INFO: task syz-executor.3:4361 blocked for more than 140 seconds. Not tainted 4.9.194+ #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28280 4361 2105 0x80000002 0000000000000087 ffff88019e97af80 0000000000000000 ffff8801db721000 ffff8801da6f2f80 ffff8801db721018 ffff8801adf6f7a8 ffffffff8281af8e 0000000000000286 0000000000000000 00ff88019e97af80 ffff8801db7218f0 Call Trace: [<00000000758a091e>] schedule+0x92/0x1c0 kernel/sched/core.c:3546 [<000000004935e387>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3579 [<00000000733e5ed0>] __mutex_lock_common kernel/locking/mutex.c:582 [inline] [<00000000733e5ed0>] mutex_lock_nested+0x38d/0x920 kernel/locking/mutex.c:621 [<00000000455b1671>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 [<00000000865a9459>] ipv6_sock_mc_close+0xb0/0xe0 net/ipv6/mcast.c:313 [<00000000fbf5641b>] inet6_release+0x43/0x80 net/ipv6/af_inet6.c:450 [<00000000f5f387cb>] __sock_release+0xd3/0x2c0 net/socket.c:605 [<000000001cb79a66>] sock_close+0x1b/0x30 net/socket.c:1060 [<00000000b1cb834e>] __fput+0x274/0x720 fs/file_table.c:208 [<00000000132b4616>] ____fput+0x16/0x20 fs/file_table.c:244 [<000000009a18b561>] task_work_run+0x108/0x180 kernel/task_work.c:116 [<0000000041442a7b>] exit_task_work include/linux/task_work.h:21 [inline] [<0000000041442a7b>] do_exit+0x78f/0x2aa0 kernel/exit.c:842 [<0000000019141c1b>] do_group_exit+0x111/0x300 kernel/exit.c:946 [<0000000095351c3f>] get_signal+0x377/0x1cb0 kernel/signal.c:2395 [<000000004ff10603>] do_signal+0x9c/0x1920 arch/x86/kernel/signal.c:812 [<000000002365890d>] exit_to_usermode_loop+0x11c/0x160 arch/x86/entry/common.c:159 [<00000000c17e0993>] prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] [<00000000c17e0993>] syscall_return_slowpath arch/x86/entry/common.c:266 [inline] [<00000000c17e0993>] do_syscall_64+0x3ab/0x5c0 arch/x86/entry/common.c:293 [<0000000052f2366f>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Showing all locks held in the system: 2 locks held by khungtaskd/24: #0: (rcu_read_lock){......}, at: [<00000000f485ef62>] check_hung_uninterruptible_tasks kernel/hung_task.c:169 [inline] #0: (rcu_read_lock){......}, at: [<00000000f485ef62>] watchdog+0x14b/0xaf0 kernel/hung_task.c:263 #1: (tasklist_lock){.+.+..}, at: [<00000000b10acbed>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4336 2 locks held by getty/2017: #0: (&tty->ldisc_sem){++++++}, at: [<000000009b8f68c9>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376 #1: (&ldata->atomic_read_lock){+.+...}, at: [<00000000062396c5>] n_tty_read+0x1fe/0x1820 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.3/4361: #0: (&sb->s_type->i_mutex_key#8){+.+.+.}, at: [<00000000f20df365>] inode_lock include/linux/fs.h:771 [inline] #0: (&sb->s_type->i_mutex_key#8){+.+.+.}, at: [<00000000f20df365>] __sock_release+0x89/0x2c0 net/socket.c:604 #1: (rtnl_mutex){+.+.+.}, at: [<00000000455b1671>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 2 locks held by kworker/1:3/5326: #0: ("events"){.+.+.+}, at: [<00000000bdd49679>] process_one_work+0x790/0x1600 kernel/workqueue.c:2107 #1: ((&rew.rew_work)){+.+...