syzbot


INFO: task hung in do_unlinkat

Status: auto-obsoleted due to no activity on 2022/11/17 10:56
Reported-by: syzbot+c977e5cc074e87db11c7@syzkaller.appspotmail.com
First crash: 732d, last: 732d
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in do_unlinkat (2) 1 602d 602d 0/1 auto-obsoleted due to no activity on 2023/03/27 07:50
android-49 INFO: task hung in do_unlinkat 5 2154d 2266d 0/3 auto-closed as invalid on 2019/02/24 11:49
upstream INFO: task hung in do_unlinkat (5) kernfs bcachefs 50 28d 49d 0/27 upstream: reported on 2024/06/02 14:09
upstream INFO: task hung in do_unlinkat (2) fs 4 1260d 1260d 0/27 auto-closed as invalid on 2021/05/17 08:41
upstream INFO: task hung in do_unlinkat exfat 34 2014d 2251d 0/27 closed as dup on 2018/10/27 13:26
upstream INFO: task hung in do_unlinkat (3) fs 2 978d 1021d 0/27 closed as invalid on 2022/02/07 19:19
upstream INFO: task hung in do_unlinkat (4) exfat 4 570d 677d 0/27 auto-obsoleted due to no activity on 2023/04/08 02:53
linux-5.15 INFO: task hung in do_unlinkat 2 1h54m 70d 0/3 upstream: reported on 2024/05/12 15:06

Sample crash report:
loop0: rw=0, want=8208113086, limit=264192
Buffer I/O error on dev loop0, logical block 4104056542, async page read
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
INFO: task syz-executor.4:11129 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D28816 11129   8110 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline]
 rwsem_down_write_failed+0x3aa/0x760 kernel/locking/rwsem-xadd.c:618
 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write_nested+0x51/0x90 kernel/locking/rwsem.c:194
 inode_lock_nested include/linux/fs.h:783 [inline]
 do_unlinkat+0x27d/0x660 fs/namei.c:4051
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fd5e505e1f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd5e39b2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007fd5e5171030 RCX: 00007fd5e505e1f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000
RBP: 00007fd5e50b8161 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff50ee422f R14: 00007fd5e39b2300 R15: 0000000000022000
INFO: task syz-executor.4:11155 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D29744 11155   8110 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline]
 rwsem_down_write_failed+0x3aa/0x760 kernel/locking/rwsem-xadd.c:618
 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write+0x4f/0x90 kernel/locking/rwsem.c:72
 inode_lock include/linux/fs.h:748 [inline]
 do_last fs/namei.c:3324 [inline]
 path_openat+0x1071/0x2df0 fs/namei.c:3537
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fd5e505e1f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd5e3991168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007fd5e5171100 RCX: 00007fd5e505e1f9
RDX: 0000000000000000 RSI: 0000000000141042 RDI: 0000000020000040
RBP: 00007fd5e50b8161 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff50ee422f R14: 00007fd5e3991300 R15: 0000000000022000
INFO: task syz-executor.2:11134 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28816 11134   8109 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline]
 rwsem_down_write_failed+0x3aa/0x760 kernel/locking/rwsem-xadd.c:618
 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write_nested+0x51/0x90 kernel/locking/rwsem.c:194
 inode_lock_nested include/linux/fs.h:783 [inline]
 do_unlinkat+0x27d/0x660 fs/namei.c:4051
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f5f371a51f9
Code: Bad RIP value.
RSP: 002b:00007f5f35af9168 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007f5f372b8030 RCX: 00007f5f371a51f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000000
RBP: 00007f5f371ff161 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcf7842baf R14: 00007f5f35af9300 R15: 0000000000022000
INFO: task syz-executor.2:11145 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D29744 11145   8109 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:589 [inline]
 rwsem_down_write_failed+0x3aa/0x760 kernel/locking/rwsem-xadd.c:618
 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:117
 __down_write arch/x86/include/asm/rwsem.h:142 [inline]
 down_write+0x4f/0x90 kernel/locking/rwsem.c:72
 inode_lock include/linux/fs.h:748 [inline]
 do_last fs/namei.c:3324 [inline]
 path_openat+0x1071/0x2df0 fs/namei.c:3537
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f5f371a51f9
Code: Bad RIP value.
RSP: 002b:00007f5f35ad8168 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f5f372b8100 RCX: 00007f5f371a51f9
RDX: 0000000000000000 RSI: 0000000000141042 RDI: 0000000020000040
RBP: 00007f5f371ff161 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcf7842baf R14: 00007f5f35ad8300 R15: 0000000000022000

