bisecting fixing commit since 5b7a52cd2eef952cee8a72512ef370bcdef46636 building syzkaller on 94942294277bf7550b12322d282159551521258b testing commit 5b7a52cd2eef952cee8a72512ef370bcdef46636 with gcc (GCC) 8.4.1 20210217 kernel signature: 41195ae7275708d4bee54385676126f87aff1773d41ff0c88cdb0d46c080900f all runs: crashed: INFO: task hung in rtnl_lock testing current HEAD cf256fbcbe347b7d0ff58fe2dfa382a156bd3694 testing commit cf256fbcbe347b7d0ff58fe2dfa382a156bd3694 with gcc (GCC) 8.4.1 20210217 kernel signature: 8e5f8a392425688e923bb4d6aae71c28b60e222c4ae63d7dab044e7052a13cae all runs: crashed: INFO: task hung in rtnl_lock revisions tested: 2, total time: 31m23.841636462s (build: 16m57.00168816s, test: 14m1.382704164s) the crash still happens on HEAD commit msg: Linux 4.14.231 crash: INFO: task hung in rtnl_lock Bluetooth: hci5 command 0x0406 tx timeout Bluetooth: hci0 command 0x0406 tx timeout Bluetooth: hci3 command 0x0406 tx timeout Bluetooth: hci2 command 0x0406 tx timeout Bluetooth: hci4 command 0x0406 tx timeout INFO: task kworker/0:0:3 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:0 D26352 3 2 0x80000000 Workqueue: events disconnect_work Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 disconnect_work+0x16/0x1b0 net/wireless/sme.c:664 process_one_work+0x74f/0x1620 kernel/workqueue.c:2116 worker_thread+0xcc/0xee0 kernel/workqueue.c:2250 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 INFO: task kworker/1:2:3341 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:2 D26904 3341 2 0x80000000 Workqueue: events_power_efficient reg_check_chans_work Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 reg_check_chans_work+0x73/0xc60 net/wireless/reg.c:1655 process_one_work+0x74f/0x1620 kernel/workqueue.c:2116 worker_thread+0xcc/0xee0 kernel/workqueue.c:2250 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 INFO: task kworker/1:3:4052 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:3 D25696 4052 2 0x80000000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 addrconf_dad_work+0x8f/0xfa0 net/ipv6/addrconf.c:3918 process_one_work+0x74f/0x1620 kernel/workqueue.c:2116 worker_thread+0xcc/0xee0 kernel/workqueue.c:2250 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 INFO: task kworker/0:2:4330 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:2 D26304 4330 2 0x80000000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 addrconf_dad_work+0x8f/0xfa0 net/ipv6/addrconf.c:3918 process_one_work+0x74f/0x1620 kernel/workqueue.c:2116 worker_thread+0xcc/0xee0 kernel/workqueue.c:2250 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 INFO: task kworker/0:3:7489 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:3 D25744 7489 2 0x80000000 Workqueue: events linkwatch_event Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 linkwatch_event+0x9/0x50 net/core/link_watch.c:236 process_one_work+0x74f/0x1620 kernel/workqueue.c:2116 worker_thread+0xcc/0xee0 kernel/workqueue.c:2250 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 INFO: task syz-executor.4:7653 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D24920 7653 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x2c0/0x9e0 net/core/rtnetlink.c:4311 netlink_rcv_skb+0x12f/0x3b0 net/netlink/af_netlink.c:2433 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4328 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x40b/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x639/0xbe0 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:656 SYSC_sendto net/socket.c:1763 [inline] SyS_sendto+0x1e4/0x2c0 net/socket.c:1731 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418cdc RSP: 002b:00007ffe67571570 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000001494320 RCX: 0000000000418cdc RDX: 0000000000000028 RSI: 0000000001494370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffe675715b4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000001494370 