syzbot


INFO: task hung in kernfs_dop_revalidate

Status: auto-closed as invalid on 2019/12/01 15:25
Reported-by: syzbot+4f0307c3e7572274dc8d@syzkaller.appspotmail.com
First crash: 1778d, last: 1778d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in kernfs_dop_revalidate kernfs syz unreliable inconclusive 2 698d 724d 0/27 auto-obsoleted due to no activity on 2022/11/15 03:06
upstream INFO: task hung in kernfs_dop_revalidate (4) kernfs C error 14 1d07h 11d 0/27 upstream: reported C repro on 2024/06/04 12:47
upstream INFO: task hung in kernfs_dop_revalidate (2) kernfs 3 502d 556d 0/27 auto-obsoleted due to no activity on 2023/04/29 22:59
upstream INFO: task hung in kernfs_dop_revalidate (3) kernfs 1 226d 226d 0/27 auto-obsoleted due to no activity on 2024/01/31 18:27

Sample crash report:
[13490]     0 13490    18178     8971      26       4        0             0 syz-executor.4
[13731]     0 13731    18145     8747      25       3        0             0 syz-executor.2
[13736]     0 13736    18244     8753      25       3        0             0 syz-executor.2
INFO: task blkid:26166 blocked for more than 140 seconds.
[13831]     0 13831    18178     8976      26       4        0             0 syz-executor.1
      Not tainted 4.14.135+ #26
[13927]     0 13927    18267     8980      27       4        0             0 syz-executor.1
[14004]     0 14004    18211     8974      27       4        0             0 syz-executor.0
[14043]     0 14043    18211     8975      26       4        0             0 syz-executor.1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D27752 26166  26151 0x00000000
Call Trace:
[14141]     0 14141    18178     8994      27       4        0             0 syz-executor.5
[14251]     0 14251    18178     8973      26       4        0             0 syz-executor.1
[14263]     0 14263    18145     8746      25       3        0             0 syz-executor.1
[14603]     0 14603    18178     8970      33       4        0             0 syz-executor.4
[14667]     0 14667    18277     8979      26       4        0             0 syz-executor.1
[14690]     0 14690    18145     8762      26       3        0             0 syz-executor.1
[14693]     0 14693    18195     8750      26       3        0             0 syz-executor.1
[14699]     0 14699    18261     8979      27       4        0             0 /selinux/status
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 kernfs_dop_revalidate+0x8d/0x370 fs/kernfs/dir.c:570
 d_revalidate fs/namei.c:799 [inline]
 lookup_fast+0x927/0xea0 fs/namei.c:1658
 walk_component+0xd3/0xbf0 fs/namei.c:1835
[14717]     0 14717    18244     8979      27       4        0             0 syz-executor.0
[14743]     0 14743    18244     8979      27       4        0             0 syz-executor.0
[15034]     0 15034    18244     8996      27       4        0             0 syz-executor.5
[15040]     0 15040    18244     8996      27       4        0             0 syz-executor.5
[15175]     0 15175    18145     8746      25       3        0             0 syz-executor.1
[15253]     0 15253    18211     8750      28       3        0             0 syz-executor.1
 link_path_walk+0x84a/0x1110 fs/namei.c:2168
 path_openat+0x178/0x2be0 fs/namei.c:3596
[15257]     0 15257    18211     8750      32       3        0             0 syz-executor.1
[15310]     0 15310    18178     8973      26       4        0             0 syz-executor.1
 do_filp_open+0x1a1/0x280 fs/namei.c:3631
 do_sys_open+0x2ca/0x590 fs/open.c:1096
[15312]     0 15312    18178     8749      25       3        0             0 syz-executor.1
[15337]     0 15337    18211     8976      27       4        0             0 syz-executor.1
[15431]     0 15431    18244     8975      26       4        0             0 syz-executor.2
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
INFO: task blkid:26167 blocked for more than 140 seconds.
