=============================
WARNING: suspicious RCU usage
6.0.0-rc1-syzkaller-00067-g573ae4f13f63 #0 Not tainted
-----------------------------
include/net/sock.h:592 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
7 locks held by syz-executor.0/3944:
 #0: ffffffff8d7b1f88
 (sock_diag_mutex){+.+.}-{3:3}, at: sock_diag_rcv+0x17/0x40 net/core/sock_diag.c:276
 #1: ffffffff8d7b2108 (sock_diag_table_mutex){+.+.}-{3:3}, at: __sock_diag_cmd net/core/sock_diag.c:230 [inline]
 #1: ffffffff8d7b2108 (sock_diag_table_mutex){+.+.}-{3:3}, at: sock_diag_rcv_msg+0x19b/0x440 net/core/sock_diag.c:266
 #2: ffffffff8d92a5c8 (inet_diag_table_mutex){+.+.}-{3:3}, at: inet_diag_lock_handler+0x6e/0x100 net/ipv4/inet_diag.c:63
 #3: ffff88806508c930 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1687 [inline]
 #3: ffff88806508c930 (sk_lock-AF_INET6){+.+.}-{0:0}, at: udp_abort+0x1f/0xd0 net/ipv4/udp.c:2906
 #4: ffffc90000c59328 (&table->hash[i].lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline]
 #4: ffffc90000c59328 (&table->hash[i].lock){+...}-{2:2}, at: udp_lib_rehash+0x200/0x600 net/ipv4/udp.c:2050
 #5: ffffffff8d7b3078 (reuseport_lock){+...}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:354 [inline]
 #5: ffffffff8d7b3078 (reuseport_lock){+...}-{2:2}, at: reuseport_detach_sock+0x22/0x4a0 net/core/sock_reuseport.c:346
 #6: ffff88806508cbb8 (clock-AF_INET6){++..}-{2:2}, at: bpf_sk_reuseport_detach+0x26/0x190 kernel/bpf/reuseport_array.c:26

stack backtrace:
CPU: 0 PID: 3944 Comm: syz-executor.0 Not tainted 6.0.0-rc1-syzkaller-00067-g573ae4f13f63 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 __rcu_dereference_sk_user_data_with_flags include/net/sock.h:592 [inline]
 bpf_sk_reuseport_detach+0x156/0x190 kernel/bpf/reuseport_array.c:27
 reuseport_detach_sock+0x8c/0x4a0 net/core/sock_reuseport.c:362
 udp_lib_rehash+0x234/0x600 net/ipv4/udp.c:2052
 __udp_disconnect+0x3c3/0x580 net/ipv4/udp.c:1983
 udp_abort+0xaf/0xd0 net/ipv4/udp.c:2916
 sock_diag_destroy+0xcf/0x120 net/core/sock_diag.c:306
 __udp_diag_destroy.isra.0+0x4a5/0xb40 net/ipv4/udp_diag.c:218
 inet_diag_cmd_exact+0x2a8/0x2f0 net/ipv4/inet_diag.c:618
 inet_diag_handler_cmd+0x165/0x2c0 net/ipv4/inet_diag.c:1345
 __sock_diag_cmd net/core/sock_diag.c:237 [inline]
 sock_diag_rcv_msg+0x2e7/0x440 net/core/sock_diag.c:266
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501
 sock_diag_rcv+0x26/0x40 net/core/sock_diag.c:277
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:734
 sock_write_iter+0x291/0x3d0 net/socket.c:1108
 call_write_iter include/linux/fs.h:2187 [inline]
 do_iter_readv_writev+0x20b/0x3b0 fs/read_write.c:729
 do_iter_write+0x182/0x700 fs/read_write.c:855
 vfs_writev+0x1aa/0x630 fs/read_write.c:928
 do_writev+0x279/0x2f0 fs/read_write.c:971
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fe500689279
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe5018bd168 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007fe50079bf80 RCX: 00007fe500689279
RDX: 0000000000000001 RSI: 0000000020000180 RDI: 0000000000000003
RBP: 00007fe5006e3189 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff756f3aff R14: 00007fe5018bd300 R15: 0000000000022000
 </TASK>