syzbot

INFO: task kworker/u4:6:4461 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:6    state:D stack:26256 pid: 4461 ppid:     2 flags:0x00004000
Workqueue: events_unbound quota_release_workfn
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2093
 do_wait_for_common+0x2a2/0x450 kernel/sched/completion.c:85
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x48/0x60 kernel/sched/completion.c:138
 __synchronize_srcu+0x2bb/0x350 kernel/rcu/srcutree.c:930
 quota_release_workfn+0x106/0x610 fs/quota/dquot.c:828
 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
INFO: task syz.3.20:4465 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.20        state:D stack:21656 pid: 4465 ppid:  4308 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit_lock+0xbc/0x1a0 kernel/sched/wait_bit.c:90
 out_of_line_wait_on_bit_lock+0x138/0x190 kernel/sched/wait_bit.c:117
 lock_buffer include/linux/buffer_head.h:402 [inline]
 ext4_quota_write+0x36d/0x580 fs/ext4/super.c:6636
 qtree_write_dquot+0x203/0x4b0 fs/quota/quota_tree.c:422
 v2_write_dquot+0x108/0x190 fs/quota/quota_v2.c:358
 dquot_commit+0x34b/0x410 fs/quota/dquot.c:514
 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6210
 mark_dquot_dirty fs/quota/dquot.c:372 [inline]
 mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412
 dquot_alloc_inode+0x717/0x9c0 fs/quota/dquot.c:1801
 ext4_xattr_inode_alloc_quota fs/ext4/xattr.c:866 [inline]
 ext4_xattr_set_entry+0xfb2/0x3ea0 fs/ext4/xattr.c:1669
 ext4_xattr_block_set+0x4fd/0x2d20 fs/ext4/xattr.c:1924
 ext4_xattr_set_handle+0xbc4/0x12b0 fs/ext4/xattr.c:2407
 ext4_xattr_set+0x242/0x320 fs/ext4/xattr.c:2508
 __vfs_setxattr+0x3e0/0x420 fs/xattr.c:182
 __vfs_setxattr_noperm+0x129/0x5e0 fs/xattr.c:216
 vfs_setxattr+0x167/0x2e0 fs/xattr.c:303
 do_setxattr fs/xattr.c:588 [inline]
 setxattr+0x36c/0x390 fs/xattr.c:611
 path_setxattr+0x147/0x290 fs/xattr.c:630
 __do_sys_setxattr fs/xattr.c:646 [inline]
 __se_sys_setxattr fs/xattr.c:642 [inline]
 __x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:642
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6e2662b799
RSP: 002b:00007ffe6c2b4a38 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f6e268a4fa0 RCX: 00007f6e2662b799
RDX: 0000200000000380 RSI: 0000200000000340 RDI: 00002000000002c0
RBP: 00007f6e266c1bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000ffed R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6e268a4fac R14: 00007f6e268a4fa0 R15: 00007f6e268a4fa0
 </TASK>
INFO: task syz.0.17:4469 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D stack:21840 pid: 4469 ppid:  4299 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit_lock+0xbc/0x1a0 kernel/sched/wait_bit.c:90
 out_of_line_wait_on_bit_lock+0x138/0x190 kernel/sched/wait_bit.c:117
 lock_buffer include/linux/buffer_head.h:402 [inline]
 ext4_quota_write+0x36d/0x580 fs/ext4/super.c:6636
 qtree_write_dquot+0x203/0x4b0 fs/quota/quota_tree.c:422
 v2_write_dquot+0x108/0x190 fs/quota/quota_v2.c:358
 dquot_commit+0x34b/0x410 fs/quota/dquot.c:514
 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6210
 mark_dquot_dirty fs/quota/dquot.c:372 [inline]
 mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412
 dquot_alloc_inode+0x717/0x9c0 fs/quota/dquot.c:1801
 ext4_xattr_inode_alloc_quota fs/ext4/xattr.c:866 [inline]
 ext4_xattr_set_entry+0xfb2/0x3ea0 fs/ext4/xattr.c:1669
 ext4_xattr_block_set+0x4fd/0x2d20 fs/ext4/xattr.c:1924
 ext4_xattr_set_handle+0xbc4/0x12b0 fs/ext4/xattr.c:2407
 ext4_xattr_set+0x242/0x320 fs/ext4/xattr.c:2508
 __vfs_setxattr+0x3e0/0x420 fs/xattr.c:182
 __vfs_setxattr_noperm+0x129/0x5e0 fs/xattr.c:216
 vfs_setxattr+0x167/0x2e0 fs/xattr.c:303
 do_setxattr fs/xattr.c:588 [inline]
 setxattr+0x36c/0x390 fs/xattr.c:611
 path_setxattr+0x147/0x290 fs/xattr.c:630
 __do_sys_setxattr fs/xattr.c:646 [inline]
 __se_sys_setxattr fs/xattr.c:642 [inline]
 __x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:642
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7faf10a6a799
RSP: 002b:00007ffc20b6d8c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007faf10ce3fa0 RCX: 00007faf10a6a799
RDX: 0000200000000380 RSI: 0000200000000340 RDI: 00002000000002c0
RBP: 00007faf10b00bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000ffed R11: 0000000000000246 R12: 0000000000000000
R13: 00007faf10ce3fac R14: 00007faf10ce3fa0 R15: 00007faf10ce3fa0
 </TASK>
INFO: task syz.4.21:4473 blocked for more than 148 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.21        state:D stack:21840 pid: 4473 ppid:  4311 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit_lock+0xbc/0x1a0 kernel/sched/wait_bit.c:90
 out_of_line_wait_on_bit_lock+0x138/0x190 kernel/sched/wait_bit.c:117
 lock_buffer include/linux/buffer_head.h:402 [inline]
 ext4_quota_write+0x36d/0x580 fs/ext4/super.c:6636
 qtree_write_dquot+0x203/0x4b0 fs/quota/quota_tree.c:422
 v2_write_dquot+0x108/0x190 fs/quota/quota_v2.c:358
 dquot_commit+0x34b/0x410 fs/quota/dquot.c:514
 ext4_write_dquot+0x1f0/0x360 fs/ext4/super.c:6210
 mark_dquot_dirty fs/quota/dquot.c:372 [inline]
 mark_all_dquot_dirty+0xf9/0x400 fs/quota/dquot.c:412
 dquot_alloc_inode+0x717/0x9c0 fs/quota/dquot.c:1801
 ext4_xattr_inode_alloc_quota fs/ext4/xattr.c:866 [inline]
 ext4_xattr_set_entry+0xfb2/0x3ea0 fs/ext4/xattr.c:1669
 ext4_xattr_block_set+0x4fd/0x2d20 fs/ext4/xattr.c:1924
 ext4_xattr_set_handle+0xbc4/0x12b0 fs/ext4/xattr.c:2407
 ext4_xattr_set+0x242/0x320 fs/ext4/xattr.c:2508
 __vfs_setxattr+0x3e0/0x420 fs/xattr.c:182
 __vfs_setxattr_noperm+0x129/0x5e0 fs/xattr.c:216
 vfs_setxattr+0x167/0x2e0 fs/xattr.c:303
 do_setxattr fs/xattr.c:588 [inline]
