syzbot


INFO: task hung in iterate_supers

Status: auto-closed as invalid on 2021/04/29 12:11
Reported-by: syzbot+f9b2878f3e8b8648e10a@syzkaller.appspotmail.com
First crash: 1169d, last: 554d
similar bugs (7):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-414 INFO: task hung in iterate_supers 1 1346d 1184d 0/1 auto-closed as invalid on 2019/04/28 09:45
linux-4.19 INFO: task hung in iterate_supers (2) 1 756d 756d 0/1 auto-closed as invalid on 2020/10/09 12:15
upstream INFO: task hung in iterate_supers C error 58 71d 1458d 0/22 upstream: reported C repro on 2018/07/10 10:30
linux-4.19 INFO: task hung in iterate_supers 7 888d 1076d 0/1 auto-closed as invalid on 2020/05/29 21:42
linux-4.19 INFO: task hung in iterate_supers (3) 24 34d 564d 0/1 upstream: reported on 2020/12/20 03:38
android-49 INFO: task hung in iterate_supers 19 1408d 1508d 0/3 auto-closed as invalid on 2019/02/25 14:49
android-414 INFO: task hung in iterate_supers (2) 1 1165d 1165d 0/1 auto-closed as invalid on 2019/10/25 08:49

Sample crash report:
ldm_parse_privhead(): Cannot find PRIVHEAD structure. LDM database is corrupt. Aborting.
ldm_validate_privheads(): Cannot find PRIVHEAD 1.
 loop3: p2 < > p4
loop3: p4 size 2097152 extends beyond EOD, truncated
INFO: task syz-executor.3:14255 blocked for more than 140 seconds.
      Not tainted 4.14.213-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D28944 14255   8008 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1e6/0x350 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 down_read+0x44/0x80 kernel/locking/rwsem.c:26
 iterate_supers+0xda/0x490 fs/super.c:611
 sys_sync+0x78/0x130 fs/sync.c:113
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45e299
RSP: 002b:00007ffb7d50cc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00000000004cd53c RCX: 000000000045e299
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 000000000119bf80 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c
R13: 00007ffccc38d80f R14: 00007ffb7d50d9c0 R15: 000000000119bf8c
INFO: task syz-executor.3:14287 blocked for more than 140 seconds.
      Not tainted 4.14.213-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D29728 14287   8008 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1e6/0x350 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x14/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 down_read+0x44/0x80 kernel/locking/rwsem.c:26
 iterate_supers+0xda/0x490 fs/super.c:611
 sys_sync+0x78/0x130 fs/sync.c:113
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x45e299
RSP: 002b:00007ffb7d4cac68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00000000004cd53c RCX: 000000000045e299
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 000000000119c0d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119c0dc
R13: 00007ffccc38d80f R14: 00007ffb7d4cb9c0 R15: 000000000119c0dc

Showing all locks held in the system:
1 lock held by khungtaskd/1509:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff81430dd4>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
2 locks held by agetty/7700:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff835e4e32>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff835da183>] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156
1 lock held by syz-executor.3/14255:
 #0:  (&type->s_umount_key#95){++++}, at: [<ffffffff8189b14a>] iterate_supers+0xda/0x490 fs/super.c:611
1 lock held by syz-executor.3/14287:
 #0:  (&type->s_umount_key#95){++++}, at: [<ffffffff8189b14a>] iterate_supers+0xda/0x490 fs/super.c:611

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

NMI backtrace for cpu 1
CPU: 1 PID: 1509 Comm: khungtaskd Not tainted 4.14.213-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x283 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x17f lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 25 Comm: kworker/u4:2 Not tainted 4.14.213-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
task: ffff8880b5636680 task.stack: ffff8880b5640000
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:23 [inline]
RIP: 0010:check_preemption_disabled+0x1d/0x240 lib/smp_processor_id.c:16
RSP: 0018:ffff8880b5647c00 EFLAGS: 00000297
RAX: ffff8880b5636680 RBX: 0000000000000000 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff87ccd1c0 RDI: ffffffff87ccd200
RBP: ffffffff87ccd200 R08: 0000000000000000 R09: 0000000000020012
R10: ffff8880b5636f80 R11: ffff8880b5636680 R12: 0000000000000000
R13: ffffffff87ccd1c0 R14: ffff888059dd5680 R15: ffff888059dd5718
FS:  0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f05e901f018 CR3: 00000000a1cb9000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:360 [inline]
 rcu_is_watching+0x11/0xb0 kernel/rcu/tree.c:1130
 rcu_read_unlock include/linux/rcupdate.h:681 [inline]
 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:943 [inline]
 batadv_iv_ogm_schedule_buff+0x84d/0xf80 net/batman-adv/bat_iv_ogm.c:997
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:1041 [inline]
 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:1034 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x500/0x6f0 net/batman-adv/bat_iv_ogm.c:1859
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: fd ff ff 90 90 90 90 90 90 90 90 90 90 90 41 57 41 56 41 55 49 89 f5 41 54 55 48 89 fd 53 e8 0b 67 35 fe 65 44 8b 25 93 a8 df 7c <65> 8b 05 6c 06 e0 7c a9 ff ff ff 7f 74 18 e8 f0 66 35 fe e8 eb 

Crashes (16):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2020/12/30 12:10 linux-4.14.y 1752938529c6 0fa352f2 .config log report info
ci2-linux-4-14 2020/09/05 16:04 linux-4.14.y 2f166cdcf8a9 abf9ba4f .config log report
ci2-linux-4-14 2020/06/02 06:39 linux-4.14.y 4f68020fef1c a0331e89 .config log report
ci2-linux-4-14 2020/04/08 05:19 linux-4.14.y 4520f06b03ae db9bcd4b .config log report
ci2-linux-4-14 2020/03/01 13:54 linux-4.14.y 78d697fc93f9 c88c7b75 .config log report
ci2-linux-4-14 2020/02/17 00:28 linux-4.14.y 98db2bf27b9e 1f448cd6 .config log report
ci2-linux-4-14 2019/12/25 02:53 linux-4.14.y e1f7d50ae3a3 be5c2c81 .config log report
ci2-linux-4-14 2019/11/20 05:17 linux-4.14.y 775d01b65b5d 432c7650 .config log report
ci2-linux-4-14 2019/11/19 07:05 linux-4.14.y 775d01b65b5d d5696d51 .config log report
ci2-linux-4-14 2019/09/28 20:26 linux-4.14.y f6e27dbb1afa eb6b9855 .config log report
ci2-linux-4-14 2019/09/28 19:07 linux-4.14.y f6e27dbb1afa eb6b9855 .config log report
ci2-linux-4-14 2019/09/23 05:52 linux-4.14.y f6e27dbb1afa d96e88f3 .config log report
ci2-linux-4-14 2019/08/25 05:50 linux-4.14.y 45f092f9e9cb d21c5d9d .config log report
ci2-linux-4-14 2019/06/26 11:03 linux-4.14.y bc2bccef19ee 4d342240 .config log report
ci2-linux-4-14 2019/06/23 03:41 linux-4.14.y a5758c531177 34bf9440 .config log report
ci2-linux-4-14 2019/04/25 13:12 linux-4.14.y 68d7a45eec10 8e3c52b1 .config log report