syzbot


INFO: task hung in ext4_quota_write (2)

Status: upstream: reported on 2024/05/03 23:59
Reported-by: syzbot+871df0871a38b9bf3ace@syzkaller.appspotmail.com
First crash: 46d, last: 46d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 INFO: task hung in ext4_quota_write origin:upstream missing-backport C 9 17d 175d 0/3 upstream: reported C repro on 2023/12/27 13:51
upstream INFO: task hung in ext4_quota_write ext4 C inconclusive 22 65d 170d 26/27 fixed on 2024/06/05 13:52
linux-5.15 INFO: task hung in ext4_quota_write 2 175d 175d 0/3 auto-obsoleted due to no activity on 2024/04/05 13:59

Sample crash report:
INFO: task syz-executor.3:4381 blocked for more than 143 seconds.
      Not tainted 5.15.158-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:    0 pid: 4381 ppid:  3999 flags:0x00000005
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6376
 schedule+0x11c/0x1c8 kernel/sched/core.c:6459
 io_schedule+0x8c/0x194 kernel/sched/core.c:8484
 bit_wait_io+0x1c/0xac kernel/sched/wait_bit.c:209
 __wait_on_bit_lock+0xcc/0x1f0 kernel/sched/wait_bit.c:90
 out_of_line_wait_on_bit_lock+0x194/0x21c kernel/sched/wait_bit.c:117
 wait_on_bit_lock_io include/linux/wait_bit.h:208 [inline]
 __lock_buffer+0x80/0xc0 fs/buffer.c:69
 lock_buffer include/linux/buffer_head.h:402 [inline]
 ext4_quota_write+0x378/0x564 fs/ext4/super.c:6581
 qtree_write_dquot+0x1dc/0x488 fs/quota/quota_tree.c:422
 v2_write_dquot+0xf4/0x188 fs/quota/quota_v2.c:358
 dquot_commit+0x14c/0x240 fs/quota/dquot.c:514
 ext4_write_dquot+0x1b4/0x314 fs/ext4/super.c:6172
 ext4_mark_dquot_dirty+0xe8/0x140 fs/ext4/super.c:6232
 mark_dquot_dirty fs/quota/dquot.c:372 [inline]
 mark_all_dquot_dirty+0x108/0x424 fs/quota/dquot.c:412
 dquot_alloc_inode+0x6cc/0xdb0 fs/quota/dquot.c:1800
 ext4_xattr_inode_alloc_quota fs/ext4/xattr.c:883 [inline]
 ext4_xattr_set_entry+0x958/0x3094 fs/ext4/xattr.c:1665
 ext4_xattr_block_set+0x55c/0x2d1c fs/ext4/xattr.c:1920
 ext4_xattr_set_handle+0xb04/0x12d8 fs/ext4/xattr.c:2406
 ext4_xattr_set+0x1dc/0x350 fs/ext4/xattr.c:2507
 ext4_xattr_trusted_set+0x4c/0x64 fs/ext4/xattr_trusted.c:38
 __vfs_setxattr+0x388/0x3a4 fs/xattr.c:182
 __vfs_setxattr_noperm+0x110/0x528 fs/xattr.c:216
 __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:277
 vfs_setxattr+0x1a8/0x344 fs/xattr.c:303
 do_setxattr fs/xattr.c:588 [inline]
 setxattr+0x250/0x2b4 fs/xattr.c:611
 path_setxattr+0x17c/0x258 fs/xattr.c:630
 __do_sys_setxattr fs/xattr.c:646 [inline]
 __se_sys_setxattr fs/xattr.c:642 [inline]
 __arm64_sys_setxattr+0xbc/0xd8 fs/xattr.c:642
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
INFO: task syz-executor.3:4416 blocked for more than 143 seconds.
      Not tainted 5.15.158-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:    0 pid: 4416 ppid:  3999 flags:0x00000005
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6376
 schedule+0x11c/0x1c8 kernel/sched/core.c:6459
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6518
 rwsem_down_read_slowpath+0x5b0/0x988 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x10c/0x398 kernel/locking/rwsem.c:1500
 ext4_xattr_get+0xe0/0x6ac fs/ext4/xattr.c:660
 ext4_xattr_trusted_get+0x40/0x54 fs/ext4/xattr_trusted.c:27
 __vfs_getxattr fs/xattr.c:401 [inline]
 vfs_getxattr+0x59c/0x5d0 fs/xattr.c:434
 getxattr+0x158/0x424 fs/xattr.c:701
 path_getxattr+0x14c/0x218 fs/xattr.c:730
 __do_sys_lgetxattr fs/xattr.c:748 [inline]
 __se_sys_lgetxattr fs/xattr.c:745 [inline]
 __arm64_sys_lgetxattr+0xa0/0xb8 fs/xattr.c:745
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
INFO: task syz-executor.3:4418 blocked for more than 143 seconds.
      Not tainted 5.15.158-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:    0 pid: 4418 ppid:  3999 flags:0x0000000d
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6376
 schedule+0x11c/0x1c8 kernel/sched/core.c:6459
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6518
 __mutex_lock_common+0xba0/0x2154 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
 wait_on_dquot fs/quota/dquot.c:356 [inline]
 dqget+0x5f4/0xcd4 fs/quota/dquot.c:981
 __dquot_initialize+0x344/0xc04 fs/quota/dquot.c:1516
 dquot_initialize fs/quota/dquot.c:1578 [inline]
