=============================
WARNING: suspicious RCU usage
6.8.0-rc3-syzkaller-gf735966ee23c #0 Not tainted
-----------------------------
net/netfilter/ipset/ip_set_hash_gen.h:455 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
2 locks held by syz-executor.0/10405:
 #0: ffff80008ee43fc0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:297
 #1: ffff80008ee44080 (rcu_callback){....}-{0:0}, at: rcu_lock_acquire+0xc/0x3c include/linux/rcupdate.h:297

stack backtrace:
CPU: 1 PID: 10405 Comm: syz-executor.0 Not tainted 6.8.0-rc3-syzkaller-gf735966ee23c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call trace:
 dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
 dump_stack+0x1c/0x28 lib/dump_stack.c:113
 lockdep_rcu_suspicious+0x260/0x464 kernel/locking/lockdep.c:6712
 hash_netportnet6_destroy+0xe0/0x268 net/netfilter/ipset/ip_set_hash_gen.h:455
 ip_set_destroy_set net/netfilter/ipset/ip_set_core.c:1180 [inline]
 ip_set_destroy_set_rcu+0x6c/0xe8 net/netfilter/ipset/ip_set_core.c:1190
 rcu_do_batch kernel/rcu/tree.c:2190 [inline]
 rcu_core+0x890/0x1b34 kernel/rcu/tree.c:2465
 rcu_core_si+0x10/0x1c kernel/rcu/tree.c:2482
 __do_softirq+0x2d8/0xce4 kernel/softirq.c:553
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:81
 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:889
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:86
 invoke_softirq kernel/softirq.c:434 [inline]
 __irq_exit_rcu+0x1d8/0x434 kernel/softirq.c:632
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:644
 __el1_irq arch/arm64/kernel/entry-common.c:503 [inline]
 el1_interrupt+0x38/0x68 arch/arm64/kernel/entry-common.c:517
 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:522
 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:594
 __daif_local_irq_restore arch/arm64/include/asm/irqflags.h:176 [inline]
 arch_local_irq_restore arch/arm64/include/asm/irqflags.h:196 [inline]
 lock_acquire+0x278/0x71c kernel/locking/lockdep.c:5757
 rcu_lock_acquire+0x38/0x44 include/linux/rcupdate.h:298
 rcu_read_lock include/linux/rcupdate.h:750 [inline]
 percpu_ref_put_many include/linux/percpu-refcount.h:330 [inline]
 percpu_ref_put+0x24/0x274 include/linux/percpu-refcount.h:351
 css_put include/linux/cgroup_refcnt.h:79 [inline]
 obj_cgroup_uncharge_pages mm/memcontrol.c:3277 [inline]
 __memcg_kmem_uncharge_page+0x118/0x1e0 mm/memcontrol.c:3348
 memcg_kmem_uncharge_page include/linux/memcontrol.h:1854 [inline]
 exit_task_stack_account+0x164/0x320 kernel/fork.c:560
 do_exit+0x140c/0x1f64 kernel/exit.c:912
 do_group_exit+0x194/0x22c kernel/exit.c:1020
 get_signal+0x1500/0x15ec kernel/signal.c:2893
 do_signal arch/arm64/kernel/signal.c:1249 [inline]
 do_notify_resume+0x3bc/0x393c arch/arm64/kernel/signal.c:1302
 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:137 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:144 [inline]
 el0_svc+0x9c/0x158 arch/arm64/kernel/entry-common.c:679
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598
vkms_vblank_simulate: vblank timer overrun