INFO: task kworker/u4:1:21 blocked for more than 143 seconds. Not tainted 5.9.0-rc8-next-20201007-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:1 state:D stack:25336 pid: 21 ppid: 2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:3773 [inline] __schedule+0xec5/0x2200 kernel/sched/core.c:4522 schedule+0xcf/0x270 kernel/sched/core.c:4600 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4659 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 cangw_pernet_exit+0xe/0x20 net/can/gw.c:1180 ops_exit_list+0xb0/0x160 net/core/net_namespace.c:187 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:604 process_one_work+0x933/0x15a0 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 INFO: task syz-executor.2:6890 blocked for more than 143 seconds. Not tainted 5.9.0-rc8-next-20201007-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:24016 pid: 6890 ppid: 1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:3773 [inline] __schedule+0xec5/0x2200 kernel/sched/core.c:4522 schedule+0xcf/0x270 kernel/sched/core.c:4600 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4659 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 tun_detach drivers/net/tun.c:687 [inline] tun_chr_close+0x3a/0x180 drivers/net/tun.c:3390 __fput+0x285/0x920 fs/file_table.c:281 task_work_run+0xdd/0x190 kernel/task_work.c:141 exit_task_work include/linux/task_work.h:25 [inline] do_exit+0xb23/0x2930 kernel/exit.c:806 do_group_exit+0x125/0x310 kernel/exit.c:903 __do_sys_exit_group kernel/exit.c:914 [inline] __se_sys_exit_group kernel/exit.c:912 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:912 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45de29 Code: Unable to access opcode bytes at RIP 0x45ddff. RSP: 002b:00007ffd7ca205d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000016 RCX: 000000000045de29 RDX: 00000000004176c1 RSI: 00000000016a9df0 RDI: 0000000000000000 RBP: 00000000004c290f R08: 000000000000000c R09: 0000000000000000 R10: 0000000002fb8940 R11: 0000000000000246 R12: 00007ffd7ca21880 R13: 0000000002fc1aa0 R14: 0000000000000000 R15: 00007ffd7ca22910 INFO: task syz-executor.4:8685 can't die for more than 144 seconds. task:syz-executor.4 state:D stack:26808 pid: 8685 ppid: 6894 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3773 [inline] __schedule+0xec5/0x2200 kernel/sched/core.c:4522 schedule+0xcf/0x270 kernel/sched/core.c:4600 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4659 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2489 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2362 ___sys_sendmsg+0xf3/0x170 net/socket.c:2416 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2449 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45de29 Code: Unable to access opcode bytes at RIP 0x45ddff. RSP: 002b:00007f7e3f4ccc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000002e5c0 RCX: 000000000045de29 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000003 RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffec8cf254f R14: 00007f7e3f4cd9c0 R15: 000000000118bf2c INFO: task syz-executor.4:8685 blocked for more than 144 seconds. Not tainted 5.9.0-rc8-next-20201007-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:26808 pid: 8685 ppid: 6894 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3773 [inline] __schedule+0xec5/0x2200 kernel/sched/core.c:4522 schedule+0xcf/0x270 kernel/sched/core.c:4600 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4659 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2489 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2362 ___sys_sendmsg+0xf3/0x170 net/socket.c:2416 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2449 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45de29 Code: Unable to access opcode bytes at RIP 0x45ddff. RSP: 002b:00007f7e3f4ccc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000002e5c0 RCX: 000000000045de29 RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000003 RBP: 000000000118bf60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118bf2c R13: 00007ffec8cf254f R14: 00007f7e3f4cd9c0 R15: 000000000118bf2c INFO: task syz-executor.4:8686 can't die for more than 145 seconds. task:syz-executor.4 state:R running task stack:23192 pid: 8686 ppid: 6894 flags:0x00004006 Call Trace: INFO: task syz-executor.4:8708 can't die for more than 145 seconds. task:syz-executor.4 state:D stack:28096 pid: 8708 ppid: 6894 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3773 [inline] __schedule+0xec5/0x2200 kernel/sched/core.c:4522 schedule+0xcf/0x270 kernel/sched/core.c:4600 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4659 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2489 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x331/0x810 net/socket.c:2362 ___sys_sendmsg+0xf3/0x170 net/socket.c:2416 __sys_sendmmsg+0x196/0x4b0 net/socket.c:2506 __do_sys_sendmmsg net/socket.c:2535 [inline] __se_sys_sendmmsg net/socket.c:2532 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2532 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45de29 Code: Unable to access opcode bytes at RIP 0x45ddff. RSP: 002b:00007f7e3f469c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000027f40 RCX: 000000000045de29 RDX: 04924924924926d3 RSI: 0000000020000200 RDI: 0000000000000005 RBP: 000000000118c160 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118c124 R13: 00007ffec8cf254f R14: 00007f7e3f46a9c0 R15: 000000000118c124 INFO: task syz-executor.4:8708 blocked for more than 146 seconds. Not tainted 5.9.0-rc8-next-20201007-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:28096 pid: 8708 ppid: 6894 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3773 [inline] __schedule+0xec5/0x2200 