INFO: task syz-executor.5:7655 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D24776 7655 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x2c0/0x9e0 net/core/rtnetlink.c:4311 netlink_rcv_skb+0x12f/0x3b0 net/netlink/af_netlink.c:2433 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4328 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x40b/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x639/0xbe0 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:656 SYSC_sendto net/socket.c:1763 [inline] SyS_sendto+0x1e4/0x2c0 net/socket.c:1731 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418cdc RSP: 002b:00007fff14d98440 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000001494320 RCX: 0000000000418cdc RDX: 0000000000000040 RSI: 0000000001494370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007fff14d98484 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000001494370 INFO: task syz-executor.0:7657 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D24736 7657 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x2c0/0x9e0 net/core/rtnetlink.c:4311 netlink_rcv_skb+0x12f/0x3b0 net/netlink/af_netlink.c:2433 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4328 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x40b/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x639/0xbe0 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:656 SYSC_sendto net/socket.c:1763 [inline] SyS_sendto+0x1e4/0x2c0 net/socket.c:1731 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418cdc RSP: 002b:00007ffe54a798e0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000001494320 RCX: 0000000000418cdc RDX: 0000000000000020 RSI: 0000000001494370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffe54a79924 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000001494370 INFO: task syz-executor.2:7658 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D24336 7658 1 0x00000004 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x2c0/0x9e0 net/core/rtnetlink.c:4311 netlink_rcv_skb+0x12f/0x3b0 net/netlink/af_netlink.c:2433 rtnetlink_rcv+0x10/0x20 net/core/rtnetlink.c:4328 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x40b/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x639/0xbe0 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:656 SYSC_sendto net/socket.c:1763 [inline] SyS_sendto+0x1e4/0x2c0 net/socket.c:1731 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x418cdc RSP: 002b:00007ffdab16cd20 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000001494320 RCX: 0000000000418cdc RDX: 0000000000000020 RSI: 0000000001494370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffdab16cd64 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000001494370 INFO: task kworker/1:4:8642 blocked for more than 140 seconds. Not tainted 4.14.231-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/1:4 D27496 8642 2 0x80000000 Workqueue: events wireless_nlevent_process Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x824/0x1ee0 kernel/sched/core.c:3384 schedule+0x7f/0x1b0 kernel/sched/core.c:3428 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3486 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x519/0x1490 kernel/locking/mutex.c:893 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908 rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 wireless_nlevent_process+0x9/0x20 net/wireless/wext-core.c:413 process_one_work+0x74f/0x1620 kernel/workqueue.c:2116 worker_thread+0xcc/0xee0 kernel/workqueue.c:2250 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Showing all locks held in the system: 3 locks held by kworker/0:0/3: #0: ("events"){+.+.}, at: [] process_one_work+0x681/0x1620 kernel/workqueue.c:2087 #1: (cfg80211_disconnect_work){+.+.}, at: [] process_one_work+0x6b4/0x1620 kernel/workqueue.c:2091 #2: (rtnl_mutex){+.