syzbot


INFO: task hung in gtp_encap_destroy

Status: auto-obsoleted due to no activity on 2025/04/20 11:30
Subsystems: net
[Documentation on labels]
First crash: 217d, last: 217d

Sample crash report:
INFO: task syz.4.6031:19165 blocked for more than 141 seconds.
      Not tainted 6.13.0-rc7-syzkaller-00116-g4395a44acb15 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.6031      state:D stack:25912 pid:19165 tgid:19165 ppid:5832   flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5369 [inline]
 __schedule+0x1850/0x4c30 kernel/sched/core.c:6756
 __schedule_loop kernel/sched/core.c:6833 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6848
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6905
 __mutex_lock_common kernel/locking/mutex.c:665 [inline]
 __mutex_lock+0x7e7/0xee0 kernel/locking/mutex.c:735
 gtp_encap_destroy+0x12/0x20 drivers/net/gtp.c:867
 udp_destroy_sock+0x227/0x2d0 net/ipv4/udp.c:2837
 sk_common_release+0x71/0x2e0 net/core/sock.c:3824
 inet_release+0x17d/0x200 net/ipv4/af_inet.c:435
 __sock_release net/socket.c:640 [inline]
 sock_close+0xbc/0x240 net/socket.c:1408
 __fput+0x23c/0xa50 fs/file_table.c:450
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x13f/0x340 kernel/entry/common.c:218
 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0f98585d29
RSP: 002b:00007ffd0daf6658 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f0f98777ba0 RCX: 00007f0f98585d29
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f0f98777ba0 R08: 0000000000005cbc R09: 00007ffd0daf694f
R10: 00007f0f98777ac0 R11: 0000000000000246 R12: 000000000005537b
R13: 00007ffd0daf6760 R14: 0000000000000032 R15: ffffffffffffffff
 </TASK>

Showing all locks held in the system:
2 locks held by kthreadd/2:
 #0: ffff8880b873e8d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598
 #1: ffff8880b8728948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41d/0x7a0 kernel/sched/psi.c:987
4 locks held by kworker/0:1/9:
2 locks held by ksoftirqd/0/16:
1 lock held by khungtaskd/30:
 #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e937ae0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744
2 locks held by kswapd1/90:
3 locks held by kworker/u8:5/432:
 #0: ffff88814d2de948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
 #0: ffff88814d2de948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317
 #1: ffffc90003087d00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
 #1: ffffc90003087d00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317
 #2: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4755
3 locks held by kworker/u8:6/2128:
2 locks held by klogd/5194:
1 lock held by udevd/5205:
2 locks held by dhcpcd/5499:
2 locks held by getty/5583:
 #0: ffff8880315190a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
2 locks held by syz-executor/5817:
5 locks held by kworker/u9:2/5831:
 #0: ffff88805c56a148 ((wq_completion)hci6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
 #0: ffff88805c56a148 ((wq_completion)hci6){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317
 #1: ffffc90003e1fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
 #1: ffffc90003e1fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317
 #2: ffff88802aa20d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:331
 #3: ffff88802aa20078 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x1e4/0x11f0 net/bluetooth/hci_sync.c:5585
 #4: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 #4: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976
4 locks held by kworker/u9:3/5834:
 #0: ffff8880285c3948 ((wq_completion)hci7){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
 #0: ffff8880285c3948 ((wq_completion)hci7){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317
 #1: ffffc90003e4fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
 #1: ffffc90003e4fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317
 #2: ffff888035540d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:331
 #3: ffff888035540078 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x1e4/0x11f0 net/bluetooth/hci_sync.c:5585
4 locks held by kworker/u9:4/5836:
 #0: ffff8880226b5948 ((wq_completion)hci5){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
 #0: ffff8880226b5948 ((wq_completion)hci5){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3317
 #1: ffffc90003e6fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
 #1: ffffc90003e6fd00 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3317
 #2: ffff88807be44d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1ec/0x400 net/bluetooth/hci_sync.c:331
 #3: ffff88807be44078 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x1e4/0x11f0 net/bluetooth/hci_sync.c:5585
2 locks held by syz.4.6031/19165:
 #0: ffff88807bb72608 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:818 [inline]
 #0: ffff88807bb72608 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:639 [inline]
 #0: ffff88807bb72608 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1408
 #1: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: gtp_encap_destroy+0x12/0x20 drivers/net/gtp.c:867
1 lock held by syz.1.6034/19172:
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3517
3 locks held by syz.0.6036/19176:
 #0: ffff8880324ccd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:480 [inline]
 #0: ffff8880324ccd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x203/0x510 net/bluetooth/hci_core.c:2697
 #1: ffff8880324cc078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x5c8/0x11c0 net/bluetooth/hci_sync.c:5201
 #2: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline]
 #2: ffffffff8e93cff8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976
1 lock held by syz.2.6038/19180:
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: wext_ioctl_dispatch+0x102/0x530 net/wireless/wext-core.c:1015
2 locks held by syz.3.6050/19206:
 #0: ffffffff8fd159b0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
 #1: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: nl80211_pre_doit+0x5f/0x8b0 net/wireless/nl80211.c:16587
1 lock held by syz-executor/19214:
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline]
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987
1 lock held by syz-executor/19218:
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline]
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987
1 lock held by syz-executor/19220:
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline]
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987
1 lock held by syz-executor/19222:
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline]
 #0: ffffffff8fcb2f48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987
1 lock held by syz-executor/19226:

