syzbot


INFO: task hung in iterate_supers

Status: auto-closed as invalid on 2019/04/28 09:45
Reported-by: syzbot+ae5aa56a7e067a497ede@syzkaller.appspotmail.com
First crash: 2393d, last: 2393d
Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 INFO: task hung in iterate_supers 16 1600d 2215d 0/1 auto-closed as invalid on 2021/04/29 12:11
linux-4.19 INFO: task hung in iterate_supers (2) 1 1802d 1802d 0/1 auto-closed as invalid on 2020/10/09 12:15
upstream INFO: task hung in iterate_supers 9p C error 5713 1h39m 2505d 0/28 upstream: reported C repro on 2018/07/10 10:30
linux-5.15 INFO: task hung in iterate_supers origin:lts-only C 295 1h34m 802d 0/3 upstream: reported C repro on 2023/03/08 18:22
linux-6.1 INFO: task hung in iterate_supers origin:upstream C 282 5d10h 800d 0/3 upstream: reported C repro on 2023/03/10 21:24
linux-4.14 INFO: task hung in iterate_supers (2) 1 814d 814d 0/1 upstream: reported on 2023/02/24 15:59
linux-4.19 INFO: task hung in iterate_supers 7 1935d 2122d 0/1 auto-closed as invalid on 2020/05/29 21:42
linux-4.19 INFO: task hung in iterate_supers (3) vfs reiserfs ntfs syz 378 804d 1611d 0/1 upstream: reported syz repro on 2020/12/20 03:38
android-49 INFO: task hung in iterate_supers 19 2454d 2555d 0/3 auto-closed as invalid on 2019/02/25 14:49
android-414 INFO: task hung in iterate_supers (2) 1 2211d 2211d 0/1 auto-closed as invalid on 2019/10/25 08:49

Sample crash report:
audit: type=1400 audit(2000000206.946:2761): avc:  denied  { map } for  pid=21633 comm="modprobe" path="/bin/kmod" dev="sda1" ino=1440 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=0
audit: type=1400 audit(2000000206.996:2762): avc:  denied  { map } for  pid=21634 comm="blkid" path="/sbin/blkid" dev="sda1" ino=16128 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=0
ip6_tunnel: ip6tnl1 xmit: Local address not yet configured!
INFO: task syz-executor3:21577 blocked for more than 140 seconds.
      Not tainted 4.14.78+ #26
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D28632 21577   1847 0x10000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline]
 rwsem_down_read_failed+0x21a/0x3d0 kernel/locking/rwsem-xadd.c:286
 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+0x45/0xa0 kernel/locking/rwsem.c:26
 iterate_supers+0xd6/0x250 fs/super.c:611
 sys_sync+0x95/0x160 fs/sync.c:113
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x457569
RSP: 002b:00007fc50ded8c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 000000000072bf08 RCX: 0000000000457569
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc50ded96d4
R13: 00000000004c3105 R14: 00000000004d7fa0 R15: 00000000ffffffff
INFO: task syz-executor3:21618 blocked for more than 140 seconds.
      Not tainted 4.14.78+ #26
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D29992 21618   1847 0x10000004
Call Trace:
 schedule+0x7f/0x1b0 kernel/sched/core.c:3490
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:269 [inline]
 rwsem_down_read_failed+0x21a/0x3d0 kernel/locking/rwsem-xadd.c:286
 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+0x45/0xa0 kernel/locking/rwsem.c:26
 iterate_supers+0xd6/0x250 fs/super.c:611
 sys_sync+0x95/0x160 fs/sync.c:113
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x457569
RSP: 002b:00007fc50de96c78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 000000000072c048 RCX: 0000000000457569
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc50de976d4
R13: 00000000004c3105 R14: 00000000004d7fa0 R15: 00000000ffffffff

Showing all locks held in the system:
1 lock held by khungtaskd/23:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffffa3e02047>] debug_show_all_locks+0x74/0x20f kernel/locking/lockdep.c:4541
1 lock held by rsyslogd/1628:
 #0:  (&f->f_pos_lock){+.+.}, at: [<ffffffffa41bd752>] __fdget_pos+0xa2/0xc0 fs/file.c:768
2 locks held by getty/1756:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffffa492f4c0>] tty_ldisc_ref_wait+0x20/0x80 drivers/tty/tty_ldisc.c:275
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffffa492aa3f>] n_tty_read+0x1ff/0x15e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor5/30967:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffffa492f4c0>] tty_ldisc_ref_wait+0x20/0x80 drivers/tty/tty_ldisc.c:275
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffffa492aa3f>] n_tty_read+0x1ff/0x15e0 drivers/tty/n_tty.c:2142
2 locks held by syz-executor2/31041:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffffa492f4c0>] tty_ldisc_ref_wait+0x20/0x80 drivers/tty/tty_ldisc.c:275
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffffa492aa3f>] n_tty_read+0x1ff/0x15e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor3/21577:
 #0:  (&type->s_umount_key#49){.+.+}, at: [<ffffffffa4163436>] iterate_supers+0xd6/0x250 fs/super.c:611
1 lock held by syz-executor3/21618:
 #0:  (&type->s_umount_key#49){.+.+}, at: [<ffffffffa4163436>] iterate_supers+0xd6/0x250 fs/super.c:611

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

NMI backtrace for cpu 1
CPU: 1 PID: 23 Comm: khungtaskd Not tainted 4.14.78+ #26
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 nmi_cpu_backtrace.cold.0+0x47/0x85 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x121/0x146 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:196 [inline]
 watchdog+0x574/0xa70 kernel/hung_task.c:252
 kthread+0x348/0x420 kernel/kthread.c:232
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 21254 Comm: syz-executor5 Not tainted 4.14.78+ #26
task: ffff88019fe4af00 task.stack: ffff8801ceff8000
RIP: 0033:0x4015bb
RSP: 002b:00007fe5644a0690 EFLAGS: 00000206
RAX: 000000007a6dc6ff RBX: 0000000000000007 RCX: 0000000000457569
RDX: 0000000000457569 RSI: 00007fe5644a06c0 RDI: 0000000000000007
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe5644a16d4
R13: 00000000004c5162 R14: 00000000004d88d0 R15: 00000000ffffffff
FS:  00007fe5644a1700(0000) GS:ffff8801dba00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff1bf147000 CR3: 00000001d4a6c005 CR4: 00000000001606b0
DR0: 0000000020000000 DR1: 0000000020000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/10/30 09:44 android-4.14 4ed22187defd 2f1090da .config console log report ci-android-414-kasan-gce-root
* Struck through repros no longer work on HEAD.