+.}, at: [] rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 1 lock held by khungtaskd/1519: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4548 3 locks held by kworker/1:2/3341: #0: ("events_power_efficient"){+.+.}, at: [] process_one_work+0x681/0x1620 kernel/workqueue.c:2087 #1: ((reg_check_chans).work){+.+.}, at: [] process_one_work+0x6b4/0x1620 kernel/workqueue.c:2091 #2: (rtnl_mutex){+.+.}, at: [] rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 3 locks held by kworker/1:3/4052: #0: ("%s"("ipv6_addrconf")){+.+.}, at: [] process_one_work+0x681/0x1620 kernel/workqueue.c:2087 #1: ((&(&ifa->dad_work)->work)){+.+.}, at: [] process_one_work+0x6b4/0x1620 kernel/workqueue.c:2091 #2: (rtnl_mutex){+.+.}, at: [] rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 3 locks held by kworker/0:2/4330: #0: ("%s"("ipv6_addrconf")){+.+.}, at: [] process_one_work+0x681/0x1620 kernel/workqueue.c:2087 #1: ((&(&ifa->dad_work)->work)){+.+.}, at: [] process_one_work+0x6b4/0x1620 kernel/workqueue.c:2091 #2: (rtnl_mutex){+.+.}, at: [] rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 3 locks held by kworker/0:3/7489: #0: ("events"){+.+.}, at: [] process_one_work+0x681/0x1620 kernel/workqueue.c:2087 #1: ((linkwatch_work).work){+.+.}, at: [] process_one_work+0x6b4/0x1620 kernel/workqueue.c:2091 #2: (rtnl_mutex){+.+.}, at: [] rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 1 lock held by syz-executor.4/7653: #0: (rtnl_mutex){+.+.}, at: [] rtnl_lock net/core/rtnetlink.c:72 [inline] #0: (rtnl_mutex){+.+.}, at: [] rtnetlink_rcv_msg+0x2c0/0x9e0 net/core/rtnetlink.c:4311 1 lock held by syz-executor.5/7655: #0: (rtnl_mutex){+.+.}, at: [] rtnl_lock net/core/rtnetlink.c:72 [inline] #0: (rtnl_mutex){+.+.}, at: [] rtnetlink_rcv_msg+0x2c0/0x9e0 net/core/rtnetlink.c:4311 1 lock held by syz-executor.0/7657: #0: (rtnl_mutex){+.+.}, at: [] rtnl_lock net/core/rtnetlink.c:72 [inline] #0: (rtnl_mutex){+.+.}, at: [] rtnetlink_rcv_msg+0x2c0/0x9e0 net/core/rtnetlink.c:4311 1 lock held by syz-executor.2/7658: #0: (rtnl_mutex){+.+.}, at: [] rtnl_lock net/core/rtnetlink.c:72 [inline] #0: (rtnl_mutex){+.+.}, at: [] rtnetlink_rcv_msg+0x2c0/0x9e0 net/core/rtnetlink.c:4311 3 locks held by kworker/1:4/8642: #0: ("events"){+.+.}, at: [] process_one_work+0x681/0x1620 kernel/workqueue.c:2087 #1: (wireless_nlevent_work){+.+.}, at: [] process_one_work+0x6b4/0x1620 kernel/workqueue.c:2091 #2: (rtnl_mutex){+.+.}, at: [] rtnl_lock+0x12/0x20 net/core/rtnetlink.c:72 2 locks held by syz-executor.1/9087: #0: (cb_lock){++++}, at: [] genl_rcv+0x14/0x40 net/netlink/genetlink.c:635 #1: (genl_mutex){+.+.}, at: [] genl_lock net/netlink/genetlink.c:33 [inline] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:623 2 locks held by syz-executor.1/9097: #0: (cb_lock){++++}, at: [] genl_rcv+0x14/0x40 net/netlink/genetlink.c:635 #1: (genl_mutex){+.+.}, at: [] genl_lock net/netlink/genetlink.c:33 [inline] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:623 2 locks held by syz-executor.1/9098: #0: (cb_lock){++++}, at: [] genl_rcv+0x14/0x40 net/netlink/genetlink.c:635 #1: (genl_mutex){+.+.}, at: [] genl_lock net/netlink/genetlink.c:33 [inline] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:623 2 locks held by syz-executor.1/9099: #0: (cb_lock){++++}, at: [] genl_rcv+0x14/0x40 net/netlink/genetlink.c:635 #1: (genl_mutex){+.+.}, at: [] genl_lock net/netlink/genetlink.c:33 [inline] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:623 2 locks held by syz-executor.1/9101: #0: (cb_lock){++++}, at: [] genl_rcv+0x14/0x40 net/netlink/genetlink.c:635 #1: (genl_mutex){+.+.}, at: [] genl_lock net/netlink/genetlink.c:33 [inline] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:623 2 locks held by syz-executor.3/9094: #0: (cb_lock){++++}, at: [] genl_rcv+0x14/0x40 net/netlink/genetlink.c:635 #1: (genl_mutex){+.