syzbot


INFO: task hung in fuse_lookup (4)

Status: upstream: reported C repro on 2022/12/13 09:09
Subsystems: reiserfs
[Documentation on labels]
Reported-by: syzbot+5ff67b1ca8d080c6eab0@syzkaller.appspotmail.com
First crash: 489d, last: 434d
Similar bugs (10)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.14 INFO: task hung in fuse_lookup 4 1658d 1811d 0/1 auto-closed as invalid on 2020/01/29 21:30
linux-4.19 INFO: task hung in fuse_lookup reiserfs C error 12 429d 1707d 0/1 upstream: reported C repro on 2019/08/14 05:24
linux-4.14 INFO: task hung in fuse_lookup (3) 1 822d 822d 0/1 auto-closed as invalid on 2022/05/15 00:47
linux-6.1 INFO: task hung in fuse_lookup origin:upstream syz 3 14d 314d 0/3 upstream: reported syz repro on 2023/06/07 05:32
upstream INFO: task hung in fuse_lookup (3) fuse C done error 45 1d22h 1706d 0/26 upstream: reported C repro on 2019/08/14 09:48
linux-5.15 INFO: task hung in fuse_lookup origin:upstream syz error 2 293d 314d 0/3 upstream: reported syz repro on 2023/06/07 02:49
linux-4.14 INFO: task hung in fuse_lookup (2) 1 1492d 1492d 0/1 auto-closed as invalid on 2020/07/13 23:30
upstream INFO: task hung in fuse_lookup fuse 16 2051d 2102d 0/26 closed as invalid on 2018/09/05 12:51
android-49 INFO: task hung in fuse_lookup C 112 1620d 1831d 0/3 public: reported C repro on 2019/04/11 08:44
upstream INFO: task hung in fuse_lookup (2) fuse C 13 1885d 2044d 0/26 closed as dup on 2018/09/10 08:43
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2023/02/06 13:51 28m bisect fix linux-4.14.y job log (0) log

Sample crash report:
IPVS: ftp: loaded support on port[0] = 21
INFO: task syz-executor135:7959 blocked for more than 140 seconds.
      Not tainted 4.14.301-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor135 D28368  7959   7958 0x00000000
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 fuse_lock_inode+0xb0/0xe0 fs/fuse/inode.c:371
 fuse_lookup+0xa0/0x3e0 fs/fuse/dir.c:370
 lookup_slow+0x20a/0x400 fs/namei.c:1696
 walk_component+0x6a1/0xbc0 fs/namei.c:1825
 link_path_walk+0x823/0x10a0 fs/namei.c:2154
 path_openat+0x15e/0x2970 fs/namei.c:3570
 do_filp_open+0x179/0x3c0 fs/namei.c:3605
 do_sys_open+0x296/0x410 fs/open.c:1081
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3
RIP: 0033:0x7ff446989e58
RSP: 002b:00007ffc9feb3410 EFLAGS: 00000287 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ffc9feb3480 RCX: 00007ff446989e58
RDX: 0000000000090800 RSI: 00007ff4469e0004 RDI: 00000000ffffff9c
RBP: 0000000000000002 R08: 0000000000090800 R09: 00007ff4469e0004
R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffc9feb360c
R13: 0000000000000002 R14: 00007ffc9feb3660 R15: 00007ffc9feb3650
INFO: task syz-executor135:7986 blocked for more than 140 seconds.
      Not tainted 4.14.301-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor135 D27488  7986   7959 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 request_wait_answer+0x30d/0x620 fs/fuse/dev.c:478
 __fuse_request_send+0x108/0x1a0 fs/fuse/dev.c:498
 fuse_request_send fs/fuse/dev.c:511 [inline]
 fuse_simple_request+0x2fa/0x790 fs/fuse/dev.c:569
 fuse_lookup_name+0x228/0x550 fs/fuse/dir.c:330
 fuse_lookup+0x102/0x3e0 fs/fuse/dir.c:371
 lookup_slow+0x20a/0x400 fs/namei.c:1696
 walk_component+0x6a1/0xbc0 fs/namei.c:1825
 link_path_walk+0x823/0x10a0 fs/namei.c:2154
 path_lookupat+0xcb/0x780 fs/namei.c:2342
 do_o_path fs/namei.c:3530 [inline]
 path_openat+0x18eb/0x2970 fs/namei.c:3559
 do_filp_open+0x179/0x3c0 fs/namei.c:3605
 do_sys_open+0x296/0x410 fs/open.c:1081
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3
RIP: 0033:0x7ff44698a1c9
RSP: 002b:00007ff44691a2f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ff446a134d0 RCX: 00007ff44698a1c9
RDX: 0000000000200000 RSI: 0000000020000340 RDI: ffffffffffffff9c
RBP: 00007ff4469e01bc R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0030656c69662f2e
R13: 65646f6d746f6f72 R14: 6873612f7665642f R15: 00007ff446a134d8

