syzbot


INFO: task hung in vfs_unlink

Status: auto-closed as invalid on 2020/11/23 01:14
Subsystems: ext4
[Documentation on labels]
Reported-by: syzbot+36feff43582f1f97716a@syzkaller.appspotmail.com
First crash: 2095d, last: 1362d
Discussions (1)
Title Replies (including bot) Last reply
INFO: task hung in vfs_unlink 0 (1) 2019/10/23 07:25
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 18d 30d 0/3 upstream: reported on 2024/03/19 12:40
linux-6.1 INFO: task hung in vfs_unlink (2) 1 147d 147d 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 1095d 1095d 0/1 auto-closed as invalid on 2021/08/17 05:41
linux-4.14 INFO: task hung in vfs_unlink 8 1340d 1582d 0/1 auto-closed as invalid on 2020/12/15 00:37
linux-4.19 INFO: task hung in vfs_unlink (4) 1 526d 526d 0/1 auto-obsoleted due to no activity on 2023/03/09 01:26
linux-4.19 INFO: task hung in vfs_unlink (2) 2 1349d 1411d 0/1 auto-closed as invalid on 2020/12/05 18:54
upstream INFO: task hung in vfs_unlink (3) ext4 1 444d 444d 0/26 auto-obsoleted due to no activity on 2023/04/30 04:19
linux-5.15 INFO: task hung in vfs_unlink 29 31d 388d 0/3 upstream: reported on 2023/03/26 16:46
linux-6.1 INFO: task hung in vfs_unlink 2 336d 347d 0/3 auto-obsoleted due to no activity on 2023/08/26 02:49
linux-4.19 INFO: task hung in vfs_unlink 6 1540d 1665d 0/1 auto-closed as invalid on 2020/05/28 17:30
linux-4.19 INFO: task hung in vfs_unlink (3) 1 988d 988d 0/1 auto-closed as invalid on 2021/12/01 23:35
upstream INFO: task hung in vfs_unlink (4) fs 6 182d 343d 0/26 auto-obsoleted due to no activity on 2024/01/16 15:08
upstream INFO: task hung in vfs_unlink (2) fs 1 621d 621d 0/26 auto-closed as invalid on 2022/10/05 08:13

Sample crash report:
INFO: task syz-executor.5:7602 blocked for more than 143 seconds.
      Not tainted 5.7.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D24216  7602      1 0x00000004
Call Trace:
 schedule+0xd0/0x2a0 kernel/sched/core.c:4163
 rwsem_down_write_slowpath+0x706/0xf90 kernel/locking/rwsem.c:1235
 __down_write kernel/locking/rwsem.c:1389 [inline]
 down_write+0x137/0x150 kernel/locking/rwsem.c:1532
 inode_lock include/linux/fs.h:797 [inline]
 vfs_unlink+0xcd/0x640 fs/namei.c:3800
 do_unlinkat+0x3c4/0x680 fs/namei.c:3873
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45c5d7
Code: Bad RIP value.
RSP: 002b:00007ffd20992128 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045c5d7
RDX: 00007ffd20992140 RSI: 00007ffd20992140 RDI: 00007ffd209921d0
RBP: 000000000000000d R08: 0000000000000000 R09: 0000000000000011
R10: 000000000000000d R11: 0000000000000246 R12: 00007ffd20993260
R13: 000000000100c940 R14: 0000000000000000 R15: 00007ffd20993260

Showing all locks held in the system:
3 locks held by kworker/u4:2/55:
 #0: ffff8880ae637998 (&rq->lock){-.-.}-{2:2}, at: newidle_balance+0x9d9/0xdd0 kernel/sched/fair.c:10512
 #1: ffffffff899bed00 (rcu_read_lock){....}-{1:2}, at: __update_idle_core+0x42/0x3e0 kernel/sched/fair.c:5969
 #2: ffff8880ae627598 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x55/0x1a0 kernel/time/timer.c:936
1 lock held by khungtaskd/1135:
 #0: ffffffff899bed00 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5754
1 lock held by in:imklog/6726:
 #0: ffff8880a32fa3f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826
3 locks held by syz-executor.5/7602:
 #0: ffff8882144a4450 (sb_writers#3){.+.+}-{0:0}, at: sb_start_write include/linux/fs.h:1655 [inline]
 #0: ffff8882144a4450 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x3a/0xb0 fs/namespace.c:354
 #1: ffff888047d823c8 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:832 [inline]
 #1: ffff888047d823c8 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x27d/0x680 fs/namei.c:3859
 #2: ffff888047d88508 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:797 [inline]
 #2: ffff888047d88508 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: vfs_unlink+0xcd/0x640 fs/namei.c:3800
3 locks held by syz-executor.5/8506:
 #0: ffff88809f209bb0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826
 #1: ffff8882144a4450 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2908 [inline]
 #1: ffff8882144a4450 (sb_writers#3){.+.+}-{0:0}, at: vfs_write+0x4cf/0x5d0 fs/read_write.c:558
 #2: ffff888047d88508 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: inode_lock include/linux/fs.h:797 [inline]
 #2: ffff888047d88508 (&sb->s_type->i_mutex_key#9){++++}-{3:3}, at: ext4_buffered_write_iter+0xb3/0x450 fs/ext4/file.c:264