+.}, at: [] genl_lock net/netlink/genetlink.c:33 [inline] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:623 2 locks held by syz-executor.3/9095: #0: (cb_lock){++++}, at: [] genl_rcv+0x14/0x40 net/netlink/genetlink.c:635 #1: (genl_mutex){+.+.}, at: [] genl_lock net/netlink/genetlink.c:33 [inline] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:623 2 locks held by syz-executor.3/9096: #0: (cb_lock){++++}, at: [] genl_rcv+0x14/0x40 net/netlink/genetlink.c:635 #1: (genl_mutex){+.+.}, at: [] genl_lock net/netlink/genetlink.c:33 [inline] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:623 2 locks held by syz-executor.3/9102: #0: (cb_lock){++++}, at: [] genl_rcv+0x14/0x40 net/netlink/genetlink.c:635 #1: (genl_mutex){+.+.}, at: [] genl_lock net/netlink/genetlink.c:33 [inline] #1: (genl_mutex){+.+.}, at: [] genl_rcv_msg+0x10e/0x140 net/netlink/genetlink.c:623 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1519 Comm: khungtaskd Not tainted 4.14.231-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x14b/0x1e7 lib/dump_stack.c:58 nmi_cpu_backtrace.cold.0+0x3c/0x78 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xf6/0x120 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x51b/0xa70 kernel/hung_task.c:274 kthread+0x338/0x400 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9080 Comm: syz-executor.1 Not tainted 4.14.231-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8881edfc41c0 task.stack: ffff8881d8790000 RIP: 0010:ieee80211_chanctx_radar_detect+0x1a6/0x340 net/mac80211/util.c:3349 RSP: 0018:ffff8881d87972f8 EFLAGS: 00000a06 RAX: 0000000000000000 RBX: ffff8881d3aa5d40 RCX: 1ffff1103cbf13e4 RDX: 1ffff1103a754cc9 RSI: 0000000000000000 RDI: ffff8881d3aa6648 RBP: ffff8881d8797328 R08: 1ffff1103dbf8948 R09: ffff8881d3aa5d40 R10: ffff8881d8797428 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff8881e5f89f20 R14: ffff8881e5f89f00 R15: 0000000000000000 FS: 00007f9baac49700(0000) GS:ffff8881f6500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe72b2e2018 CR3: 00000001ebeed003 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ieee80211_check_combinations+0x2e3/0x9b0 net/mac80211/util.c:3408 ieee80211_check_concurrent_iface+0x3a9/0x640 net/mac80211/iface.c:311 ieee80211_runtime_change_iftype net/mac80211/iface.c:1558 [inline] ieee80211_if_change_type+0x23b/0x4b0 net/mac80211/iface.c:1602 ieee80211_change_iface+0x29/0x1e0 net/mac80211/cfg.c:156 rdev_change_virtual_intf net/wireless/rdev-ops.h:69 [inline] cfg80211_change_iface+0x200/0x1160 net/wireless/util.c:1048 nl80211_set_interface+0x443/0x840 net/wireless/nl80211.c:2929 genl_family_rcv_msg+0x57f/0xfe0 net/netlink/genetlink.c:600 genl_rcv_msg+0xa7/0x140 net/netlink/genetlink.c:625 netlink_rcv_skb+0x12f/0x3b0 net/netlink/af_netlink.c:2433 genl_rcv+0x23/0x40 net/netlink/genetlink.c:636 netlink_unicast_kernel net/netlink/af_netlink.c:1287 [inline] netlink_unicast+0x40b/0x610 net/netlink/af_netlink.c:1313 netlink_sendmsg+0x639/0xbe0 net/netlink/af_netlink.c:1878 sock_sendmsg_nosec net/socket.c:646 [inline] sock_sendmsg+0xac/0xf0 net/socket.c:656 ___sys_sendmsg+0x625/0x920 net/socket.c:2062 __sys_sendmsg+0xc1/0x140 net/socket.c:2096 SYSC_sendmsg net/socket.c:2107 [inline] SyS_sendmsg+0xd/0x20 net/socket.c:2103 do_syscall_64+0x1c7/0x5b0 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x465849 RSP: 002b:00007f9baac49188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000055bf00 RCX: 0000000000465849 RDX: 0000000000000000 RSI: 0000000020000340 RDI: 0000000000000004 RBP: 00000000004af675 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000055bf00 R13: 00007ffd9d56685f R14: 00007f9baac49300 R15: 0000000000022000 Code: 8b 56 20 48 8d 9a 20 f8 ff ff 49 39 d5 0f 84 90 00 00 00 49 bc 00 00 00 00 00 fc ff df 48 8d bb 08 09 00 00 48 89 fa 48 c1 ea 03 <42> 0f b6 14 22 84 d2 74 06 0f 8e ff 00 00 00 80 bb 08 09 00 00