syzbot


INFO: task hung in filename_create (2)

Status: upstream: reported C repro on 2024/11/26 07:48
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+4337a9544ad38c676780@syzkaller.appspotmail.com
First crash: 143d, last: 16d
Bug presence (1)
Date Name Commit Repro Result
2025/01/05 upstream (ToT) ab75170520d4 C [report] WARNING in inc_nlink
Similar bugs (14)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in filename_create 6 1978d 2077d 0/1 auto-closed as invalid on 2020/03/17 23:03
upstream INFO: task hung in filename_create (2) fs 11 1961d 2066d 0/28 auto-closed as invalid on 2020/03/04 11:54
android-49 INFO: task hung in filename_create C 44 2427d 2198d 0/3 public: reported C repro on 2019/04/13 00:00
upstream INFO: task hung in filename_create (3) fs 16 1427d 1583d 0/28 auto-closed as invalid on 2021/08/20 18:08
linux-4.19 INFO: task hung in filename_create (3) 3 1255d 1317d 0/1 auto-closed as invalid on 2022/03/11 04:15
android-44 INFO: task hung in filename_create 1 2560d 2560d 0/2 auto-closed as invalid on 2019/02/22 14:19
linux-4.19 INFO: task hung in filename_create (2) 1 1518d 1518d 0/1 auto-closed as invalid on 2021/06/20 16:38
linux-4.14 INFO: task hung in filename_create 2 1951d 1955d 0/1 auto-closed as invalid on 2020/04/14 04:42
linux-4.19 INFO: task hung in filename_create (4) 2 888d 951d 0/1 auto-obsoleted due to no activity on 2023/03/13 04:19
linux-5.15 INFO: task hung in filename_create origin:upstream C 48 12d 369d 0/3 upstream: reported C repro on 2024/04/15 05:31
android-44 INFO: task hung in filename_create (2) 1 2181d 2181d 0/2 auto-closed as invalid on 2019/10/25 08:49
upstream INFO: task hung in filename_create (4) fs C error error 2106 1d00h 1214d 0/28 upstream: reported C repro on 2021/12/21 22:55
linux-6.1 INFO: task hung in filename_create 6 339d 364d 0/3 auto-obsoleted due to no activity on 2024/08/23 04:31
upstream INFO: task hung in filename_create fs 121 2271d 2556d 0/28 closed as dup on 2018/09/08 15:39
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2025/04/02 07:14 2h56m bisect fix linux-6.1.y OK (0) job log log
2025/02/04 09:54 1h36m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
INFO: task syz-executor361:4266 blocked for more than 143 seconds.
      Tainted: G        W          6.1.122-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor361 state:D stack:29336 pid:4266  ppid:4247   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189
 inode_lock_nested include/linux/fs.h:793 [inline]
 filename_create+0x25c/0x530 fs/namei.c:3876
 do_mkdirat+0xba/0x360 fs/namei.c:4121
 __do_sys_mkdir fs/namei.c:4151 [inline]
 __se_sys_mkdir fs/namei.c:4149 [inline]
 __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4149
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f92690ecd89
RSP: 002b:00007f9269088228 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f926917e6b8 RCX: 00007f92690ecd89
RDX: 00007f92690c6316 RSI: 0000000000000000 RDI: 0000000020000080
RBP: 00007f926917e6b0 R08: 00007ffc82c71207 R09: 00007f92690886c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f926917e6bc
R13: 0031656c69662f2e R14: 00007f9269141160 R15: 00007ffc82c71208
 </TASK>
INFO: task syz-executor361:4265 blocked for more than 144 seconds.
      Tainted: G        W          6.1.122-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor361 state:D stack:29336 pid:4265  ppid:4249   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189
 inode_lock_nested include/linux/fs.h:793 [inline]
 filename_create+0x25c/0x530 fs/namei.c:3876
 do_mkdirat+0xba/0x360 fs/namei.c:4121
 __do_sys_mkdir fs/namei.c:4151 [inline]
 __se_sys_mkdir fs/namei.c:4149 [inline]
 __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4149
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f92690ecd89
RSP: 002b:00007f9269088228 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f926917e6b8 RCX: 00007f92690ecd89
RDX: 00007f92690c6316 RSI: 0000000000000000 RDI: 0000000020000080
RBP: 00007f926917e6b0 R08: 00007ffc82c71207 R09: 00007f92690886c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f926917e6bc
R13: 0031656c69662f2e R14: 00007f9269141160 R15: 00007ffc82c71208
 </TASK>
INFO: task syz-executor361:4263 blocked for more than 145 seconds.
