syzbot


INFO: rcu detected stall in wg_packet_handshake_receive_worker (2)

Status: upstream: reported on 2025/01/04 22:49
Reported-by: syzbot+ee2e60ca346c0aac392d@syzkaller.appspotmail.com
First crash: 10d, last: 10d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 BUG: soft lockup in wg_packet_handshake_receive_worker origin:upstream C error 7 128d 596d 0/3 upstream: reported C repro on 2023/05/29 21:30
linux-5.15 INFO: rcu detected stall in wg_packet_handshake_receive_worker 1 188d 188d 0/3 auto-obsoleted due to no activity on 2024/10/19 08:12
upstream INFO: rcu detected stall in wg_packet_handshake_receive_worker (2) wireguard 1 448d 448d 0/28 auto-obsoleted due to no activity on 2024/01/22 15:31
upstream INFO: rcu detected stall in wg_packet_handshake_receive_worker wireguard C error inconclusive 3 551d 1447d 0/28 auto-obsoleted due to no activity on 2023/10/21 23:48
upstream BUG: soft lockup in wg_packet_handshake_receive_worker wireguard 1 200d 196d 0/28 auto-obsoleted due to no activity on 2024/09/26 23:05
android-5-15 BUG: soft lockup in wg_packet_handshake_receive_worker origin:lts syz 1 127d 127d 0/2 auto-obsoleted due to no activity on 2024/12/08 09:12

Sample crash report:
wdm_int_callback: 118 callbacks suppressed
cdc_wdm 2-1:1.0: nonzero urb status received: -71
wdm_int_callback: 118 callbacks suppressed
cdc_wdm 2-1:1.0: wdm_int_callback - 0 bytes
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3547/1:b..l
	(detected by 0, t=10502 jiffies, g=14993, q=597)
task:udevd           state:R  running task     stack:24856 pid: 3547 ppid:     1 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549
 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574
 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34
 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
 _raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194
 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
 __wake_up_common_lock kernel/sched/wait.c:140 [inline]
 __wake_up_sync_key+0x121/0x1c0 kernel/sched/wait.c:205
 sock_def_readable+0x135/0x240 net/core/sock.c:3092
 __netlink_sendskb net/netlink/af_netlink.c:1258 [inline]
 netlink_sendskb+0x8e/0x120 net/netlink/af_netlink.c:1264
 netlink_unicast+0x3a1/0x980 net/netlink/af_netlink.c:1352
 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1905
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2436
 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2490
 __sys_sendmsg net/socket.c:2519 [inline]
 __do_sys_sendmsg net/socket.c:2528 [inline]
 __se_sys_sendmsg+0x19a/0x260 net/socket.c:2526
 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: 0033:0x7f815cd64a4b
RSP: 002b:00007ffcb3c23ca8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00005582a02dc9e0 RCX: 00007f815cd64a4b
RDX: 0000000000000000 RSI: 00007ffcb3c23cb8 RDI: 0000000000000004
RBP: 00005582a02fb400 R08: 0000000000000001 R09: 0000000000000000
R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000000b4 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 2095 jiffies! g14993 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=8996
rcu: rcu_preempt kthread starved for 2096 jiffies! g14993 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:27256 pid:   15 ppid:     2 flags:0x00004000
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_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 4370 Comm: kworker/0:9 Not tainted 5.15.175-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: wg-kex-wg1 wg_packet_handshake_receive_worker
Call Trace:
 <IRQ>
 __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_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 kernel/rcu/tree_stall.h:592
 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline]
 rcu_pending kernel/rcu/tree.c:3932 [inline]
 rcu_sched_clock_irq+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1688 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:check_kcov_mode kernel/kcov.c:174 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x2c/0x60 kernel/kcov.c:206
Code: 04 24 65 48 8b 0d d4 ea 81 7e 65 8b 15 d5 ea 81 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 34 16 00 00 00 74 2c <8b> 91 10 16 00 00 83 fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 48
RSP: 0018:ffffc90002ffefd8 EFLAGS: 00000246
RAX: ffffffff8889fc76 RBX: ffff8880602b42d8 RCX: ffff88801e013b80
RDX: 0000000000000000 RSI: 00000000c1050782 RDI: 0000000000000001
RBP: ffffc90002fff178 R08: ffffffff8889fccf R09: fffffbfff2131250
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8880602b42e8
R13: ffff8880602b42d0 R14: ffff8880602b42c0 R15: dffffc0000000000
 fq_dequeue+0x746/0x1fd0 net/sched/sch_fq.c:551
 dequeue_skb net/sched/sch_generic.c:292 [inline]
 qdisc_restart net/sched/sch_generic.c:397 [inline]
 __qdisc_run+0x253/0x1e90 net/sched/sch_generic.c:415
 __dev_xmit_skb net/core/dev.c:3910 [inline]
 __dev_queue_xmit+0xf78/0x32b0 net/core/dev.c:4221
 neigh_hh_output include/net/neighbour.h:493 [inline]
 neigh_output include/net/neighbour.h:507 [inline]
 ip_finish_output2+0xcd7/0x11a0 net/ipv4/ip_output.c:228
 iptunnel_xmit+0x513/0x950 net/ipv4/ip_tunnel_core.c:82
 udp_tunnel_xmit_skb+0x1d0/0x2d0 net/ipv4/udp_tunnel_core.c:175
 send4+0x94a/0xf50 drivers/net/wireguard/socket.c:85
 wg_socket_send_skb_to_peer+0xd1/0x1d0 drivers/net/wireguard/socket.c:175
 wg_packet_send_handshake_response+0x194/0x2d0 drivers/net/wireguard/send.c:103
 wg_receive_handshake_packet drivers/net/wireguard/receive.c:161 [inline]
 wg_packet_handshake_receive_worker+0x619/0xe00 drivers/net/wireguard/receive.c:220
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/01/04 22:49 linux-5.15.y 91786f140358 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan INFO: rcu detected stall in wg_packet_handshake_receive_worker
* Struck through repros no longer work on HEAD.