syzbot


INFO: rcu detected stall in wg_packet_handshake_receive_worker (3)

Status: upstream: reported syz repro on 2025/05/04 19:10
Subsystems: wireguard
[Documentation on labels]
Reported-by: syzbot+48f45f6dd79ca20c3283@syzkaller.appspotmail.com
First crash: 55d, last: 13h41m
Discussions (2)
Title Replies (including bot) Last reply
[syzbot] Monthly wireguard report (May 2025) 0 (1) 2025/05/12 06:34
[syzbot] [wireguard?] INFO: rcu detected stall in wg_packet_handshake_receive_worker (3) 0 (1) 2025/05/04 19:10
Similar bugs (7)
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 250d 718d 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 309d 309d 0/3 auto-obsoleted due to no activity on 2024/10/19 08:12
linux-5.15 INFO: rcu detected stall in wg_packet_handshake_receive_worker (2) 1 132d 132d 0/3 auto-obsoleted due to no activity on 2025/04/14 22:49
upstream INFO: rcu detected stall in wg_packet_handshake_receive_worker (2) wireguard 1 570d 570d 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 673d 1569d 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 322d 318d 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 249d 249d 0/2 auto-obsoleted due to no activity on 2024/12/08 09:12
Last patch testing requests (1)
Created Duration User Patch Repo Result
2025/05/16 16:57 2h19m retest repro upstream report log

Sample crash report:
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (3 ticks this GP) idle=f5e4/1/0x4000000000000000 softirq=17502/17502 fqs=0
rcu: 	(detected by 1, t=10503 jiffies, g=8145, q=1636 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5843 Comm: kworker/0:3 Not tainted 6.15.0-rc4-syzkaller-00147-gebd297a2affa #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
Workqueue: wg-kex-wg0 wg_packet_handshake_receive_worker
RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:89 [inline]
RIP: 0010:memory_is_nonzero mm/kasan/generic.c:104 [inline]
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:129 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x105/0x1a0 mm/kasan/generic.c:189
Code: 75 0a b8 01 00 00 00 45 3a 11 7c 0b 44 89 c2 e8 61 ec ff ff 83 f0 01 5b 5d 41 5c c3 cc cc cc cc 48 85 d2 74 4f 48 01 ea eb 09 <48> 83 c0 01 48 39 d0 74 41 80 38 00 74 f2 eb b2 41 bc 08 00 00 00
RSP: 0018:ffffc90000007d00 EFLAGS: 00000046
RAX: ffffed100f465a10 RBX: ffffed100f465a11 RCX: ffffffff89808340
RDX: ffffed100f465a11 RSI: 0000000000000004 RDI: ffff88807a32d080
RBP: ffffed100f465a10 R08: 0000000000000001 R09: ffffed100f465a10
R10: ffff88807a32d083 R11: 0000000000000000 R12: 0000000000000000
R13: ffff88807a32d000 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881249e2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000560c50fa2060 CR3: 0000000029abe000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 instrument_atomic_write include/linux/instrumented.h:82 [inline]
 atomic_set include/linux/atomic/atomic-instrumented.h:67 [inline]
 taprio_set_budgets+0x1a0/0x310 net/sched/sch_taprio.c:672
 advance_sched+0x5f6/0xc80 net/sched/sch_taprio.c:977
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_interrupt+0x397/0x8e0 kernel/time/hrtimer.c:1887
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline]
 __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1055
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5870
Code: ce 0b 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 42 ea ec 0e 0f 82 74 02 00 00 8b 35 da 19 ed 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 19 ce 0b 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc90003537850 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e588130 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffffffff8dbbb25f RDI: ffffffff8bf47e20
RBP: 0000000000000002 R08: 52b2bffd12c8faba R09: ffffffff968457c8
R10: 0000000000000004 R11: 0000000000002bc0 R12: 0000000000000001
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 srcu_lock_acquire include/linux/srcu.h:161 [inline]
 srcu_read_lock include/linux/srcu.h:253 [inline]
 kasan_quarantine_reduce+0x8e/0x1e0 mm/kasan/quarantine.c:259
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4161 [inline]
 slab_alloc_node mm/slub.c:4210 [inline]
 __kmalloc_cache_noprof+0x1f1/0x3e0 mm/slub.c:4367
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 keypair_create drivers/net/wireguard/noise.c:100 [inline]
 wg_noise_handshake_begin_session+0xe5/0xe80 drivers/net/wireguard/noise.c:827
 wg_packet_send_handshake_response+0x216/0x310 drivers/net/wireguard/send.c:96
 wg_receive_handshake_packet+0x247/0xbf0 drivers/net/wireguard/receive.c:154
 wg_packet_handshake_receive_worker+0x17f/0x3a0 drivers/net/wireguard/receive.c:213
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g8145 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=4379
rcu: rcu_preempt kthread starved for 10503 jiffies! g8145 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:28728 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x116f/0x5de0 kernel/sched/core.c:6767
 __schedule_loop kernel/sched/core.c:6845 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6860
 schedule_timeout+0x123/0x290 kernel/time/sleep_timeout.c:99
 rcu_gp_fqs_loop+0x1ea/0xb00 kernel/rcu/tree.c:2046
 rcu_gp_kthread+0x270/0x380 kernel/rcu/tree.c:2248
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/05/02 11:32 upstream ebd297a2affa 51b137cd .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in wg_packet_handshake_receive_worker
2025/05/16 17:16 upstream fee3e843b309 cfde8269 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in wg_packet_handshake_receive_worker
2025/04/25 11:25 upstream 02ddfb981de8 e3715315 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in wg_packet_handshake_receive_worker
2025/03/22 18:21 upstream 88d324e69ea9 c6512ef7 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root INFO: rcu detected stall in wg_packet_handshake_receive_worker
* Struck through repros no longer work on HEAD.