      Not tainted 4.14.135+ #26
[15515]     0 15515    18178     8970      26       4        0             0 syz-executor.4
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
blkid           D27776 26167  26154 0x00000000
Call Trace:
[15520]     0 15520    18178     8970      26       4        0             0 syz-executor.4
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
[15771]     0 15771    18244     8996      27       4        0             0 syz-executor.5
[15774]     0 15774    18244     8996      27       4        0             0 syz-executor.5
[16051]     0 16051    18145     8968      26       4        0             0 syz-executor.4
[16062]     0 16062    18178     8750      25       3        0             0 syz-executor.1
[16079]     0 16079    18244     8754      25       3        0             0 syz-executor.1
 kernfs_iop_permission+0x4e/0x90 fs/kernfs/inode.c:301
[16126]     0 16126    18142     8747      25       3        0             0 syz-executor.1
 do_inode_permission fs/namei.c:386 [inline]
 __inode_permission2+0x22c/0x2c0 fs/namei.c:428
 inode_permission2+0x2d/0x100 fs/namei.c:485
 may_lookup fs/namei.c:1731 [inline]
 link_path_walk+0x8a6/0x1110 fs/namei.c:2111
 path_lookupat.isra.0+0xde/0x7e0 fs/namei.c:2356
[16134]     0 16134    18175     8756      26       3        0             0 syz-executor.1
[16211]     0 16211    18244     9012      27       4        0             0 syz-executor.5
[16227]     0 16227    18211     8993      26       4        0             0 syz-executor.3
[16253]     0 16253    18211     8993      26       4        0             0 syz-executor.3
[16310]     0 16310    18145     8746      25       3        0             0 syz-executor.1
 filename_lookup+0x1a1/0x3b0 fs/namei.c:2391
[16316]     0 16316    18145     8968      26       4        0             0 syz-executor.4
 SYSC_readlinkat fs/stat.c:394 [inline]
 SyS_readlinkat+0xbe/0x2b0 fs/stat.c:382
[16321]     0 16321    18178     8749      25       3        0             0 syz-executor.1
[16322]     0 16322    18178     8749      25       3        0             0 syz-executor.1
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
[16325]     0 16325    18244     8977      26       4        0             0 syz-executor.1
[16326]     0 16326    18244     8753      25       3        0             0 syz-executor.1
[16345]     0 16345    18178     8793      26       3        0             0 syz-executor.2
INFO: task udevd:26177 blocked for more than 140 seconds.
      Not tainted 4.14.135+ #26
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[16365]     0 16365    18211     9678      27       3        0             0 syz-executor.2
udevd           D25696 26177    190 0x00000000
[16382]     0 16382    18145     8746      26       3        0             0 syz-executor.0
Call Trace:
[16388]     0 16388    18178     8751      26       3        0             0 syz-executor.0
[16399]     0 16399    18178     8972      26       4        0             0 syz-executor.1
[16426]     0 16426    18211     8974      26       4        0             0 syz-executor.1
[16435]     0 16435    18211     8995      26       4        0             0 syz-executor.3
[16480]     0 16480    18145     8989      26       4        0             0 syz-executor.3
[16622]     0 16622    18277     8980      27       4        0             0 syz-executor.4
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
[16653]     0 16653    18145     8737      24       3        0             0 syz-executor.1
[16655]     0 16655    18145     8746      25       3        0             0 syz-executor.1
[16684]     0 16684    18244     8976      26       4        0             0 syz-executor.1
[16752]     0 16752    18178     8748      25       3        0             0 syz-executor.2
[16758]     0 16758    18211     8750      25       3        0             0 syz-executor.2
[16821]     0 16821    18145     8970      27       4        0             0 syz-executor.0
 kernfs_iop_permission+0x4e/0x90 fs/kernfs/inode.c:301
 do_inode_permission fs/namei.c:386 [inline]
 __inode_permission2+0x22c/0x2c0 fs/namei.c:428
[17261]     0 17261    18178     8972      26       4        0             0 syz-executor.2
[17386]     0 17386    18145     8746      25       3        0             0 syz-executor.3
 inode_permission2+0x2d/0x100 fs/namei.c:485
 may_lookup fs/namei.c:1731 [inline]
 link_path_walk+0x8a6/0x1110 fs/namei.c:2111
[17434]     0 17434    18211     8974      27       4        0             0 syz-executor.0
[17829]     0 17829    18145     8747      25       3        0             0 syz-executor.4
[17843]     0 17843    18244     8754      26       3        0             0 syz-executor.4
[17934]     0 17934    18145     8746      25       3        0             0 syz-executor.4
 path_lookupat.isra.0+0xde/0x7e0 fs/namei.c:2356
