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INFO: task hung in htable_put (2)

Status: auto-closed as invalid on 2021/07/01 18:58
Reported-by: syzbot+ba08d638509978ed3bfa@syzkaller.appspotmail.com
First crash: 1852d, last: 1852d
▶ ▼ Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.6 INFO: task hung in htable_put 1 3 247d 283d 0/2 auto-obsoleted due to no activity on 2025/11/01 23:35
upstream INFO: task hung in htable_put 1 C done done 29 2231d 2285d 15/29 fixed on 2020/11/16 12:12
linux-4.19 INFO: task hung in htable_put 1 C done 8 2226d 2272d 1/1 fixed on 2020/03/24 16:08
upstream INFO: task hung in htable_put (2) kernel 1 54 430d 490d 0/29 auto-obsoleted due to no activity on 2025/04/03 01:38
linux-6.6 INFO: task hung in htable_put (2) 1 1 18d 18d 0/2 upstream: reported on 2026/03/11 02:51

Sample crash report:
Bluetooth: hci4: command 0x0406 tx timeout
Bluetooth: hci1: command 0x0406 tx timeout
Bluetooth: hci5: command 0x0406 tx timeout
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
INFO: task syz-executor.5:12138 blocked for more than 140 seconds.
      Not tainted 4.19.177-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D28152 12138   8161 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_timeout+0x92d/0xfe0 kernel/time/timer.c:1794
 do_wait_for_common kernel/sched/completion.c:83 [inline]
 __wait_for_common kernel/sched/completion.c:104 [inline]
 wait_for_common+0x29c/0x470 kernel/sched/completion.c:115
 __flush_work+0x4bb/0x8b0 kernel/workqueue.c:2925
 __cancel_work_timer+0x412/0x590 kernel/workqueue.c:3012
 htable_destroy net/netfilter/xt_hashlimit.c:414 [inline]
 htable_put+0x115/0x1c0 net/netfilter/xt_hashlimit.c:443
 cleanup_match net/ipv4/netfilter/ip_tables.c:463 [inline]
 cleanup_entry+0x12d/0x300 net/ipv4/netfilter/ip_tables.c:648
 do_replace net/ipv4/netfilter/ip_tables.c:1151 [inline]
 do_ipt_set_ctl+0x343/0x420 net/ipv4/netfilter/ip_tables.c:1675
 nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
 nf_setsockopt+0x6f/0xc0 net/netfilter/nf_sockopt.c:115
 ip_setsockopt net/ipv4/ip_sockglue.c:1258 [inline]
 ip_setsockopt+0xd8/0xf0 net/ipv4/ip_sockglue.c:1238
 udp_setsockopt+0x5d/0xa0 net/ipv4/udp.c:2553
 ipv6_setsockopt+0x13f/0x160 net/ipv6/ipv6_sockglue.c:935
 tcp_setsockopt+0x86/0xd0 net/ipv4/tcp.c:3097
 __sys_setsockopt+0x14d/0x240 net/socket.c:1901
 __do_sys_setsockopt net/socket.c:1912 [inline]
 __se_sys_setsockopt net/socket.c:1909 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:1909
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x465ef9
Code: Bad RIP value.
RSP: 002b:00007fa63da2b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 0000000000465ef9
RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00000000004bfa34 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000020000d80 R11: 0000000000000246 R12: 000000000056c008
R13: 00007ffd26456fef R14: 00007fa63da2b300 R15: 0000000000022000

Showing all locks held in the system:
2 locks held by kworker/1:1/25:
1 lock held by khungtaskd/1566:
 #0: 00000000d05cf2c0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440
1 lock held by in:imklog/7817:
 #0: 00000000192b237f (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
1 lock held by syz-executor.5/12138:
 #0: 00000000ccbfe76b (hashlimit_mutex){+.+.}, at: htable_put+0x1a/0x1c0 net/netfilter/xt_hashlimit.c:440

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

NMI backtrace for cpu 0
CPU: 0 PID: 1566 Comm: khungtaskd Not tainted 4.19.177-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x991/0xe60 kernel/hung_task.c:287
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 12133 Comm: syz-executor.2 Not tainted 4.19.177-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:reacquire_held_locks+0x9/0x430 kernel/locking/lockdep.c:3550
Code: 00 e9 26 ea ff ff 4c 8d bc 24 d8 00 00 00 4c 89 ff e8 7b 51 ff ff e9 c7 f0 ff ff 66 0f 1f 44 00 00 48 63 c2 39 d6 48 8d 04 80 <48> 8d 84 c7 88 08 00 00 0f 86 89 02 00 00 83 ee 01 41 57 29 d6 41
RSP: 0018:ffff88804dcbf750 EFLAGS: 00000046
RAX: 000000000000000a RBX: ffffffff8d23b760 RCX: 1ffff110085cbd96
RDX: 0000000000000002 RSI: 0000000000000002 RDI: ffff888042e5e400
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff11009b97eee
R13: b1cf671bc3d80e9f R14: ffff888042e5e400 R15: 0000000000000002
FS:  00007f7a16bf4700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3162a000 CR3: 00000000a9229000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __lock_release kernel/locking/lockdep.c:3706 [inline]
 lock_release+0x379/0x8b0 kernel/locking/lockdep.c:3926
 __raw_spin_unlock include/linux/spinlock_api_smp.h:150 [inline]
 _raw_spin_unlock+0x17/0x40 kernel/locking/spinlock.c:176
 mddev_put drivers/md/md.c:540 [inline]
 md_open+0x20b/0x2a0 drivers/md/md.c:7460
 __blkdev_get+0x372/0x1480 fs/block_dev.c:1494
 blkdev_get+0xb0/0x940 fs/block_dev.c:1627
 blkdev_open+0x202/0x290 fs/block_dev.c:1788
 do_dentry_open+0x4aa/0x1160 fs/open.c:796
 do_last fs/namei.c:3421 [inline]
 path_openat+0x793/0x2df0 fs/namei.c:3537
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x465ef9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7a16bf4188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465ef9
RDX: 0000000000000000 RSI: 00000000200001c0 RDI: ffffffffffffff9c
RBP: 00000000004bfa34 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffdd264b69f R14: 00007f7a16bf4300 R15: 0000000000022000

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/03/03 18:57 linux-4.19.y 2d19be4653f5 06ed56cd .config console log report info ci2-linux-4-19 INFO: task hung in htable_put
* Struck through repros no longer work on HEAD.