audit: type=1400 audit(1564364895.864:2556): avc: denied { write } for pid=29675 comm="syz-executor.5" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=netlink_generic_socket permissive=1 INFO: task syz-executor.3:27099 blocked for more than 140 seconds. Not tainted 4.9.186+ #10 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D25512 27099 1 0x00000004 0000000000000087 ffff8801a8774740 ffff8801ae662680 ffff8801db621000 ffff8801a4920000 ffff8801db621018 ffff8801af65f4c8 ffffffff8280c5ee ffffffff81bc08fc ffff8801af65f4f8 00ffffff81203c2e ffff8801db6218f0 Call Trace: [<00000000751663e6>] schedule+0x92/0x1c0 kernel/sched/core.c:3546 [<0000000092c25c8b>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3579 [<000000007c88090e>] __mutex_lock_common kernel/locking/mutex.c:582 [inline] [<000000007c88090e>] mutex_lock_nested+0x38d/0x920 kernel/locking/mutex.c:621 [<00000000e1c24ad2>] fuse_lock_inode+0xad/0xe0 fs/fuse/inode.c:364 [<00000000fe4950fb>] fuse_lookup+0x89/0x3b0 fs/fuse/dir.c:406 [<00000000046c6f76>] lookup_slow+0x24b/0x480 fs/namei.c:1709 [<00000000145685fa>] walk_component+0x71e/0xce0 fs/namei.c:1825 [<000000000a1ec6ce>] link_path_walk+0x897/0x1200 fs/namei.c:2161 [<00000000275b4301>] path_openat+0x18e/0x2f60 fs/namei.c:3580 [<00000000dd3579d3>] do_filp_open+0x1a1/0x280 fs/namei.c:3615 [<00000000ae757d3b>] do_sys_open+0x2f0/0x610 fs/open.c:1078 [<000000000a93476b>] SYSC_open fs/open.c:1096 [inline] [<000000000a93476b>] SyS_open+0x2d/0x40 fs/open.c:1091 [<0000000036d85c69>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288 [<00000000c5990c92>] 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: [<00000000c11592c8>] check_hung_uninterruptible_tasks kernel/hung_task.c:169 [inline] #0: (rcu_read_lock){......}, at: [<00000000c11592c8>] watchdog+0x14b/0xaf0 kernel/hung_task.c:263 #1: (tasklist_lock){.+.+..}, at: [<00000000f70cd99f>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4336 2 locks held by rs:main Q:Reg/1907: #0: (&f->f_pos_lock){+.+.+.}, at: [<0000000076c0acd6>] __fdget_pos+0xa8/0xd0 fs/file.c:782 #1: (sb_writers#4){.+.+.+}, at: [<00000000dc131e79>] file_start_write include/linux/fs.h:2646 [inline] #1: (sb_writers#4){.+.+.+}, at: [<00000000dc131e79>] vfs_write+0x3e9/0x520 fs/read_write.c:558 2 locks held by getty/2038: #0: (&tty->ldisc_sem){++++++}, at: [<000000008bdf607e>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377 #1: (&ldata->atomic_read_lock){+.+.+.}, at: [<00000000f8fdc158>] n_tty_read+0x1fe/0x1820 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.3/27099: #0: (&type->i_mutex_dir_key#7){++++++}, at: [<0000000015db8cdf>] inode_lock_shared include/linux/fs.h:781 [inline] #0: (&type->i_mutex_dir_key#7){++++++}, at: [<0000000015db8cdf>] lookup_slow+0x160/0x480 fs/namei.c:1686 #1: (&fi->mutex){+.+.+.}, at: [<00000000e1c24ad2>] fuse_lock_inode+0xad/0xe0 fs/fuse/inode.c:364 2 locks held by syz-executor.3/29635: #0: (&type->i_mutex_dir_key#7){++++++}, at: [<0000000015db8cdf>] inode_lock_shared include/linux/fs.h:781 [inline] #0: (&type->i_mutex_dir_key#7){++++++}, at: [<0000000015db8cdf>] lookup_slow+0x160/0x480 fs/namei.c:1686 #1: (&fi->mutex){+.+.+.