syzbot


WARNING in lookup_slow (3)

Status: upstream: reported C repro on 2024/03/30 12:27
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+9642e0afe11301360196@syzkaller.appspotmail.com
First crash: 236d, last: 38d
Bug presence (2)
Date Name Commit Repro Result
2024/06/06 linux-5.15.y (ToT) c61bd26ae81a C [report] WARNING in lookup_slow
2024/06/06 upstream (ToT) 2df0193e62cf C Didn't crash
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 WARNING in lookup_slow (2) 1 386d 386d 0/3 auto-obsoleted due to no activity on 2024/02/09 08:58
upstream WARNING in lookup_slow (2) fs 8 160d 192d 0/28 auto-obsoleted due to no activity on 2024/09/12 01:16
linux-6.1 WARNING in lookup_slow origin:upstream missing-backport C inconclusive 7 91d 354d 0/3 upstream: reported C repro on 2023/12/02 22:03
upstream WARNING in lookup_slow ntfs3 C error inconclusive 34 302d 703d 0/28 auto-obsoleted due to no activity on 2024/05/02 19:30
linux-5.15 WARNING in lookup_slow 1 545d 545d 0/3 auto-obsoleted due to no activity on 2023/09/02 18:27
Last patch testing requests (1)
Created Duration User Patch Repo Result
2024/10/14 14:53 22m retest repro linux-5.15.y report log
Fix bisection attempts (2)
Created Duration User Patch Repo Result
2024/11/09 02:25 11m fix candidate upstream error job log
2024/06/07 04:55 20m fix candidate upstream error job log