[17936]     0 17936    18211     8994      26       4        0             0 syz-executor.3
[17954]     0 17954    18178     8991      26       4        0             0 syz-executor.3
 filename_lookup+0x1a1/0x3b0 fs/namei.c:2391
[17977]     0 17977    18211     8975      27       4        0             0 syz-executor.1
[17995]     0 17995    18211     8975      27       4        0             0 syz-executor.1
 SYSC_readlinkat fs/stat.c:394 [inline]
 SyS_readlinkat+0xbe/0x2b0 fs/stat.c:382
[18142]     0 18142    18178     8973      27       4        0             0 syz-executor.0
[18192]     0 18192    18145     8745      25       3        0             0 syz-executor.4
[18195]     0 18195    18211     8974      27       4        0             0 syz-executor.0
[18252]     0 18252    18343     8983      26       4        0             0 syz-executor.2
[18304]     0 18304    18211     8975      26       4        0             0 syz-executor.1
[18330]     0 18330    18244     8975      26       4        0             0 syz-executor.2
[18335]     0 18335    18178     8748      25       3        0             0 syz-executor.1
[18470]     0 18470    18145     8992      27       4        0             0 syz-executor.5
[18480]     0 18480    18178     8972      26       4        0             0 syz-executor.1
[18487]     0 18487    18178     8972      26       4        0             0 syz-executor.1
[18514]     0 18514    18178    13262      33       3        0             0 syz-executor.5
[18539]     0 18539    18209    13322      33       3        0             0 syz-executor.5
[18553]     0 18553    18376     8989      26       4        0             0 syz-executor.1
[18593]     0 18593    18178     8974      26       4        0             0 syz-executor.2
[18639]     0 18639    34662     9018      28       4        0             0 syz-executor.1
[18671]     0 18671    34662     9018      28       4        0             0 syz-executor.1
[18732]     0 18732    18178     8971      26       4        0             0 syz-executor.2
[18827]     0 18827    18178     8981      26       4        0             0 syz-executor.4
[18864]     0 18864    18310     8979      26       4        0             0 syz-executor.2
[18909]     0 18909    18178     8971      26       4        0             0 syz-executor.2
[18915]     0 18915    18244     8976      27       4        0             0 syz-executor.0
[18951]     0 18951    18244     8976      27       4        0             0 syz-executor.0
[19202]     0 19202    18178     8749      25       3        0             0 syz-executor.3
[19206]     0 19206    18211     8751      25       3        0             0 syz-executor.3
[19213]     0 19213    18178     8749      25       3        0             0 syz-executor.1
[19219]     0 19219    18211     8751      25       3        0             0 syz-executor.1
[19351]     0 19351    18145     8967      25       4        0             0 syz-executor.4
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
[19418]     0 19418    18178     8970      27       4        0             0 syz-executor.0
[19528]     0 19528    18178     8990      26       4        0             0 syz-executor.3
INFO: task udevd:26178 blocked for more than 140 seconds.
[19609]     0 19609    18178     8971      26       4        0             0 syz-executor.2
      Not tainted 4.14.135+ #26
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
udevd           D26272 26178    190 0x00000000
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
 kernfs_iop_permission+0x4e/0x90 fs/kernfs/inode.c:301
 do_inode_permission fs/namei.c:386 [inline]
 __inode_permission2+0x22c/0x2c0 fs/namei.c:428
 inode_permission2+0x2d/0x100 fs/namei.c:485
 may_lookup fs/namei.c:1731 [inline]
 link_path_walk+0x8a6/0x1110 fs/namei.c:2111
[19684]     0 19684    18244     8977      26       4        0             0 syz-executor.2
[19701]     0 19701    18244     8976      26       4        0             0 syz-executor.1
[19757]     0 19757    18211     8972      26       4        0             0 syz-executor.4
[19837]     0 19837    18211     8993      27       4        0             0 syz-executor.5
[19840]     0 19840    18178     8990      26       4        0             0 syz-executor.3
[19854]     0 19854    18178     8749      25       3        0             0 syz-executor.3
[19857]     0 19857    18244     8755      25       3        0             0 syz-executor.3
 path_lookupat.isra.0+0xde/0x7e0 fs/namei.c:2356
 filename_lookup+0x1a1/0x3b0 fs/namei.c:2391
 SYSC_readlinkat fs/stat.c:394 [inline]
 SyS_readlinkat+0xbe/0x2b0 fs/stat.c:382
[19895]     0 19895    18244     8974      27       4        0             0 syz-executor.4
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
INFO: task udevd:26180 blocked for more than 140 seconds.