}, at: [<00000000e1c24ad2>] fuse_lock_inode+0xad/0xe0 fs/fuse/inode.c:364 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 24 Comm: khungtaskd Not tainted 4.9.186+ #10 ffff8801d98d7cc8 ffffffff81b5a0b1 0000000000000000 0000000000000000 0000000000000000 ffffffff81099a01 dffffc0000000000 ffff8801d98d7d00 ffffffff81b6534c 0000000000000000 0000000000000000 0000000000000000 Call Trace: [<00000000df924316>] __dump_stack lib/dump_stack.c:15 [inline] [<00000000df924316>] dump_stack+0xc1/0x120 lib/dump_stack.c:51 [<000000000bbd64ab>] nmi_cpu_backtrace.cold+0x47/0x87 lib/nmi_backtrace.c:99 [<00000000eaa0dc7d>] nmi_trigger_cpumask_backtrace+0x124/0x155 lib/nmi_backtrace.c:60 [<00000000aa549ead>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37 [<0000000007513fee>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline] [<0000000007513fee>] check_hung_task kernel/hung_task.c:126 [inline] [<0000000007513fee>] check_hung_uninterruptible_tasks kernel/hung_task.c:183 [inline] [<0000000007513fee>] watchdog+0x670/0xaf0 kernel/hung_task.c:263 [<00000000922b6547>] kthread+0x278/0x310 kernel/kthread.c:211 [<000000006bf61f70>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:375 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 29646 Comm: syz-executor.3 Not tainted 4.9.186+ #10 task: 0000000087624974 task.stack: 00000000eb7e6ba1 RIP: 0010:[] c [<000000002b1a667b>] mark_held_locks+0xa5/0x100 kernel/locking/lockdep.c:2657 RSP: 0018:ffff8801c50c7200 EFLAGS: 00000002 RAX: 0000000000000005 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: ffff8801c83367b0 RDI: ffff8801c83367d2 RBP: ffff8801c50c7238 R08: 0000000000000282 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801c83367b0 R13: 0000000000000002 R14: ffff8801c8335f00 R15: dffffc0000000000 FS: 00007f8e902dd700(0000) GS:ffff8801db700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1087112280 CR3: 00000001cfffe000 CR4: 00000000001606b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffffff811f2f8fc 00000003c83367a8c ffff8801c8335f00c ffffffff8281c2bac 1ffff10038a18e58c fffffffffffffe00c ffff8801c50c73a8c ffff8801c50c7258c ffffffff8120b4a0c 0000000000000282c ffff8801d6a147a8c ffff8801c50c7268c Call Trace: [<00000000b420f2c7>] __trace_hardirqs_on_caller kernel/locking/lockdep.c:2681 [inline] [<00000000b420f2c7>] trace_hardirqs_on_caller+0x260/0x5a0 kernel/locking/lockdep.c:2736 [<000000008291b02c>] trace_hardirqs_on+0xd/0x10 kernel/locking/lockdep.c:2743 [<0000000006f5bccc>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:162 [inline] [<0000000006f5bccc>] _raw_spin_unlock_irqrestore+0x5a/0x70 kernel/locking/spinlock.c:191 [<000000005a5095d7>] spin_unlock_irqrestore include/linux/spinlock.h:362 [inline] [<000000005a5095d7>] prepare_to_wait_event+0x128/0x750 kernel/sched/wait.c:238 [<000000008940e0e0>] request_wait_answer+0x249/0x820 fs/fuse/dev.c:477 [<00000000251f9b21>] __fuse_request_send+0x109/0x1b0 fs/fuse/dev.c:498 [<0000000006cf225c>] fuse_request_send+0x63/0x70 fs/fuse/dev.c:511 [<00000000a2782951>] fuse_simple_request+0x2c4/0x660 fs/fuse/dev.c:569 [<00000000f242976e>] fuse_lookup_name+0x260/0x640 fs/fuse/dir.c:369 [<0000000005aeb696>] fuse_lookup+0xec/0x3b0 fs/fuse/dir.c:407 [<00000000046c6f76>] lookup_slow+0x24b/0x480 fs/namei.c:1709 [<00000000145685fa>] walk_component+0x71e/0xce0 fs/namei.c:1825 [<000000000a1ec6ce>] link_path_walk+0x897/0x1200 fs/namei.c:2161 [<00000000275b4301>] path_openat+0x18e/0x2f60 fs/namei.c:3580 [<000000003e588e5d>] do_filp_open+0x219/0x280 fs/namei.c:3617 [<00000000ae757d3b>] do_sys_open+0x2f0/0x610 fs/open.c:1078 [<00000000a90a7dd7>] SYSC_openat fs/open.c:1105 [inline] [<00000000a90a7dd7>] SyS_openat+0x30/0x40 fs/open.c:1099 [<0000000036d85c69>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288 [<00000000c5990c92>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb Code: c48 c8d c7e c22 c48 c89 cf8 c48 c89 cfa c48 cc1 ce8 c03 c83 ce2 c07 c42 c0f cb6 c04 c38 c38 cd0 c7f c04 c84 cc0 c75 c4d c0f cb6 c46 c22 c8b c55 cd4 ca8 c03 c41 c0f c44 cd5 c c04 c74 c0c c4c c89 cf7 ce8 c6f cec cff cff c85 cc0 c74 c11 c83 cc3 c01 c41 c39 c