base_sock_release(00000000528b61ac) sk=000000003caa62eb caif:caif_disconnect_client(): nothing to disconnect caif:caif_disconnect_client(): nothing to disconnect caif:caif_disconnect_client(): nothing to disconnect caif:caif_disconnect_client(): nothing to disconnect INFO: task syz-executor.4:27534 blocked for more than 140 seconds. Not tainted 4.19.121-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D26880 27534 6794 0x80000002 Call Trace: schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x896/0xf20 kernel/time/timer.c:1782 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x176/0x2c0 kernel/locking/semaphore.c:238 down+0x57/0x80 kernel/locking/semaphore.c:62 console_lock+0x25/0x80 kernel/printk/printk.c:2244 con_shutdown+0x3d/0x90 drivers/tty/vt/vt.c:3276 release_tty+0xda/0x4c0 drivers/tty/tty_io.c:1509 tty_release_struct+0x37/0x50 drivers/tty/tty_io.c:1624 tty_release+0xbc7/0xe90 drivers/tty/tty_io.c:1784 __fput+0x2cd/0x890 fs/file_table.c:278 task_work_run+0x13f/0x1b0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0xbcd/0x2f30 kernel/exit.c:880 do_group_exit+0x125/0x350 kernel/exit.c:983 get_signal+0x3ec/0x1f90 kernel/signal.c:2588 do_signal+0x8f/0x1710 arch/x86/kernel/signal.c:821 exit_to_usermode_loop+0x22b/0x2b0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c829 Code: 08 48 c7 44 24 10 09 00 00 00 e8 02 a1 fa ff 48 8b 44 24 18 48 8b 4c 24 30 48 83 c1 10 48 89 0c 24 48 89 44 24 08 48 c7 44 24 <10> 58 1f 00 00 e8 dd a0 fa ff 48 8b 44 24 18 48 89 44 24 40 48 8b RSP: 002b:00007f8c69d31cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000078bf08 RCX: 000000000045c829 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000078bf08 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c R13: 00007fff27d16f8f R14: 00007f8c69d329c0 R15: 000000000078bf0c Showing all locks held in the system: 1 lock held by khungtaskd/1075: #0: 000000005870d5f1 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440 1 lock held by in:imklog/6106: #0: 00000000e39585ad (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xe3/0x100 fs/file.c:767 2 locks held by agetty/6141: #0: 000000006de8fdda (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000cb8d1b18 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 2 locks held by agetty/6142: #0: 00000000bbad67a7 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000d0b7479f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1a50 drivers/tty/n_tty.c:2154 1 lock held by syz-executor.4/27534: #0: 000000001e77ce4b (tty_mutex){+.+.}, at: tty_release_struct+0x2c/0x50 drivers/tty/tty_io.c:1623 1 lock held by syz-executor.4/29275: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1075 Comm: khungtaskd Not tainted 4.19.121-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+0x188/0x20d 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+0x34a/0x420 kernel/kthread.c:246 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 29275 Comm: syz-executor.4 Not tainted 4.19.121-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_cmp4+0x4/0x20 kernel/kcov.c:162 Code: b6 f7 31 ff eb 80 48 8b 0c 24 0f b7 d6 0f b7 f7 bf 02 00 00 00 e9 6c ff ff ff 66 90 66 2e 0f 1f 84 00 00 00 00 00 48 8b 0c 24 <89> f2 89 fe bf 04 00 00 00 e9 4e ff ff ff 0f 1f 40 00 66 2e 0f 1f RSP: 0018:ffff888212f574f8 EFLAGS: 00000286 RAX: 0000000000040000 RBX: 0000000000000050 RCX: ffffffff837b76ea RDX: 0000000000040000 RSI: 0000000000000014 RDI: 0000000000000050 RBP: 0000000000000014 R08: ffff88808cc5c640 R09: ffffed1014bbcbe4 R10: ffffed1014bbcbe3 R11: ffff8880a5de5f1f R12: ffff8880000a0014 R13: ffff8880000a0000 R14: 0000000000000000 R15: 00000000e7bd3887 FS: 00007f8c69d11700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f66496cd000 CR3: 000000008268e000 CR4: 00000000001426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vga16fb_fillrect+0x9da/0x1960 drivers/video/fbdev/vga16fb.c:922 bit_clear_margins+0x2d5/0x4a0 drivers/video/fbdev/core/bitblit.c:232 fbcon_clear_margins+0x2d8/0x370 drivers/video/fbdev/core/fbcon.c:1342 fbcon_switch+0xe0f/0x1970 drivers/video/fbdev/core/fbcon.c:2324 redraw_screen+0x37d/0x870 drivers/tty/vt/vt.c:1010 fbcon_do_set_font+0x727/0xa30 drivers/video/fbdev/core/fbcon.c:2586 fbcon_set_font+0x733/0x870 drivers/video/fbdev/core/fbcon.c:2677 con_font_set drivers/tty/vt/vt.c:4524 [inline] con_font_op+0xd3e/0x1130 drivers/tty/vt/vt.c:4589 vt_ioctl+0xcd0/0x2500 drivers/tty/vt/vt_ioctl.c:928 tty_ioctl+0x7a1/0x1420 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: 0033:0x45c829 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:00007f8c69d10c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e9420 RCX: 000000000045c829 RDX: 0000000020000080 RSI: 0000000000004b61 RDI: 0000000000000003 RBP: 000000000078bfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000421 R14: 00000000004c6c18 R15: 00007f8c69d116d4