syzbot


INFO: task hung in fuse_simple_request (2)

Status: upstream: reported on 2024/06/21 20:45
Reported-by: syzbot+2545044aedc75863185f@syzkaller.appspotmail.com
First crash: 221d, last: 22d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in fuse_simple_request (2) 3 101d 219d 0/3 auto-obsoleted due to no activity on 2025/01/28 01:40
linux-5.15 INFO: task hung in fuse_simple_request 12 460d 558d 0/3 auto-obsoleted due to no activity on 2024/02/03 13:59
upstream INFO: task hung in fuse_simple_request fuse C inconclusive error 273 127d 1507d 0/28 upstream: reported C repro on 2020/12/13 21:13
linux-6.1 INFO: task hung in fuse_simple_request 6 437d 526d 0/3 auto-obsoleted due to no activity on 2024/02/26 14:29
upstream INFO: task can't die in request_wait_answer fuse C error 14 1078d 1588d 0/28 auto-obsoleted due to no activity on 2023/04/16 22:02

Sample crash report:
INFO: task syz.8.1345:11766 blocked for more than 143 seconds.
      Not tainted 6.1.123-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.1345      state:D stack:25032 pid:11766 ppid:7180   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 request_wait_answer fs/fuse/dev.c:407 [inline]
 __fuse_request_send fs/fuse/dev.c:426 [inline]
 fuse_simple_request+0x115a/0x1b40 fs/fuse/dev.c:513
 fuse_flush+0x694/0x950 fs/fuse/file.c:521
 filp_close+0xae/0x150 fs/open.c:1431
 __range_close fs/file.c:696 [inline]
 __close_range+0x597/0x7d0 fs/file.c:746
 __do_sys_close_range fs/open.c:1476 [inline]
 __se_sys_close_range fs/open.c:1473 [inline]
 __x64_sys_close_range+0x76/0x80 fs/open.c:1473
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd85c585d29
RSP: 002b:00007ffce6106678 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007fd85c777ba0 RCX: 00007fd85c585d29
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fd85c777ba0 R08: 00000000000000e0 R09: 00007ffce610696f
R10: 00000000003ffcfc R11: 0000000000000246 R12: 000000000008641c
R13: 00007fd85c776080 R14: 0000000000000032 R15: ffffffffffffffff
 </TASK>
INFO: task syz.0.1365:11870 blocked for more than 144 seconds.
      Not tainted 6.1.123-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1365      state:D stack:25864 pid:11870 ppid:7183   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 request_wait_answer fs/fuse/dev.c:407 [inline]
 __fuse_request_send fs/fuse/dev.c:426 [inline]
 fuse_simple_request+0x115a/0x1b40 fs/fuse/dev.c:513
 fuse_flush+0x694/0x950 fs/fuse/file.c:521
 filp_close+0xae/0x150 fs/open.c:1431
 __range_close fs/file.c:696 [inline]
 __close_range+0x597/0x7d0 fs/file.c:746
 __do_sys_close_range fs/open.c:1476 [inline]
 __se_sys_close_range fs/open.c:1473 [inline]
 __x64_sys_close_range+0x76/0x80 fs/open.c:1473
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f74c5b85d29
RSP: 002b:00007ffd2cd8f568 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007f74c5d77ba0 RCX: 00007f74c5b85d29
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f74c5d77ba0 R08: 00000000000001e8 R09: 00007ffd2cd8f85f
R10: 00000000003ffbf4 R11: 0000000000000246 R12: 0000000000088bda
R13: 00007f74c5d76160 R14: 0000000000000032 R15: ffffffffffffffff
 </TASK>
INFO: task syz.7.1372:11903 blocked for more than 145 seconds.
      Not tainted 6.1.123-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.1372      state:D stack:25032 pid:11903 ppid:7175   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 request_wait_answer fs/fuse/dev.c:407 [inline]
 __fuse_request_send fs/fuse/dev.c:426 [inline]
 fuse_simple_request+0x115a/0x1b40 fs/fuse/dev.c:513
 fuse_flush+0x694/0x950 fs/fuse/file.c:521
 filp_close+0xae/0x150 fs/open.c:1431
 __range_close fs/file.c:696 [inline]
 __close_range+0x597/0x7d0 fs/file.c:746
 __do_sys_close_range fs/open.c:1476 [inline]
 __se_sys_close_range fs/open.c:1473 [inline]
 __x64_sys_close_range+0x76/0x80 fs/open.c:1473
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fed88585d29
RSP: 002b:00007ffeb22cc7b8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007fed88777ba0 RCX: 00007fed88585d29
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fed88777ba0 R08: 00000000000000c0 R09: 00007ffeb22ccaaf
R10: 00000000003ffd1c R11: 0000000000000246 R12: 000000000008810b
R13: 00007fed88776160 R14: 0000000000000032 R15: ffffffffffffffff
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d32b290 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d32ba90 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/27:
 #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8d32b0c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510
2 locks held by getty/4010:
 #0: ffff88814d17c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198
1 lock held by syz.3.1859/14800:
2 locks held by dhcpcd-run-hook/14829:
 #0: ffff8880b8e3a9d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xa8/0x140 kernel/sched/core.c:545
 #1: ffff8880b8e27788 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x419/0x790 kernel/sched/psi.c:999
1 lock held by sed/14830:

