syzbot


INFO: task hung in __netlink_dump_start (2)

Status: auto-closed as invalid on 2022/06/25 14:03
Reported-by: syzbot+6c484922c3dd8ff8032d@syzkaller.appspotmail.com
First crash: 871d, last: 871d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in __netlink_dump_start (2) net 5 919d 1001d 0/27 closed as invalid on 2022/02/07 19:19
linux-4.19 INFO: task hung in __netlink_dump_start 1 1501d 1501d 0/1 auto-closed as invalid on 2020/10/04 12:25
upstream INFO: task hung in __netlink_dump_start net 2 1369d 1383d 0/27 auto-closed as invalid on 2021/01/13 23:36
linux-5.15 INFO: task hung in __netlink_dump_start 14 20d 149d 0/3 upstream: reported on 2024/02/18 03:22
upstream INFO: task hung in rtnetlink_rcv_msg net C inconclusive inconclusive 1970 7d10h 1970d 27/27 fixed on 2024/07/09 19:14
linux-6.1 INFO: task hung in __netlink_dump_start 16 24d 169d 0/3 upstream: reported on 2024/01/28 21:16

Sample crash report:
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Interface deactivated: batadv_slave_1
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
INFO: task syz-executor.2:30008 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D27968 30008   8120 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_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1016 [inline]
 __mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
 __netlink_dump_start+0x103/0x6f0 net/netlink/af_netlink.c:2305
 netlink_dump_start include/linux/netlink.h:213 [inline]
 rtnetlink_rcv_msg+0x71e/0xb80 net/core/rtnetlink.c:4745
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2463
 netlink_unicast_kernel net/netlink/af_netlink.c:1325 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1351
 netlink_sendmsg+0x6c3/0xc50 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:661
 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227
 __sys_sendmsg net/socket.c:2265 [inline]
 __do_sys_sendmsg net/socket.c:2274 [inline]
 __se_sys_sendmsg net/socket.c:2272 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2272
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f24a0957059
Code: Bad RIP value.
RSP: 002b:00007f249f2cc168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f24a0a69f60 RCX: 00007f24a0957059
RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000005
RBP: 00007f24a09b108d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe0bafc3ef R14: 00007f249f2cc300 R15: 0000000000022000
INFO: task syz-executor.2:30028 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D30072 30028   8120 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_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1016 [inline]
 __mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
 dev_ioctl+0x26b/0xc50 net/core/dev_ioctl.c:512
 sock_ioctl+0x448/0x5d0 net/socket.c:1069
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688
 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705
 __do_sys_ioctl fs/ioctl.c:712 [inline]
 __se_sys_ioctl fs/ioctl.c:710 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f24a0957059
Code: Bad RIP value.
RSP: 002b:00007f249f28a168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f24a0a6a100 RCX: 00007f24a0957059
RDX: 0000000020000580 RSI: 00000000000089f1 RDI: 0000000000000006
RBP: 00007f24a09b108d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe0bafc3ef R14: 00007f249f28a300 R15: 0000000000022000

Showing all locks held in the system:
3 locks held by kworker/0:1/14:
 #0: 000000008eebfec4 ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124
 #1: 0000000007575e65 ((linkwatch_work).work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128
 #2: 00000000ffa71e76 (rtnl_mutex){+.+.}, at: linkwatch_event+0xb/0x60 net/core/link_watch.c:236
1 lock held by khungtaskd/1570:
 #0: 000000007e65b3f4 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
3 locks held by kworker/0:2/3688:
 #0: 000000008eebfec4 ((wq_completion)"events"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124
 #1: 000000007585b830 (deferred_process_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128
 #2: 00000000ffa71e76 (rtnl_mutex){+.+.}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:150
1 lock held by in:imklog/7800:
 #0: 00000000c685222e (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
2 locks held by agetty/7811:
 #0: 00000000580dd09b (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
 #1: 00000000f6fe2cb7 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1950 drivers/tty/n_tty.c:2154
2 locks held by agetty/7812:
 #0: 0000000047f0537f (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272
 #1: 00000000f466ef35 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1950 drivers/tty/n_tty.c:2154
2 locks held by kworker/u4:5/12212:
3 locks held by kworker/0:4/26139:
 #0: 0000000089717abb ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124
 #1: 0000000007ef089e ((addr_chk_work).work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128
 #2: 00000000ffa71e76 (rtnl_mutex){+.+.}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4476
2 locks held by syz-executor.1/29996:
 #0: 00000000ffa71e76 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
 #0: 00000000ffa71e76 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4779
 #1: 000000008081c794 (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline]
 #1: 000000008081c794 (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x4dc/0x6f0 kernel/rcu/tree_exp.h:667
1 lock held by syz-executor.2/30008:
 #0: 00000000ffa71e76 (rtnl_mutex){+.+.}, at: __netlink_dump_start+0x103/0x6f0 net/netlink/af_netlink.c:2305
1 lock held by syz-executor.2/30028:
 #0: 00000000ffa71e76 (rtnl_mutex){+.+.}, at: dev_ioctl+0x26b/0xc50 net/core/dev_ioctl.c:512