[19952]     0 19952    18145     8736      24       3        0             0 syz-executor.2
      Not tainted 4.14.135+ #26
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
udevd           D28296 26180    190 0x00000000
[19967]     0 19967    18178     8748      25       3        0             0 syz-executor.2
[20015]     0 20015    18178     9004      26       4        0             0 syz-executor.3
[20034]     0 20034    18244     9009      27       4        0             0 syz-executor.3
Call Trace:
[20041]     0 20041    34629     9018      28       4        0             0 syz-executor.1
[20048]     0 20048    18244     8994      26       4        0             0 syz-executor.3
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
[20055]     0 20055    18145     8747      26       3        0             0 syz-executor.5
 kernfs_iop_getattr+0x85/0xd0 fs/kernfs/inode.c:209
 vfs_getattr_nosec+0x107/0x170 fs/stat.c:79
 vfs_getattr+0x3f/0x60 fs/stat.c:116
 vfs_statx+0x100/0x180 fs/stat.c:189
[20061]     0 20061    18178     8753      26       3        0             0 syz-executor.5
[20069]     0 20069    18178     8748      26       3        0             0 syz-executor.0
[20076]     0 20076    34629     9018      28       4        0             0 syz-executor.1
[20078]     0 20078    18211     8750      26       3        0             0 syz-executor.0
 vfs_stat include/linux/fs.h:3085 [inline]
 SYSC_newstat fs/stat.c:337 [inline]
 SyS_newstat+0x96/0x110 fs/stat.c:333
[20080]     0 20080    18244     8994      26       4        0             0 syz-executor.3
[20194]     0 20194    18211     8976      26       4        0             0 syz-executor.1
[20261]     0 20261    18211     8973      26       4        0             0 syz-executor.2
[20328]     0 20328    18145     8746      26       3        0             0 syz-executor.0
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
[20330]     0 20330    18211     8975      27       4        0             0 syz-executor.0
[20331]     0 20331    18178     8749      26       3        0             0 syz-executor.0
[20332]     0 20332    18178     8749      26       3        0             0 syz-executor.0
INFO: task udevd:26181 blocked for more than 140 seconds.
      Not tainted 4.14.135+ #26
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
udevd           D25600 26181    190 0x00000000
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
[20358]     0 20358    18178     8989      26       4        0             0 syz-executor.3
[20410]     0 20410    18178     8971      26       4        0             0 syz-executor.2
[20435]     0 20435    18211     8976      26       4        0             0 syz-executor.1
[20506]     0 20506    18244     8978      26       4        0             0 syz-executor.2
[20510]     0 20510    18178     8750      26       3        0             0 syz-executor.5
[20513]     0 20513    18244     9003      27       4        0             0 syz-executor.5
[20515]     0 20515    18211     8752      26       3        0             0 syz-executor.5
[20522]     0 20522    18244     8752      26       3        0             0 syz-executor.5
[20602]     0 20602    18178     8999      26       4        0             0 syz-executor.3
[20608]     0 20608    18178     8999      26       4        0             0 syz-executor.3
[20616]     0 20616    18178     8974      26       4        0             0 syz-executor.4
[20632]     0 20632    18178     8748      25       3        0             0 syz-executor.1
 kernfs_iop_permission+0x4e/0x90 fs/kernfs/inode.c:301
 do_inode_permission fs/namei.c:386 [inline]
 __inode_permission2+0x22c/0x2c0 fs/namei.c:428
 inode_permission2+0x2d/0x100 fs/namei.c:485
 may_lookup fs/namei.c:1731 [inline]
 link_path_walk+0x8a6/0x1110 fs/namei.c:2111
 path_lookupat.isra.0+0xde/0x7e0 fs/namei.c:2356
[20633]     0 20633    18178     8748      25       3        0             0 syz-executor.1
 filename_lookup+0x1a1/0x3b0 fs/namei.c:2391
 user_path_at include/linux/namei.h:57 [inline]
 vfs_statx+0xe1/0x180 fs/stat.c:185
 vfs_stat include/linux/fs.h:3085 [inline]
 SYSC_newstat fs/stat.c:337 [inline]
 SyS_newstat+0x96/0x110 fs/stat.c:333
[20635]     0 20635    18178     8748      25       3        0             0 syz-executor.1
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
INFO: task udevd:26186 blocked for more than 140 seconds.
