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BUG: KCSAN: data-race in inet_csk_complete_hashdance / sk_clone

write to 0xffff8881043b4a40 of 8 bytes by interrupt on cpu 1:
 inet_csk_reqsk_queue_add net/ipv4/inet_connection_sock.c:1410 [inline]
 inet_csk_complete_hashdance+0x522/0x720 net/ipv4/inet_connection_sock.c:1451
 tcp_check_req+0x1195/0x1260 net/ipv4/tcp_minisocks.c:952
 tcp_v4_rcv+0xedb/0x1c50 net/ipv4/tcp_ipv4.c:2166
 ip_protocol_deliver_rcu+0x38c/0x7a0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x1f0/0x2e0 net/ipv4/ip_input.c:241
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip_local_deliver+0xe8/0x1e0 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:481 [inline]
 ip_rcv_finish+0x188/0x1a0 net/ipv4/ip_input.c:492
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip_rcv+0x62/0x160 net/ipv4/ip_input.c:612
 __netif_receive_skb_one_core net/core/dev.c:6212 [inline]
 __netif_receive_skb net/core/dev.c:6325 [inline]
 process_backlog+0x333/0x680 net/core/dev.c:6676
 __napi_poll+0x61/0x300 net/core/dev.c:7735
 napi_poll net/core/dev.c:7798 [inline]
 net_rx_action+0x456/0x930 net/core/dev.c:7955
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 do_softirq+0x45/0x60 kernel/softirq.c:523
 __local_bh_enable_ip+0x70/0x80 kernel/softirq.c:450
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:914 [inline]
 __dev_queue_xmit+0x1360/0x1e90 net/core/dev.c:4913
 dev_queue_xmit include/linux/netdevice.h:3448 [inline]
 neigh_hh_output include/net/neighbour.h:544 [inline]
 neigh_output include/net/neighbour.h:558 [inline]
 ip_finish_output2+0x752/0x8a0 net/ipv4/ip_output.c:236
 __ip_finish_output net/ipv4/ip_output.c:-1 [inline]
 ip_finish_output+0x112/0x290 net/ipv4/ip_output.c:324
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip_output+0xbd/0x1c0 net/ipv4/ip_output.c:437
 dst_output include/net/dst.h:471 [inline]
 ip_local_out net/ipv4/ip_output.c:131 [inline]
 __ip_queue_xmit+0xb4c/0xb80 net/ipv4/ip_output.c:533
 ip_queue_xmit+0x39/0x50 net/ipv4/ip_output.c:547
 __tcp_transmit_skb+0x1c4f/0x20f0 net/ipv4/tcp_output.c:1717
 tcp_transmit_skb net/ipv4/tcp_output.c:1734 [inline]
 tcp_write_xmit+0x17f7/0x3630 net/ipv4/tcp_output.c:3062
 __tcp_push_pending_frames+0x6d/0x1b0 net/ipv4/tcp_output.c:3245
 tcp_push+0x308/0x320 net/ipv4/tcp.c:772
 tcp_sendmsg_locked+0x24b8/0x2c70 net/ipv4/tcp.c:1414
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1451
 inet_sendmsg+0x76/0xd0 net/ipv4/af_inet.c:865
 sock_sendmsg_nosec net/socket.c:776 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 sock_sendmsg+0x1b9/0x220 net/socket.c:813
 rds_tcp_xmit+0x415/0x650 net/rds/tcp_send.c:125
 rds_send_xmit+0x781/0x1680 net/rds/send.c:425
 rds_send_worker+0x44/0x1b0 net/rds/threads.c:200
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3405
 worker_thread+0x569/0x750 kernel/workqueue.c:3486
 kthread+0x221/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff8881043b4684 of 2428 bytes by interrupt on cpu 0:
 sock_copy net/core/sock.c:2227 [inline]
 sk_clone+0xb3/0xa10 net/core/sock.c:2491