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

NMI backtrace for cpu 0
CPU: 0 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-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: 29996 Comm: syz-executor.1 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ret_from_intr+0x0/0x1e
Code: 3a 00 00 eb 25 66 66 2e 0f 1f 84 00 00 00 00 00 66 66 2e 0f 1f 84 00 00 00 00 00 48 83 04 24 80 e8 16 ff ff ff e8 21 0c 00 00 <fa> 0f 1f 44 00 00 e8 4c 33 e0 f8 5c 65 ff 0c 25 54 df 01 00 f6 84
RSP: 0018:ffff8880ba107ff8 EFLAGS: 00000092
RAX: ffff88804c0a6a78 RBX: 0000000000000000 RCX: ffffffff8151ee73
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888049b06a14
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffed101742455a
R10: ffff8880ba122ad3 R11: ffffffff8c66505b R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007f057742c700(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c025b33598 CR3: 0000000092f30000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 </IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:789 [inline]
RIP: 0010:lock_acquire+0x1ec/0x3c0 kernel/locking/lockdep.c:3911
Code: 08 00 00 00 00 00 00 48 c1 e8 03 80 3c 10 00 0f 85 b7 01 00 00 48 83 3d 09 2e a6 08 00 0f 84 2a 01 00 00 48 8b 7c 24 08 57 9d <0f> 1f 44 00 00 48 83 c4 18 5b 5d 41 5c 41 5d 41 5e 41 5f c3 65 8b
RSP: 0018:ffff88804c0a6b20 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff13e3051 RBX: ffff888049b061c0 RCX: 0000000000002390
RDX: dffffc0000000000 RSI: 00000000fc95a9c7 RDI: 0000000000000286
RBP: ffffffff89e62400 R08: ffffffff8cd291c0 R09: 0000000000000001
R10: ffff888049b06a70 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001
 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline]
 _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:144
 spin_lock include/linux/spinlock.h:329 [inline]
 nf_conntrack_lock net/netfilter/nf_conntrack_core.c:91 [inline]
 get_next_corpse net/netfilter/nf_conntrack_core.c:1896 [inline]
 nf_ct_iterate_cleanup+0x1dc/0x520 net/netfilter/nf_conntrack_core.c:1930
 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2015 [inline]
 nf_ct_iterate_cleanup_net+0x113/0x170 net/netfilter/nf_conntrack_core.c:2000
 masq_device_event+0xd6/0x110 net/ipv4/netfilter/nf_nat_masquerade_ipv4.c:100
 notifier_call_chain+0xc0/0x230 kernel/notifier.c:93
 call_netdevice_notifiers net/core/dev.c:1762 [inline]
 __dev_notify_flags+0x1da/0x2b0 net/core/dev.c:7719
 dev_change_flags+0xf0/0x140 net/core/dev.c:7753
 do_setlink+0x14f1/0x3540 net/core/rtnetlink.c:2449
 rtnl_group_changelink net/core/rtnetlink.c:2925 [inline]
 rtnl_newlink+0xbc9/0x15c0 net/core/rtnetlink.c:3083
 rtnetlink_rcv_msg+0x453/0xb80 net/core/rtnetlink.c:4782
 netlink_rcv_skb+0x160/0x440 net/netlink/af_netlink.c:2463
 netlink_unicast_kernel net/netlink/af_netlink.c:1325 [inline]
 netlink_unicast+0x4d5/0x690 net/netlink/af_netlink.c:1351
 netlink_sendmsg+0x6c3/0xc50 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xc3/0x120 net/socket.c:661
 ___sys_sendmsg+0x7bb/0x8e0 net/socket.c:2227
 __sys_sendmsg net/socket.c:2265 [inline]
 __do_sys_sendmsg net/socket.c:2274 [inline]
 __se_sys_sendmsg net/socket.c:2272 [inline]
 __x64_sys_sendmsg+0x132/0x220 net/socket.c:2272
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f0578ab7059
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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f057742c168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f0578bc9f60 RCX: 00007f0578ab7059
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 00007f0578b1108d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff3a46c73f R14: 00007f057742c300 R15: 0000000000022000
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	00 00                	add    %al,(%rax)
   2:	eb 25                	jmp    0x29
   4:	66 66 2e 0f 1f 84 00 	data16 nopw %cs:0x0(%rax,%rax,1)
   b:	00 00 00 00
   f:	66 66 2e 0f 1f 84 00 	data16 nopw %cs:0x0(%rax,%rax,1)
  16:	00 00 00 00
  1a:	48 83 04 24 80       	addq   $0xffffffffffffff80,(%rsp)
  1f:	e8 16 ff ff ff       	callq  0xffffff3a
  24:	e8 21 0c 00 00       	callq  0xc4a
* 29:	fa                   	cli <-- trapping instruction
  2a:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
  2f:	e8 4c 33 e0 f8       	callq  0xf8e03380
  34:	5c                   	pop    %rsp
  35:	65 ff 0c 25 54 df 01 	decl   %gs:0x1df54
  3c:	00
  3d:	f6                   	.byte 0xf6
  3e:	84                   	.byte 0x84

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/02/25 14:03 linux-4.19.y 3f8a27f9e27b 7c337266 .config console log report info ci2-linux-4-19 INFO: task hung in __netlink_dump_start
* Struck through repros no longer work on HEAD.