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BUG: KCSAN: data-race in __inet6_lookup_established / inet_put_port

write to 0xffff88810344a90e of 2 bytes by task 6663 on cpu 1:
 __inet_put_port net/ipv4/inet_hashtables.c:227 [inline]
 inet_put_port+0x197/0x640 net/ipv4/inet_hashtables.c:247
 tcp_set_state net/ipv4/tcp.c:3002 [inline]
 __tcp_close+0x5d4/0x1130 net/ipv4/tcp.c:3170
 tcp_close+0x28/0xd0 net/ipv4/tcp.c:3298
 inet_release+0xce/0xf0 net/ipv4/af_inet.c:437
 inet6_release+0x3e/0x60 net/ipv6/af_inet6.c:487
 __sock_release net/socket.c:662 [inline]
 sock_close+0x6b/0x150 net/socket.c:1455
 __fput+0x29b/0x650 fs/file_table.c:468
 ____fput+0x1c/0x30 fs/file_table.c:496
 task_work_run+0x131/0x1a0 kernel/task_work.c:227
 get_signal+0xe12/0xf70 kernel/signal.c:2807
 arch_do_signal_or_restart+0x96/0x440 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x77/0x110 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810344a90c of 4 bytes by interrupt on cpu 0:
 inet6_match include/net/inet6_hashtables.h:178 [inline]
 __inet6_lookup_established+0x463/0x670 net/ipv6/inet6_hashtables.c:76
 __inet6_lookup include/net/inet6_hashtables.h:92 [inline]
 __inet6_lookup_skb include/net/inet6_hashtables.h:160 [inline]
 tcp_v6_rcv+0x807/0x1d40 net/ipv6/tcp_ipv6.c:1796
 ip6_protocol_deliver_rcu+0xa17/0x10d0 net/ipv6/ip6_input.c:438
 ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500
 dst_input include/net/dst.h:474 [inline]
 ip6_rcv_finish+0x1fa/0x340 net/ipv6/ip6_input.c:79
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ipv6_rcv+0x72/0x150 net/ipv6/ip6_input.c:311
 __netif_receive_skb_one_core net/core/dev.c:6079 [inline]
 __netif_receive_skb+0x9e/0x270 net/core/dev.c:6192
 process_backlog+0x229/0x420 net/core/dev.c:6544
 __napi_poll+0x66/0x310 net/core/dev.c:7594
 napi_poll net/core/dev.c:7657 [inline]
 net_rx_action+0x423/0x8c0 net/core/dev.c:7784
 handle_softirqs+0xba/0x290 kernel/softirq.c:622
 do_softirq+0x5d/0x90 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:936 [inline]
 __dev_queue_xmit+0x1200/0x2000 net/core/dev.c:4790
 dev_queue_xmit include/linux/netdevice.h:3365 [inline]
 neigh_hh_output include/net/neighbour.h:531 [inline]
 neigh_output include/net/neighbour.h:545 [inline]
 ip6_finish_output2+0xa32/0xd10 net/ipv6/ip6_output.c:136
 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]
 ip6_finish_output+0x3a4/0x540 net/ipv6/ip6_output.c:220
 NF_HOOK_COND include/linux/netfilter.h:307 [inline]
 ip6_output+0x10a/0x250 net/ipv6/ip6_output.c:247
 dst_output include/net/dst.h:464 [inline]
 NF_HOOK include/linux/netfilter.h:318 [inline]
 ip6_xmit+0x8f3/0xc40 net/ipv6/ip6_output.c:371
 inet6_csk_xmit+0x217/0x260 net/ipv6/inet6_connection_sock.c:120
 __tcp_transmit_skb+0x14cd/0x1c10 net/ipv4/tcp_output.c:1628
 tcp_transmit_skb net/ipv4/tcp_output.c:1646 [inline]
 tcp_write_xmit+0x129c/0x30f0 net/ipv4/tcp_output.c:2999
 __tcp_push_pending_frames+0x6d/0x1b0 net/ipv4/tcp_output.c:3182
 tcp_sendmsg_locked+0x1cb2/0x2c00 net/ipv4/tcp.c:1354
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1413
 inet6_sendmsg+0x76/0xd0 net/ipv6/af_inet6.c:659
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x8b/0x180 net/socket.c:742
 __sys_sendto+0x268/0x330 net/socket.c:2244
 __do_sys_sendto net/socket.c:2251 [inline]
 __se_sys_sendto net/socket.c:2247 [inline]
 __x64_sys_sendto+0x76/0x90 net/socket.c:2247
 x64_sys_call+0x2d14/0x3000 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x4e22daeb -> 0x0000daeb

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 6660 Comm: wÞ£ÿ Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
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