cgroup: fork rejected by pids controller in /syz3 INFO: task syz-executor3:24464 blocked for more than 140 seconds. Not tainted 4.19.0-rc7+ #60 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D23128 24464 5440 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 fanotify_get_response fs/notify/fanotify/fanotify.c:68 [inline] fanotify_handle_event+0x7fb/0x9a0 fs/notify/fanotify/fanotify.c:245 send_to_group fs/notify/fsnotify.c:234 [inline] fsnotify+0x87f/0x12f0 fs/notify/fsnotify.c:367 fsnotify_perm include/linux/fsnotify.h:52 [inline] security_file_open+0x16f/0x1b0 security/security.c:986 do_dentry_open+0x331/0x1250 fs/open.c:758 vfs_open+0xa0/0xd0 fs/open.c:880 do_last fs/namei.c:3418 [inline] path_openat+0x12bf/0x5160 fs/namei.c:3534 do_filp_open+0x255/0x380 fs/namei.c:3564 do_sys_open+0x568/0x700 fs/open.c:1063 ksys_open include/linux/syscalls.h:1276 [inline] __do_sys_creat fs/open.c:1121 [inline] __se_sys_creat fs/open.c:1119 [inline] __x64_sys_creat+0x61/0x80 fs/open.c:1119 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: Bad RIP value. RSP: 002b:00007f04f8e2cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000380 RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f04f8e2d6d4 R13: 00000000004bdb2f R14: 00000000004cc688 R15: 00000000ffffffff INFO: task syz-executor3:24496 blocked for more than 140 seconds. Not tainted 4.19.0-rc7+ #60 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D25352 24496 5440 0x00000004 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 fanotify_get_response fs/notify/fanotify/fanotify.c:68 [inline] fanotify_handle_event+0x7fb/0x9a0 fs/notify/fanotify/fanotify.c:245 send_to_group fs/notify/fsnotify.c:234 [inline] fsnotify+0x87f/0x12f0 fs/notify/fsnotify.c:367 fsnotify_perm include/linux/fsnotify.h:52 [inline] security_file_open+0x16f/0x1b0 security/security.c:986 do_dentry_open+0x331/0x1250 fs/open.c:758 vfs_open+0xa0/0xd0 fs/open.c:880 do_last fs/namei.c:3418 [inline] path_openat+0x12bf/0x5160 fs/namei.c:3534 do_filp_open+0x255/0x380 fs/namei.c:3564 do_sys_open+0x568/0x700 fs/open.c:1063 __do_sys_openat fs/open.c:1090 [inline] __se_sys_openat fs/open.c:1084 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1084 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: Bad RIP value. RSP: 002b:00007f04f8e0bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569 RDX: 0000000000000000 RSI: 0000000020000140 RDI: ffffffffffffff9c RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f04f8e0c6d4 R13: 00000000004c2b6b R14: 00000000004d41b8 R15: 00000000ffffffff Showing all locks held in the system: 1 lock held by khungtaskd/983: #0: 00000000fdc3aa7c (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4435 1 lock held by rsyslogd/5245: #0: 000000001aecf354 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766 2 locks held by getty/5335: #0: 000000001a352e6b (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000b1b17864 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5336: #0: 0000000060243900 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000fc1d0b03 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5337: #0: 00000000ce1ca66d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000acebc723 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5338: #0: 00000000952c904f (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 0000000059e412a8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5339: #0: 00000000b808a9f3 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000ca973477 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5340: #0: 00000000f7e06d48 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 000000000316f75e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 2 locks held by getty/5341: #0: 000000003f0dcaed (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353 #1: 00000000417dfe62 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1ce0 drivers/tty/n_tty.c:2140 1 lock held by syz-executor3/24464: #0: 00000000eab704ad (sb_writers#3){.+.+}, at: sb_start_write include/linux/fs.h:1566 [inline] #0: 00000000eab704ad (sb_writers#3){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:360 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 983 Comm: khungtaskd Not tainted 4.19.0-rc7+ #60 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed 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:144 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline] watchdog+0xb3e/0x1050 kernel/hung_task.c:265 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57