kernel/sched/core.c:4522 schedule+0xcf/0x270 kernel/sched/core.c:4600 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4659 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2489 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 ____sys_sendmsg+0x331/0x810 net/socket.c:2362 ___sys_sendmsg+0xf3/0x170 net/socket.c:2416 __sys_sendmmsg+0x196/0x4b0 net/socket.c:2506 __do_sys_sendmmsg net/socket.c:2535 [inline] __se_sys_sendmmsg net/socket.c:2532 [inline] __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2532 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45de29 Code: Unable to access opcode bytes at RIP 0x45ddff. RSP: 002b:00007f7e3f469c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000027f40 RCX: 000000000045de29 RDX: 04924924924926d3 RSI: 0000000020000200 RDI: 0000000000000005 RBP: 000000000118c160 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118c124 R13: 00007ffec8cf254f R14: 00007f7e3f46a9c0 R15: 000000000118c124 INFO: task syz-executor.3:8761 blocked for more than 146 seconds. Not tainted 5.9.0-rc8-next-20201007-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:28056 pid: 8761 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:3773 [inline] __schedule+0xec5/0x2200 kernel/sched/core.c:4522 schedule+0xcf/0x270 kernel/sched/core.c:4600 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4659 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x3e2/0x10e0 kernel/locking/mutex.c:1103 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2489 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:671 __sys_sendto+0x21c/0x320 net/socket.c:1992 __do_sys_sendto net/socket.c:2004 [inline] __se_sys_sendto net/socket.c:2000 [inline] __x64_sys_sendto+0xdd/0x1b0 net/socket.c:2000 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x4178a7 Code: Unable to access opcode bytes at RIP 0x41787d. RSP: 002b:00007ffe43428070 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000016a4300 RCX: 00000000004178a7 RDX: 0000000000000028 RSI: 00000000016a4350 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffe43428080 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00000000016a4350 R15: 0000000000000003 Showing all locks held in the system: 4 locks held by kworker/u4:1/21: #0: ffff88800fc1a138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88800fc1a138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff88800fc1a138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff88800fc1a138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff88800fc1a138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff88800fc1a138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2240 #1: ffffc90000dd7da8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2244 #2: ffffffff8b6bd1d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:566 #3: ffffffff8b6cecc8 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit+0xe/0x20 net/can/gw.c:1180 1 lock held by khungtaskd/1168: #0: ffffffff8a554de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6242 1 lock held by in:imklog/6565: #0: ffff8880108c08f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 1 lock held by syz-executor.2/6890: #0: ffffffff8b6cecc8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:687 [inline] #0: ffffffff8b6cecc8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x180 drivers/net/tun.c:3390 3 locks held by kworker/1:4/8137: #0: ffff88801fb47938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88801fb47938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff88801fb47938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff88801fb47938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff88801fb47938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff88801fb47938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2240 #1: ffffc900158a7da8 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2244 #2: ffffffff8b6cecc8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4568 1 lock held by syz-executor.4/8685: #0: ffffffff8b6cecc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8b6cecc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 2 locks held by syz-executor.4/8686: 1 lock held by syz-executor.4/8708: #0: ffffffff8b6cecc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8b6cecc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 1 lock held by syz-executor.3/8761: #0: ffffffff8b6cecc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8b6cecc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3f9/0xad0 net/core/rtnetlink.c:5560 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1168 Comm: khungtaskd Not tainted 5.9.0-rc8-next-20201007-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x198/0x1fb lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:147 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:253 [inline] watchdog+0xd89/0xf30 kernel/hung_task.c:339 kthread+0x3af/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3911 Comm: systemd-journal Not tainted 5.9.0-rc8-next-20201007-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0033:0x7f1adeaf50e3 Code: 00 00 00 48 8b 48 70 48 c1 e9 04 48 85 c9 0f 84 f2 01 00 00 31 d2 48 89 e8 48 f7 f1 48 c1 e2 04 48 03 93 d0 00 00 00 4c 8b 3a <4d> 85 ff 74 8a 48 8d 44 24 50 4c 8d 64 24 48 48 89 44 24 20 48 8d RSP: 002b:00007ffd76150690 EFLAGS: 00000206 RAX: 0000af88d477a858 RBX: 000055dc7f140e80 RCX: 00000000000117d5 RDX: 00007f1adc006fa0 RSI: 0000000000000000 RDI: 000055dc7f140e80 RBP: bfe02c6730077ad4 R08: 00007ffd76150768 R09: 00007ffd76150770 R10: 00007f1adeb1fee8 R11: 0000000000000246 R12: 000055dc7f140e80 R13: 0000000000000025 R14: 000055dc7f1415f0 R15: 0000000000000000 FS: 00007f1adee048c0 GS: 0000000000000000