 sk_clone_lock include/net/sock.h:1848 [inline]
 inet_csk_clone_lock+0x28/0x270 net/ipv4/inet_connection_sock.c:1208
 tcp_create_openreq_child+0x30/0x1270 net/ipv4/tcp_minisocks.c:550
 tcp_v4_syn_recv_sock+0xbe/0xa60 net/ipv4/tcp_ipv4.c:1697
 tcp_v6_syn_recv_sock+0xa8/0xbf0 net/ipv6/tcp_ipv6.c:1405
 tcp_check_req+0xeb0/0x1260 net/ipv4/tcp_minisocks.c:934
 tcp_v4_rcv+0xedb/0x1c50 net/ipv4/tcp_ipv4.c:2166
 ip_protocol_deliver_rcu+0x38c/0x7a0 net/ipv4/ip_input.c:207
 ip_local_deliver_finish+0x1f0/0x2e0 net/ipv4/ip_input.c:241
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip_local_deliver+0xe8/0x1e0 net/ipv4/ip_input.c:262
 dst_input include/net/dst.h:481 [inline]
 ip_rcv_finish+0x188/0x1a0 net/ipv4/ip_input.c:492
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip_rcv+0x62/0x160 net/ipv4/ip_input.c:612
 __netif_receive_skb_one_core net/core/dev.c:6212 [inline]
 __netif_receive_skb net/core/dev.c:6325 [inline]
 process_backlog+0x333/0x680 net/core/dev.c:6676
 __napi_poll+0x61/0x300 net/core/dev.c:7735
 napi_poll net/core/dev.c:7798 [inline]
 net_rx_action+0x456/0x930 net/core/dev.c:7955
 handle_softirqs+0xb9/0x280 kernel/softirq.c:622
 do_softirq+0x45/0x60 kernel/softirq.c:523
 __local_bh_enable_ip+0x70/0x80 kernel/softirq.c:450
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:914 [inline]
 __dev_queue_xmit+0x1360/0x1e90 net/core/dev.c:4913
 dev_queue_xmit include/linux/netdevice.h:3448 [inline]
 neigh_hh_output include/net/neighbour.h:544 [inline]
 neigh_output include/net/neighbour.h:558 [inline]
 ip_finish_output2+0x752/0x8a0 net/ipv4/ip_output.c:236
 __ip_finish_output net/ipv4/ip_output.c:-1 [inline]
 ip_finish_output+0x112/0x290 net/ipv4/ip_output.c:324
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip_output+0xbd/0x1c0 net/ipv4/ip_output.c:437
 dst_output include/net/dst.h:471 [inline]
 ip_local_out net/ipv4/ip_output.c:131 [inline]
 __ip_queue_xmit+0xb4c/0xb80 net/ipv4/ip_output.c:533
 ip_queue_xmit+0x39/0x50 net/ipv4/ip_output.c:547
 __tcp_transmit_skb+0x1c4f/0x20f0 net/ipv4/tcp_output.c:1717
 tcp_transmit_skb net/ipv4/tcp_output.c:1734 [inline]
 tcp_write_xmit+0x17f7/0x3630 net/ipv4/tcp_output.c:3062
 __tcp_push_pending_frames+0x6d/0x1b0 net/ipv4/tcp_output.c:3245
 tcp_push+0x308/0x320 net/ipv4/tcp.c:772
 tcp_sendmsg_locked+0x24b8/0x2c70 net/ipv4/tcp.c:1414
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1451
 inet_sendmsg+0x76/0xd0 net/ipv4/af_inet.c:865
 sock_sendmsg_nosec net/socket.c:776 [inline]
 __sock_sendmsg net/socket.c:790 [inline]
 sock_sendmsg+0x1b9/0x220 net/socket.c:813
 rds_tcp_xmit+0x415/0x650 net/rds/tcp_send.c:125
 rds_send_xmit+0x781/0x1680 net/rds/send.c:425
 rds_send_worker+0x44/0x1b0 net/rds/threads.c:200
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3405
 worker_thread+0x569/0x750 kernel/workqueue.c:3486
 kthread+0x221/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 49 Comm: kworker/u8:3 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: krds_cp_wq#3/0 rds_send_worker
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