syzbot


INFO: task hung in user_get_super (2)

Status: upstream: reported on 2023/11/20 11:19
Reported-by: syzbot+544085f333b2606ba3ff@syzkaller.appspotmail.com
First crash: 217d, last: 18d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in user_get_super 2 434d 441d 0/3 auto-obsoleted due to no activity on 2023/08/15 03:00
upstream INFO: task hung in user_get_super (2) fs C 330 7d14h 218d 0/27 upstream: reported C repro on 2023/11/19 11:27
linux-5.15 INFO: task hung in user_get_super 6 251d 429d 0/3 auto-obsoleted due to no activity on 2024/01/25 03:23
linux-5.15 INFO: task hung in user_get_super (2) 1 86d 86d 0/3 upstream: reported on 2024/03/30 17:00
upstream INFO: task hung in user_get_super fs 1 543d 543d 0/27 auto-obsoleted due to no activity on 2023/04/06 01:17

Sample crash report:
INFO: task syz-executor.2:22104 blocked for more than 143 seconds.
      Not tainted 6.1.92-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:28960 pid:22104 ppid:17825  flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
 rwsem_down_read_slowpath kernel/locking/rwsem.c:1094 [inline]
 __down_read_common kernel/locking/rwsem.c:1261 [inline]
 __down_read kernel/locking/rwsem.c:1274 [inline]
 down_read+0x6ff/0xa30 kernel/locking/rwsem.c:1522
 user_get_super+0x11a/0x250 fs/super.c:878
 quotactl_block fs/quota/quota.c:890 [inline]
 __do_sys_quotactl fs/quota/quota.c:954 [inline]
 __se_sys_quotactl+0x490/0x770 fs/quota/quota.c:916
 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: 0033:0x7f217f27cf69
RSP: 002b:00007f21800150c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f217f3b4050 RCX: 00007f217f27cf69
RDX: 0000000000000000 RSI: 00000000200000c0 RDI: ffffffff80000801
RBP: 00007f217f2da6fe R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020000100 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f217f3b4050 R15: 00007ffc7abf5cf8
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d12ae50 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d12b650 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by khungtaskd/27:
 #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494
2 locks held by getty/3309:
 #0: ffff88802893d098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188
1 lock held by syz-fuzzer/3562:
2 locks held by kworker/0:10/4967:
 #0: ffff888012472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000377fd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
1 lock held by syz-executor.4/10102:
 #0: ffff88807a4500e0 (&type->s_umount_key#111){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362
2 locks held by kworker/0:1/14069:
 #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc900038cfd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
3 locks held by kworker/0:8/14073:
 #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000454fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8d130278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 #2: ffffffff8d130278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962
3 locks held by kworker/1:3/14268:
 #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000363fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e29b028 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
1 lock held by syz-executor.3/17303:
 #0: ffffffff8e29b028 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8e29b028 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3489
1 lock held by syz-executor.2/17369:
 #0: ffff8880616a40e0 (&type->s_umount_key#111){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362
3 locks held by kworker/0:5/21008:
 #0: ffff888027f8ed38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc9000406fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e

Crashes (20):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/06 22:56 linux-6.1.y 88690811da69 121701b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/06/06 22:54 linux-6.1.y 88690811da69 121701b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/05/25 00:04 linux-6.1.y 4078fa637fcd a10a183e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/05/24 06:23 linux-6.1.y 4078fa637fcd 8f98448e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/05/24 06:22 linux-6.1.y 4078fa637fcd 8f98448e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/05/24 06:20 linux-6.1.y 4078fa637fcd 8f98448e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/05/05 21:41 linux-6.1.y 909ba1f1b414 610f2a54 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/05/05 21:10 linux-6.1.y 909ba1f1b414 610f2a54 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/05/05 15:56 linux-6.1.y 909ba1f1b414 610f2a54 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/04/14 03:09 linux-6.1.y cd5d98c0556c c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/04/10 06:45 linux-6.1.y 347385861c50 171ec371 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/04/09 06:47 linux-6.1.y 347385861c50 f3234354 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/04/08 06:50 linux-6.1.y 347385861c50 ca620dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/04/07 07:46 linux-6.1.y 347385861c50 ca620dd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/04/01 18:38 linux-6.1.y e5cd595e23c1 6baf5069 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/03/19 14:20 linux-6.1.y d7543167affd e104824c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2023/11/20 11:18 linux-6.1.y fb2635ac69ab cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in user_get_super
2024/05/05 16:14 linux-6.1.y 909ba1f1b414 610f2a54 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: task hung in user_get_super
2024/05/04 13:43 linux-6.1.y 909ba1f1b414 610f2a54 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: task hung in user_get_super
2023/12/30 05:13 linux-6.1.y 4aa6747d9352 fb427a07 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: task hung in user_get_super
* Struck through repros no longer work on HEAD.