syzbot


INFO: task hung in fuse_simple_request

Status: auto-obsoleted due to no activity on 2024/02/26 14:29
Reported-by: syzbot+bb2fc284294101ec8e93@syzkaller.appspotmail.com
First crash: 272d, last: 183d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in fuse_simple_request 12 206d 305d 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 254 13d 1253d 0/26 upstream: reported C repro on 2020/12/13 21:13
upstream INFO: task can't die in request_wait_answer fuse C error 14 824d 1335d 0/26 auto-obsoleted due to no activity on 2023/04/16 22:02

Sample crash report:
INFO: task syz-executor.2:16889 blocked for more than 145 seconds.
      Not tainted 6.1.57-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:23576 pid:16889 ppid:3588   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6554
 schedule+0xbf/0x180 kernel/sched/core.c:6630
 request_wait_answer fs/fuse/dev.c:407 [inline]
 __fuse_request_send fs/fuse/dev.c:426 [inline]
 fuse_simple_request+0x106e/0x18d0 fs/fuse/dev.c:511
 fuse_readlink_page fs/fuse/dir.c:1404 [inline]
 fuse_symlink_read_folio+0x2e1/0x660 fs/fuse/dir.c:1994
 filemap_read_folio+0x199/0x780 mm/filemap.c:2407
 do_read_cache_folio+0x2ee/0x810 mm/filemap.c:3535
 do_read_cache_page+0x32/0x220 mm/filemap.c:3577
 read_mapping_page include/linux/pagemap.h:756 [inline]
 page_get_link+0x53/0x4a0 fs/namei.c:5083
 fuse_get_link+0x44e/0x6d0 fs/fuse/dir.c:1432
 pick_link+0x6e9/0xe20
 step_into+0xc9b/0x1070 fs/namei.c:1863
 walk_component fs/namei.c:1999 [inline]
 link_path_walk+0x72c/0xee0 fs/namei.c:2320
 path_lookupat+0xa9/0x450 fs/namei.c:2473
 filename_lookup+0x251/0x600 fs/namei.c:2503
 user_path_at_empty+0x40/0x180 fs/namei.c:2876
 user_path_at include/linux/namei.h:57 [inline]
 ksys_umount fs/namespace.c:1822 [inline]
 __do_sys_umount fs/namespace.c:1830 [inline]
 __se_sys_umount fs/namespace.c:1828 [inline]
 __x64_sys_umount+0xf0/0x170 fs/namespace.c:1828
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3b9987cae9
RSP: 002b:00007f3b9a5780c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007f3b9999bf80 RCX: 00007f3b9987cae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000180
RBP: 00007f3b998c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f3b9999bf80 R15: 00007fff8fee2348
 </TASK>
INFO: task syz-executor.2:16893 blocked for more than 147 seconds.
      Not tainted 6.1.57-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:25656 pid:16893 ppid:3588   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6554
 schedule+0xbf/0x180 kernel/sched/core.c:6630
 request_wait_answer fs/fuse/dev.c:407 [inline]
 __fuse_request_send fs/fuse/dev.c:426 [inline]
 fuse_simple_request+0x106e/0x18d0 fs/fuse/dev.c:511
 fuse_dentry_revalidate+0x50f/0xb20 fs/fuse/dir.c:243
 d_revalidate fs/namei.c:856 [inline]
 __lookup_slow+0x1b3/0x3d0 fs/namei.c:1674
 lookup_slow+0x53/0x70 fs/namei.c:1702
 walk_component fs/namei.c:1993 [inline]
 link_path_walk+0x9d6/0xee0 fs/namei.c:2320
 path_lookupat+0xa9/0x450 fs/namei.c:2473
 filename_lookup+0x251/0x600 fs/namei.c:2503
 user_path_at_empty+0x40/0x180 fs/namei.c:2876
 user_path_at include/linux/namei.h:57 [inline]
 __do_sys_pivot_root fs/namespace.c:3879 [inline]
 __se_sys_pivot_root+0x17e/0x1640 fs/namespace.c:3868
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3b9987cae9
RSP: 002b:00007f3b9a5570c8 EFLAGS: 00000246 ORIG_RAX: 000000000000009b
RAX: ffffffffffffffda RBX: 00007f3b9999c050 RCX: 00007f3b9987cae9
RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000020000080
RBP: 00007f3b998c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f3b9999c050 R15: 00007fff8fee2348
 </TASK>
INFO: task syz-executor.2:16895 blocked for more than 149 seconds.