 dquot_file_open+0x90/0xc8 fs/quota/dquot.c:2220
 ext4_file_open+0x200/0x540 fs/ext4/file.c:876
 do_dentry_open+0x780/0xed8 fs/open.c:826
 vfs_open+0x7c/0x90 fs/open.c:956
 do_open fs/namei.c:3608 [inline]
 path_openat+0x1ea0/0x26cc fs/namei.c:3742
 do_filp_open+0x1a8/0x3b4 fs/namei.c:3769
 do_sys_openat2+0x128/0x3d8 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1280
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
INFO: task syz-executor.3:4424 blocked for more than 143 seconds.
      Not tainted 5.15.158-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:    0 pid: 4424 ppid:  3999 flags:0x00000005
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6376
 schedule+0x11c/0x1c8 kernel/sched/core.c:6459
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6518
 __mutex_lock_common+0xba0/0x2154 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
 wait_on_dquot fs/quota/dquot.c:356 [inline]
 dqget+0x5f4/0xcd4 fs/quota/dquot.c:981
 __dquot_initialize+0x344/0xc04 fs/quota/dquot.c:1516
 dquot_initialize fs/quota/dquot.c:1578 [inline]
 dquot_file_open+0x90/0xc8 fs/quota/dquot.c:2220
 ext4_file_open+0x200/0x540 fs/ext4/file.c:876
 do_dentry_open+0x780/0xed8 fs/open.c:826
 vfs_open+0x7c/0x90 fs/open.c:956
 do_open fs/namei.c:3608 [inline]
 path_openat+0x1ea0/0x26cc fs/namei.c:3742
 do_filp_open+0x1a8/0x3b4 fs/namei.c:3769
 do_sys_openat2+0x128/0x3d8 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1280
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Showing all locks held in the system:
2 locks held by kworker/u4:0/9:
 #0: ffff0000c0029138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff800018957c00 ((quota_release_work).work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
1 lock held by khungtaskd/27:
 #0: ffff800014b114a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311
2 locks held by getty/3734:
 #0: ffff0000d320c098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff800018e132e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158
1 lock held by syz-executor.0/3985:
 #0: ffff0000d49060e0 (&type->s_umount_key#53){++++}-{3:3}, at: deactivate_super+0x100/0x128 fs/super.c:365
1 lock held by syz-executor.2/3986:
 #0: ffff0000d8abe0e0 (&type->s_umount_key#30){++++}-{3:3}, at: deactivate_super+0x100/0x128 fs/super.c:365
6 locks held by syz-executor.3/4381:
 #0: ffff0000c13bc460 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:377
 #1: ffff0000e8eb2bd0 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: inode_lock include/linux/fs.h:789 [inline]
 #1: ffff0000e8eb2bd0 (&type->i_mutex_dir_key#3){++++}-{3:3}, at: vfs_setxattr+0x17c/0x344 fs/xattr.c:302
 #2: ffff0000e8eb28a8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_write_lock_xattr fs/ext4/xattr.h:155 [inline]
 #2: ffff0000e8eb28a8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_set_handle+0x1e0/0x12d8 fs/ext4/xattr.c:2321
 #3: ffff800014c289f8 (dquot_srcu){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:311
 #4: ffff0000deea00a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dquot_commit+0x54/0x240 fs/quota/dquot.c:507
 #5: ffff0000c13bc208 (&s->s_dquot.dqio_sem){++++}-{3:3}, at: v2_write_dquot+0x84/0x188 fs/quota/quota_v2.c:356
1 lock held by syz-executor.3/4416:
 #0: ffff0000e8eb28a8 (&ei->xattr_sem){++++}-{3:3}, at: ext4_xattr_get+0xe0/0x6ac fs/ext4/xattr.c:660
1 lock held by syz-executor.3/4418:
 #0: ffff0000deea00a8 (&dquot->dq_lock){+.+.}-{3:3}, at: wait_on_dquot fs/quota/dquot.c:356 [inline]
 #0: ffff0000deea00a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dqget+0x5f4/0xcd4 fs/quota/dquot.c:981
1 lock held by syz-executor.3/4424:
 #0: ffff0000deea00a8 (&dquot->dq_lock){+.+.}-{3:3}, at: wait_on_dquot fs/quota/dquot.c:356 [inline]
 #0: ffff0000deea00a8 (&dquot->dq_lock){+.+.}-{3:3}, at: dqget+0x5f4/0xcd4 fs/quota/dquot.c:981
3 locks held by kworker/1:15/4955:

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


Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/03 23:58 linux-5.15.y 284087d4f7d5 dd26401e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: task hung in ext4_quota_write
* Struck through repros no longer work on HEAD.