syzbot


possible deadlock in ieee80211_remove_interfaces

Status: upstream: reported on 2024/09/05 20:10
Subsystems: wireless
[Documentation on labels]
Reported-by: syzbot+5b9196ecf74447172a9a@syzkaller.appspotmail.com
First crash: 62d, last: 6d04h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [wireless?] possible deadlock in ieee80211_remove_interfaces 0 (1) 2024/09/05 20:10

Sample crash report:
======================================================
WARNING: possible circular locking dependency detected
6.12.0-rc4-syzkaller-00289-gea1fda89f5b2 #0 Not tainted
------------------------------------------------------
kworker/u32:7/1134 is trying to acquire lock:

but task is already holding lock:
ffff888035e70768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:6014 [inline]
ffff888035e70768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: ieee80211_remove_interfaces+0xfe/0x760 net/mac80211/iface.c:2275

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&rdev->wiphy.mtx){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
       wiphy_lock include/net/cfg80211.h:6014 [inline]
       ieee80211_open+0x12f/0x260 net/mac80211/iface.c:449
       __dev_open+0x2d4/0x4e0 net/core/dev.c:1476
       dev_open net/core/dev.c:1512 [inline]
       dev_open+0xf4/0x160 net/core/dev.c:1505
       team_port_add drivers/net/team/team_core.c:1216 [inline]
       team_add_slave+0xacd/0x20e0 drivers/net/team/team_core.c:1976
       do_set_master+0x1bc/0x230 net/core/rtnetlink.c:2730
       do_setlink+0xd24/0x41c0 net/core/rtnetlink.c:2936
       __rtnl_newlink+0xc35/0x1920 net/core/rtnetlink.c:3725
       rtnl_newlink+0x67/0xa0 net/core/rtnetlink.c:3772
       rtnetlink_rcv_msg+0x3c7/0xea0 net/core/rtnetlink.c:6675
       netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2551
       netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
       netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357
       netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901
       sock_sendmsg_nosec net/socket.c:729 [inline]
       __sock_sendmsg net/socket.c:744 [inline]
       ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2607
       ___sys_sendmsg+0x135/0x1e0 net/socket.c:2661
       __sys_sendmsg+0x117/0x1f0 net/socket.c:2690
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (team->team_lock_key#7){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3161 [inline]
       check_prevs_add kernel/locking/lockdep.c:3280 [inline]
       validate_chain kernel/locking/lockdep.c:3904 [inline]
       __lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5202
       lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825
       __mutex_lock_common kernel/locking/mutex.c:608 [inline]
       __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
       team_del_slave+0x31/0x1b0 drivers/net/team/team_core.c:1990
       team_device_event+0xd0/0x770 drivers/net/team/team_core.c:2984
       notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
       call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1996
       call_netdevice_notifiers_extack net/core/dev.c:2034 [inline]
       call_netdevice_notifiers net/core/dev.c:2048 [inline]
       unregister_netdevice_many_notify+0x8d5/0x1e50 net/core/dev.c:11403
       unregister_netdevice_many net/core/dev.c:11465 [inline]
       unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11339
       unregister_netdevice include/linux/netdevice.h:3118 [inline]
       _cfg80211_unregister_wdev+0x624/0x7f0 net/wireless/core.c:1211
       ieee80211_remove_interfaces+0x36d/0x760 net/mac80211/iface.c:2300
       ieee80211_unregister_hw+0x55/0x3a0 net/mac80211/main.c:1669
       mac80211_hwsim_del_radio drivers/net/wireless/virtual/mac80211_hwsim.c:5625 [inline]
       hwsim_exit_net+0x3ad/0x7d0 drivers/net/wireless/virtual/mac80211_hwsim.c:6505
       ops_exit_list+0xb0/0x180 net/core/net_namespace.c:173
       cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
       process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
       process_scheduled_works kernel/workqueue.c:3310 [inline]
       worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
       kthread+0x2c1/0x3a0 kernel/kthread.c:389
       ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&rdev->wiphy.mtx);
                               lock(team->team_lock_key#7);
                               lock(&rdev->wiphy.mtx);
  lock(team->team_lock_key#7);

 *** DEADLOCK ***

5 locks held by kworker/u32:7/1134:
 #0: ffff88801befc948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x129b/0x1ba0 kernel/workqueue.c:3204
 #1: ffffc90005b87d80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205
 #2: ffffffff8fecd0d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xbb/0xb40 net/core/net_namespace.c:580
 #3: ffffffff8fee2a68 (rtnl_mutex){+.+.}-{3:3}, at: ieee80211_unregister_hw+0x4d/0x3a0 net/mac80211/main.c:1662
 #4: ffff888035e70768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:6014 [inline]
 #4: ffff888035e70768 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: ieee80211_remove_interfaces+0xfe/0x760 net/mac80211/iface.c:2275

stack backtrace:
CPU: 0 UID: 0 PID: 1134 Comm: kworker/u32:7 Not tainted 6.12.0-rc4-syzkaller-00289-gea1fda89f5b2 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_circular_bug+0x41c/0x610 kernel/locking/lockdep.c:2074
 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2206
 check_prev_add kernel/locking/lockdep.c:3161 [inline]
 check_prevs_add kernel/locking/lockdep.c:3280 [inline]
 validate_chain kernel/locking/lockdep.c:3904 [inline]
 __lock_acquire+0x250b/0x3ce0 kernel/locking/lockdep.c:5202
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5825
 __mutex_lock_common kernel/locking/mutex.c:608 [inline]
 __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752
 team_del_slave+0x31/0x1b0 drivers/net/team/team_core.c:1990
 team_device_event+0xd0/0x770 drivers/net/team/team_core.c:2984
 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93
 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1996
 call_netdevice_notifiers_extack net/core/dev.c:2034 [inline]
 call_netdevice_notifiers net/core/dev.c:2048 [inline]
 unregister_netdevice_many_notify+0x8d5/0x1e50 net/core/dev.c:11403
 unregister_netdevice_many net/core/dev.c:11465 [inline]
 unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11339
 unregister_netdevice include/linux/netdevice.h:3118 [inline]
 _cfg80211_unregister_wdev+0x624/0x7f0 net/wireless/core.c:1211
 ieee80211_remove_interfaces+0x36d/0x760 net/mac80211/iface.c:2300
 ieee80211_unregister_hw+0x55/0x3a0 net/mac80211/main.c:1669
 mac80211_hwsim_del_radio drivers/net/wireless/virtual/mac80211_hwsim.c:5625 [inline]
 hwsim_exit_net+0x3ad/0x7d0 drivers/net/wireless/virtual/mac80211_hwsim.c:6505
 ops_exit_list+0xb0/0x180 net/core/net_namespace.c:173
 cleanup_net+0x5b7/0xb40 net/core/net_namespace.c:626
 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3229
 process_scheduled_works kernel/workqueue.c:3310 [inline]
 worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/28 07:07 upstream ea1fda89f5b2 65e8686b .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream possible deadlock in ieee80211_remove_interfaces
2024/09/01 20:01 upstream 431c1646e1f8 1eda0d14 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream possible deadlock in ieee80211_remove_interfaces
* Struck through repros no longer work on HEAD.