      Not tainted 6.1.57-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:26456 pid:16895 ppid:3588   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6554
 schedule+0xbf/0x180 kernel/sched/core.c:6630
 io_schedule+0x88/0x100 kernel/sched/core.c:8782
 folio_wait_bit_common+0x878/0x1290 mm/filemap.c:1296
 folio_put_wait_locked mm/filemap.c:1465 [inline]
 do_read_cache_folio+0xb9/0x810 mm/filemap.c:3517
 do_read_cache_page+0x32/0x220 mm/filemap.c:3577
 read_mapping_page include/linux/pagemap.h:756 [inline]
 page_get_link+0x53/0x4a0 fs/namei.c:5083
 fuse_get_link+0x44e/0x6d0 fs/fuse/dir.c:1432
 pick_link+0x6e9/0xe20
 step_into+0xc9b/0x1070 fs/namei.c:1863
 walk_component fs/namei.c:1999 [inline]
 link_path_walk+0x72c/0xee0 fs/namei.c:2320
 path_lookupat+0xa9/0x450 fs/namei.c:2473
 filename_lookup+0x251/0x600 fs/namei.c:2503
 user_path_at_empty+0x40/0x180 fs/namei.c:2876
 user_path_at include/linux/namei.h:57 [inline]
 __do_sys_chroot fs/open.c:562 [inline]
 __se_sys_chroot+0xbb/0x2b0 fs/open.c:556
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3b9987cae9
RSP: 002b:00007f3b9a5360c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a1
RAX: ffffffffffffffda RBX: 00007f3b9999c120 RCX: 00007f3b9987cae9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040
RBP: 00007f3b998c847a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f3b9999c120 R15: 00007fff8fee2348
 </TASK>
INFO: task syz-executor.2:16901 blocked for more than 149 seconds.
      Not tainted 6.1.57-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:24600 pid:16901 ppid:3588   flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6554
 schedule+0xbf/0x180 kernel/sched/core.c:6630
 io_schedule+0x88/0x100 kernel/sched/core.c:8782
 folio_wait_bit_common+0x878/0x1290 mm/filemap.c:1296
 folio_put_wait_locked mm/filemap.c:1465 [inline]
 do_read_cache_folio+0xb9/0x810 mm/filemap.c:3517
 do_read_cache_page+0x32/0x220 mm/filemap.c:3577
 read_mapping_page include/linux/pagemap.h:756 [inline]
 page_get_link+0x53/0x4a0 fs/namei.c:5083
 fuse_get_link+0x44e/0x6d0 fs/fuse/dir.c:1432
 pick_link+0x6e9/0xe20
 step_into+0xc9b/0x1070 fs/namei.c:1863
 walk_component fs/namei.c:1999 [inline]
 link_path_walk+0x72c/0xee0 fs/namei.c:2320
 path_lookupat+0xa9/0x450 fs/namei.c:2473
 filename_lookup+0x251/0x600 fs/namei.c:2503
 kern_path+0x37/0x180 fs/namei.c:2593
 tomoyo_mount_acl security/tomoyo/mount.c:136 [inline]
 tomoyo_mount_permission+0x8df/0xb60 security/tomoyo/mount.c:237
 security_sb_mount+0x88/0xc0 security/security.c:993
 path_mount+0xbd/0x1090 fs/namespace.c:3312
 do_mount fs/namespace.c:3383 [inline]
 __do_sys_mount fs/namespace.c:3591 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3568
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3b9987cae9
RSP: 002b:00007f3b9a5150c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f3b9999c1f0 RCX: 00007f3b9987cae9
RDX: 0000000020000880 RSI: 0000000020001a80 RDI: 0000000020001ac0
RBP: 00007f3b998c847a R08: 0000000020001b00 R09: 0000000000000000
R10: 00000000000d1803 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f3b9999c1f0 R15: 00007fff8fee2348
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u4:0/9:
 #0: ffff88801260e938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc900000e7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #2: ffffffff8e28f750 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:563
 #3: ffffffff8e29ba68 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xd7/0x630 net/core/dev.c:11326
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d12a1b0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d12a9b0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
2 locks held by kworker/0:1/14:
 #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
 #1: ffffc90000137d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
1 lock held by khungtaskd/28:
 #0: ffffffff8d129fe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline]
 #0: ffffffff8d129fe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline]
 #0: ffffffff8d129fe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6493
2 locks held by getty/3304:
 #0: ffff888013e7f098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188
2 locks held by kworker/u4:23/4654:
1 lock held by syz-executor.2/16893:
 #0: ffff88803b6e0810 (&type->i_mutex_dir_key#20){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:766 [inline]
 #0: ffff88803b6e0810 (&type->i_mutex_dir_key#20){++++}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1701
1 lock held by syz-executor.2/16901:
 #0: ffffffff8d712fc8 (tomoyo_ss){....}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:306 [inline]
 #0: ffffffff8d712fc8 (tomoyo_ss){....}-{0:0}, at: srcu_read_lock include/linux/srcu.h:165 [inline]
 #0: ffffffff8d712fc8 (tomoyo_ss){....}-{0:0}, at: tomoyo_read_lock security/tomoyo/common.h:1110 [inline]
 #0: ffffffff8d712fc8 (tomoyo_ss){....}-{0:0}, at: tomoyo_mount_permission+0x283/0xb60 security/tomoyo/mount.c:236
1 lock held by syz-executor.1/18566:
 #0: ffffffff8e29ba68 (rtnl_mutex){+.+.}-{3:3}, at: do_ip_setsockopt+0x51d/0x3bb0 net/ipv4/ip_sockglue.c:954
1 lock held by syz-executor.1/18568:
 #0: ffffffff8e29ba68 (rtnl_mutex){+.+.}-{3:3}, at: do_ip_setsockopt+0x51d/0x3bb0 net/ipv4/ip_sockglue.c:954
2 locks held by syz-executor.2/18595:

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.57-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
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+0x1b0/0x3f0 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:306
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4192 Comm: kworker/u4:20 Not tainted 6.1.57-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Workqueue: phy16 ieee80211_iface_work
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x68/0x290 mm/kasan/generic.c:189
Code: fc ff df 4e 8d 0c 03 4c 8d 54 37 ff 49 c1 ea 03 49 bb 01 00 00 00 00 fc ff df 4f 8d 34 1a 4c 89 f5 4c 29 cd 48 83 fd 10 7f 26 <48> 85 ed 0f 84 3a 01 00 00 49 f7 d2 49 01 da 41 80 39 00 0f 85 c4
RSP: 0018:ffffc9000c11f6f8 EFLAGS: 00000083
RAX: 0000000000000001 RBX: 1ffffffff209307a RCX: ffffffff816a45fc
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff904983d0
RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff209307a
R10: 1ffffffff209307a R11: dffffc0000000001 R12: 0000000000000000
R13: ffff8880324a6440 R14: fffffbfff209307b R15: 1ffff11006494c04
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc745b75198 CR3: 0000000072d4f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 hlock_class kernel/locking/lockdep.c:228 [inline]
 check_wait_context kernel/locking/lockdep.c:4747 [inline]
 __lock_acquire+0x78c/0x1f80 kernel/locking/lockdep.c:4998
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5661
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747
 sdata_lock net/mac80211/ieee80211_i.h:1114 [inline]
 ieee80211_ibss_work+0xa0/0x1480 net/mac80211/ibss.c:1680
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/10/12 11:57 linux-6.1.y 082280fe94a0 1b231e3c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in fuse_simple_request
2023/10/09 20:58 linux-6.1.y ecda77b46871 3c53c7d9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in fuse_simple_request
2023/09/11 19:42 linux-6.1.y 59b13c2b647e 59da8366 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in fuse_simple_request
2023/11/18 14:28 linux-6.1.y fb2635ac69ab cb976f63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: task hung in fuse_simple_request
2023/08/24 00:25 linux-6.1.y 802aacbbffe2 b81ca3f6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in fuse_simple_request
2023/08/22 02:59 linux-6.1.y 6c44e13dc284 6b415825 .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.