syzbot


INFO: task hung in chmod_common

Status: auto-closed as invalid on 2019/07/28 15:36
Reported-by: syzbot+99c6c3ad163f238db13a@syzkaller.appspotmail.com
First crash: 2096d, last: 1905d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in chmod_common (4) exfat 2 164d 211d 0/26 auto-obsoleted due to no activity on 2024/02/03 21:30
upstream INFO: task hung in chmod_common (2) fs 2 1184d 1184d 0/26 auto-closed as invalid on 2021/04/20 00:40
upstream INFO: task hung in chmod_common (3) arm 1 433d 433d 0/26 auto-obsoleted due to no activity on 2023/05/10 13:01
upstream INFO: task hung in chmod_common fs 21 2002d 2103d 0/26 closed as invalid on 2018/12/31 08:00

Sample crash report:
IPv6: syzkaller1: Disabled Multicast RS
INFO: task syz-executor3:22766 blocked for more than 140 seconds.
      Not tainted 4.9.153+ #18
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D29880 22766  13499 0x00000000
 ffff88019e4c5f00 0000000000000000 ffff8801db621000 ffffffff8302d180
 ffff8801db621018 ffff8801a262fab0 ffffffff82806016 dffffc0000000000
 ffff8801a262fa88 ffffffff81206e71 00ffffff8281115f ffff8801db6218f0
Call Trace:
 [<ffffffff828075a2>] schedule+0x92/0x1c0 kernel/sched/core.c:3553
 [<ffffffff828113c3>] __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:526 [inline]
 [<ffffffff828113c3>] rwsem_down_write_failed+0x3a3/0x750 kernel/locking/rwsem-xadd.c:555
 [<ffffffff81b78c47>] call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:105
 [<ffffffff8281016c>] __down_write arch/x86/include/asm/rwsem.h:125 [inline]
 [<ffffffff8281016c>] down_write+0x5c/0xa0 kernel/locking/rwsem.c:54
 [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
 [<ffffffff81506e09>] SYSC_fchmodat fs/open.c:582 [inline]
 [<ffffffff81506e09>] SyS_fchmodat+0xb9/0x150 fs/open.c:574
 [<ffffffff81506ec2>] SYSC_chmod fs/open.c:594 [inline]
 [<ffffffff81506ec2>] SyS_chmod+0x22/0x30 fs/open.c:592
 [<ffffffff810056bd>] do_syscall_64+0x1ad/0x570 arch/x86/entry/common.c:285
 [<ffffffff82816293>] 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: [<ffffffff8131b99b>] check_hung_uninterruptible_tasks kernel/hung_task.c:168 [inline]
 #0:  (rcu_read_lock){......}, at: [<ffffffff8131b99b>] watchdog+0x11b/0xa40 kernel/hung_task.c:239
 #1:  (tasklist_lock){.+.?..}, at: [<ffffffff813fe87b>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4336
2 locks held by rs:main Q:Reg/1894:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8156ef78>] __fdget_pos+0xa8/0xd0 fs/file.c:781
 #1:  (sb_writers#4){.+.+.+}, at: [<ffffffff8150cc49>] file_start_write include/linux/fs.h:2642 [inline]
 #1:  (sb_writers#4){.+.+.+}, at: [<ffffffff8150cc49>] vfs_write+0x3e9/0x520 fs/read_write.c:556
1 lock held by rsyslogd/1896:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<ffffffff8156ef78>] __fdget_pos+0xa8/0xd0 fs/file.c:781
2 locks held by getty/2024:
 #0:  (&tty->ldisc_sem){++++++}, at: [<ffffffff82814393>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:377
 #1:  (&ldata->atomic_read_lock){+.+...}, at: [<ffffffff81d3943e>] n_tty_read+0x1fe/0x1820 drivers/tty/n_tty.c:2156
2 locks held by syz-executor3/21370:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
2 locks held by syz-executor3/22529:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
2 locks held by syz-executor3/22579:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
2 locks held by syz-executor3/22733:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
2 locks held by syz-executor3/22766:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
2 locks held by syz-executor3/23032:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
2 locks held by syz-executor3/23155:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
2 locks held by syz-executor3/23320:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81587529>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81587529>] vfs_removexattr+0x79/0x1b0 fs/xattr.c:392
2 locks held by syz-executor3/23412:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
2 locks held by syz-executor3/23923:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
2 locks held by syz-executor3/24204:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
2 locks held by syz-executor3/24562:
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] sb_start_write include/linux/fs.h:1575 [inline]
 #0:  (sb_writers#13){.+.+.+}, at: [<ffffffff8157790f>] mnt_want_write+0x3f/0xb0 fs/namespace.c:391
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] inode_lock include/linux/fs.h:768 [inline]
 #1:  (&type->i_mutex_dir_key#7){++++++}, at: [<ffffffff81503427>] chmod_common+0x187/0x460 fs/open.c:543
1 lock held by syz-executor0/26573:
 #0:  (&pipe->mutex/1){+.+.+.}, at: [<ffffffff8152874e>] __pipe_lock fs/pipe.c:87 [inline]
 #0:  (&pipe->mutex/1){+.+.+.}, at: [<ffffffff8152874e>] pipe_release+0x4e/0x250 fs/pipe.c:568
1 lock held by syz-executor0/26595:
 #0:  (&pipe->mutex/1){+.+.+.}, at: [<ffffffff81525863>] pipe_lock_nested fs/pipe.c:66 [inline]
 #0:  (&pipe->mutex/1){+.+.+.}, at: [<ffffffff81525863>] pipe_lock+0x63/0x80 fs/pipe.c:74
1 lock held by syz-executor0/26610:
 #0:  (&pipe->mutex/1){+.+.+.}, at: [<ffffffff81525863>] pipe_lock_nested fs/pipe.c:66 [inline]
 #0:  (&pipe->mutex/1){+.+.+.}, at: [<ffffffff81525863>] pipe_lock+0x63/0x80 fs/pipe.c:74

