syzbot


INFO: task hung in genl_rcv_msg (2)

Status: auto-obsoleted due to no activity on 2023/10/06 17:32
Subsystems: net
[Documentation on labels]
First crash: 332d, last: 298d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in genl_rcv_msg (3) net C done 13 29d 172d 0/26 closed as invalid on 2024/04/16 10:15
linux-4.19 INFO: task hung in genl_rcv_msg syz error 17 450d 1826d 0/1 upstream: reported syz repro on 2019/05/02 15:34
upstream INFO: task hung in genl_rcv_msg syz done error 648 478d 2026d 0/26 auto-obsoleted due to no activity on 2023/05/10 03:30
linux-4.14 INFO: task hung in genl_rcv_msg (2) 6 1261d 1450d 0/1 auto-closed as invalid on 2021/03/17 23:44
linux-6.1 INFO: task hung in genl_rcv_msg 1 137d 137d 0/3 auto-obsoleted due to no activity on 2024/03/26 09:02
linux-4.14 INFO: task hung in genl_rcv_msg syz done 2 1566d 1566d 1/1 fixed on 2020/02/16 23:53
linux-5.15 INFO: task hung in genl_rcv_msg 1 274d 274d 0/3 auto-obsoleted due to no activity on 2023/11/09 20:26

Sample crash report:
INFO: task syz-executor.0:11968 blocked for more than 143 seconds.
      Not tainted 6.4.0-syzkaller-12365-g8689f4f2ea56 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:24696 pid:11968 ppid:1      flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5381 [inline]
 __schedule+0xc9a/0x5880 kernel/sched/core.c:6710
 schedule+0xde/0x1a0 kernel/sched/core.c:6786
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6845
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0xa3b/0x1350 kernel/locking/mutex.c:747
 genl_lock net/netlink/genetlink.c:33 [inline]
 genl_rcv_msg+0x51a/0x7e0 net/netlink/genetlink.c:1065
 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2549
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1078
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:748
 __sys_sendto+0x254/0x350 net/socket.c:2134
 __do_sys_sendto net/socket.c:2146 [inline]
 __se_sys_sendto net/socket.c:2142 [inline]
 __x64_sys_sendto+0xe1/0x1b0 net/socket.c:2142
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4f87a3e2ac
RSP: 002b:00007ffcecbb8a50 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f4f886d4620 RCX: 00007f4f87a3e2ac
RDX: 0000000000000020 RSI: 00007f4f886d4670 RDI: 0000000000000005
RBP: 0000000000000000 R08: 00007ffcecbb8aa4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffcecbb8af8
R13: 00007f4f886d4670 R14: 0000000000000005 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8c9a0ab0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:522
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8c9a07b0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:522
1 lock held by khungtaskd/27:
 #0: ffffffff8c9a16c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x340 kernel/locking/lockdep.c:6615
2 locks held by getty/4765:
 #0: ffff88802905c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900020282f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xf08/0x13f0 drivers/tty/n_tty.c:2187
3 locks held by syz-executor.0/11849:
2 locks held by syz-executor.0/11968:
 #0: ffffffff8e45ef90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1077
 #1: ffffffff8e45f048 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
 #1: ffffffff8e45f048 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x51a/0x7e0 net/netlink/genetlink.c:1065
2 locks held by syz-executor.0/11977:
 #0: ffffffff8e45ef90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1077
 #1: ffffffff8e45f048 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
 #1: ffffffff8e45f048 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x51a/0x7e0 net/netlink/genetlink.c:1065
2 locks held by syz-executor.0/11992:
 #0: ffffffff8e45ef90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1077
 #1: ffffffff8e45f048 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline]
 #1: ffffffff8e45f048 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x51a/0x7e0 net/netlink/genetlink.c:1065

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 6.4.0-syzkaller-12365-g8689f4f2ea56 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x29c/0x350 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x2a4/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xe16/0x1090 kernel/hung_task.c:379
 kthread+0x344/0x440 kernel/kthread.c:389
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 11849 Comm: syz-executor.0 Not tainted 6.4.0-syzkaller-12365-g8689f4f2ea56 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
RIP: 0010:match_held_lock+0xe/0xc0 kernel/locking/lockdep.c:5210
Code: c7 00 60 6c 8a e8 62 5d 2c f7 0f 0b eb 97 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 53 48 89 fb 48 83 ec 08 48 39 77 10 74 6a <66> f7 47 22 e0 ff 74 5a 48 8b 46 08 48 89 f7 48 85 c0 74 42 8b 15
RSP: 0018:ffffc90004a9ebc0 EFLAGS: 00000002
RAX: 0000000000000000 RBX: ffff888038090b88 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8c9a16c0 RDI: ffff888038090b88
RBP: ffffffff8c9a16c0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880380900c0
R13: ffff888038090b88 R14: 00000000ffffffff R15: ffff888038090b88
FS:  00007fa8ca35a700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c008039000 CR3: 000000002a1a9000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 __lock_is_held kernel/locking/lockdep.c:5502 [inline]
 lock_is_held_type+0xab/0x140 kernel/locking/lockdep.c:5832
 __rhashtable_lookup include/linux/rhashtable.h:622 [inline]
 rhashtable_lookup include/linux/rhashtable.h:646 [inline]
 tipc_sk_lookup+0x817/0x910 net/tipc/socket.c:3004
 tipc_nl_publ_dump+0x318/0xca0 net/tipc/socket.c:3815
 __tipc_nl_compat_dumpit+0x2a9/0xb30 net/tipc/netlink_compat.c:223
 tipc_nl_compat_publ_dump net/tipc/netlink_compat.c:1031 [inline]
 tipc_nl_compat_sk_dump+0x4f5/0x8a0 net/tipc/netlink_compat.c:1083
 __tipc_nl_compat_dumpit+0x405/0xb30 net/tipc/netlink_compat.c:234
 tipc_nl_compat_dumpit+0x458/0x810 net/tipc/netlink_compat.c:317
 tipc_nl_compat_handle net/tipc/netlink_compat.c:1257 [inline]
 tipc_nl_compat_recv+0xae5/0xbd0 net/tipc/netlink_compat.c:1320
 genl_family_rcv_msg_doit.isra.0+0x1e6/0x2d0 net/netlink/genetlink.c:970
 genl_family_rcv_msg net/netlink/genetlink.c:1050 [inline]
 genl_rcv_msg+0x4ff/0x7e0 net/netlink/genetlink.c:1067
 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2549
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1078
 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]
 netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365
 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg+0xde/0x190 net/socket.c:748
 ____sys_sendmsg+0x739/0x920 net/socket.c:2494
 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2548
 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2577
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fa8c968c389
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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:00007fa8ca35a168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fa8c97abf80 RCX: 00007fa8c968c389
RDX: 0000000000000000 RSI: 0000000020000500 RDI: 0000000000000004
RBP: 00007fa8c96d7493 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdf6c382ff R14: 00007fa8ca35a300 R15: 0000000000022000
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/07/08 17:27 upstream 8689f4f2ea56 668cb1fa .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in genl_rcv_msg
2023/06/04 21:13 upstream 9561de3a55be a4ae4f42 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: task hung in genl_rcv_msg
* Struck through repros no longer work on HEAD.