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 6.1.123-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1ae/0x3f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf88/0xfd0 kernel/hung_task.c:377
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 14835 Comm: dhcpcd-run-hook Not tainted 6.1.123-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:preempt_count_add+0x68/0x180 kernel/sched/core.c:5710
Code: a3 7e 48 c7 c0 60 61 35 97 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 d9 00 00 00 83 3d e1 d2 d6 15 00 75 11 65 8b 05 c0 e0 a3 7e <0f> b6 c0 3d f5 00 00 00 73 59 65 8b 05 af e0 a3 7e 25 ff ff ff 7f
RSP: 0018:ffffc90004ac71e0 EFLAGS: 00000246
RAX: 0000000080000001 RBX: 0000000000000001 RCX: ffffffff97356103
RDX: dffffc0000000000 RSI: ffffffff8151d055 RDI: 0000000000000001
RBP: 1ffff92000958e5c R08: 0000000000000005 R09: ffffc90004ac73d0
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888026cc8000
R13: ffffffff81785810 R14: dffffc0000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff52335f5e8 CR3: 0000000056a77000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 unwind_next_frame+0xb3/0x2220 arch/x86/kernel/unwind_orc.c:433
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x292/0x510 mm/slub.c:3683
 remove_vma mm/mmap.c:143 [inline]
 exit_mmap+0x4cf/0x980 mm/mmap.c:3260
 __mmput+0x115/0x3c0 kernel/fork.c:1200
 exec_mmap+0x4fa/0x5b0 fs/exec.c:1040
 begin_new_exec+0xaf9/0x1dd0 fs/exec.c:1299
 load_elf_binary+0x955/0x2720 fs/binfmt_elf.c:1002
 search_binary_handler fs/exec.c:1741 [inline]
 exec_binprm fs/exec.c:1782 [inline]
 bprm_execve+0x96a/0x18a0 fs/exec.c:1851
 do_execveat_common+0x580/0x720 fs/exec.c:1956
 do_execve fs/exec.c:2030 [inline]
 __do_sys_execve fs/exec.c:2106 [inline]
 __se_sys_execve fs/exec.c:2101 [inline]
 __x64_sys_execve+0x8e/0xa0 fs/exec.c:2101
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ff5232acef7
Code: Unable to access opcode bytes at 0x7ff5232acecd.
RSP: 002b:00007ffc40e7e268 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 000055e2bdc7d020 RCX: 00007ff5232acef7
RDX: 000055e2bdc7d048 RSI: 000055e2bdc7d020 RDI: 000055e2bdc7d0d0
RBP: 000055e2bdc7d0d0 R08: 000055e2bdc7d0d9 R09: 00007ffc40e81e35
R10: 0000000000000008 R11: 0000000000000246 R12: 000055e2bdc7d048
R13: 00007ff52345a904 R14: 000055e2bdc7d048 R15: 0000000000000000
 </TASK>

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/06 16:14 linux-6.1.y 7dc732d24ff7 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in fuse_simple_request
2024/12/16 19:00 linux-6.1.y 52f863f820fd eec85da6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in fuse_simple_request
2024/11/30 23:14 linux-6.1.y e4d90d63d385 68914665 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in fuse_simple_request
2024/11/20 02:02 linux-6.1.y b67dc5c9ade9 7d02db5a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in fuse_simple_request
2024/09/27 22:43 linux-6.1.y e526b12bf916 440b26ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in fuse_simple_request
2024/06/21 20:44 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in fuse_simple_request
* Struck through repros no longer work on HEAD.