syzbot


WARNING: suspicious RCU usage in qdisc_lookup

Status: upstream: reported C repro on 2024/10/24 18:40
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+[email protected]
First crash: 230d, last: 25m
Bug presence (2)
Date Name Commit Repro Result
2025/03/15 linux-5.15.y (ToT) 0c935c049b5c C [report] WARNING: suspicious RCU usage in qdisc_lookup
2025/03/15 upstream (ToT) eb88e6bfbc0a C Didn't crash
Fix bisection attempts (1)
Created Duration User Patch Repo Result
2025/04/05 06:31 1h54m fix candidate upstream OK (0) job log

Sample crash report:
=============================
WARNING: suspicious RCU usage
5.15.180-syzkaller #0 Not tainted
-----------------------------
net/sched/sch_api.c:304 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
8 locks held by kworker/0:2/1111:
 #0: ffff88807305e538 ((wq_completion)wg-crypt-wg0){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc900051a7d20 ((work_completion)(&peer->transmit_packet_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff888078480ad8 (&peer->endpoint_lock){++..}-{2:2}, at: wg_socket_send_skb_to_peer+0x56/0x1d0 drivers/net/wireguard/socket.c:173
 #3: ffffffff8cb1f540 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:312
 #4: ffffffff8cb1f540 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:312
 #5: ffffffff8cb1f540 (rcu_read_lock_bh){....}-{1:2}, at: rcu_lock_acquire+0x9/0x30 include/linux/rcupdate.h:312
 #6: ffff888078587908 (&sch->q.lock){+...}-{2:2}, at: spin_lock include/linux/spinlock.h:363 [inline]
 #6: ffff888078587908 (&sch->q.lock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3910 [inline]
 #6: ffff888078587908 (&sch->q.lock){+...}-{2:2}, at: __dev_queue_xmit+0xc1f/0x32b0 net/core/dev.c:4252
 #7: ffffffff8cb1f4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311

stack backtrace:
CPU: 0 PID: 1111 Comm: kworker/0:2 Not tainted 5.15.180-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: wg-crypt-wg0 wg_packet_tx_worker
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 qdisc_lookup+0xa8/0x630 net/sched/sch_api.c:304
 qdisc_tree_reduce_backlog+0x212/0x4f0 net/sched/sch_api.c:800
 sfq_enqueue+0x1214/0x23e0 net/sched/sch_sfq.c:475
 qdisc_enqueue include/net/sch_generic.h:832 [inline]
 tbf_enqueue+0x35d/0x6f0 net/sched/sch_tbf.c:243
 dev_qdisc_enqueue+0x47/0x240 net/core/dev.c:3851
 __dev_xmit_skb net/core/dev.c:3935 [inline]
 __dev_queue_xmit+0xe32/0x32b0 net/core/dev.c:4252
 neigh_hh_output include/net/neighbour.h:493 [inline]
 neigh_output include/net/neighbour.h:507 [inline]
 ip6_finish_output2+0xead/0x15a0 net/ipv6/ip6_output.c:130
 ip6tunnel_xmit include/net/ip6_tunnel.h:160 [inline]
 udp_tunnel6_xmit_skb+0x536/0x970 net/ipv6/ip6_udp_tunnel.c:109
 send6+0x6b8/0xad0 drivers/net/wireguard/socket.c:152
 wg_socket_send_skb_to_peer+0x111/0x1d0 drivers/net/wireguard/socket.c:178
 wg_packet_create_data_done drivers/net/wireguard/send.c:251 [inline]
 wg_packet_tx_worker+0x1a1/0x7a0 drivers/net/wireguard/send.c:276
 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 (5268):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/22 05:19 linux-5.15.y f7347f400572 2a20f901 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/04/09 05:26 linux-5.15.y 0c935c049b5c a775275d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/04/09 01:09 linux-5.15.y 0c935c049b5c a775275d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/04/08 23:49 linux-5.15.y 0c935c049b5c a775275d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/01/28 10:16 linux-5.15.y 003148680b79 18070896 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/02/07 02:19 linux-5.15.y c16c81c81336 8002dd28 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2024/10/27 06:27 linux-5.15.y 74cdd62cb470 65e8686b .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2024/10/26 13:04 linux-5.15.y 74cdd62cb470 65e8686b .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/03/10 04:14 linux-5.15.y c16c81c81336 163f510d .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/02/26 05:47 linux-5.15.y c16c81c81336 d34966d1 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/11 08:00 linux-5.15.y 1c700860e8bc 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/11 08:00 linux-5.15.y 1c700860e8bc 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/10 21:28 linux-5.15.y 1c700860e8bc 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/10 14:44 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/10 12:56 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/08 22:04 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/08 18:34 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/08 09:18 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 23:48 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 20:09 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 17:18 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 09:40 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/06 19:57 linux-5.15.y 1c700860e8bc 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/06 19:52 linux-5.15.y 1c700860e8bc 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING: suspicious RCU usage in qdisc_lookup
2025/06/11 20:51 linux-5.15.y 1c700860e8bc 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/11 14:12 linux-5.15.y 1c700860e8bc 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/11 12:58 linux-5.15.y 1c700860e8bc 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/11 04:47 linux-5.15.y 1c700860e8bc 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/10 23:15 linux-5.15.y 1c700860e8bc 5d7e17ca .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/10 11:00 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/10 06:47 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/10 04:24 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/10 01:49 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/09 19:33 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/09 17:26 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/09 08:31 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/08 23:20 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/08 17:06 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/08 15:44 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/08 14:36 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/08 02:01 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 21:17 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 15:42 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 14:22 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 08:34 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 07:31 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 07:09 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/07 06:07 linux-5.15.y 1c700860e8bc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/06 23:34 linux-5.15.y 1c700860e8bc 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/06 18:19 linux-5.15.y 1c700860e8bc 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/06 16:48 linux-5.15.y 1c700860e8bc 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/06 13:59 linux-5.15.y 1c700860e8bc 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/06 13:35 linux-5.15.y 1c700860e8bc 9fa58bba .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/06 04:16 linux-5.15.y 1c700860e8bc 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/06 01:35 linux-5.15.y 1c700860e8bc 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2025/06/05 14:21 linux-5.15.y 1c700860e8bc 6b6b5f21 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
2024/10/24 18:39 linux-5.15.y 74cdd62cb470 0d144d1a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 WARNING: suspicious RCU usage in qdisc_lookup
* Struck through repros no longer work on HEAD.
OSZAR »