syzbot


INFO: task hung in vfs_unlink (2)

Status: auto-closed as invalid on 2020/12/05 18:54
Reported-by: syzbot+08ee2bfc429dd0f74021@syzkaller.appspotmail.com
First crash: 1417d, last: 1355d
Similar bugs (13)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in vfs_unlink (3) 2 24d 35d 0/3 upstream: reported on 2024/03/19 12:40
linux-6.1 INFO: task hung in vfs_unlink (2) 1 152d 152d 0/3 auto-obsoleted due to no activity on 2024/03/02 11:45
linux-4.14 INFO: task hung in vfs_unlink (2) 1 1101d 1101d 0/1 auto-closed as invalid on 2021/08/17 05:41
linux-4.14 INFO: task hung in vfs_unlink 8 1346d 1587d 0/1 auto-closed as invalid on 2020/12/15 00:37
linux-4.19 INFO: task hung in vfs_unlink (4) 1 532d 532d 0/1 auto-obsoleted due to no activity on 2023/03/09 01:26
upstream INFO: task hung in vfs_unlink (3) ext4 1 450d 450d 0/26 auto-obsoleted due to no activity on 2023/04/30 04:19
linux-5.15 INFO: task hung in vfs_unlink 29 37d 394d 0/3 upstream: reported on 2023/03/26 16:46
upstream INFO: task hung in vfs_unlink ext4 32 1368d 1645d 0/26 auto-closed as invalid on 2020/11/23 01:14
linux-6.1 INFO: task hung in vfs_unlink 2 342d 353d 0/3 auto-obsoleted due to no activity on 2023/08/26 02:49
linux-4.19 INFO: task hung in vfs_unlink 6 1546d 1671d 0/1 auto-closed as invalid on 2020/05/28 17:30
linux-4.19 INFO: task hung in vfs_unlink (3) 1 994d 994d 0/1 auto-closed as invalid on 2021/12/01 23:35
upstream INFO: task hung in vfs_unlink (4) fs 6 188d 348d 0/26 auto-obsoleted due to no activity on 2024/01/16 15:08
upstream INFO: task hung in vfs_unlink (2) fs 1 626d 626d 0/26 auto-closed as invalid on 2022/10/05 08:13

Sample crash report:
INFO: task syz-executor.0:6503 blocked for more than 140 seconds.
      Not tainted 4.19.138-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D23832  6503      1 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]
 vfs_unlink+0xca/0x4e0 fs/namei.c:3993
 do_unlinkat+0x3b8/0x660 fs/namei.c:4065
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45cbc7
Code: 00 66 90 b8 58 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 cd b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff5d25e1c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045cbc7
RDX: 00007fff5d25e1e0 RSI: 00007fff5d25e1e0 RDI: 00007fff5d25e270
RBP: 00000000000027f9 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000003 R11: 0000000000000246 R12: 00007fff5d25f300
R13: 0000000002baea60 R14: 0000000000000000 R15: 00007fff5d25f300
INFO: task syz-executor.1:6615 blocked for more than 140 seconds.
      Not tainted 4.19.138-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D24192  6615      1 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]
 vfs_unlink+0xca/0x4e0 fs/namei.c:3993
 do_unlinkat+0x3b8/0x660 fs/namei.c:4065
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45cbc7
Code: Bad RIP value.
RSP: 002b:00007ffc43c164f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045cbc7
RDX: 00007ffc43c16510 RSI: 00007ffc43c16510 RDI: 00007ffc43c165a0
RBP: 00000000000029c7 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000003 R11: 0000000000000246 R12: 00007ffc43c17630
R13: 000000000303ba60 R14: 0000000000000000 R15: 00007ffc43c17630
INFO: task syz-executor.2:6756 blocked for more than 140 seconds.
      Not tainted 4.19.138-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D24192  6756      1 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]
 vfs_unlink+0xca/0x4e0 fs/namei.c:3993
 do_unlinkat+0x3b8/0x660 fs/namei.c:4065
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45cbc7
Code: Bad RIP value.
RSP: 002b:00007ffdd1d1e2d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045cbc7
RDX: 00007ffdd1d1e2f0 RSI: 00007ffdd1d1e2f0 RDI: 00007ffdd1d1e380
RBP: 0000000000002790 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000003 R11: 0000000000000246 R12: 00007ffdd1d1f410
R13: 000000000368ba60 R14: 0000000000000000 R15: 00007ffdd1d1f410
INFO: task syz-executor.5:7091 blocked for more than 140 seconds.
      Not tainted 4.19.138-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D23952  7091      1 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]
 vfs_unlink+0xca/0x4e0 fs/namei.c:3993
 do_unlinkat+0x3b8/0x660 fs/namei.c:4065
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45cbc7
Code: Bad RIP value.
RSP: 002b:00007fff45c08ae8 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045cbc7
RDX: 00007fff45c08b00 RSI: 00007fff45c08b00 RDI: 00007fff45c08b90
RBP: 000000000000269a R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000003 R11: 0000000000000246 R12: 00007fff45c09c20
R13: 00000000032cba60 R14: 0000000000000000 R15: 00007fff45c09c20