[20636]     0 20636    18211     8750      25       3        0             0 syz-executor.1
      Not tainted 4.14.135+ #26
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[20720]     0 20720    18211     8975      26       4        0             0 syz-executor.1
udevd           D28072 26186    190 0x00000000
[20738]     0 20738    18145     8994      27       4        0             0 syz-executor.5
Call Trace:
[20759]     0 20759    18211     8975      27       4        0             0 syz-executor.2
[20796]     0 20796    18178     8992      26       4        0             0 syz-executor.3
[21185]     0 21185    18178     8972      26       4        0             0 syz-executor.1
[21214]     0 21214    18178     8738      24       3        0             0 syz-executor.2
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
[21217]     0 21217    18178     8747      25       3        0             0 syz-executor.2
[21272]     0 21272    18145     8987      26       4        0             0 syz-executor.3
[21302]     0 21302    18178     8975      28       4        0             0 syz-executor.0
 kernfs_iop_permission+0x4e/0x90 fs/kernfs/inode.c:301
[21341]     0 21341    18145     8971      26       4        0             0 syz-executor.1
 do_inode_permission fs/namei.c:386 [inline]
 __inode_permission2+0x22c/0x2c0 fs/namei.c:428
 inode_permission2+0x2d/0x100 fs/namei.c:485
 may_lookup fs/namei.c:1731 [inline]
 link_path_walk+0x8a6/0x1110 fs/namei.c:2111
[21434]     0 21434    18145     8747      25       3        0             0 syz-executor.1
[21438]     0 21438    18211     8751      25       3        0             0 syz-executor.1
[21440]     0 21440    18211     8975      26       4        0             0 syz-executor.1
 path_lookupat.isra.0+0xde/0x7e0 fs/namei.c:2356
[21520]     0 21520    18178     8749      25       3        0             0 syz-executor.4
[21545]     0 21545    18343    10518      30       4        0             0 syz-executor.2
[21560]     0 21560    18178     8972      26       4        0             0 syz-executor.1
 filename_lookup+0x1a1/0x3b0 fs/namei.c:2391
[21594]     0 21594    18211     8974      26       4        0             0 syz-executor.1
 SYSC_readlinkat fs/stat.c:394 [inline]
 SyS_readlinkat+0xbe/0x2b0 fs/stat.c:382
[21611]     0 21611    18178     8972      26       4        0             0 syz-executor.1
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292
[21622]     0 21622    18145     8990      28       4        0             0 syz-executor.3
[21741]     0 21741    18178     8975      26       4        0             0 syz-executor.1
[21771]     0 21771    18145     8736      24       3        0             0 syz-executor.2
INFO: task udevd:26188 blocked for more than 140 seconds.
