INFO: task syz-executor3:16870 blocked for more than 140 seconds. Not tainted 4.9.140+ #3 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. audit_printk_skb: 1047 callbacks suppressed audit: type=1400 audit(1543342866.428:19605): avc: denied { sys_admin } for pid=2100 comm="syz-executor0" capability=21 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 audit: type=1400 audit(1543342866.428:19606): avc: denied { sys_admin } for pid=2100 comm="syz-executor0" capability=21 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 audit: type=1400 audit(1543342866.428:19607): avc: denied { net_admin } for pid=2100 comm="syz-executor0" capability=12 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 audit: type=1400 audit(1543342866.428:19608): avc: denied { net_admin } for pid=2100 comm="syz-executor0" capability=12 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 audit: type=1400 audit(1543342866.428:19609): avc: denied { net_admin } for pid=2100 comm="syz-executor0" capability=12 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 audit: type=1400 audit(1543342866.468:19610): avc: denied { dac_override } for pid=27353 comm="syz-executor1" capability=1 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 audit: type=1400 audit(1543342866.478:19611): avc: denied { dac_override } for pid=27353 comm="syz-executor1" capability=1 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 audit: type=1400 audit(1543342866.498:19612): avc: denied { sys_admin } for pid=2101 comm="syz-executor1" capability=21 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 audit: type=1400 audit(1543342866.498:19613): avc: denied { sys_admin } for pid=2101 comm="syz-executor1" capability=21 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 audit: type=1400 audit(1543342866.498:19614): avc: denied { net_admin } for pid=2101 comm="syz-executor1" capability=12 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 netlink: 49 bytes leftover after parsing attributes in process `syz-executor3'. syz-executor3 D28488 16870 2102 0x00000000 ffff8801d9ba17c0 ffff8801a80cdd80 ffff8801cf241080 ffff8801a80f5f00 ffff8801db721018 ffff8801d20f7840 ffffffff82807402 ffff8801cf241080 ffffffff83cd80a0 ffff8801d20f7860 0000000000002438 ffff8801db7218f0 Call Trace: [] schedule+0x7f/0x1b0 kernel/sched/core.c:3553 [] schedule_timeout+0x735/0xe20 kernel/time/timer.c:1771 [] down_read_failed drivers/tty/tty_ldsem.c:241 [inline] [] __ldsem_down_read_nested+0x33c/0x610 drivers/tty/tty_ldsem.c:332 [] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367 [] tty_ldisc_ref_wait+0x25/0x80 drivers/tty/tty_ldisc.c:275 [] tty_ioctl+0x3b6/0x2190 drivers/tty/tty_io.c:3009 [] vfs_ioctl fs/ioctl.c:43 [inline] [] file_ioctl fs/ioctl.c:493 [inline] [] do_vfs_ioctl+0x1ac/0x11a0 fs/ioctl.c:677 [] SYSC_ioctl fs/ioctl.c:694 [inline] [] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 [] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Showing all locks held in the system: 2 locks held by kworker/0:0/4: #0: ("events"){.+.+.+}, at: [] process_one_work+0x73c/0x15f0 kernel/workqueue.c:2085 #1: ((&ns->proc_work)){+.+...}, at: [] process_one_work+0x774/0x15f0 kernel/workqueue.c:2089 2 locks held by khungtaskd/24: #0: (rcu_read_lock){......}, at: [] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline] #0: (rcu_read_lock){......}, at: [] watchdog+0x11c/0xa20 kernel/hung_task.c:239 #1: (tasklist_lock){.+.+..}, at: [] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336 1 lock held by rsyslogd/1898: #0: (&f->f_pos_lock){+.+.+.}, at: [] __fdget_pos+0xac/0xd0 fs/file.c:781 2 locks held by getty/2025: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142 5 locks held by kworker/u4:4/2244: #0: ("%s""netns"){.+.+.+}, at: [] process_one_work+0x73c/0x15f0 kernel/workqueue.c:2085 #1: (net_cleanup_work){+.+.+.}, at: [] process_one_work+0x774/0x15f0 kernel/workqueue.c:2089 #2: (net_mutex){+.+.+.}, at: [] cleanup_net+0x13f/0x8b0 net/core/net_namespace.c:439 #3: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 #4: (rcu_preempt_state.exp_mutex){+.+...}, at: [] exp_funnel_lock kernel/rcu/tree_exp.h:256 [inline] #4: (rcu_preempt_state.exp_mutex){+.+...}, at: [] _synchronize_rcu_expedited+0x339/0x840 kernel/rcu/tree_exp.h:569 2 locks held by syz-executor3/16869: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367 #1: (&ldata->atomic_read_lock){+.+...}, at: [] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142 1 lock held by syz-executor3/16870: #0: (&tty->ldisc_sem){++++++}, at: [] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367 2 locks held by kworker/0:2/23701: #0: ("events"){.+.+.+}, at: [] process_one_work+0x73c/0x15f0 kernel/workqueue.c:2085 #1: ((&rew.rew_work)){+.+...}, at: [] process_one_work+0x774/0x15f0 kernel/workqueue.c:2089 1 lock held by syz-executor0/26642: #0: (&sig->cred_guard_mutex){+.+.+.}, at: [] prepare_bprm_creds+0x53/0x110 fs/exec.c:1369 1 lock held by syz-executor3/27376: #0: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock net/core/rtnetlink.c:70 [inline] #0: (rtnl_mutex){+.+.+.}, at: [] rtnetlink_rcv+0x1b/0x40 net/core/rtnetlink.c:4083 1 lock held by syz-executor4/27391: #0: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 24 Comm: khungtaskd Not tainted 4.9.140+ #3 ffff8801d9907d08 ffffffff81b42e79 0000000000000000 0000000000000000 0000000000000000 0000000000000001 ffffffff810983b0 ffff8801d9907d40 ffffffff81b4df89 0000000000000000 0000000000000000 0000000000000002 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] nmi_cpu_backtrace.cold.0+0x48/0x87 lib/nmi_backtrace.c:99 [] nmi_trigger_cpumask_backtrace+0x12c/0x151 lib/nmi_backtrace.c:60 [] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 [] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline] [] check_hung_task kernel/hung_task.c:125 [inline] [] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline] [] watchdog+0x6ad/0xa20 kernel/hung_task.c:239 [] kthread+0x26d/0x300 kernel/kthread.c:211 [] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1895 Comm: rs:main Q:Reg Not tainted 4.9.140+ #3 task: ffff8801d3ae4740 task.stack: ffff8801d3110000 RIP: 0033:[<000000000041a0c0>] c [<000000000041a0c0>] 0x41a0c0 RSP: 002b:00007f1dd1061478 EFLAGS: 00000207 RAX: 000000000041b378 RBX: 0000000001cfb5f0 RCX: 0000000001cfac70 RDX: fffffffffffd5b58 RSI: 0000000000000002 RDI: 0000000001cfb5f0 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000002 R10: 00007f1dd1061650 R11: 000000000001a520 R12: 0000000001cfb5f0 R13: 0000000001cfac50 R14: 0000000001cd3a40 R15: 0000000001cfac50 FS: 00007f1dd1062700(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556136eb2a98 CR3: 00000001d46e0000 CR4: 00000000001606b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400