Showing all locks held in the system:
2 locks held by kworker/u4:5/432:
 #0: 000000008aa8f038 (&rq->lock){-.-.}, at: idle_balance kernel/sched/fair.c:9696 [inline]
 #0: 000000008aa8f038 (&rq->lock){-.-.}, at: pick_next_task_fair+0x556/0x1570 kernel/sched/fair.c:6840
 #1: 000000008a54b266 (rcu_read_lock){....}, at: cpu_of kernel/sched/sched.h:927 [inline]
 #1: 000000008a54b266 (rcu_read_lock){....}, at: __update_idle_core+0x39/0x3e0 kernel/sched/fair.c:6057
1 lock held by khungtaskd/1089:
 #0: 000000008a54b266 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440
1 lock held by in:imklog/6175:
 #0: 000000000552d4a9 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
3 locks held by rs:main Q:Reg/6176:
 #0: 000000007a1ef621 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
 #1: 00000000ead49b0c (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2776 [inline]
 #1: 00000000ead49b0c (sb_writers#3){.+.+}, at: vfs_write+0x463/0x540 fs/read_write.c:548
 #2: 00000000714cc463 (&sb->s_type->i_mutex_key#9){++++}, at: inode_trylock include/linux/fs.h:768 [inline]
 #2: 00000000714cc463 (&sb->s_type->i_mutex_key#9){++++}, at: ext4_file_write_iter+0x21f/0xf20 fs/ext4/file.c:238
3 locks held by syz-executor.0/6503:
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360
 #1: 00000000e17f32f8 (&type->i_mutex_dir_key#3/1){+.+.}, at: inode_lock_nested include/linux/fs.h:783 [inline]
 #1: 00000000e17f32f8 (&type->i_mutex_dir_key#3/1){+.+.}, at: do_unlinkat+0x27d/0x660 fs/namei.c:4051
 #2: 00000000fc29fcf3 (&sb->s_type->i_mutex_key#9){++++}, at: inode_lock include/linux/fs.h:748 [inline]
 #2: 00000000fc29fcf3 (&sb->s_type->i_mutex_key#9){++++}, at: vfs_unlink+0xca/0x4e0 fs/namei.c:3993
3 locks held by syz-executor.1/6615:
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360
 #1: 00000000149563b8 (&type->i_mutex_dir_key#3/1){+.+.}, at: inode_lock_nested include/linux/fs.h:783 [inline]
 #1: 00000000149563b8 (&type->i_mutex_dir_key#3/1){+.+.}, at: do_unlinkat+0x27d/0x660 fs/namei.c:4051
 #2: 00000000bcd1a959 (&sb->s_type->i_mutex_key#9){++++}, at: inode_lock include/linux/fs.h:748 [inline]
 #2: 00000000bcd1a959 (&sb->s_type->i_mutex_key#9){++++}, at: vfs_unlink+0xca/0x4e0 fs/namei.c:3993
3 locks held by syz-executor.2/6756:
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360
 #1: 00000000e46ef28d (&type->i_mutex_dir_key#3/1){+.+.}, at: inode_lock_nested include/linux/fs.h:783 [inline]
 #1: 00000000e46ef28d (&type->i_mutex_dir_key#3/1){+.+.}, at: do_unlinkat+0x27d/0x660 fs/namei.c:4051
 #2: 00000000f4091b5b (&sb->s_type->i_mutex_key#9){++++}, at: inode_lock include/linux/fs.h:748 [inline]
 #2: 00000000f4091b5b (&sb->s_type->i_mutex_key#9){++++}, at: vfs_unlink+0xca/0x4e0 fs/namei.c:3993
3 locks held by syz-executor.5/7091:
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: sb_start_write include/linux/fs.h:1579 [inline]
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:360
 #1: 0000000050f1d119 (&type->i_mutex_dir_key#3/1){+.+.}, at: inode_lock_nested include/linux/fs.h:783 [inline]
 #1: 0000000050f1d119 (&type->i_mutex_dir_key#3/1){+.+.}, at: do_unlinkat+0x27d/0x660 fs/namei.c:4051
 #2: 0000000057dec6cd (&sb->s_type->i_mutex_key#9){++++}, at: inode_lock include/linux/fs.h:748 [inline]
 #2: 0000000057dec6cd (&sb->s_type->i_mutex_key#9){++++}, at: vfs_unlink+0xca/0x4e0 fs/namei.c:3993
2 locks held by syz-executor.1/8650:
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2776 [inline]
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: vfs_write+0x463/0x540 fs/read_write.c:548
 #1: 00000000bcd1a959 (&sb->s_type->i_mutex_key#9){++++}, at: inode_trylock include/linux/fs.h:768 [inline]
 #1: 00000000bcd1a959 (&sb->s_type->i_mutex_key#9){++++}, at: ext4_file_write_iter+0x21f/0xf20 fs/ext4/file.c:238
2 locks held by syz-executor.2/8654:
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2776 [inline]
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: vfs_write+0x463/0x540 fs/read_write.c:548
 #1: 00000000f4091b5b (&sb->s_type->i_mutex_key#9){++++}, at: inode_trylock include/linux/fs.h:768 [inline]
 #1: 00000000f4091b5b (&sb->s_type->i_mutex_key#9){++++}, at: ext4_file_write_iter+0x21f/0xf20 fs/ext4/file.c:238
2 locks held by syz-executor.0/8670:
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2776 [inline]
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: vfs_write+0x463/0x540 fs/read_write.c:548
 #1: 00000000fc29fcf3 (&sb->s_type->i_mutex_key#9){++++}, at: inode_trylock include/linux/fs.h:768 [inline]
 #1: 00000000fc29fcf3 (&sb->s_type->i_mutex_key#9){++++}, at: ext4_file_write_iter+0x21f/0xf20 fs/ext4/file.c:238
2 locks held by syz-executor.5/8672:
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2776 [inline]
 #0: 00000000ead49b0c (sb_writers#3){.+.+}, at: vfs_write+0x463/0x540 fs/read_write.c:548
 #1: 0000000057dec6cd (&sb->s_type->i_mutex_key#9){++++}, at: inode_trylock include/linux/fs.h:768 [inline]
 #1: 0000000057dec6cd (&sb->s_type->i_mutex_key#9){++++}, at: ext4_file_write_iter+0x21f/0xf20 fs/ext4/file.c:238

