syzbot


INFO: task hung in fuse_lookup (2)

Status: closed as dup on 2018/09/10 08:43
Subsystems: fuse
[Documentation on labels]
Reported-by: syzbot+1f2de7c1f418ee2aafd2@syzkaller.appspotmail.com
First crash: 2050d, last: 1889d
Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
INFO: task hung in __fuse_request_send fuse C 1746 1889d 2108d
Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 INFO: task hung in fuse_lookup 4 1662d 1815d 0/1 auto-closed as invalid on 2020/01/29 21:30
linux-4.19 INFO: task hung in fuse_lookup reiserfs C error 12 433d 1711d 0/1 upstream: reported C repro on 2019/08/14 05:24
linux-4.14 INFO: task hung in fuse_lookup (3) 1 826d 826d 0/1 auto-closed as invalid on 2022/05/15 00:47
linux-6.1 INFO: task hung in fuse_lookup origin:upstream syz 3 19d 318d 0/3 upstream: reported syz repro on 2023/06/07 05:32
upstream INFO: task hung in fuse_lookup (3) fuse C done error 46 3d04h 1711d 0/26 upstream: reported C repro on 2019/08/14 09:48
linux-5.15 INFO: task hung in fuse_lookup origin:upstream syz error 2 297d 318d 0/3 upstream: reported syz repro on 2023/06/07 02:49
linux-4.14 INFO: task hung in fuse_lookup (4) reiserfs C 2 439d 494d 0/1 upstream: reported C repro on 2022/12/13 09:09
linux-4.14 INFO: task hung in fuse_lookup (2) 1 1496d 1496d 0/1 auto-closed as invalid on 2020/07/13 23:30
upstream INFO: task hung in fuse_lookup fuse 16 2055d 2107d 0/26 closed as invalid on 2018/09/05 12:51
android-49 INFO: task hung in fuse_lookup C 112 1624d 1836d 0/3 public: reported C repro on 2019/04/11 08:44

Sample crash report:
INFO: task syz-executor295:7582 blocked for more than 140 seconds.
      Not tainted 5.0.0-rc6-next-20190215 #36
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor295 D28064  7582   7580 0x00000000
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 fuse_lock_inode+0xba/0xf0 fs/fuse/inode.c:367
 fuse_lookup+0x8e/0x350 fs/fuse/dir.c:335
 __lookup_slow+0x27e/0x500 fs/namei.c:1669
 lookup_slow+0x58/0x80 fs/namei.c:1686
 walk_component+0x74b/0x2000 fs/namei.c:1808
 link_path_walk.part.0+0x980/0x1340 fs/namei.c:2139
 link_path_walk fs/namei.c:2070 [inline]
 path_openat+0x202/0x46e0 fs/namei.c:3532
 do_filp_open+0x1a1/0x280 fs/namei.c:3563
 do_sys_open+0x3fe/0x5d0 fs/open.c:1063
 __do_sys_open fs/open.c:1081 [inline]
 __se_sys_open fs/open.c:1076 [inline]
 __x64_sys_open+0x7e/0xc0 fs/open.c:1076
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x444910
Code: Bad RIP value.
RSP: 002b:00007ffc6a7035d0 EFLAGS: 00000202 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000444910
RDX: 0000000000000000 RSI: 0000000000090800 RDI: 00000000004ae75e
RBP: 0000000000001db9 R08: 0000000000001d9e R09: 00000000019ff880
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffc6a703800
R13: 0000000000407360 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor295:7610 blocked for more than 140 seconds.
      Not tainted 5.0.0-rc6-next-20190215 #36
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor295 D28176  7610   7582 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3620
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0x726/0x1310 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 fuse_lock_inode+0xba/0xf0 fs/fuse/inode.c:367
 fuse_lookup+0x8e/0x350 fs/fuse/dir.c:335
 __lookup_slow+0x27e/0x500 fs/namei.c:1669
 lookup_slow+0x58/0x80 fs/namei.c:1686
 walk_component+0x74b/0x2000 fs/namei.c:1808
 link_path_walk.part.0+0x980/0x1340 fs/namei.c:2139
 link_path_walk fs/namei.c:2070 [inline]
 path_openat+0x202/0x46e0 fs/namei.c:3532
 do_filp_open+0x1a1/0x280 fs/namei.c:3563
 do_sys_open+0x3fe/0x5d0 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+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446519
Code: Bad RIP value.
RSP: 002b:00007f2ba34efdb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 0000000000446519
RDX: 0000000000000002 RSI: 00000000200002c0 RDI: ffffffffffffff9c
RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c
R13: 00007ffc6a70376f R14: 00007f2ba34f09c0 R15: 20c49ba5e353f7cf
INFO: task syz-executor295:7613 blocked for more than 140 seconds.
      Not tainted 5.0.0-rc6-next-20190215 #36
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor295 D27944  7613   7582 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2877 [inline]
 __schedule+0x817/0x1cc0 kernel/sched/core.c:3518
 schedule+0x92/0x180 kernel/sched/core.c:3562
 d_wait_lookup fs/dcache.c:2436 [inline]
 d_alloc_parallel+0x11cc/0x1bc0 fs/dcache.c:2518
 __lookup_slow+0x1ab/0x500 fs/namei.c:1652
 lookup_slow+0x58/0x80 fs/namei.c:1686
 walk_component+0x74b/0x2000 fs/namei.c:1808
 link_path_walk.part.0+0x980/0x1340 fs/namei.c:2139
 link_path_walk fs/namei.c:2070 [inline]
 path_openat+0x202/0x46e0 fs/namei.c:3532
 do_filp_open+0x1a1/0x280 fs/namei.c:3563
 do_sys_open+0x3fe/0x5d0 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+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x446519
Code: Bad RIP value.
RSP: 002b:00007f2ba34addb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00000000006dbc48 RCX: 0000000000446519
RDX: 0000000000000002 RSI: 00000000200002c0 RDI: ffffffffffffff9c
RBP: 00000000006dbc40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc4c
R13: 00007ffc6a70376f R14: 00007f2ba34ae9c0 R15: 20c49ba5e353f7cf