 setxattr+0x36c/0x390 fs/xattr.c:611
 path_setxattr+0x147/0x290 fs/xattr.c:630
 __do_sys_setxattr fs/xattr.c:646 [inline]
 __se_sys_setxattr fs/xattr.c:642 [inline]
 __x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:642
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f58a9e4e799
RSP: 002b:00007fff2adc9bd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc
RAX: ffffffffffffffda RBX: 00007f58aa0c7fa0 RCX: 00007f58a9e4e799
RDX: 0000200000000380 RSI: 0000200000000340 RDI: 00002000000002c0
RBP: 00007f58a9ee4bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000ffed R11: 0000000000000246 R12: 0000000000000000
R13: 00007f58aa0c7fac R14: 00007f58aa0c7fa0 R15: 00007f58aa0c7fa0
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/0:1/13:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffff8880b9027888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4fe/0x7d0 kernel/sched/psi.c:891
 #2: ffff8880b9029198 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:946
1 lock held by khungtaskd/27:
 #0: ffffffff8c31eaa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:2/154:
 #0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90002027d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8d430c50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589
 #3: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #3: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845
3 locks held by kworker/u4:3/461:
 #0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc900033efd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8d43cb48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
2 locks held by getty/3947:
 #0: ffff88814cc5a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
3 locks held by kworker/1:5/4245:
2 locks held by kworker/u4:6/4461:
 #0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc900034efd00 ((quota_release_work).work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
6 locks held by syz.3.20/4465:
 #0: ffff888023cf0460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386
 #1: ffff888070f27198 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff888070f27198 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: vfs_setxattr+0x140/0x2e0 fs/xattr.c:302
 #2: ffff888070f26e70 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline]
 #2: ffff888070f26e70 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x190/0x12b0 fs/ext4/xattr.c:2322
 #3: ffffffff8c441538 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312
 #4: ffff8880589780a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507
 #5: ffff888023cf0208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x88/0x190 fs/quota/quota_v2.c:356
6 locks held by syz.0.17/4469:
 #0: ffff888023b92460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386
 #1: ffff888070f267a0 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff888070f267a0 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: vfs_setxattr+0x140/0x2e0 fs/xattr.c:302
 #2: ffff888070f26478 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline]
 #2: ffff888070f26478 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x190/0x12b0 fs/ext4/xattr.c:2322
 #3: ffffffff8c441538 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312
 #4: ffff8880589a60a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507
 #5: ffff888023b92208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x88/0x190 fs/quota/quota_v2.c:356
6 locks held by syz.4.21/4473:
 #0: ffff8880252be460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386
 #1: ffff888058a335c8 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff888058a335c8 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: vfs_setxattr+0x140/0x2e0 fs/xattr.c:302
 #2: ffff888058a332a0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline]
 #2: ffff888058a332a0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x190/0x12b0 fs/ext4/xattr.c:2322
 #3: ffffffff8c441538 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312
 #4: ffff8880589785e8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507
 #5: ffff8880252be208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x88/0x190 fs/quota/quota_v2.c:356
6 locks held by syz.2.19/4476:
 #0: ffff8880285d8460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386
 #1: ffff888058a867a0 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff888058a867a0 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: vfs_setxattr+0x140/0x2e0 fs/xattr.c:302
 #2: ffff888058a86478 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline]
 #2: ffff888058a86478 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x190/0x12b0 fs/ext4/xattr.c:2322
 #3: ffffffff8c441538 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312
 #4: ffff8880589a6428 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507
 #5: ffff8880285d8208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x88/0x190 fs/quota/quota_v2.c:356
6 locks held by syz.1.18/4477:
 #0: ffff88805b784460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3d/0x90 fs/namespace.c:386
 #1: ffff888060860de8 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline]
 #1: ffff888060860de8 (&type->i_mutex_dir_key#4){++++}-{3:3}, at: vfs_setxattr+0x140/0x2e0 fs/xattr.c:302
 #2: ffff888060860ac0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:158 [inline]
 #2: ffff888060860ac0 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x190/0x12b0 fs/ext4/xattr.c:2322
 #3: ffffffff8c441538 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:312
 #4: ffff8880589a65e8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x5a/0x410 fs/quota/dquot.c:507