}, at: [<00000000b0c1f34e>] process_one_work+0x7ce/0x1600 kernel/workqueue.c:2111 5 locks held by kworker/u4:6/10780: #0: ("%s""netns"){.+.+.+}, at: [<00000000bdd49679>] process_one_work+0x790/0x1600 kernel/workqueue.c:2107 #1: (net_cleanup_work){+.+.+.}, at: [<00000000b0c1f34e>] process_one_work+0x7ce/0x1600 kernel/workqueue.c:2111 #2: (net_mutex){+.+.+.}, at: [<000000006bbaf4d9>] cleanup_net+0x131/0x8a0 net/core/net_namespace.c:440 #3: (rtnl_mutex){+.+.+.}, at: [<00000000455b1671>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 #4: (rcu_preempt_state.exp_mutex){+.+...}, at: [<00000000ebe2ccb5>] exp_funnel_lock kernel/rcu/tree_exp.h:256 [inline] #4: (rcu_preempt_state.exp_mutex){+.+...}, at: [<00000000ebe2ccb5>] _synchronize_rcu_expedited+0x339/0x850 kernel/rcu/tree_exp.h:569 3 locks held by kworker/0:2/32087: #0: ("%s"("ipv6_addrconf")){.+.+..}, at: [<00000000bdd49679>] process_one_work+0x790/0x1600 kernel/workqueue.c:2107 #1: ((addr_chk_work).work){+.+...}, at: [<00000000b0c1f34e>] process_one_work+0x7ce/0x1600 kernel/workqueue.c:2111 #2: (rtnl_mutex){+.+.+.}, at: [<00000000455b1671>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 3 locks held by kworker/1:4/5457: #0: ("events"){.+.+.+}, at: [<00000000bdd49679>] process_one_work+0x790/0x1600 kernel/workqueue.c:2107 #1: ((linkwatch_work).work){+.+...}, at: [<00000000b0c1f34e>] process_one_work+0x7ce/0x1600 kernel/workqueue.c:2111 #2: (rtnl_mutex){+.+.+.}, at: [<00000000455b1671>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 1 lock held by syz-executor.5/5487: #0: (rtnl_mutex){+.+.+.}, at: [<00000000a875a557>] rtnl_lock net/core/rtnetlink.c:70 [inline] #0: (rtnl_mutex){+.+.+.}, at: [<00000000a875a557>] rtnetlink_rcv+0x1c/0x40 net/core/rtnetlink.c:4086 1 lock held by syz-executor.3/5495: #0: (rtnl_mutex){+.+.+.}, at: [<00000000455b1671>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 1 lock held by syz-executor.4/5506: #0: (rtnl_mutex){+.+.+.}, at: [<00000000a875a557>] rtnl_lock net/core/rtnetlink.c:70 [inline] #0: (rtnl_mutex){+.+.+.}, at: [<00000000a875a557>] rtnetlink_rcv+0x1c/0x40 net/core/rtnetlink.c:4086 1 lock held by syz-executor.2/5510: #0: (rtnl_mutex){+.+.+.}, at: [<00000000a875a557>] rtnl_lock net/core/rtnetlink.c:70 [inline] #0: (rtnl_mutex){+.+.+.}, at: [<00000000a875a557>] rtnetlink_rcv+0x1c/0x40 net/core/rtnetlink.c:4086 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.194+ #0 ffff8801d98d7cc8 ffffffff81b67001 0000000000000001 0000000000000000 0000000000000001 ffffffff81099d01 dffffc0000000000 ffff8801d98d7d00 ffffffff81b7229c 0000000000000001 0000000000000000 0000000000000001 Call Trace: [<000000004a5390d9>] __dump_stack lib/dump_stack.c:15 [inline] [<000000004a5390d9>] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [<000000007144b47a>] nmi_cpu_backtrace.cold+0x47/0x87 lib/nmi_backtrace.c:99 [<00000000c37b0409>] nmi_trigger_cpumask_backtrace+0x124/0x155 lib/nmi_backtrace.c:60 [<000000008dab917b>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 [<0000000030ec5522>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline] [<0000000030ec5522>] check_hung_task kernel/hung_task.c:126 [inline] [<0000000030ec5522>] check_hung_uninterruptible_tasks kernel/hung_task.c:183 [inline] [<0000000030ec5522>] watchdog+0x670/0xaf0 kernel/hung_task.c:263 [<0000000038473625>] kthread+0x278/0x310 kernel/kthread.c:211 [<00000000c401ffa4>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:375 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1890 Comm: rsyslogd Not tainted 4.9.194+ #0 task: 000000006925569d task.stack: 00000000d604fb74 RIP: 0010:[] c [<00000000c9d45ce2>] __sanitizer_cov_trace_pc+0x26/0x50 kernel/kcov.c:100 RSP: 0018:ffff8801d3d7f638 EFLAGS: 00000246 RAX: ffff8801d417af80 RBX: ffffffff8424df08 RCX: ffff8801d3d7f9d0 RDX: 0000000000000000 RSI: ffffffff81a44425 RDI: ffff8801d3d7f7f6 RBP: ffff8801d3d7f638 R08: 1ffff1003a7aff3a R09: ffff8801d3d7f9d4 R10: ffffed003a7aff3e R11: ffff8801d3d7f9f3 R12: ffffffff8424df08 R13: ffff8801d3d7f990 R14: ffff8801d3d7f7f0 R15: ffff8801d3d7f7f0 FS: 00007fd97f26a700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c42e00b000 CR3: 00000001d5379000 CR4: 00000000001606b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Stack: ffff8801d3d7f6a0c ffffffff81a44425c ffff8801d4d8b300c 070700000000074ec ffff8801d3d7f7f0c ffff8801d4fdacc8c ffff8801d3d7f690c ffffffff81ba475bc ffff8801d4fdacc0c ffffffff8424df08c ffff8801d3d7f990c dffffc0000000000c Call Trace: [<000000009fc55d90>] avtab_search_node+0x65/0x490 security/selinux/ss/avtab.c:225 [<000000000a893d3b>] cond_compute_av+0x58/0x300 security/selinux/ss/conditional.c:646 [<0000000000ecada5>] context_struct_compute_av+0x757/0x1080 security/selinux/ss/services.c:681 [<00000000260acbe2>] security_compute_av+0x290/0x770 security/selinux/ss/services.c:1120 [<000000003f559239>] avc_compute_av+0xc9/0x610 security/selinux/avc.c:974 [<00000000e7eb0d87>] avc_has_perm_noaudit security/selinux/avc.c:1112 [inline] [<00000000e7eb0d87>] avc_has_perm+0x355/0x3a0 security/selinux/avc.c:1146 [<00000000ad3459fe>] task_has_system+0x159/0x230 security/selinux/hooks.c:1703 [<00000000f8b11f0b>] selinux_syslog security/selinux/hooks.c:2259 [inline] [<00000000f8b11f0b>] selinux_syslog+0x35/0xa0 security/selinux/hooks.c:2238 [<00000000ad2023b6>] security_syslog+0x73/0xb0 security/security.c:210 [<0000000072ae1290>] check_syslog_permissions+0x5b/0xb0 kernel/printk/printk.c:635 [<00000000755f72f3>] do_syslog+0x9b/0xaf0 kernel/printk/printk.c:1440 [<000000007a4301d4>] kmsg_read+0x74/0xa0 fs/proc/kmsg.c:39 [<000000001bc77155>] proc_reg_read+0xfd/0x180 fs/proc/inode.c:203 [<0000000078885a9e>] __vfs_read+0x116/0x550 fs/read_write.c:451 [<000000002e037b7c>] vfs_read+0x137/0x380 fs/read_write.c:474 [<000000003d5cff31>] SYSC_read fs/read_write.c:591 [inline] [<000000003d5cff31>] SyS_read+0x121/0x270 fs/read_write.c:584 [<00000000b04a243b>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288 [<0000000052f2366f>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Code: c00 c0f c1f c40 c00 c55 c48 c89 ce5 c48 c8b c75 c08 c65 c48 c8b c04 c25 c00 c7e c01 c00 c65 c8b c15 c78 c56 ccf c7e c81 ce2 c00 c01 c1f c00 c75 c2b c8b c90 c38 c12 c00 c00 c<83> cfa c02 c75 c20 c48 c8b c88 c40 c12 c00 c00 c8b c80 c3c c12 c00 c00 c48 c8b c11 c