overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection. INFO: task syz-executor.1:6406 blocked for more than 140 seconds. Not tainted 4.19.129-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D27856 6406 6588 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x8a2/0x1fc0 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x8f3/0xed0 kernel/time/timer.c:1782 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x192/0x2b0 kernel/locking/semaphore.c:238 down+0x57/0x80 kernel/locking/semaphore.c:62 console_lock+0x25/0x80 kernel/printk/printk.c:2244 vcs_open+0x62/0xc0 drivers/tty/vt/vc_screen.c:660 chrdev_open+0x219/0x5c0 fs/char_dev.c:423 do_dentry_open+0x4a8/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0xe06/0x2eb0 fs/namei.c:3537 do_filp_open+0x1a1/0x280 fs/namei.c:3567 do_sys_open+0x3aa/0x510 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x416851 Code: d8 b9 28 00 00 00 e8 6e 10 05 00 48 89 d8 b9 28 00 00 00 e8 61 10 05 00 48 89 d8 b9 28 00 00 00 e8 54 10 05 00 48 89 d8 b9 28 <00> 00 00 e8 47 10 05 00 48 89 d8 b9 28 00 00 00 e8 3a 10 05 00 48 RSP: 002b:00007f1c1d0787a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000416851 RDX: 0000000000000000 RSI: 00000000001e3942 RDI: 00007f1c1d078850 RBP: 000000000078bf00 R08: 000000000000000f R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000293 R12: 00000000ffffffff R13: 0000000000000c44 R14: 00000000004ce9bb R15: 00007f1c1d0796d4 INFO: task syz-executor.1:6442 blocked for more than 140 seconds. Not tainted 4.19.129-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28016 6442 6588 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x8a2/0x1fc0 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x8f3/0xed0 kernel/time/timer.c:1782 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x192/0x2b0 kernel/locking/semaphore.c:238 down+0x57/0x80 kernel/locking/semaphore.c:62 console_lock+0x25/0x80 kernel/printk/printk.c:2244 vcs_open+0x62/0xc0 drivers/tty/vt/vc_screen.c:660 chrdev_open+0x219/0x5c0 fs/char_dev.c:423 do_dentry_open+0x4a8/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0xe06/0x2eb0 fs/namei.c:3537 do_filp_open+0x1a1/0x280 fs/namei.c:3567 do_sys_open+0x3aa/0x510 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x416851 Code: d8 b9 28 00 00 00 e8 6e 10 05 00 48 89 d8 b9 28 00 00 00 e8 61 10 05 00 48 89 d8 b9 28 00 00 00 e8 54 10 05 00 48 89 d8 b9 28 <00> 00 00 e8 47 10 05 00 48 89 d8 b9 28 00 00 00 e8 3a 10 05 00 48 RSP: 002b:00007f1c1d0367a0 EFLAGS: 00000293 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 6666666666666667 RCX: 0000000000416851 RDX: 0000000000000000 RSI: 00000000001e3942 RDI: 00007f1c1d036850 RBP: 000000000078c040 R08: 000000000000000f R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00000000ffffffff R13: 0000000000000c44 R14: 00000000004ce9bb R15: 00007f1c1d0376d4 Showing all locks held in the system: 1 lock held by khungtaskd/1079: #0: 000000004374785a (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440 1 lock held by in:imklog/6151: #0: 0000000058600630 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:767 2 locks held by agetty/6378: #0: 00000000d556d7af (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000a94557e5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by agetty/6379: #0: 00000000dc46fc82 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 000000000960620a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 1 lock held by syz-executor.3/6405: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1079 Comm: khungtaskd Not tainted 4.19.129-syzkaller #0 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+0x1fc/0x2fe lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x962/0xe40 kernel/hung_task.c:287 kthread+0x30b/0x410 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6405 Comm: syz-executor.3 Not tainted 4.19.129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:check_kcov_mode kernel/kcov.c:67 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x14/0x50 kernel/kcov.c:101 Code: e8 d0 91 eb ff 48 c7 05 66 57 08 0a 00 00 00 00 e9 24 ec ff ff 90 48 8b 34 24 65 48 8b 04 25 40 ee 01 00 65 8b 15 dc e7 99 7e <81> e2 00 01 1f 00 75 2b 8b 90 d8 12 00 00 83 fa 02 75 20 48 8b 88 RSP: 0018:ffff8880549df740 EFLAGS: 00000212 RAX: ffff88805603e280 RBX: 0000000000000050 RCX: ffffffff837ccaaa RDX: 0000000080000000 RSI: ffffffff837cca96 RDI: 0000000000000004 RBP: 000000000000003b R08: ffff88805603e280 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880000a003b R13: ffff8880000a0000 R14: 0000000000000000 R15: 00000000ef040a72 FS: 00007f91c05f2700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c0009ed020 CR3: 0000000049458000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: writeb arch/x86/include/asm/io.h:65 [inline] vga16fb_fillrect+0x9c6/0x1960 drivers/video/fbdev/vga16fb.c:923 bit_clear_margins+0x2d5/0x4a0 drivers/video/fbdev/core/bitblit.c:232 fbcon_clear_margins+0x2c7/0x350 drivers/video/fbdev/core/fbcon.c:1342 fbcon_do_set_font+0x71d/0xa30 drivers/video/fbdev/core/fbcon.c:2585 fbcon_set_font+0x72c/0x860 drivers/video/fbdev/core/fbcon.c:2677 con_font_set drivers/tty/vt/vt.c:4529 [inline] con_font_op+0xd3e/0x1130 drivers/tty/vt/vt.c:4594 vt_ioctl+0xb88/0x24a0 drivers/tty/vt/vt_ioctl.c:928 tty_ioctl+0x7a5/0x1420 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcda/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45ca59 Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f91c05f1c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004ef2e0 RCX: 000000000045ca59 RDX: 0000000020000000 RSI: 0000000000004b61 RDI: 0000000000000003 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000581 R14: 00000000004c839c R15: 00007f91c05f26d4