Showing all locks held in the system:
1 lock held by khungtaskd/1570:
 #0: 000000002720e3c8 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
1 lock held by in:imklog/7782:
 #0: 00000000b7c72753 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
1 lock held by syz-executor.1/11094:
1 lock held by syz-executor.4/11088:
2 locks held by syz-executor.4/11129:
 #0: 0000000044357f63 (sb_writers#14){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 0000000044357f63 (sb_writers#14){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360
 #1: 00000000549960e2 (&type->i_mutex_dir_key#8/1){+.+.}, at: inode_lock_nested include/linux/fs.h:783 [inline]
 #1: 00000000549960e2 (&type->i_mutex_dir_key#8/1){+.+.}, at: do_unlinkat+0x27d/0x660 fs/namei.c:4051
2 locks held by syz-executor.4/11155:
 #0: 0000000044357f63 (sb_writers#14){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 0000000044357f63 (sb_writers#14){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360
 #1: 00000000549960e2 (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline]
 #1: 00000000549960e2 (&type->i_mutex_dir_key#8){++++}, at: do_last fs/namei.c:3324 [inline]
 #1: 00000000549960e2 (&type->i_mutex_dir_key#8){++++}, at: path_openat+0x1071/0x2df0 fs/namei.c:3537
1 lock held by syz-executor.2/11091:
2 locks held by syz-executor.2/11134:
 #0: 00000000a6dc3315 (sb_writers#14){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 00000000a6dc3315 (sb_writers#14){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360
 #1: 000000008c4e471c (&type->i_mutex_dir_key#8/1){+.+.}, at: inode_lock_nested include/linux/fs.h:783 [inline]
 #1: 000000008c4e471c (&type->i_mutex_dir_key#8/1){+.+.}, at: do_unlinkat+0x27d/0x660 fs/namei.c:4051
2 locks held by syz-executor.2/11145:
 #0: 00000000a6dc3315 (sb_writers#14){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 00000000a6dc3315 (sb_writers#14){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360
 #1: 000000008c4e471c (&type->i_mutex_dir_key#8){++++}, at: inode_lock include/linux/fs.h:748 [inline]
 #1: 000000008c4e471c (&type->i_mutex_dir_key#8){++++}, at: do_last fs/namei.c:3324 [inline]
 #1: 000000008c4e471c (&type->i_mutex_dir_key#8){++++}, at: path_openat+0x1071/0x2df0 fs/namei.c:3537
1 lock held by syz-executor.0/11464:

