6e8f71 9ebcc5b1 .config console log report ci-upstream-kasan-gce-smack-root
2020/08/02 02:40 net-old fda2ec62cf1a d895b3be .config console log report ci-upstream-net-this-kasan-gce
2020/06/27 16:28 net-old 4a21185cda0f ffec44b5 .config console log report ci-upstream-net-this-kasan-gce
2020/06/27 17:40 net-next-old 7bed14551659 ffec44b5 .config console log report ci-upstream-net-kasan-gce
* Struck through repros no longer work on HEAD.