syzbot


INFO: task hung in vfs_rename (2)

Status: upstream: reported on 2024/09/22 20:09
Reported-by: syzbot+0686005e7b904c0c6479@syzkaller.appspotmail.com
First crash: 75d, last: 74d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in vfs_rename 1 208d 208d 0/3 auto-obsoleted due to no activity on 2024/08/20 18:33
upstream INFO: task hung in vfs_rename bcachefs f2fs 72 18d 81d 0/28 upstream: reported on 2024/09/16 14:01

Sample crash report:
INFO: task syz.3.177:4904 blocked for more than 143 seconds.
      Not tainted 5.15.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.177       state:D stack:23808 pid: 4904 ppid:  4409 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 rwsem_down_write_slowpath+0xf0c/0x16a0 kernel/locking/rwsem.c:1165
 vfs_rename+0x7e4/0x10f0 fs/namei.c:4803
 do_renameat2+0xe0f/0x1700 fs/namei.c:4985
 __do_sys_rename fs/namei.c:5031 [inline]
 __se_sys_rename fs/namei.c:5029 [inline]
 __x64_sys_rename+0x82/0x90 fs/namei.c:5029
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f542f692ef9
RSP: 002b:00007f542daea038 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007f542f84b058 RCX: 00007f542f692ef9
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 00000000200001c0
RBP: 00007f542f705b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f542f84b058 R15: 00007ffffad98468
 </TASK>
INFO: task syz.3.177:4905 blocked for more than 144 seconds.
      Not tainted 5.15.167-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.177       state:D stack:24384 pid: 4905 ppid:  4409 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
 rwsem_down_read_slowpath+0x605/0xb40 kernel/locking/rwsem.c:1055
 __down_read_common kernel/locking/rwsem.c:1239 [inline]
 __down_read kernel/locking/rwsem.c:1252 [inline]
 down_read+0x9a/0x2e0 kernel/locking/rwsem.c:1500
 inode_lock_shared include/linux/fs.h:799 [inline]
 lookup_slow+0x45/0x70 fs/namei.c:1679
 walk_component+0x48c/0x610 fs/namei.c:1976
 lookup_last fs/namei.c:2431 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2455
 do_o_path+0x91/0x230 fs/namei.c:3713
 path_openat+0x2944/0x2f20 fs/namei.c:3735
 do_filp_open+0x21c/0x460 fs/namei.c:3769
 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1280
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f542f692ef9
RSP: 002b:00007f542dac9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f542f84b130 RCX: 00007f542f692ef9
RDX: 0000000000200000 RSI: 0000000020000180 RDI: ffffffffffffff9c
RBP: 00007f542f705b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f542f84b130 R15: 00007ffffad98468
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c91fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:2/154:
4 locks held by kworker/u4:3/1122:
 #0: ffff888142fc9138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90004fefd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff888057f5a0e0 (&type->s_umount_key#56){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:418
 #3: ffff888020215108 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4d4/0x6a0 fs/f2fs/segment.c:528
2 locks held by getty/3327:
 #0: ffff88814b8c5098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc9000249b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
3 locks held by kworker/1:3/3570:
 #0: ffff888017070938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90002dc7d20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8da31d88 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
3 locks held by kworker/1:10/3835:
 #0: ffff88814b018538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90003b47d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8da31d88 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4113
5 locks held by kworker/u4:8/3893:
 #0: ffff8880171d5938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90002f27d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8da261d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:561
 #3: ffffffff8da31d88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock_unregistering net/core/dev.c:11580 [inline]
 #3: ffffffff8da31d88 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0x1ac/0x3f0 net/core/dev.c:11618
 #4: ffffffff8c924228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #4: ffffffff8c924228 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845
3 locks held by kworker/u4:13/4696:
 #0: ffff888017079138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90003917d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8da31d88 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
6 locks held by syz.3.177/4866:
3 locks held by syz.3.177/4904:
 #0: ffff888057f5a460 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377
 #1: ffff8880692569d0 (&type->i_mutex_dir_key#9/1){+.+.}-{3:3}, at: do_renameat2+0x67e/0x1700 fs/namei.c:4924
 #2: ffff8880692543d0 (&sb->s_type->i_mutex_key#21/4){+.+.}-{3:3}, at: vfs_rename+0x7e4/0x10f0 fs/namei.c:4803
1 lock held by syz.3.177/4905:
 #0: ffff8880692569d0 (&type->i_mutex_dir_key#11){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:799 [inline]
 #0: ffff8880692569d0 (&type->i_mutex_dir_key#11){++++}-{3:3}, at: lookup_slow+0x45/0x70 fs/namei.c:1679
2 locks held by udevd/6061:
3 locks held by kworker/0:14/6274:
 #0: ffff88814b018538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90003907d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffffffff8da31d88 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4113
2 locks held by syz.0.397/6472:

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6085 Comm: syz-executor Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:might_alloc include/linux/sched/mm.h:206 [inline]
RIP: 0010:slab_pre_alloc_hook+0x1b/0xc0 mm/slab.h:492
Code: 4b f2 6a 08 66 2e 0f 1f 84 00 00 00 00 00 90 55 41 57 41 56 41 55 41 54 53 89 cd 49 89 d7 49 89 f6 49 89 fc 23 2d cd 0e 20 0c <89> ef e8 4e 46 f6 ff 89 ef e8 67 47 f6 ff f7 c5 00 04 00 00 74 18
RSP: 0018:ffffc90002ee7af8 EFLAGS: 00000002
RAX: 6f05aff738846500 RBX: 0000000000000001 RCX: 0000000000000a20
RDX: 0000000000000001 RSI: ffffc90002ee7b30 RDI: ffff888017d53140
RBP: 0000000000000a20 R08: ffffffff814fe18d R09: fffffbfff1bd2c16
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888017d53140
R13: dffffc0000000000 R14: ffffc90002ee7b30 R15: 0000000000000001
FS:  0000555576e44500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7a48009d58 CR3: 000000006691f000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 slab_alloc_node mm/slub.c:3134 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0x3f/0x280 mm/slub.c:3233
 __sigqueue_alloc+0x3be/0x4d0 kernel/signal.c:435
 __send_signal+0x21f/0xd40 kernel/signal.c:1116
 do_send_sig_info kernel/signal.c:1294 [inline]
 group_send_sig_info+0x260/0x2d0 kernel/signal.c:1442
 bpf_send_signal_common+0x2d8/0x420 kernel/trace/bpf_trace.c:824
 ____bpf_send_signal kernel/trace/bpf_trace.c:829 [inline]
 bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:827
 bpf_prog_7ba5217f62dcd359+0x38/0x134
 bpf_dispatcher_nop_func include/linux/bpf.h:790 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1880 [inline]
 bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917
 __bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18
 trace_sys_enter include/trace/events/syscalls.h:18 [inline]
 syscall_trace_enter kernel/entry/common.c:77 [inline]
 __syscall_enter_from_user_work kernel/entry/common.c:96 [inline]
 syscall_enter_from_user_mode+0x202/0x240 kernel/entry/common.c:114
 do_syscall_64+0x1e/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8947233879
Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 04 25
RSP: 002b:00007ffea3cecd40 EFLAGS: 00000246 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007f8947f7e620 RCX: 00007f8947233879
RDX: 00007ffea3cecd40 RSI: 00007ffea3cece70 RDI: 0000000000000011
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f8947f7e670 R15: 0000000000000000
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/23 05:05 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in vfs_rename
2024/09/22 20:08 linux-5.15.y 3a5928702e71 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: task hung in vfs_rename
* Struck through repros no longer work on HEAD.