      Tainted: G        W          6.1.122-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor361 state:D stack:29336 pid:4263  ppid:4250   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189
 inode_lock_nested include/linux/fs.h:793 [inline]
 filename_create+0x25c/0x530 fs/namei.c:3876
 do_mkdirat+0xba/0x360 fs/namei.c:4121
 __do_sys_mkdir fs/namei.c:4151 [inline]
 __se_sys_mkdir fs/namei.c:4149 [inline]
 __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4149
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f92690ecd89
RSP: 002b:00007f9269088228 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f926917e6b8 RCX: 00007f92690ecd89
RDX: 00007f92690c6316 RSI: 0000000000000000 RDI: 0000000020000080
RBP: 00007f926917e6b0 R08: 00007ffc82c71207 R09: 00007f92690886c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f926917e6bc
R13: 0031656c69662f2e R14: 00007f9269141160 R15: 00007ffc82c71208
 </TASK>
INFO: task syz-executor361:4264 blocked for more than 145 seconds.
      Tainted: G        W          6.1.122-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor361 state:D stack:28464 pid:4264  ppid:4251   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189
 inode_lock_nested include/linux/fs.h:793 [inline]
 filename_create+0x25c/0x530 fs/namei.c:3876
 do_mkdirat+0xba/0x360 fs/namei.c:4121
 __do_sys_mkdir fs/namei.c:4151 [inline]
 __se_sys_mkdir fs/namei.c:4149 [inline]
 __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4149
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f92690ecd89
RSP: 002b:00007f9269088228 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f926917e6b8 RCX: 00007f92690ecd89
RDX: 00007f92690c6316 RSI: 0000000000000000 RDI: 0000000020000080
RBP: 00007f926917e6b0 R08: 00007ffc82c71207 R09: 00007f92690886c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f926917e6bc
R13: 0031656c69662f2e R14: 00007f9269141160 R15: 00007ffc82c71208
 </TASK>
INFO: task syz-executor361:4267 blocked for more than 146 seconds.
      Tainted: G        W          6.1.122-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor361 state:D stack:29336 pid:4267  ppid:4248   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189
 inode_lock_nested include/linux/fs.h:793 [inline]
 filename_create+0x25c/0x530 fs/namei.c:3876
 do_mkdirat+0xba/0x360 fs/namei.c:4121
 __do_sys_mkdir fs/namei.c:4151 [inline]
 __se_sys_mkdir fs/namei.c:4149 [inline]
 __x64_sys_mkdir+0x6a/0x80 fs/namei.c:4149
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f92690ecd89
RSP: 002b:00007f9269088228 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007f926917e6b8 RCX: 00007f92690ecd89
RDX: 00007f92690c6316 RSI: 0000000000000000 RDI: 0000000020000080
RBP: 00007f926917e6b0 R08: 00007ffc82c71207 R09: 00007f92690886c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f926917e6bc
R13: 0031656c69662f2e R14: 00007f9269141160 R15: 00007ffc82c71208
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d32b290 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x34/0xde0 kernel/rcu/tasks.h:543
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d32bab0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x34/0xde0 kernel/rcu/tasks.h:543
2 locks held by kworker/1:0/22:
 #0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc900001c7d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
1 lock held by khungtaskd/27:
 #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510
1 lock held by kswapd0/83:
2 locks held by getty/4012:
 #0: ffff888030d4b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198
3 locks held by syz-executor361/4259:
2 locks held by syz-executor361/4266:
 #0: ffff888079844460 (sb_writers#10){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #1: ffff88806e0886d0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
 #1: ffff88806e0886d0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: filename_create+0x25c/0x530 fs/namei.c:3876
2 locks held by syz-executor361/4260:
2 locks held by syz-executor361/4265:
 #0: ffff8880302f2460 (sb_writers#10){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #1: ffff88806e0586d0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
 #1: ffff88806e0586d0 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: filename_create+0x25c/0x530 fs/namei.c:3876