[21864]     0 21864    18244     8976      26       4        0             0 syz-executor.2
      Not tainted 4.14.135+ #26
[21873]     0 21873    18145     8970      26       4        0             0 syz-executor.4
[21896]     0 21896    18145     8745      25       3        0             0 syz-executor.2
[21983]     0 21983    18145     8988      26       4        0             0 syz-executor.3
[21997]     0 21997    18178     8748      26       3        0             0 syz-executor.0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
udevd           D26976 26188    190 0x00000000
Call Trace:
[21998]     0 21998    18244     8976      27       4        0             0 syz-executor.0
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
[21999]     0 21999    18178     8748      26       3        0             0 syz-executor.0
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556
[22003]     0 22003    18244     8752      26       3        0             0 syz-executor.0
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x595/0x13e0 kernel/locking/mutex.c:893
[22005]     0 22005    18244     8752      26       3        0             0 syz-executor.0
[22144]     0 22144    18244     8976      27       4        0             0 syz-executor.0
 kernfs_dop_revalidate+0x8d/0x370 fs/kernfs/dir.c:570
 d_revalidate fs/namei.c:799 [inline]
 lookup_fast+0x927/0xea0 fs/namei.c:1658
[22146]     0 22146    18145     8747      25       3        0             0 syz-executor.4
 walk_component+0xd3/0xbf0 fs/namei.c:1835
[22147]     0 22147    18211     8975      26       4        0             0 syz-executor.4
[22239]     0 22239    18277     8998      26       4        0             0 syz-executor.3
[22261]     0 22261    18277     8998      26       4        0             0 syz-executor.3
 link_path_walk+0x84a/0x1110 fs/namei.c:2168
[22462]     0 22462    18145     8746      25       3        0             0 syz-executor.3
[22466]     0 22466    18244     9000      26       4        0             0 syz-executor.3
 path_lookupat.isra.0+0xde/0x7e0 fs/namei.c:2356
[22467]     0 22467    18178     8748      25       3        0             0 syz-executor.3
[22470]     0 22470    18211     8750      25       3        0             0 syz-executor.3
 filename_lookup+0x1a1/0x3b0 fs/namei.c:2391
[22475]     0 22475    18244     8752      25       3        0             0 syz-executor.3
[22724]     0 22724    18178    11809      31       4        0             0 syz-executor.4
[22831]     0 22831    18145     8988      26       4        0             0 syz-executor.3
 SYSC_readlinkat fs/stat.c:394 [inline]
 SyS_readlinkat+0xbe/0x2b0 fs/stat.c:382
 do_syscall_64+0x19b/0x520 arch/x86/entry/common.c:292

Showing all locks held in the system:
1 lock held by khungtaskd/23:
 #0:  (tasklist_lock){.+.?}, at: [<00000000dd936af1>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4541
3 locks held by udevd/190:
 #0:  (&dup_mmap_sem){.+.+}, at: [<00000000f4f5b6b9>] dup_mmap kernel/fork.c:609 [inline]
 #0:  (&dup_mmap_sem){.+.+}, at: [<00000000f4f5b6b9>] dup_mm kernel/fork.c:1211 [inline]
 #0:  (&dup_mmap_sem){.+.+}, at: [<00000000f4f5b6b9>] copy_mm kernel/fork.c:1266 [inline]
 #0:  (&dup_mmap_sem){.+.+}, at: [<00000000f4f5b6b9>] copy_process.part.0+0x1fd6/0x68b0 kernel/fork.c:1789
 #1:  (&mm->mmap_sem){++++}, at: [<00000000d4266cac>] dup_mmap kernel/fork.c:610 [inline]
 #1:  (&mm->mmap_sem){++++}, at: [<00000000d4266cac>] dup_mm kernel/fork.c:1211 [inline]
 #1:  (&mm->mmap_sem){++++}, at: [<00000000d4266cac>] copy_mm kernel/fork.c:1266 [inline]
 #1:  (&mm->mmap_sem){++++}, at: [<00000000d4266cac>] copy_process.part.0+0x1ff2/0x68b0 kernel/fork.c:1789
 #2:  (&mm->mmap_sem/1){+.+.}, at: [<00000000b71f412f>] dup_mmap kernel/fork.c:619 [inline]
 #2:  (&mm->mmap_sem/1){+.+.}, at: [<00000000b71f412f>] dup_mm kernel/fork.c:1211 [inline]
 #2:  (&mm->mmap_sem/1){+.+.}, at: [<00000000b71f412f>] copy_mm kernel/fork.c:1266 [inline]
 #2:  (&mm->mmap_sem/1){+.+.}, at: [<00000000b71f412f>] copy_process.part.0+0x203a/0x68b0 kernel/fork.c:1789