Showing all locks held in the system:
1 lock held by khungtaskd/1533:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff8702b144>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
2 locks held by syz-executor135/7959:
 #0:  (&type->i_mutex_dir_key#7){++++}, at: [<ffffffff81893089>] inode_lock_shared include/linux/fs.h:729 [inline]
 #0:  (&type->i_mutex_dir_key#7){++++}, at: [<ffffffff81893089>] lookup_slow+0x129/0x400 fs/namei.c:1674
 #1:  (&fi->mutex){+.+.}, at: [<ffffffff82309580>] fuse_lock_inode+0xb0/0xe0 fs/fuse/inode.c:371
2 locks held by syz-executor135/7986:
 #0:  (&type->i_mutex_dir_key#7){++++}, at: [<ffffffff81893089>] inode_lock_shared include/linux/fs.h:729 [inline]
 #0:  (&type->i_mutex_dir_key#7){++++}, at: [<ffffffff81893089>] lookup_slow+0x129/0x400 fs/namei.c:1674
 #1:  (&fi->mutex){+.+.}, at: [<ffffffff82309580>] fuse_lock_inode+0xb0/0xe0 fs/fuse/inode.c:371

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

NMI backtrace for cpu 1
CPU: 1 PID: 1533 Comm: khungtaskd Not tainted 4.14.301-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4627 Comm: systemd-journal Not tainted 4.14.301-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
task: ffff8880a11fa200 task.stack: ffff8880a1200000
RIP: 0010:page_expected_state mm/page_alloc.c:918 [inline]
RIP: 0010:check_new_page mm/page_alloc.c:1718 [inline]
RIP: 0010:check_new_pages mm/page_alloc.c:1759 [inline]
RIP: 0010:rmqueue mm/page_alloc.c:2845 [inline]
RIP: 0010:get_page_from_freelist+0x1016/0x25a0 mm/page_alloc.c:3173
RSP: 0018:ffff8880a12079f8 EFLAGS: 00000046
RAX: 00000000ffffffff RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea000255dc58
RBP: ffffea000255dc40 R08: ffffffff8b9c10e0 R09: 00000000000c001e
R10: dffffc0000000000 R11: 0000000000000100 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff88813fffb6c0
FS:  00007fa57eca68c0(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa57c07b000 CR3: 00000000a18f1000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __alloc_pages_nodemask+0x352/0x2900 mm/page_alloc.c:4219
 __alloc_pages include/linux/gfp.h:484 [inline]
 __alloc_pages_node include/linux/gfp.h:497 [inline]
 kmem_getpages mm/slab.c:1419 [inline]
 cache_grow_begin+0x91/0x700 mm/slab.c:2676
 cache_alloc_refill+0x273/0x350 mm/slab.c:3043
 ____cache_alloc mm/slab.c:3125 [inline]
 __do_cache_alloc mm/slab.c:3347 [inline]
 slab_alloc mm/slab.c:3382 [inline]
 kmem_cache_alloc+0x333/0x3c0 mm/slab.c:3550
 getname_flags+0xc8/0x550 fs/namei.c:138
 user_path_at_empty+0x2a/0x50 fs/namei.c:2631
 user_path_at include/linux/namei.h:57 [inline]
 SYSC_faccessat fs/open.c:403 [inline]
 SyS_faccessat+0x21b/0x680 fs/open.c:353
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3
RIP: 0033:0x7fa57df619c7
RSP: 002b:00007ffff6ba6808 EFLAGS: 00000246 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 00007ffff6ba9830 RCX: 00007fa57df619c7
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000055d53361c9a3
RBP: 00007ffff6ba6950 R08: 000055d5336123e5 R09: 0000000000000018
R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 000055d534b3a8a0 R15: 00007ffff6ba6e40
Code: 04 00 00 48 8d 7d 18 48 89 f8 48 c1 e8 03 42 0f b6 14 28 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 18 14 00 00 8b 45 18 <83> f8 ff 0f 84 3c ff ff ff 48 89 ef e8 39 40 ff ff 8b 4c 24 18 

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/12/13 09:09 linux-4.14.y 65afe34ac33d 67be1ae7 .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-4-14 INFO: task hung in fuse_lookup
2023/01/07 12:34 linux-4.14.y c4215ee4771b 1dac8c7a .config console log report syz [disk image] [vmlinux] [kernel image] [mounted in repro] ci2-linux-4-14 INFO: task hung in fuse_lookup
* Struck through repros no longer work on HEAD.