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

NMI backtrace for cpu 0
CPU: 0 PID: 24 Comm: khungtaskd Not tainted 4.9.153+ #18
 ffff8801d9907cd0 ffffffff81b47491 0000000000000000 0000000000000000
 0000000000000000 ffffffff81097301 00000000003ffdec ffff8801d9907d08
 ffffffff81b5271c 0000000000000000 0000000000000000 0000000000000000
Call Trace:
 [<ffffffff81b47491>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81b47491>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<ffffffff81b5271c>] nmi_cpu_backtrace.cold+0x47/0x87 lib/nmi_backtrace.c:99
 [<ffffffff81b526a4>] nmi_trigger_cpumask_backtrace+0x124/0x155 lib/nmi_backtrace.c:60
 [<ffffffff81097494>] arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:37
 [<ffffffff8131be77>] trigger_all_cpu_backtrace include/linux/nmi.h:58 [inline]
 [<ffffffff8131be77>] check_hung_task kernel/hung_task.c:125 [inline]
 [<ffffffff8131be77>] check_hung_uninterruptible_tasks kernel/hung_task.c:182 [inline]
 [<ffffffff8131be77>] watchdog+0x5f7/0xa40 kernel/hung_task.c:239
 [<ffffffff81141e18>] kthread+0x278/0x310 kernel/kthread.c:211
 [<ffffffff8281645c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff82814ea2

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/01/29 15:35 https://android.googlesource.com/kernel/common android-4.9 fe0eb27ac6e2 aa432daf .config console log report ci-android-49-kasan-gce-root
2018/08/12 05:12 https://android.googlesource.com/kernel/common android-4.9 9dc978d43ec7 7a88b141 .config console log report ci-android-49-kasan-gce-root
2018/08/05 15:49 https://android.googlesource.com/kernel/common android-4.9 8b21e85d919c 1beb8136 .config console log report ci-android-49-kasan-gce-root
2018/08/04 17:31 https://android.googlesource.com/kernel/common android-4.9 8b21e85d919c 3476a2df .config console log report ci-android-49-kasan-gce-root
2018/08/04 03:10 https://android.googlesource.com/kernel/common android-4.9 8b21e85d919c df7f6947 .config console log report ci-android-49-kasan-gce-root
2018/08/04 02:46 https://android.googlesource.com/kernel/common android-4.9 8b21e85d919c df7f6947 .config console log report ci-android-49-kasan-gce-root
2018/08/02 04:29 https://android.googlesource.com/kernel/common android-4.9 0137ea2134c0 0a7cf4ec .config console log report ci-android-49-kasan-gce-root
2018/08/01 04:45 https://android.googlesource.com/kernel/common android-4.9 90e7a9002952 1477993e .config console log report ci-android-49-kasan-gce-root
2018/07/22 10:03 https://android.googlesource.com/kernel/common android-4.9 47bbcd6bf8f9 8cc079c3 .config console log report ci-android-49-kasan-gce-root
* Struck through repros no longer work on HEAD.