1 lock held by rsyslogd/1630:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by cron/1673:
 #0:  (&ei->i_mmap_sem){++++}, at: [<0000000045873517>] ext4_filemap_fault+0x7c/0xb0 fs/ext4/inode.c:6196
2 locks held by getty/1759:
 #0:  (&tty->ldisc_sem){++++}, at: [<000000000aeb5305>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<0000000028fead91>] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156
1 lock held by syz-fuzzer/1781:
 #0:  (&ei->i_mmap_sem){++++}, at: [<0000000045873517>] ext4_filemap_fault+0x7c/0xb0 fs/ext4/inode.c:6196
1 lock held by syz-fuzzer/1791:
 #0:  (&ei->i_mmap_sem){++++}, at: [<0000000045873517>] ext4_filemap_fault+0x7c/0xb0 fs/ext4/inode.c:6196
1 lock held by udevd/3038:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/25935:
 #0:  (
[22853]     0 22853    18177     8993      26       4        0             0 syz-executor.3
&mm->mmap_sem
[22868]     0 22868    18211     8975      26       4        0             0 syz-executor.1
){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/25954:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/25969:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/25971:
 #0:  (&ei->i_mmap_sem){++++}, at: [<0000000045873517>] ext4_filemap_fault+0x7c/0xb0 fs/ext4/inode.c:6196
[23096]     0 23096    18178    13293      32       3        0             0 syz-executor.4
1 lock held by blkid/25975:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/25977:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/25981:
[23108]     0 23108    18178    11757      30       3        0             0 syz-executor.4
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/25978:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/25982:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/25983:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/25984:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/26030:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/26033:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/26034:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/26035:
[23131]     0 23131    18145     8747      25       3        0             0 syz-executor.1
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/26036:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/26037:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/26038:
[23134]     0 23134    18211     8751      25       3        0             0 syz-executor.1
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/26039:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/26040:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/26045:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/26166:
 #0:  (kernfs_mutex){+.+.}, at: [<000000005664d0eb>] kernfs_dop_revalidate+0x8d/0x370 fs/kernfs/dir.c:570
1 lock held by blkid/26167:
 #0:  (kernfs_mutex){+.+.}, at: [<000000005f445f4d>] kernfs_iop_permission+0x4e/0x90 fs/kernfs/inode.c:301
1 lock held by udevd/26168:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by udevd/26170:
[23170]     0 23170    18178     8972      26       4        0             0 syz-executor.4
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/26171:
 #0:  (&ei->i_mmap_sem){++++}, at: [<0000000045873517>] ext4_filemap_fault+0x7c/0xb0 fs/ext4/inode.c:6196
1 lock held by blkid/26172:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/26174:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
1 lock held by blkid/26175:
 #0:  (&mm->mmap_sem){++++}, at: [<000000001951196b>] __do_page_fault+0x282/0xbb0 arch/x86/mm/fault.c:1352
[23171]     0 23171    18178     8972      26       4        0             0 syz-executor.4
1 lock held by udevd/26176:
 #0:  (&ei->i_mmap_sem){++++}, at: [<0000000045873517>] ext4_filemap_fault+0x7c/0xb0 fs/ext4/inode.c:6196
1 lock held by udevd/26177:
 #0:  (kernfs_mutex){+.+.}, at: [<000000005f445f4d>] kernfs_iop_permission+0x4e/0x90 fs/kernfs/inode.c:301
1 lock held by udevd/26178:
 #0:  (kernfs_mutex){+.+.}, at: [<000000005f445f4d>] kernfs_iop_permission+0x4e/0x90 fs/kernfs/inode.c:301
1 lock held by udevd/26180:
 #0:  (kernfs_mutex){+.+.}, at: [<0000000052cdcda2>] kernfs_iop_getattr+0x85/0xd0 fs/kernfs/inode.c:209
1 lock held by udevd/26181:
 #0:  (kernfs_mutex){+.+.}, at: [<000000005f445f4d>] kernfs_iop_permission+0x4e/0x90 fs/kernfs/inode.c:301
1 lock held by blkid/26182:
 #0:  (&ei->i_mmap_sem){++++}, at: [<0000000045873517>] ext4_filemap_fault+0x7c/0xb0 fs/ext4/inode.c:6196
1 lock held by blkid/26184:
 #0:  (&mm->mmap_sem){++++}, at: [<00000000ba651771>] setup_arg_pages+0x255/0x710 fs/exec.c:734
1 lock held by blkid/26185:
 #0:  (&mm->mmap_sem){++++}, at: [<00000000ba651771>] setup_arg_pages+0x255/0x710 fs/exec.c:734
[23190]     0 23190    18211     8992      26       4        0             0 syz-executor.3
1 lock held by udevd/26186:
 #0:  (kernfs_mutex){+.+.}, at: [<000000005f445f4d>] kernfs_iop_permission+0x4e/0x90 fs/kernfs/inode.c:301
1 lock held by udevd/26188:
 #0:  (kernfs_mutex){+.+.}, at: [<000000005664d0eb>] kernfs_dop_revalidate+0x8d/0x370 fs/kernfs/dir.c:570
1 lock held by udevd/26189:
 #0:  (&sig->cred_guard_mutex){+.+.}, at: [<000000003fb3dd20>] prepare_bprm_creds+0x51/0x110 fs/exec.c:1389

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

NMI backtrace for cpu 0
CPU: 0 PID: 23 Comm: khungtaskd Not tainted 4.14.135+ #26
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xca/0x134 lib/dump_stack.c:53
 nmi_cpu_backtrace.cold+0x47/0x86 lib/nmi_backtrace.c:101
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 26111 Comm: blkid Not tainted 4.14.135+ #26
task: 00000000ca107cfd task.stack: 0000000029bf46fc
RIP: 0010:__lock_acquire+0x5d2/0x4320 kernel/locking/lockdep.c:3448
RSP: 0000:ffff88814fc97330 EFLAGS: 00000002
RAX: 0000000000000001 RBX: 0000000000000002 RCX: 1ffff11034dfb114
RDX: 0000000000000008 RSI: ffff8881a6fd8880 RDI: ffff8881a6fd8000
RBP: ffff88814fc97500 R08: 0000000000000001 R09: 0000000000000002
R10: ffff8881a6fd8880 R11: 0000000000000236 R12: ffff8881a6fd88a2
R13: 0000000000040236 R14: ffff8881a6fd8000 R15: 0000000000000000
FS:  00007fad0042e740(0000) GS:ffff8881dbb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc4fea26000 CR3: 000000016e0a8004 CR4: 00000000001606a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 lock_acquire+0x12b/0x360 kernel/locking/lockdep.c:3991
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:152
 spin_lock include/linux/spinlock.h:317 [inline]
 __list_lru_count_one mm/list_lru.c:167 [inline]
 list_lru_count_one+0x7f/0x1d0 mm/list_lru.c:178
 list_lru_shrink_count include/linux/list_lru.h:118 [inline]
 super_cache_count+0x133/0x2b0 fs/super.c:143
 do_shrink_slab mm/vmscan.c:329 [inline]
 shrink_slab.part.0+0x255/0xae0 mm/vmscan.c:505
 shrink_slab mm/vmscan.c:469 [inline]
 shrink_node+0x895/0xc30 mm/vmscan.c:2671
 shrink_zones mm/vmscan.c:2818 [inline]
 do_try_to_free_pages+0x350/0xd80 mm/vmscan.c:2876
 try_to_free_pages+0x27c/0x710 mm/vmscan.c:3082
 __perform_reclaim mm/page_alloc.c:3602 [inline]
 __alloc_pages_direct_reclaim mm/page_alloc.c:3624 [inline]
 __alloc_pages_slowpath mm/page_alloc.c:4011 [inline]
 __alloc_pages_nodemask+0xaee/0x2370 mm/page_alloc.c:4220
 __alloc_pages include/linux/gfp.h:461 [inline]
 __alloc_pages_node include/linux/gfp.h:474 [inline]
 alloc_pages_node include/linux/gfp.h:488 [inline]
 alloc_zeroed_user_highpage_movable include/linux/highmem.h:184 [inline]
 do_anonymous_page mm/memory.c:3133 [inline]
 handle_pte_fault mm/memory.c:3987 [inline]
 __handle_mm_fault+0x1116/0x2700 mm/memory.c:4113
 handle_mm_fault+0x2f1/0x6da mm/memory.c:4150
 __do_page_fault+0x477/0xbb0 arch/x86/mm/fault.c:1423
 page_fault+0x42/0x50 arch/x86/entry/entry_64.S:1120
RIP: 07ff:0xa6b320
RSP: ff552f10:0000000000a6aeb0 EFLAGS: 00000001
Code: c0 44 8b 4c 24 68 44 8b 5c 24 60 0f 84 e9 03 00 00 4c 89 d6 ba 08 00 00 00 4c 89 f7 44 89 5c 24 60 44 89 4c 24 68 4c 89 54 24 70 <e8> 29 e4 ff ff 4c 8b 54 24 70 85 c0 44 8b 4c 24 68 44 8b 5c 24 

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/08/03 15:24 android-4.14 2ea8815046b7 6affd8e8 .config console log report ci-android-414-kasan-gce-root
* Struck through repros no longer work on HEAD.