Showing all locks held in the system:
2 locks held by init/1:
 #0: 0000000091d74dd6 (&type->i_mutex_dir_key#6){++++}, at: inode_lock_shared include/linux/fs.h:773 [inline]
 #0: 0000000091d74dd6 (&type->i_mutex_dir_key#6){++++}, at: lookup_slow+0x4a/0x80 fs/namei.c:1685
 #1: 0000000071c69d9c (&fi->mutex){+.+.}, at: fuse_lock_inode+0xba/0xf0 fs/fuse/inode.c:367
1 lock held by khungtaskd/1041:
 #0: 000000008bf46afc (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4382
1 lock held by rsyslogd/7467:
 #0: 000000003cde5b4e (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801
2 locks held by cron/7507:
 #0: 0000000091d74dd6 (&type->i_mutex_dir_key#6){++++}, at: inode_lock_shared include/linux/fs.h:773 [inline]
 #0: 0000000091d74dd6 (&type->i_mutex_dir_key#6){++++}, at: lookup_slow+0x4a/0x80 fs/namei.c:1685
 #1: 0000000071c69d9c (&fi->mutex){+.+.}, at: fuse_lock_inode+0xba/0xf0 fs/fuse/inode.c:367
2 locks held by getty/7557:
 #0: 0000000097251136 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000587fe815 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7558:
 #0: 000000008ee8fc18 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000ac5d350f (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7559:
 #0: 00000000ed67a12d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000f7815014 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7560:
 #0: 000000009338420e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 000000000b319607 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7561:
 #0: 000000006d026e86 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000a75c04a8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7562:
 #0: 00000000ed701322 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000023d9928 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7563:
 #0: 0000000028bfd701 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
 #1: 00000000c5a34606 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by syz-executor295/7582:
 #0: 0000000091d74dd6 (&type->i_mutex_dir_key#6){++++}, at: inode_lock_shared include/linux/fs.h:773 [inline]
 #0: 0000000091d74dd6 (&type->i_mutex_dir_key#6){++++}, at: lookup_slow+0x4a/0x80 fs/namei.c:1685
 #1: 0000000071c69d9c (&fi->mutex){+.+.}, at: fuse_lock_inode+0xba/0xf0 fs/fuse/inode.c:367
2 locks held by syz-executor295/7610:
 #0: 0000000091d74dd6 (&type->i_mutex_dir_key#6){++++}, at: inode_lock_shared include/linux/fs.h:773 [inline]
 #0: 0000000091d74dd6 (&type->i_mutex_dir_key#6){++++}, at: lookup_slow+0x4a/0x80 fs/namei.c:1685
 #1: 0000000071c69d9c (&fi->mutex){+.+.}, at: fuse_lock_inode+0xba/0xf0 fs/fuse/inode.c:367
1 lock held by syz-executor295/7613:
 #0: 0000000091d74dd6 (&type->i_mutex_dir_key#6){++++}, at: inode_lock_shared include/linux/fs.h:773 [inline]
 #0: 0000000091d74dd6 (&type->i_mutex_dir_key#6){++++}, at: lookup_slow+0x4a/0x80 fs/namei.c:1685

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1041 Comm: khungtaskd Not tainted 5.0.0-rc6-next-20190215 #36
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+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1be/0x236 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:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline]
 watchdog+0x9b2/0xeb0 kernel/hung_task.c:288
 kthread+0x357/0x430 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 0 to CPUs 1:

Crashes (13):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/02/17 04:45 linux-next 7a92eb7cc1dc f42dee6d .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/01/28 17:23 upstream f17b5f06cb92 629c2a27 .config console log report ci-upstream-kasan-gce-root
2019/01/06 19:03 upstream b5aef86e089a 94f8adb5 .config console log report ci-upstream-kasan-gce-root
2018/12/24 04:46 upstream 3c730b1041ae e3bd7ab8 .config console log report ci-upstream-kasan-gce-smack-root
2018/11/09 09:22 upstream 24ccea7e102d 8fd01d3a .config console log report ci-upstream-kasan-gce-root
2018/10/24 10:30 upstream 44786880df19 a8292de9 .config console log report ci-upstream-kasan-gce-selinux-root
2018/10/16 10:01 upstream f0a7d1883d9f 8cd30605 .config console log report ci-upstream-kasan-gce-smack-root
2018/10/01 18:38 upstream 17b57b1883c1 48a50c6b .config console log report ci-upstream-kasan-gce-smack-root
2018/09/26 18:09 upstream a38523185b40 455b6354 .config console log report ci-upstream-kasan-gce-smack-root
2018/09/25 05:27 upstream 02214bfc89c7 0e7547d7 .config console log report ci-upstream-kasan-gce-smack-root
2018/09/21 00:49 upstream ae596de1a0c8 6cee973c .config console log report ci-upstream-kasan-gce-smack-root
2018/09/09 02:05 upstream d7b686ebf704 6b5120a4 .config console log report ci-upstream-kasan-gce-selinux-root
2019/01/03 20:00 linux-next a4983672f9ca 66fcd29b .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.