audit: type=1400 audit(1565481249.431:12070): avc: denied { setopt } for pid=9837 comm="syz-executor.3" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_netfilter_socket permissive=1 INFO: task syz-executor.1:2107 blocked for more than 140 seconds. Not tainted 4.9.188+ #19 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D24904 2107 1 0x00000004 0000000000000083 ffff8801d0838000 ffff8801d47d9b80 ffff8801db621000 ffff8801d293af80 ffff8801db621018 ffff8801a82177a0 ffffffff8281749e ffff8801d083887c ffff8801a82177a0 00ffffff828283e6 ffff8801db6218f0 Call Trace: [<000000003699d413>] schedule+0x92/0x1c0 kernel/sched/core.c:3546 [<000000008a0c2703>] schedule_timeout+0x766/0xe50 kernel/time/timer.c:1771 [<00000000444da438>] io_schedule_timeout+0x1ba/0x390 kernel/sched/core.c:5171 [<0000000044be09b7>] io_schedule include/linux/sched.h:432 [inline] [<0000000044be09b7>] wait_on_page_bit_common mm/filemap.c:910 [inline] [<0000000044be09b7>] wait_on_page_bit+0x34c/0x660 mm/filemap.c:949 [<00000000cf335ced>] wait_on_page_writeback include/linux/pagemap.h:534 [inline] [<00000000cf335ced>] truncate_inode_pages_range+0x6fc/0xfe0 mm/truncate.c:375 [<00000000f019a8fb>] truncate_inode_pages mm/truncate.c:401 [inline] [<00000000f019a8fb>] truncate_inode_pages_final+0x81/0xc0 mm/truncate.c:452 [<00000000534429ed>] ext4_evict_inode+0x3e2/0x1270 fs/ext4/inode.c:234 [<00000000cce793fd>] evict+0x2e9/0x630 fs/inode.c:553 [<00000000388f65bc>] iput_final fs/inode.c:1516 [inline] [<00000000388f65bc>] iput fs/inode.c:1543 [inline] [<00000000388f65bc>] iput+0x370/0x900 fs/inode.c:1528 [<00000000362434ae>] do_unlinkat+0x395/0x610 fs/namei.c:4134 [<000000009c228155>] SYSC_unlink fs/namei.c:4175 [inline] [<000000009c228155>] SyS_unlink+0x1b/0x20 fs/namei.c:4173 [<000000009c0c48fa>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288 [<000000004a598f78>] 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: [<000000002a9f3c3f>] check_hung_uninterruptible_tasks kernel/hung_task.c:169 [inline] #0: (rcu_read_lock){......}, at: [<000000002a9f3c3f>] watchdog+0x14b/0xaf0 kernel/hung_task.c:263 #1: (tasklist_lock){.+.+..}, at: [<00000000163ba423>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4336 2 locks held by getty/2037: #0: (&tty->ldisc_sem){++++++}, at: [<00000000d97795ec>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+...}, at: [<000000006fdc51f9>] n_tty_read+0x1fe/0x1820 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.1/2107: #0: (sb_writers#4){.+.+.+}, at: [<000000003fbc84ff>] sb_start_write include/linux/fs.h:1579 [inline] #0: (sb_writers#4){.+.+.+}, at: [<000000003fbc84ff>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391 3 locks held by kworker/u4:13/366: #0: ("writeback"){++++.+}, at: [<000000008e1feb20>] process_one_work+0x790/0x1600 kernel/workqueue.c:2107 #1: ((&(&wb->dwork)->work)){+.+.+.}, at: [<0000000042c39c3e>] process_one_work+0x7ce/0x1600 kernel/workqueue.c:2111 #2: (&type->s_umount_key#22){++++..}, at: [<00000000d11469df>] trylock_super+0x20/0xf0 fs/super.c:403 2 locks held by syz-executor.2/5929: #0: (sb_writers#4){.+.+.+}, at: [<0000000027573b8e>] file_start_write include/linux/fs.h:2646 [inline] #0: (sb_writers#4){.+.+.+}, at: [<0000000027573b8e>] do_sendfile+0x93a/0xc00 fs/read_write.c:1401 #1: (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [<000000004128f99e>] inode_lock include/linux/fs.h:771 [inline] #1: (&sb->s_type->i_mutex_key#9){+.+.+.}, at: [<000000004128f99e>] ext4_file_write_iter+0x111/0xcd0 fs/ext4/file.c:100 1 lock held by syz-executor.2/5952: #0: (sb_writers#4){.+.+.+}, at: [<0000000027573b8e>] file_start_write include/linux/fs.h:2646 [inline] #0: (sb_writers#4){.+.+.+}, at: [<0000000027573b8e>] do_sendfile+0x93a/0xc00 fs/read_write.c:1401 1 lock held by syz-executor.3/9837: #0: (&sbi->s_journal_flag_rwsem){.+.+.+}, at: [<00000000a62a8c27>] do_writepages+0xfc/0x1e0 mm/page-writeback.c:2338 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.188+ #19 ffff8801d98d7cc8 ffffffff81b64a21 0000000000000001 0000000000000000 0000000000000001 ffffffff81099a01 dffffc0000000000 ffff8801d98d7d00 ffffffff81b6fcbc 0000000000000001 0000000000000000 0000000000000001 Call Trace: [<00000000d61bfc93>] __dump_stack lib/dump_stack.c:15 [inline] [<00000000d61bfc93>] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [<00000000c460d456>] nmi_cpu_backtrace.cold+0x47/0x87 lib/nmi_backtrace.c:99 [<0000000016895227>] nmi_trigger_cpumask_backtrace+0x124/0x155 lib/nmi_backtrace.c:60 [<00000000e1f8903e>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 [<00000000645787b3>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline] [<00000000645787b3>] check_hung_task kernel/hung_task.c:126 [inline] [<00000000645787b3>] check_hung_uninterruptible_tasks kernel/hung_task.c:183 [inline] [<00000000645787b3>] watchdog+0x670/0xaf0 kernel/hung_task.c:263 [<00000000c3a63bac>] kthread+0x278/0x310 kernel/kthread.c:211 [<0000000036bff467>] 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 skipped: idling at pc 0xffffffff828265f1