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

NMI backtrace for cpu 1
CPU: 1 PID: 1135 Comm: khungtaskd Not tainted 5.7.0-rc1-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+0x188/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0xa8c/0x1010 kernel/hung_task.c:289
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3428 Comm: kworker/0:4 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events nsim_dev_trap_report_work
RIP: 0010:__orc_find+0x58/0xf0 arch/x86/kernel/unwind_orc.c:47
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 e2 48 29 ea 48 89 d0 48 c1 ea 3f 48 c1 f8 02 <48> 01 c2 48 d1 fa 48 8d 5c 95 00 48 89 d8 48 c1 e8 03 42 0f b6 14
RSP: 0018:ffffc9000a5df6f0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffffffff8a98cac0 RCX: ffffffff81625bbb
RDX: 0000000000000000 RSI: ffffffff8af42828 RDI: ffffffff8a98cab4
RBP: ffffffff8a98cac4 R08: 00000000000168c8 R09: ffffffff8af4286a
R10: 00000000000168be R11: 000000000007001f R12: ffffffff8a98cac4
R13: ffffffff8a98cab4 R14: ffffffff8a98cac0 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5a52300000 CR3: 0000000090dc7000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 orc_find arch/x86/kernel/unwind_orc.c:173 [inline]
 unwind_next_frame+0x34b/0x19d0 arch/x86/kernel/unwind_orc.c:407
 arch_stack_walk+0x74/0xd0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:123
 save_stack+0x1b/0x40 mm/kasan/common.c:49
 set_track mm/kasan/common.c:57 [inline]
 __kasan_kmalloc mm/kasan/common.c:495 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:468
 __kmalloc_reserve.isra.0+0x39/0xe0 net/core/skbuff.c:142
 __alloc_skb+0xef/0x5a0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1083 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:492 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:549 [inline]
 nsim_dev_trap_report_work+0x2bb/0xbc0 drivers/net/netdevsim/dev.c:590
 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268
 worker_thread+0x96/0xe20 kernel/workqueue.c:2414
 kthread+0x388/0x470 kernel/kthread.c:268
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Crashes (32):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/04/15 23:04 upstream 8632e9b5645b 3f3c5574 .config console log report ci-upstream-kasan-gce-selinux-root
2020/02/14 07:43 upstream b19e8c684703 5d7b90f1 .config console log report ci-upstream-kasan-gce-root
2020/02/01 08:31 upstream 26dca6dbd62d 0eb59c27 .config console log report ci-upstream-kasan-gce-smack-root
2020/01/27 19:32 upstream d5226fa6dbae 56cd6c9b .config console log report ci-upstream-kasan-gce-smack-root
2020/01/26 16:54 upstream 2821e26f3a0a dd56146d .config console log report ci-upstream-kasan-gce-smack-root
2019/12/17 19:00 upstream ea200dec5128 a6bc9c88 .config console log report ci-upstream-kasan-gce-root
2019/10/06 09:14 upstream 43b815c6a8e7 f3f7d9c8 .config console log report ci-upstream-kasan-gce-selinux-root
2019/08/25 18:06 upstream e67095fd2f72 d21c5d9d .config console log report ci-upstream-kasan-gce-root
2019/07/30 09:25 upstream 2a11c76e5301 f28bf2a5 .config console log report ci-upstream-kasan-gce-selinux-root
2019/02/13 03:49 upstream 57902dc0670c 1eedba36 .config console log report ci-upstream-kasan-gce-root
2019/01/25 13:30 upstream d73aba1115cf b5d78bce .config console log report ci-upstream-kasan-gce-smack-root
2019/01/13 11:46 upstream e1706720408e c3f3344c .config console log report ci-upstream-kasan-gce
2019/01/01 04:51 upstream f12e840c819b 3d85f48c .config console log report ci-upstream-kasan-gce-root
2018/12/24 11:59 upstream 8fe28cb58bcb be79df56 .config console log report ci-upstream-kasan-gce-selinux-root
2018/12/13 09:18 upstream f5d582777bcb 02613a41 .config console log report ci-upstream-kasan-gce-smack-root
2018/12/06 19:09 upstream cf76c364a1e1 3ab38479 .config console log report ci-upstream-kasan-gce
2018/10/20 11:44 upstream 270b77a0f30e ecb386fe .config console log report ci-upstream-kasan-gce-selinux-root
2018/10/14 18:13 upstream 3a27203102eb caf12900 .config console log report ci-upstream-kasan-gce-smack-root
2018/10/06 20:51 upstream 091a1eaa0e30 8b311eaf .config console log report ci-upstream-kasan-gce-smack-root
2018/10/04 01:36 upstream 6bebe37927f3 8b311eaf .config console log report ci-upstream-kasan-gce-root
2018/10/03 08:47 upstream 1d2ba7fee28b 0f3e0261 .config console log report ci-upstream-kasan-gce-root
2018/09/09 00:03 upstream d7b686ebf704 6b5120a4 .config console log report ci-upstream-kasan-gce-root
2018/09/07 23:16 upstream a49a9dcce802 69cfeb80 .config console log report ci-upstream-kasan-gce
2018/09/03 14:09 upstream 60c1f89241d4 a4718693 .config console log report ci-upstream-kasan-gce-root
2018/07/23 16:55 upstream d72e90f33aa4 f69c5fcd .config console log report ci-upstream-kasan-gce-root
2018/09/30 21:40 upstream 17b57b1883c1 41e4b329 .config console log report ci-upstream-kasan-gce-386
2020/07/26 01:13 linux-next 26027945c94a 1f7cc1ca .config console log report ci-upstream-linux-next-kasan-gce-root
2019/12/15 21:33 linux-next 32b8acf85223 eef6e580 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/02/23 11:00 linux-next 94a47529a645 18107ce0 .config console log report ci-upstream-linux-next-kasan-gce-root
2019/01/10 23:24 linux-next 6cab33afc3dd db9b6579 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/11/07 09:37 linux-next d881de30d29e 8bd6bd63 .config console log report ci-upstream-linux-next-kasan-gce-root
2018/10/13 08:01 linux-next 774ea0551a29 caf12900 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.