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INFO: task hung in __fdget_pos

Status: auto-closed as invalid on 2019/03/20 03:41
First crash: 2168d, last: 2038d
Similar bugs (9)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in __fdget_pos kernfs 1 2216d 2216d 0/26 closed as invalid on 2018/03/27 11:08
android-44 INFO: task hung in __fdget_pos 2 2037d 2049d 0/2 auto-closed as invalid on 2019/03/21 05:21
linux-6.1 INFO: task hung in __fdget_pos 1 194d 194d 0/3 auto-obsoleted due to no activity on 2024/01/16 13:13
upstream INFO: task hung in __fdget_pos (4) fs syz error 86 2d23h 230d 0/26 upstream: reported syz repro on 2023/09/03 04:11
upstream INFO: task hung in __fdget_pos (3) fs 3 923d 941d 0/26 auto-closed as invalid on 2022/01/07 10:38
android-414 INFO: task hung in __fdget_pos 1 1905d 1836d 0/1 auto-closed as invalid on 2019/07/30 11:39
linux-5.15 INFO: task hung in __fdget_pos (2) 1 5d15h 5d15h 0/3 upstream: reported on 2024/04/14 16:46
linux-5.15 INFO: task hung in __fdget_pos 1 385d 385d 0/3 auto-obsoleted due to no activity on 2023/07/29 10:54
upstream INFO: task hung in __fdget_pos (2) fs 36 1929d 2153d 0/26 closed as dup on 2018/10/27 13:29

Sample crash report:
audit: type=1400 audit(1537501083.307:4918): avc:  denied  { net_admin } for  pid=11588 comm="ip" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
audit: type=1400 audit(1537501083.437:4919): avc:  denied  { net_admin } for  pid=11594 comm="ip" capability=12  scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1
INFO: task syz-executor2:11367 blocked for more than 140 seconds.
      Not tainted 4.9.128+ #93
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor2   D30240 11367   2093 0x00000004
 ffff8801ca615f00 ffff8801d1e5e880 ffff8801ca439600 ffff8801d3378000
 ffff8801db721018 ffff8801c938fce8 ffffffff8277ee02 0000000000000000
 ffff8801ca6167b0 ffffed00394c2cf5 00ff8801ca615f00 ffff8801db7218f0
Call Trace:
 [<ffffffff8278032f>] schedule+0x7f/0x1b0 kernel/sched/core.c:3553
 [<ffffffff82780cb3>] schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3586
 [<ffffffff82782936>] __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 [<ffffffff82782936>] mutex_lock_nested+0x326/0x870 kernel/locking/mutex.c:621
 [<ffffffff8154c6fc>] __fdget_pos+0xac/0xd0 fs/file.c:781
 [<ffffffff814ef37e>] fdget_pos include/linux/file.h:66 [inline]
 [<ffffffff814ef37e>] SYSC_write fs/read_write.c:599 [inline]
 [<ffffffff814ef37e>] SyS_write+0x7e/0x1c0 fs/read_write.c:596
 [<ffffffff8100554f>] do_syscall_64+0x19f/0x480 arch/x86/entry/common.c:282
 [<ffffffff8278df13>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb

