syzbot


INFO: task hung in lock_rename

Status: auto-obsoleted due to no activity on 2022/10/10 13:20
Reported-by: syzbot+4e756b964598f29d3508@syzkaller.appspotmail.com
First crash: 904d, last: 904d
Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in lock_rename (3) fs 1 1247d 1247d 0/28 auto-closed as invalid on 2021/10/02 18:08
linux-5.15 INFO: task hung in lock_rename 2 581d 613d 0/3 auto-obsoleted due to no activity on 2023/08/23 09:02
upstream INFO: task hung in lock_rename exfat 53 2193d 2328d 0/28 auto-closed as invalid on 2019/05/30 13:09
linux-6.1 INFO: task hung in lock_rename 3 437d 550d 0/3 auto-obsoleted due to no activity on 2024/01/01 05:54
upstream INFO: task hung in lock_rename (4) fs 3 1036d 1130d 0/28 closed as invalid on 2022/02/08 09:40
linux-4.19 INFO: task hung in lock_rename 1 1059d 1059d 0/1 auto-closed as invalid on 2022/05/08 10:15
upstream INFO: task hung in lock_rename (5) fs 2 992d 1021d 0/28 auto-closed as invalid on 2022/06/15 04:15
upstream INFO: task hung in lock_rename (2) fs 7 1398d 1421d 0/28 auto-closed as invalid on 2021/05/17 09:31
android-49 INFO: task hung in lock_rename C 9 2289d 2060d 0/3 public: reported C repro on 2019/04/14 00:00
upstream INFO: task hung in lock_rename (6) ext4 18 583d 832d 0/28 auto-obsoleted due to no activity on 2023/07/28 16:10

Sample crash report:
Bluetooth: hci1 command 0x0406 tx timeout
Bluetooth: hci4 command 0x0406 tx timeout
Bluetooth: hci2 command 0x0406 tx timeout
Bluetooth: hci3 command 0x0406 tx timeout
Bluetooth: hci5 command 0x0406 tx timeout
INFO: task syz-executor.0:9894 blocked for more than 140 seconds.
      Not tainted 4.14.282-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D26720  9894   8005 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:588 [inline]
 rwsem_down_write_failed+0x343/0x6d0 kernel/locking/rwsem-xadd.c:617
 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:105
 __down_write arch/x86/include/asm/rwsem.h:126 [inline]
 down_write_nested+0x51/0x90 kernel/locking/rwsem.c:174
 inode_lock_nested include/linux/fs.h:754 [inline]
 lock_rename+0xd4/0x280 fs/namei.c:2894
 SYSC_renameat2 fs/namei.c:4594 [inline]
 SyS_renameat2+0x5ab/0xad0 fs/namei.c:4533
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7fe98c6fd109
RSP: 002b:00007fe98b072168 EFLAGS: 00000246 ORIG_RAX: 000000000000013c
RAX: ffffffffffffffda RBX: 00007fe98c80ff60 RCX: 00007fe98c6fd109
RDX: 0000000000000006 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 00007fe98c7570ad R08: 0000000000000000 R09: 0000000000000000
R10: 00000000200000c0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcd36308cf R14: 00007fe98b072300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1534:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff87026d5c>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
1 lock held by in:imklog/7700:
 #0:  (&f->f_pos_lock){+.+.}, at: [<ffffffff818d748b>] __fdget_pos+0x1fb/0x2b0 fs/file.c:819
4 locks held by syz-executor.0/9894:
 #0:  (sb_writers#13){.+.+}, at: [<ffffffff818e04fa>] sb_start_write include/linux/fs.h:1551 [inline]
 #0:  (sb_writers#13){.+.+}, at: [<ffffffff818e04fa>] mnt_want_write+0x3a/0xb0 fs/namespace.c:386
 #1:  (&type->s_vfs_rename_key){+.+.}, at: [<ffffffff81891a94>] lock_rename+0x54/0x280 fs/namei.c:2889
 #2:  (&type->i_mutex_dir_key#8/1){+.+.}, at: [<ffffffff81891ae0>] inode_lock_nested include/linux/fs.h:754 [inline]
 #2:  (&type->i_mutex_dir_key#8/1){+.+.}, at: [<ffffffff81891ae0>] lock_rename+0xa0/0x280 fs/namei.c:2893
 #3:  (&type->i_mutex_dir_key#8/2){+.+.}, at: [<ffffffff81891b14>] inode_lock_nested include/linux/fs.h:754 [inline]
 #3:  (&type->i_mutex_dir_key#8/2){+.+.}, at: [<ffffffff81891b14>] lock_rename+0xd4/0x280 fs/namei.c:2894

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

NMI backtrace for cpu 1
CPU: 1 PID: 1534 Comm: khungtaskd Not tainted 4.14.282-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3 Comm: kworker/0:0 Not tainted 4.14.282-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_long gc_worker
task: ffff8880b5fe80c0 task.stack: ffff8880b5ff0000
RIP: 0010:task_irq_context kernel/locking/lockdep.c:3101 [inline]
RIP: 0010:__lock_acquire+0x435/0x3f20 kernel/locking/lockdep.c:3436
RSP: 0018:ffff8880b5ff7ab0 EFLAGS: 00000803
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 1ffff11016bfd132 RDI: ffff8880b5fe8934
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: ffff8880b5fe8998 R11: ffff8880b5fe80c0 R12: ffff8880b5fe89b0
R13: 0000000000000012 R14: 0000000000000012 R15: ffffffff8bed1d40
FS:  0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6be0d28000 CR3: 00000000a1e75000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
 rcu_lock_acquire include/linux/rcupdate.h:242 [inline]
 rcu_read_lock include/linux/rcupdate.h:629 [inline]
 gc_worker+0x12e/0xb50 net/netfilter/nf_conntrack_core.c:1084
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: 83 54 08 00 00 49 8d bb 74 08 00 00 ba 02 00 00 00 48 89 f9 85 c0 0f 45 c2 48 c1 e9 03 48 ba 00 00 00 00 00 fc ff df 0f b6 0c 11 <48> 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 dd 25 00 00 
----------------
Code disassembly (best guess):
   0:	83 54 08 00 00       	adcl   $0x0,0x0(%rax,%rcx,1)
   5:	49 8d bb 74 08 00 00 	lea    0x874(%r11),%rdi
   c:	ba 02 00 00 00       	mov    $0x2,%edx
  11:	48 89 f9             	mov    %rdi,%rcx
  14:	85 c0                	test   %eax,%eax
  16:	0f 45 c2             	cmovne %edx,%eax
  19:	48 c1 e9 03          	shr    $0x3,%rcx
  1d:	48 ba 00 00 00 00 00 	movabs $0xdffffc0000000000,%rdx
  24:	fc ff df
  27:	0f b6 0c 11          	movzbl (%rcx,%rdx,1),%ecx
* 2b:	48 89 fa             	mov    %rdi,%rdx <-- trapping instruction
  2e:	83 e2 07             	and    $0x7,%edx
  31:	83 c2 03             	add    $0x3,%edx
  34:	38 ca                	cmp    %cl,%dl
  36:	7c 08                	jl     0x40
  38:	84 c9                	test   %cl,%cl
  3a:	0f 85 dd 25 00 00    	jne    0x261d

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/06/12 13:20 linux-4.14.y b8f3be299d51 0d5abf15 .config console log report info ci2-linux-4-14 INFO: task hung in lock_rename
* Struck through repros no longer work on HEAD.