2 locks held by syz-executor361/4257:
2 locks held by syz-executor361/4263:
 #0: ffff888030e78460 (sb_writers#10){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #1: ffff88806e088188 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
 #1: ffff88806e088188 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: filename_create+0x25c/0x530 fs/namei.c:3876
3 locks held by syz-executor361/4262:
2 locks held by syz-executor361/4264:
 #0: ffff8880736dc460 (sb_writers#10){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #1: ffff88806e088c18 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
 #1: ffff88806e088c18 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: filename_create+0x25c/0x530 fs/namei.c:3876
5 locks held by syz-executor361/4258:
2 locks held by syz-executor361/4267:
 #0: ffff888029cf4460 (sb_writers#10){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393
 #1: ffff88806e058188 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:793 [inline]
 #1: ffff88806e058188 (&type->i_mutex_dir_key#6/1){+.+.}-{3:3}, at: filename_create+0x25c/0x530 fs/namei.c:3876
2 locks held by dhcpcd/4292:
 #0: ffff8880244f8130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1750 [inline]
 #0: ffff8880244f8130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xd00 net/packet/af_packet.c:3263
 #1: ffffffff8d3306f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 #1: ffffffff8d3306f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962
1 lock held by dhcpcd/4293:
 #0: ffff88807721c130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1750 [inline]
 #0: ffff88807721c130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xd00 net/packet/af_packet.c:3263

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Tainted: G        W          6.1.122-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1ae/0x3f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf88/0xfd0 kernel/hung_task.c:377
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 11 Comm: kworker/u4:1 Tainted: G        W          6.1.122-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:hlist_del include/linux/list.h:900 [inline]
RIP: 0010:__alloc_object lib/debugobjects.c:214 [inline]
RIP: 0010:alloc_object+0x160/0x6c0 lib/debugobjects.c:227
Code: 49 be 00 00 00 00 00 fc ff df 43 80 3c 34 00 48 8b 1c 24 74 08 48 89 df e8 dd de 98 fd 48 bd 00 01 00 00 00 00 ad de 48 89 2b <43> 80 3c 37 00 74 08 4c 89 ef e8 c1 de 98 fd 48 83 c5 22 49 89 6d
RSP: 0018:ffffc90000107958 EFLAGS: 00000046
RAX: 1ffff1102981840f RBX: ffff88814c0c6f50 RCX: dffffc0000000000
RDX: ffffffff8b0dda80 RSI: ffffffff8b5e67a0 RDI: ffffffff8b5e6760
RBP: dead000000000100 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 1ffff11029818dea
R13: ffff88814c0c6f58 R14: dffffc0000000000 R15: 1ffff11029818deb
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f64e177680 CR3: 000000000d08e000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lookup_object_or_alloc lib/debugobjects.c:588 [inline]
 __debug_object_init+0xe9/0x450 lib/debugobjects.c:623
 init_timer_on_stack_key kernel/time/timer.c:805 [inline]
 schedule_timeout+0x11c/0x300 kernel/time/timer.c:1963
 toggle_allocation_gate+0x23b/0x480 mm/kfence/core.c:811
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/31 03:22 linux-6.1.y 563edd786f0a d3ccff63 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-6-1-kasan INFO: task hung in filename_create
2025/02/28 07:47 linux-6.1.y 3a8358583626 6a8fcbc4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in filename_create
2025/02/23 10:52 linux-6.1.y 3a8358583626 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in filename_create
2024/12/30 22:45 linux-6.1.y 563edd786f0a d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in filename_create
2024/12/11 08:23 linux-6.1.y e4d90d63d385 cfc402b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in filename_create
2024/12/09 06:24 linux-6.1.y e4d90d63d385 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in filename_create
2024/11/26 07:47 linux-6.1.y e4d90d63d385 11dbc254 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in filename_create
* Struck through repros no longer work on HEAD.