Showing all locks held in the system:
2 locks held by khungtaskd/24:
 #0:  (rcu_read_lock){......}, at: [<ffffffff8130a0ac>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8130a0ac>] watchdog+0x11c/0xa20 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.+..}, at: [<ffffffff813e71ec>] debug_show_all_locks+0x79/0x218 kernel/locking/lockdep.c:4336
1 lock held by rsyslogd/1900:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8154c6fc>] __fdget_pos+0xac/0xd0 fs/file.c:781
2 locks held by getty/2027:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff8278bfd2>] ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:367
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff81cdee72>] n_tty_read+0x202/0x16e0 drivers/tty/n_tty.c:2142
1 lock held by syz-executor2/7913:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81ccf2a8>] tty_release+0xa88/0xd00 drivers/tty/tty_io.c:1933
1 lock held by syz-executor2/11367:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8154c6fc>] __fdget_pos+0xac/0xd0 fs/file.c:781
3 locks held by syz-executor2/11370:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8154c6fc>] __fdget_pos+0xac/0xd0 fs/file.c:781
 #1:  (sb_writers#3){.+.+.+}, at: [<ffffffff814eb80b>] file_start_write include/linux/fs.h:2640 [inline]
 #1:  (sb_writers#3){.+.+.+}, at: [<ffffffff814eb80b>] vfs_write+0x3eb/0x520 fs/read_write.c:556
 #2:  (sel_mutex){+.+.+.}, at: [<ffffffff819c6fba>] sel_write_load+0xba/0xfa0 security/selinux/selinuxfs.c:498
1 lock held by syz-executor2/11396:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8154c6fc>] __fdget_pos+0xac/0xd0 fs/file.c:781
1 lock held by init/11404:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2125
1 lock held by init/11405:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2125
1 lock held by init/11406:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2125
1 lock held by init/11407:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2125
1 lock held by init/11408:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2125
1 lock held by init/11432:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open_by_driver drivers/tty/tty_io.c:2047 [inline]
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cd36a6>] tty_open+0x476/0xdf0 drivers/tty/tty_io.c:2125
1 lock held by syz-executor5/11696:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cec497>] ptmx_open+0xf7/0x310 drivers/tty/pty.c:753
1 lock held by syz-executor5/11697:
 #0:  (tty_mutex){+.+.+.}, at: [<ffffffff81cec497>] ptmx_open+0xf7/0x310 drivers/tty/pty.c:753

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

NMI backtrace for cpu 1
CPU: 1 PID: 24 Comm: khungtaskd Not tainted 4.9.128+ #93
 ffff8801d9907d08 ffffffff81af2469 0000000000000000 0000000000000001
 0000000000000001 0000000000000001 ffffffff810967d0 ffff8801d9907d40
 ffffffff81afd1c9 0000000000000001 0000000000000000 0000000000000003
Call Trace:
 [<ffffffff81af2469>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81af2469>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81afd1c9>] nmi_cpu_backtrace.cold.0+0x48/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81afd15c>] nmi_trigger_cpumask_backtrace+0x12c/0x151 lib/nmi_backtrace.c:60
 [<ffffffff810968d4>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff8130a63d>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff8130a63d>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8130a63d>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8130a63d>] watchdog+0x6ad/0xa20 kernel/hung_task.c:239
 [<ffffffff8113e00d>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff8278e0dc>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11249 Comm: syz-executor0 Not tainted 4.9.128+ #93
task: ffff8801a7f04740 task.stack: ffff8801ca840000
RIP: 0010:[<ffffffff810053b0>] c [<ffffffff810053b0>] do_syscall_64+0x0/0x480 arch/x86/entry/common.c:249
RSP: 0018:ffff8801ca847f50  EFLAGS: 00000046
RAX: 00000000000000ca RBX: 0000000000000000 RCX: 0000000000457679
RDX: 0000000000000000 RSI: 0000000000000080 RDI: ffff8801ca847f58
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f5b69626700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c42b4fd000 CR3: 00000001cbeed000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffffffff8278df13c 0000000000000000c 00007f5b696269c0c 0000000000a3fb9fc
 000000000072bf0cc 000000000072bf00c 000000000072bf08c 0000000000000246c
 0000000000000000c 0000000000000000c 0000000000000000c ffffffffffffffdac
Call Trace:
Code: cff cff cff c48 c89 cdf ce8 c70 ce8 c4c c00 ce9 c03 cff cff cff c48 c89 cdf ce8 c63 ce8 c4c c00 ce9 c83 cfe cff cff ce8 c59 ce8 c4c c00 ce9 c55 cff cff cff c0f c1f c40 c00 c<55> c48 c89 ce5 c41 c56 c41 c55 c41 c54 c53 c48 c89 cfb c4c c8d c6b c78 c48 c83 cec c