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

NMI backtrace for cpu 1
CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 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+0x991/0xe60 kernel/hung_task.c:287
 kthread+0x33f/0x460 kernel/kthread.c:259
 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: 11094 Comm: syz-executor.1 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
RIP: 0010:debug_lockdep_rcu_enabled kernel/rcu/update.c:253 [inline]
RIP: 0010:rcu_read_lock_sched_held+0x0/0x1d0 kernel/rcu/update.c:111
Code: c7 c7 60 f1 45 8a e8 8f b0 47 00 eb 81 e8 b8 f4 e6 ff 0f 1f 84 00 00 00 00 00 e9 bb fe ff ff 66 66 2e 0f 1f 84 00 00 00 00 00 <48> c7 c0 44 e0 26 8b 55 48 ba 00 00 00 00 00 fc ff df 48 89 c1 53
RSP: 0018:ffff8880ba007df8 EFLAGS: 00000006
RAX: ffff88809b732100 RBX: ffff8880ba024cc0 RCX: ffffffff81543524
RDX: 0000000000010000 RSI: ffffffff81543774 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffffffff8c665018 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff8c66501b R12: 0000000000000000
R13: ffff88809d762318 R14: ffff8880ba024d40 R15: dffffc0000000000
FS:  00007f550c43d700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f371a51cf CR3: 0000000235ee9000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 trace_hrtimer_expire_exit include/trace/events/timer.h:274 [inline]
 __run_hrtimer kernel/time/hrtimer.c:1466 [inline]
 __hrtimer_run_queues+0xbd9/0xe60 kernel/time/hrtimer.c:1527
 hrtimer_interrupt+0x326/0x9e0 kernel/time/hrtimer.c:1585
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1071 [inline]
 smp_apic_timer_interrupt+0x10c/0x550 arch/x86/kernel/apic/apic.c:1096
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:__orc_find+0x58/0xf0 arch/x86/kernel/unwind_orc.c:46
Code: 00 00 fc ff df 49 89 fe 48 89 fd eb 0c 48 8d 6b 04 49 89 de 49 39 ec 72 4d 4c 89 e0 48 29 e8 48 89 c2 48 c1 e8 3f 48 c1 fa 02 <48> 01 d0 48 d1 f8 48 8d 5c 85 00 48 89 d8 48 c1 e8 03 42 0f b6 14
RSP: 0018:ffff888236b37058 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffffffff8b3d69a0 RCX: ffffffff81f52612
RDX: 0000000000000000 RSI: ffffffff8ba07adc RDI: ffffffff8b3d699c
RBP: ffffffff8b3d69a4 R08: 0000000000000000 R09: ffffffff8ba07adc
R10: ffff888236b3722f R11: 0000000000074071 R12: ffffffff8b3d69a4
R13: ffffffff8b3d699c R14: ffffffff8b3d69a0 R15: dffffc0000000000
 orc_find arch/x86/kernel/unwind_orc.c:159 [inline]
 unwind_next_frame+0x339/0x1400 arch/x86/kernel/unwind_orc.c:422
 __save_stack_trace+0x9f/0x190 arch/x86/kernel/stacktrace.c:44
 save_stack mm/kasan/kasan.c:448 [inline]
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc mm/slab.c:3397 [inline]
 kmem_cache_alloc+0x110/0x370 mm/slab.c:3557
 kmem_cache_zalloc include/linux/slab.h:699 [inline]
 alloc_buffer_head+0x20/0x130 fs/buffer.c:3372
 alloc_page_buffers+0x169/0x5c0 fs/buffer.c:830
 create_empty_buffers+0x2c/0x760 fs/buffer.c:1528
 create_page_buffers+0x212/0x350 fs/buffer.c:1645
 block_read_full_page+0xcf/0xd10 fs/buffer.c:2239
 do_read_cache_page+0x533/0x1170 mm/filemap.c:2828
 read_mapping_page include/linux/pagemap.h:402 [inline]
 dir_get_page fs/minix/dir.c:70 [inline]
 minix_find_entry+0x23a/0x830 fs/minix/dir.c:170
 minix_inode_by_name+0x6d/0x460 fs/minix/dir.c:454
 minix_lookup fs/minix/namei.c:30 [inline]
 minix_lookup+0x103/0x190 fs/minix/namei.c:22
 __lookup_slow+0x246/0x4a0 fs/namei.c:1672
 lookup_slow fs/namei.c:1689 [inline]
 walk_component+0x7ac/0xda0 fs/namei.c:1811
 lookup_last fs/namei.c:2274 [inline]
 path_lookupat+0x1ff/0x8d0 fs/namei.c:2319
 filename_lookup+0x1ac/0x5a0 fs/namei.c:2349
 user_path_at include/linux/namei.h:57 [inline]
 path_setxattr+0x95/0x190 fs/xattr.c:534
 __do_sys_setxattr fs/xattr.c:554 [inline]
 __se_sys_setxattr fs/xattr.c:550 [inline]
 __x64_sys_setxattr+0xc0/0x160 fs/xattr.c:550
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f550dac81f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f550c43d168 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f550dbdaf60 RCX: 00007f550dac81f9
RDX: 00000000200003c0 RSI: 0000000020000380 RDI: 0000000020000080
RBP: 00007f550db22161 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000000000015 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdc688a95f R14: 00007f550c43d300 R15: 0000000000022000

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/07/20 10:56 linux-4.19.y 3f8a27f9e27b 775344bc .config console log report info ci2-linux-4-19 INFO: task hung in do_unlinkat
* Struck through repros no longer work on HEAD.