INFO: task syz-executor.3:29081 blocked for more than 143 seconds. Not tainted 5.11.0-rc4-next-20210121-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.3 state:D stack:28424 pid:29081 ppid: 8471 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:4373 [inline] __schedule+0x90c/0x21a0 kernel/sched/core.c:5124 schedule+0xcf/0x270 kernel/sched/core.c:5203 rwsem_down_write_slowpath+0x7e5/0x1200 kernel/locking/rwsem.c:1106 __down_write_common kernel/locking/rwsem.c:1261 [inline] __down_write_common kernel/locking/rwsem.c:1258 [inline] __down_write kernel/locking/rwsem.c:1270 [inline] down_write+0x132/0x150 kernel/locking/rwsem.c:1407 unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1868 bcm_release+0x94/0x750 net/can/bcm.c:1472 __sock_release+0xcd/0x280 net/socket.c:597 sock_close+0x18/0x20 net/socket.c:1256 __fput+0x283/0x920 fs/file_table.c:280 task_work_run+0xdd/0x190 kernel/task_work.c:140 exit_task_work include/linux/task_work.h:30 [inline] do_exit+0xc5c/0x2ae0 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 get_signal+0x427/0x20f0 kernel/signal.c:2773 arch_do_signal_or_restart+0x2a8/0x1eb0 arch/x86/kernel/signal.c:811 handle_signal_work kernel/entry/common.c:150 [inline] exit_to_user_mode_loop kernel/entry/common.c:174 [inline] exit_to_user_mode_prepare+0x148/0x250 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:301 [inline] syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:312 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e219 RSP: 002b:00007fad29457c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: 0000000000000003 RBX: 0000000000000003 RCX: 000000000045e219 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d RBP: 000000000119bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c R13: 00007ffc2ff7574f R14: 00007fad294589c0 R15: 000000000119bf8c Showing all locks held in the system: 3 locks held by kworker/u4:1/25: 1 lock held by khungtaskd/1666: #0: ffffffff8b370ea0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6326 1 lock held by in:imklog/8150: #0: ffff888014ea19f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:947 2 locks held by syz-executor.3/29081: #0: ffff88807a81e190 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:773 [inline] #0: ffff88807a81e190 (&sb->s_type->i_mutex_key#12){+.+.}-{3:3}, at: __sock_release+0x86/0x280 net/socket.c:596 #1: ffffffff8ca54ad0 (pernet_ops_rwsem){++++}-{3:3}, at: unregister_netdevice_notifier+0x1e/0x170 net/core/dev.c:1868 1 lock held by syz-executor.2/29382: #0: ffffffff8ca54ad0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:479 1 lock held by syz-executor.3/29390: #0: ffffffff8ca54ad0 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2fa/0x760 net/core/net_namespace.c:479 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1666 Comm: khungtaskd Not tainted 5.11.0-rc4-next-20210121-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x107/0x163 lib/dump_stack.c:120 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:338 kthread+0x3b1/0x4a0 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: 25 Comm: kworker/u4:1 Not tainted 5.11.0-rc4-next-20210121-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:kasan_mem_to_shadow include/linux/kasan.h:53 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:177 [inline] RIP: 0010:kasan_check_range+0x44/0x180 mm/kasan/generic.c:186 Code: 01 00 00 48 b8 ff ff ff ff ff 7f ff ff 48 39 c7 0f 86 05 01 00 00 49 83 e9 01 48 89 fd 48 b8 00 00 00 00 00 fc ff df 4d 89 ca <48> c1 ed 03 49 c1 ea 03 48 01 c5 49 01 c2 48 89 e8 49 8d 5a 01 48 RSP: 0018:ffffc90000dffa78 EFLAGS: 00000292 RAX: dffffc0000000000 RBX: 1ffff920001bff55 RCX: ffffffff8158e248 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8d049448 RBP: ffffffff8d049448 R08: 0000000000000000 R09: ffffffff8d04944f R10: ffffffff8d04944f R11: 0000000000000000 R12: 0000000000000000 R13: ffffffff8b06aa98 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feeb89cc018 CR3: 00000000132a3000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] cpumask_test_cpu include/linux/cpumask.h:373 [inline] trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0xb8/0x720 kernel/locking/lockdep.c:5480 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] nf_conntrack_lock net/netfilter/nf_conntrack_core.c:91 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2199 [inline] nf_ct_iterate_cleanup+0x183/0x400 net/netfilter/nf_conntrack_core.c:2244 nf_conntrack_cleanup_net_list+0x81/0x250 net/netfilter/nf_conntrack_core.c:2431 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:190 cleanup_net+0x4ea/0xb10 net/core/net_namespace.c:604 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421 kthread+0x3b1/0x4a0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296