=============================
WARNING: suspicious RCU usage
6.9.0-rc6-syzkaller-00133-g19e35f24750d #0 Not tainted
-----------------------------
net/bridge/br_private.h:1599 suspicious rcu_dereference_protected() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
6 locks held by kworker/u8:4/61:
#0: ffff888015ecd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3242 [inline]
#0: ffff888015ecd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x17c0 kernel/workqueue.c:3348
#1: ffffc900015c7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3243 [inline]
#1: ffffc900015c7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x17c0 kernel/workqueue.c:3348
#2: ffffffff8f59a350 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594
#3: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
#3: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
#3: ffffffff8e334da0 (rcu_read_lock){....}-{1:2}, at: inet_twsk_purge+0x133/0xa50 net/ipv4/inet_timewait_sock.c:277
#4: ffffc90000007c00 ((&p->forward_delay_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x650 kernel/time/timer.c:1790
#5: ffff88807b9b4cb8 (&br->lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
#5: ffff88807b9b4cb8 (&br->lock){+.-.}-{2:2}, at: br_forward_delay_timer_expired+0x50/0x440 net/bridge/br_stp_timer.c:86
stack backtrace:
CPU: 0 PID: 61 Comm: kworker/u8:4 Not tainted 6.9.0-rc6-syzkaller-00133-g19e35f24750d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: netns cleanup_net
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6712
nbp_vlan_group net/bridge/br_private.h:1599 [inline]
br_mst_set_state+0x1ea/0x650 net/bridge/br_mst.c:105
br_set_state+0x28a/0x7b0 net/bridge/br_stp.c:47
br_forward_delay_timer_expired+0x176/0x440 net/bridge/br_stp_timer.c:88
call_timer_fn+0x18e/0x650 kernel/time/timer.c:1793
expire_timers kernel/time/timer.c:1844 [inline]
__run_timers kernel/time/timer.c:2418 [inline]
__run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2429
run_timer_base kernel/time/timer.c:2438 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2448
__do_softirq+0x2c6/0x980 kernel/softirq.c:554
invoke_softirq kernel/softirq.c:428 [inline]
__irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633
irq_exit_rcu+0x9/0x30 kernel/softirq.c:645
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5758
Code: 2b 00 74 08 4c 89 f7 e8 6a 2c 88 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25
RSP: 0018:ffffc900015c7820 EFLAGS: 00000206
RAX: 0000000000000001 RBX: 1ffff920002b8f10 RCX: 0000000000000001
RDX: dffffc0000000000 RSI: ffffffff8bcaca20 RDI: ffffffff8c1f7ee0
RBP: ffffc900015c7968 R08: ffffffff92f35507 R09: 1ffffffff25e6aa0
R10: dffffc0000000000 R11: fffffbfff25e6aa1 R12: 1ffff920002b8f0c
R13: dffffc0000000000 R14: ffffc900015c7880 R15: 0000000000000246
rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
rcu_read_lock include/linux/rcupdate.h:781 [inline]
inet_twsk_purge+0x154/0xa50 net/ipv4/inet_timewait_sock.c:277
ops_exit_list net/core/net_namespace.c:178 [inline]
cleanup_net+0x89d/0xcc0 net/core/net_namespace.c:640
process_one_work kernel/workqueue.c:3267 [inline]
process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3348
worker_thread+0x86d/0xd70 kernel/workqueue.c:3429
kthread+0x2f0/0x390 kernel/kthread.c:388
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
bridge0: port 1(bridge_slave_0) entered learning state
bridge0: port 2(bridge_slave_1) entered learning state
----------------
Code disassembly (best guess):
0: 2b 00 sub (%rax),%eax
2: 74 08 je 0xc
4: 4c 89 f7 mov %r14,%rdi
7: e8 6a 2c 88 00 call 0x882c76
c: f6 44 24 61 02 testb $0x2,0x61(%rsp)
11: 0f 85 85 01 00 00 jne 0x19c
17: 41 f7 c7 00 02 00 00 test $0x200,%r15d
1e: 74 01 je 0x21
20: fb sti
21: 48 c7 44 24 40 0e 36 movq $0x45e0360e,0x40(%rsp)
28: e0 45
* 2a: 4b c7 44 25 00 00 00 movq $0x0,0x0(%r13,%r12,1) <-- trapping instruction
31: 00 00
33: 43 c7 44 25 09 00 00 movl $0x0,0x9(%r13,%r12,1)
3a: 00 00
3c: 43 rex.XB
3d: c7 .byte 0xc7
3e: 44 rex.R
3f: 25 .byte 0x25