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc7-syzkaller-00116-g4395a44acb15 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline]
 watchdog+0xff6/0x1040 kernel/hung_task.c:397
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.13.0-rc7-syzkaller-00116-g4395a44acb15 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
RIP: 0010:lockdep_enabled kernel/locking/lockdep.c:116 [inline]
RIP: 0010:lock_is_held_type+0x2c/0x190 kernel/locking/lockdep.c:5914
Code: 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 bb ff ff ff ff 83 3d a4 a8 50 04 00 <0f> 84 00 01 00 00 65 8b 05 87 7c 39 74 85 c0 0f 85 f1 00 00 00 65
RSP: 0018:ffffc90000156d38 EFLAGS: 00000202
RAX: 000fc5fa1d049100 RBX: 00000000ffffffff RCX: 0000000000000100
RDX: ffff88801cacda00 RSI: 00000000ffffffff RDI: ffffffff8e937ae0
RBP: ffff88807c8570b8 R08: ffffffff899ab816 R09: ffffc900001570b0
R10: ffffc900001570a0 R11: fffff5200002ade2 R12: ffff88805d632000
R13: ffff88807c8570cf R14: 1ffff1100f90ae19 R15: 1ffff1100f90ae17
FS:  0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd21e390815 CR3: 0000000075358000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 __in6_dev_get include/net/addrconf.h:330 [inline]
 ip6_ignore_linkdown include/net/addrconf.h:421 [inline]
 find_match+0xf9/0xc10 net/ipv6/route.c:747
 __find_rr_leaf+0x275/0x8e0 net/ipv6/route.c:835
 find_rr_leaf net/ipv6/route.c:856 [inline]
 rt6_select net/ipv6/route.c:900 [inline]
 fib6_table_lookup+0x413/0xbb0 net/ipv6/route.c:2195
 ip6_pol_route+0x273/0x15d0 net/ipv6/route.c:2231
 pol_lookup_func include/net/ip6_fib.h:616 [inline]
 fib6_rule_lookup+0x58c/0x790 net/ipv6/fib6_rules.c:117
 ip6_route_input_lookup net/ipv6/route.c:2300 [inline]
 ip6_route_input+0x859/0xd90 net/ipv6/route.c:2596
 ip6_rcv_finish+0x144/0x180 net/ipv6/ip6_input.c:77
 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314
 __netif_receive_skb_one_core net/core/dev.c:5704 [inline]
 __netif_receive_skb+0x1ea/0x650 net/core/dev.c:5817
 process_backlog+0x662/0x15b0 net/core/dev.c:6149
 __napi_poll+0xcb/0x490 net/core/dev.c:6902
 napi_poll net/core/dev.c:6971 [inline]
 net_rx_action+0x89b/0x1240 net/core/dev.c:7093
 handle_softirqs+0x2d4/0x9b0 kernel/softirq.c:561
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:950
 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/20 11:21 net 4395a44acb15 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce INFO: task hung in gtp_encap_destroy
* Struck through repros no longer work on HEAD.