syzbot

=============================
WARNING: suspicious RCU usage
6.10.0-rc3-syzkaller-00755-ga012f9a752a5 #0 Not tainted
-----------------------------
net/netfilter/ipset/ip_set_core.c:1200 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
3 locks held by kworker/u8:5/989:
 #0: ffff888015edd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff888015edd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90004667d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90004667d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8f5da110 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594

stack backtrace:
CPU: 1 PID: 989 Comm: kworker/u8:5 Not tainted 6.10.0-rc3-syzkaller-00755-ga012f9a752a5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 __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
 _destroy_all_sets+0x232/0x5f0 net/netfilter/ipset/ip_set_core.c:1200
 ip_set_net_exit+0x20/0x50 net/netfilter/ipset/ip_set_core.c:2396
 ops_exit_list net/core/net_namespace.c:173 [inline]
 cleanup_net+0x802/0xcc0 net/core/net_namespace.c:640
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>