=============================
WARNING: suspicious RCU usage
syzkaller #0 Not tainted
-----------------------------
net/xfrm/xfrm_user.c:1630 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz.0.17/5833:
 #0: ffff888032dcc390 (&net->xfrm.xfrm_cfg_mutex){+.+.}-{4:4}, at: xfrm_netlink_rcv+0x62/0x90 net/xfrm/xfrm_user.c:3928

stack backtrace:
CPU: 1 UID: 0 PID: 5833 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 lockdep_rcu_suspicious.cold+0x4f/0xb1 kernel/locking/lockdep.c:6876
 xfrm_nlmsg_multicast net/xfrm/xfrm_user.c:1630 [inline]
 xfrm_send_migrate_state net/xfrm/xfrm_user.c:3340 [inline]
 xfrm_do_migrate_state+0x2463/0x2f10 net/xfrm/xfrm_user.c:3507
 xfrm_user_rcv_msg+0x483/0xd80 net/xfrm/xfrm_user.c:3907
 netlink_rcv_skb+0x159/0x420 net/netlink/af_netlink.c:2556
 xfrm_netlink_rcv+0x71/0x90 net/xfrm/xfrm_user.c:3929
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x585/0x850 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:775 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 ____sys_sendmsg+0xa4d/0xbe0 net/socket.c:2684
 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2738
 __sys_sendmsg+0x160/0x210 net/socket.c:2770
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9a1659de99
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe88741d08 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9a16825fa0 RCX: 00007f9a1659de99
RDX: 0000000000000000 RSI: 0000200000000500 RDI: 0000000000000003
RBP: 00007f9a16633eaf R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9a16825fac R14: 00007f9a16825fa0 R15: 00007f9a16825fa0
 </TASK>