audit: type=1400 audit(1521878105.936:82274): avc: denied { map } for pid=27732 comm="blkid" path="/lib/x86_64-linux-gnu/libuuid.so.1.3.0" dev="sda1" ino=2819 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 bond0 (unregistering): Released all slaves Buffer I/O error on dev loop0, logical block 3, async page read INFO: task syz-executor2:27677 blocked for more than 120 seconds. Not tainted 4.16.0-rc6+ #364 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor2 D26288 27677 4289 0x00000004 Call Trace: context_switch kernel/sched/core.c:2862 [inline] __schedule+0x8fb/0x1ec0 kernel/sched/core.c:3440 schedule+0xf5/0x430 kernel/sched/core.c:3499 io_schedule+0x1c/0x70 kernel/sched/core.c:5115 wait_on_page_bit_common+0x4b3/0x770 mm/filemap.c:1099 wait_on_page_bit mm/filemap.c:1132 [inline] wait_on_page_writeback include/linux/pagemap.h:546 [inline] __filemap_fdatawait_range+0x282/0x430 mm/filemap.c:533 file_write_and_wait_range+0xd7/0x100 mm/filemap.c:756 blkdev_fsync+0x67/0xb0 fs/block_dev.c:623 vfs_fsync_range+0x110/0x260 fs/sync.c:196 vfs_fsync fs/sync.c:210 [inline] do_fsync+0x42/0x70 fs/sync.c:220 SYSC_fsync fs/sync.c:228 [inline] SyS_fsync+0x16/0x20 fs/sync.c:226 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x454239 RSP: 002b:00007f1d176c9c68 EFLAGS: 00000246 ORIG_RAX: 000000000000004a RAX: ffffffffffffffda RBX: 00007f1d176ca6d4 RCX: 0000000000454239 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000000a0 R14: 00000000006f1fa0 R15: 0000000000000000 Showing all locks held in the system: 3 locks held by kworker/u4:2/56: #0: ((wq_completion)"writeback"){+.+.}, at: [<00000000e307b97d>] work_static include/linux/workqueue.h:198 [inline] #0: ((wq_completion)"writeback"){+.+.}, at: [<00000000e307b97d>] set_work_data kernel/workqueue.c:619 [inline] #0: ((wq_completion)"writeback"){+.+.}, at: [<00000000e307b97d>] set_work_pool_and_clear_pending kernel/workqueue.c:646 [inline] #0: ((wq_completion)"writeback"){+.+.}, at: [<00000000e307b97d>] process_one_work+0xb12/0x1bb0 kernel/workqueue.c:2084 #1: ((work_completion)(&(&wb->dwork)->work)){+.+.}, at: [<000000004a81848a>] process_one_work+0xb89/0x1bb0 kernel/workqueue.c:2088 #2: (&type->s_umount_key#27){.+.+}, at: [<0000000040c57dbb>] trylock_super+0x20/0x100 fs/super.c:395 2 locks held by khungtaskd/800: #0: (rcu_read_lock){....}, at: [<000000000bd99f2e>] check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: (rcu_read_lock){....}, at: [<000000000bd99f2e>] watchdog+0x1c5/0xd60 kernel/hung_task.c:249 #1: (tasklist_lock){.+.+}, at: [<00000000103c9533>] debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470 2 locks held by getty/4207: #0: (&tty->ldisc_sem){++++}, at: [<0000000080e15463>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000d6fa9db8>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4208: #0: (&tty->ldisc_sem){++++}, at: [<0000000080e15463>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000d6fa9db8>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4209: #0: (&tty->ldisc_sem){++++}, at: [<0000000080e15463>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000d6fa9db8>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4210: #0: (&tty->ldisc_sem){++++}, at: [<0000000080e15463>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000d6fa9db8>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4211: #0: (&tty->ldisc_sem){++++}, at: [<0000000080e15463>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000d6fa9db8>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4212: #0: (&tty->ldisc_sem){++++}, at: [<0000000080e15463>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000d6fa9db8>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 2 locks held by getty/4213: #0: (&tty->ldisc_sem){++++}, at: [<0000000080e15463>] ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: (&ldata->atomic_read_lock){+.+.}, at: [<00000000d6fa9db8>] n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 800 Comm: khungtaskd Not tainted 4.16.0-rc6+ #364 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+0x194/0x24d lib/dump_stack.c:53 nmi_cpu_backtrace+0x1d2/0x210 lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x123/0x180 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:138 [inline] check_hung_task kernel/hung_task.c:132 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] watchdog+0x90c/0xd60 kernel/hung_task.c:249 kthread+0x33c/0x400 kernel/kthread.c:238 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:406 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4085 Comm: rsyslogd Not tainted 4.16.0-rc6+ #364 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rcu_is_watching+0x45/0x110 kernel/rcu/tree.c:1071 RSP: 0018:ffff8801b648f638 EFLAGS: 00000092 RAX: ffffed0036c91ec8 RBX: 1ffff10036c91ec8 RCX: ffffffff8220faa2 RDX: dffffc0000000000 RSI: 00000000069e9271 RDI: ffff8801b68c8b74 RBP: ffff8801b648f6b8 R08: 1ffff10036c91e1b R09: 000000000000000a R10: ffff8801b648f598 R11: 0000000000000000 R12: ffffffff886037b0 R13: ffff8801b648f6a0 R14: dffffc0000000000 R15: ffffffff86ec9ce0 FS: 00007fbdfee2a700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001b6b53004 CR4: 00000000001606f0 DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: rcu_read_lock include/linux/rcupdate.h:631 [inline] avc_reclaim_node security/selinux/avc.c:527 [inline] avc_alloc_node+0x427/0x4d0 security/selinux/avc.c:557 avc_insert security/selinux/avc.c:668 [inline] avc_compute_av+0x22a/0x710 security/selinux/avc.c:974 avc_has_perm_noaudit security/selinux/avc.c:1110 [inline] avc_has_perm+0x4be/0x680 security/selinux/avc.c:1144 selinux_syslog+0x239/0x2a0 security/selinux/hooks.c:2293 security_syslog+0x6d/0xa0 security/security.c:299 check_syslog_permissions+0x59/0x100 kernel/printk/printk.c:682 do_syslog+0x82/0xb80 kernel/printk/printk.c:1439 kmsg_read+0x74/0xa0 fs/proc/kmsg.c:40 proc_reg_read+0xe8/0x160 fs/proc/inode.c:218 __vfs_read+0xef/0xa00 fs/read_write.c:411 vfs_read+0x11e/0x350 fs/read_write.c:447 SYSC_read fs/read_write.c:573 [inline] SyS_read+0xef/0x220 fs/read_write.c:566 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x7fbe0188a1fd RSP: 002b:00007fbdfee29e30 EFLAGS: 00000293 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 0000000001d504b0 RCX: 00007fbe0188a1fd RDX: 0000000000000fff RSI: 00007fbe0065e5a0 RDI: 0000000000000004 RBP: 0000000000000000 R08: 0000000001d3b260 R09: 0000000004000001 R10: 0000000000000001 R11: 0000000000000293 R12: 000000000065e420 R13: 00007fbdfee2a9c0 R14: 00007fbe01ecf040 R15: 0000000000000003 Code: e8 48 c1 eb 03 48 83 ec 68 48 c7 45 88 b3 8a b5 41 48 8d 04 13 48 c7 45 90 c2 89 c3 86 48 c7 45 98 d0 dc 5d 81 c7 00 f1 f1 f1 f1 40 04 04 f2 f2 f2 c7 40 08 f3 f3 f3 f3 65 ff 05 26 10 a4 7e