Crashes (22):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/09/21 03:40 https://android.googlesource.com/kernel/common android-4.9 1c57ba4f543b 6cee973c .config console log report ci-android-49-kasan-gce
2018/09/03 17:10 https://android.googlesource.com/kernel/common android-4.9 a06ea261bc2a a4718693 .config console log report ci-android-49-kasan-gce
2018/08/12 04:47 https://android.googlesource.com/kernel/common android-4.9 9dc978d43ec7 7a88b141 .config console log report ci-android-49-kasan-gce-root
2018/08/11 22:17 https://android.googlesource.com/kernel/common android-4.9 9dc978d43ec7 7a88b141 .config console log report ci-android-49-kasan-gce-root
2018/08/11 17:58 https://android.googlesource.com/kernel/common android-4.9 9dc978d43ec7 7a88b141 .config console log report ci-android-49-kasan-gce-root
2018/08/09 12:18 https://android.googlesource.com/kernel/common android-4.9 856452b4f22e 2eeda842 .config console log report ci-android-49-kasan-gce-root
2018/08/07 19:04 https://android.googlesource.com/kernel/common android-4.9 47b77b8d01c4 1beb8136 .config console log report ci-android-49-kasan-gce-root
2018/08/03 06:42 https://android.googlesource.com/kernel/common android-4.9 0137ea2134c0 5b7e23bb .config console log report ci-android-49-kasan-gce-root
2018/07/30 19:25 https://android.googlesource.com/kernel/common android-4.9 990559158c7b 1a381291 .config console log report ci-android-49-kasan-gce-root
2018/07/19 15:07 https://android.googlesource.com/kernel/common android-4.9 47bbcd6bf8f9 49f35839 .config console log report ci-android-49-kasan-gce-root
2018/07/15 06:38 https://android.googlesource.com/kernel/common android-4.9 9e7903954483 92a49505 .config console log report ci-android-49-kasan-gce-root
2018/07/04 07:40 https://android.googlesource.com/kernel/common android-4.9 03c70feafdb2 317fc8ea .config console log report ci-android-49-kasan-gce-root
2018/06/21 09:35 https://android.googlesource.com/kernel/common android-4.9 e1815b3eba5b 095ef806 .config console log report ci-android-49-kasan-gce-root
2018/06/12 09:59 https://android.googlesource.com/kernel/common android-4.9 db2c520bb56b 112eec79 .config console log report ci-android-49-kasan-gce-root
2018/06/11 06:59 https://android.googlesource.com/kernel/common android-4.9 db2c520bb56b 866118af .config console log report ci-android-49-kasan-gce-root
2018/06/04 09:26 https://android.googlesource.com/kernel/common android-4.9 d7e64f8022e4 6cbe7c26 .config console log report ci-android-49-kasan-gce-root
2018/06/03 09:01 https://android.googlesource.com/kernel/common android-4.9 d7e64f8022e4 2f93b54f .config console log report ci-android-49-kasan-gce-root
2018/05/30 17:19 https://android.googlesource.com/kernel/common android-4.9 7fd40752c316 2f93b54f .config console log report ci-android-49-kasan-gce-root
2018/05/26 15:58 https://android.googlesource.com/kernel/common android-4.9 0cecdf831513 f48c20b8 .config console log report ci-android-49-kasan-gce-root
2018/05/22 21:06 https://android.googlesource.com/kernel/common android-4.9 d4e8148e26ac f48c20b8 .config console log report ci-android-49-kasan-gce-root
2018/05/22 07:25 https://android.googlesource.com/kernel/common android-4.9 aef17a58e8ca f48c20b8 .config console log report ci-android-49-kasan-gce-root
2018/05/13 10:21 https://android.googlesource.com/kernel/common android-4.9 c2f9bce9fee8 c05b619d .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.