Sample crash report:
------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON(!is_rwsem_reader_owned(sem)): count = 0x0, magic = 0xffff0000dc13a810, owner = 0x0, curr 0xffff0000cc66d1c0, list empty
WARNING: CPU: 1 PID: 6800 at kernel/locking/rwsem.c:1323 __up_read+0x568/0x60c kernel/locking/rwsem.c:1323
Modules linked in:
CPU: 1 PID: 6800 Comm: syz-executor763 Not tainted 5.15.160-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __up_read+0x568/0x60c kernel/locking/rwsem.c:1323
lr : __up_read+0x568/0x60c kernel/locking/rwsem.c:1323
sp : ffff8000213e77a0
x29: ffff8000213e7820 x28: 1ffff0000292a06a x27: ffff800014950000
x26: dfff800000000000 x25: 0000000000000000 x24: ffff0000dc13a868
x23: ffff0000cc66d1c0 x22: ffff8000213e77c0 x21: 0000000000000000
x20: ffff0000dc13a810 x19: ffff0000dc13a810 x18: 0000000000000001
x17: 0000000000000000 x16: ffff80001199c494 x15: 00000000ffffffff
x14: ffff0000cc66d1c0 x13: 0000000000000001 x12: 0000000000000001
x11: 0000000000000000 x10: 0000000000000000 x9 : 754b04e49f92a400
x8 : 754b04e49f92a400 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000213e6f18 x4 : ffff800014a2f7a0 x3 : ffff8000085501f8
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 000000000000008c
Call trace:
 __up_read+0x568/0x60c kernel/locking/rwsem.c:1323
 up_read+0x94/0xe8 kernel/locking/rwsem.c:1594
 inode_unlock_shared include/linux/fs.h:804 [inline]
 lookup_slow+0x6c/0x84 fs/namei.c:1681
 walk_component+0x394/0x4cc fs/namei.c:1976
 lookup_last fs/namei.c:2431 [inline]
 path_lookupat+0x13c/0x3d0 fs/namei.c:2455
 filename_lookup+0x1c4/0x4c8 fs/namei.c:2484
 user_path_at_empty+0x5c/0x1a4 fs/namei.c:2883
 user_path_at include/linux/namei.h:57 [inline]
 do_mount fs/namespace.c:3345 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount fs/namespace.c:3533 [inline]
 __arm64_sys_mount+0x4dc/0x5e0 fs/namespace.c:3533
 __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
irq event stamp: 98
hardirqs last  enabled at (97): [<ffff80000832b458>] __up_console_sem+0xb4/0x100 kernel/printk/printk.c:257
hardirqs last disabled at (98): [<ffff800011997b20>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:396
softirqs last  enabled at (8): [<ffff8000080310b0>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:31
softirqs last disabled at (6): [<ffff80000803107c>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:18
---[ end trace 1edc1a2e1c82ea4d ]---
------------[ cut here ]------------
DEBUG_RWSEMS_WARN_ON(tmp < 0): count = 0xffffffffffffff00, magic = 0xffff0000dc13a810, owner = 0x0, curr 0xffff0000cc66d1c0, list empty
WARNING: CPU: 1 PID: 6800 at kernel/locking/rwsem.c:1328 __up_read+0x3d0/0x60c kernel/locking/rwsem.c:1328
Modules linked in:
CPU: 1 PID: 6800 Comm: syz-executor763 Tainted: G        W         5.15.160-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : __up_read+0x3d0/0x60c kernel/locking/rwsem.c:1328
lr : __up_read+0x3d0/0x60c kernel/locking/rwsem.c:1328
sp : ffff8000213e77a0
x29: ffff8000213e7820 x28: 1ffff0000292a06a x27: ffff800014950000
x26: dfff800000000000 x25: ffffffffffffff00 x24: ffff0000dc13a868
x23: ffff0000dc13a810 x22: ffffffffffffff00 x21: 0000000000000000
x20: ffff0000cc66d1c0 x19: ffff0000dc13a810 x18: 0000000000000002
x17: 0000000000000000 x16: ffff80001199c494 x15: 00000000ffffffff
x14: ffff0000cc66d1c0 x13: 0000000000000001 x12: 0000000000000001
x11: 0000000000000001 x10: 0000000000000000 x9 : 754b04e49f92a400
x8 : 754b04e49f92a400 x7 : 0000000000000001 x6 : 0000000000000001
x5 : ffff8000213e6f18 x4 : ffff800014a2f7a0 x3 : ffff80000a9795c0
x2 : ffff0001b480ad10 x1 : 0000000000000001 x0 : 0000000000000087
Call trace:
 __up_read+0x3d0/0x60c kernel/locking/rwsem.c:1328
 up_read+0x94/0xe8 kernel/locking/rwsem.c:1594
 inode_unlock_shared include/linux/fs.h:804 [inline]
 lookup_slow+0x6c/0x84 fs/namei.c:1681
 walk_component+0x394/0x4cc fs/namei.c:1976
 lookup_last fs/namei.c:2431 [inline]
 path_lookupat+0x13c/0x3d0 fs/namei.c:2455
 filename_lookup+0x1c4/0x4c8 fs/namei.c:2484
 user_path_at_empty+0x5c/0x1a4 fs/namei.c:2883
 user_path_at include/linux/namei.h:57 [inline]
 do_mount fs/namespace.c:3345 [inline]
 __do_sys_mount fs/namespace.c:3556 [inline]
 __se_sys_mount fs/namespace.c:3533 [inline]
 __arm64_sys_mount+0x4dc/0x5e0 fs/namespace.c:3533
 __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
irq event stamp: 143
hardirqs last  enabled at (143): [<ffff80001199a928>] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:81 [inline]
hardirqs last  enabled at (143): [<ffff80001199a928>] exit_to_kernel_mode+0x100/0x178 arch/arm64/kernel/entry-common.c:91
hardirqs last disabled at (142): [<ffff800011a5f488>] preempt_schedule_irq+0xac/0x274 kernel/sched/core.c:6781
softirqs last  enabled at (138): [<ffff800008021c64>] softirq_handle_end kernel/softirq.c:401 [inline]
softirqs last  enabled at (138): [<ffff800008021c64>] __do_softirq+0xb5c/0xdb0 kernel/softirq.c:587
softirqs last disabled at (101): [<ffff8000081b6568>] do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline]
softirqs last disabled at (101): [<ffff8000081b6568>] invoke_softirq kernel/softirq.c:439 [inline]
softirqs last disabled at (101): [<ffff8000081b6568>] __irq_exit_rcu+0x264/0x4d4 kernel/softirq.c:637
---[ end trace 1edc1a2e1c82ea4e ]---

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/06/06 01:23 linux-5.15.y c61bd26ae81a 5aa1a7c9 .config console log report syz / log C [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-5-15-kasan-arm64 WARNING in lookup_slow
2024/09/27 18:57 linux-5.15.y 3a5928702e71 440b26ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in lookup_slow
2024/04/11 23:21 linux-5.15.y cdfd0a7f0139 95ed9ece .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in lookup_slow
2024/05/20 01:22 linux-5.15.y 83655231580b c0f1611a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in lookup_slow
2024/03/30 12:26 linux-5.15.y 9465fef4ae35 6baf5069 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING in lookup_slow
* Struck through repros no longer work on HEAD.