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

NMI backtrace for cpu 1
CPU: 1 PID: 1089 Comm: khungtaskd Not tainted 4.19.138-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+0x1fc/0x2fe 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+0x991/0xe60 kernel/hung_task.c:287
 kthread+0x30b/0x410 kernel/kthread.c:246
 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: 3707 Comm: systemd-journal Not tainted 4.19.138-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:write_comp_data+0x23/0x70 kernel/kcov.c:122
Code: 1f 84 00 00 00 00 00 49 89 f1 49 89 fa 65 48 8b 34 25 40 ee 01 00 65 8b 05 aa 3d 98 7e a9 00 01 1f 00 75 4f 8b 86 d8 12 00 00 <83> f8 03 75 44 48 8b 86 e0 12 00 00 8b b6 dc 12 00 00 48 8b 38 48
RSP: 0018:ffff888093e1fb00 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff816ee268
RDX: 0000000000000000 RSI: ffff888093e12640 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: ffff888091a99930
R13: ffffffff819fe4cd R14: ffff88812c2dfc80 R15: 0000000000000286
FS:  00007fe71999e8c0(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe715fda000 CR3: 0000000093e9a000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 trace_irq_enable_rcuidle include/trace/events/preemptirq.h:40 [inline]
 trace_hardirqs_on+0xd8/0x210 kernel/trace/trace_preemptirq.c:25
 qlink_free mm/kasan/quarantine.c:150 [inline]
 qlist_free_all+0xed/0x140 mm/kasan/quarantine.c:166
 quarantine_reduce+0x1a9/0x230 mm/kasan/quarantine.c:259
 kasan_kmalloc+0xa2/0x160 mm/kasan/kasan.c:538
 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
 getname_flags+0xce/0x590 fs/namei.c:140
 getname fs/namei.c:211 [inline]
 user_path_create fs/namei.c:3696 [inline]
 do_mkdirat+0x8d/0x2d0 fs/namei.c:3834
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7fe718c5a687
Code: 00 b8 ff ff ff ff c3 0f 1f 40 00 48 8b 05 09 d8 2b 00 64 c7 00 5f 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 b8 53 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d e1 d7 2b 00 f7 d8 64 89 01 48
RSP: 002b:00007fff4e753ed8 EFLAGS: 00000293 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007fff4e756f40 RCX: 00007fe718c5a687
RDX: 0000000000000000 RSI: 00000000000001ed RDI: 000055bc92ea78c0
RBP: 00007fff4e753f10 R08: 000055bc927a83e5 R09: 0000000000000018
R10: 0000000000000069 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000001 R14: 000055bc92ea78c0 R15: 00007fff4e754550

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/08/07 18:53 linux-4.19.y 961f830af065 28ac5c9e .config console log report ci2-linux-4-19
2020/06/06 23:07 linux-4.19.y 4707d8e57273 e6b89e4e .config console log report ci2-linux-4-19
* Struck through repros no longer work on HEAD.