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BUG: KCSAN: data-race in tipc_poll / tipc_sk_proto_rcv

read-write to 0xffff888104471b86 of 2 bytes by task 8949 on cpu 0:
 tipc_sk_conn_proto_rcv net/tipc/socket.c:1367 [inline]
 tipc_sk_proto_rcv+0x672/0xb70 net/tipc/socket.c:2156
 tipc_sk_filter_rcv+0x18ed/0x1a20 net/tipc/socket.c:2350
 tipc_sk_enqueue net/tipc/socket.c:2443 [inline]
 tipc_sk_rcv+0x48b/0x1020 net/tipc/socket.c:2495
 tipc_node_xmit+0x234/0x8b0 net/tipc/node.c:1701
 tipc_node_xmit_skb+0x99/0xd0 net/tipc/node.c:1766
 tipc_sk_send_ack+0x265/0x280 net/tipc/socket.c:1824
 tipc_recvstream+0x3b2/0x7e0 net/tipc/socket.c:2093
 sock_recvmsg_nosec net/socket.c:1017 [inline]
 sock_recvmsg+0x13f/0x170 net/socket.c:1039
 ____sys_recvmsg+0xfb/0x290 net/socket.c:2786
 ___sys_recvmsg net/socket.c:2828 [inline]
 __sys_recvmsg+0x1c7/0x270 net/socket.c:2861
 __do_sys_recvmsg net/socket.c:2867 [inline]
 __se_sys_recvmsg net/socket.c:2864 [inline]
 __x64_sys_recvmsg+0x46/0x50 net/socket.c:2864
 x64_sys_call+0xc6d/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:48
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888104471b86 of 2 bytes by task 8955 on cpu 1:
 tsk_conn_cong net/tipc/socket.c:222 [inline]
 tipc_poll+0x1f6/0x360 net/tipc/socket.c:806
 sock_poll+0x22d/0x250 net/socket.c:1379
 vfs_poll include/linux/poll.h:82 [inline]
 __io_arm_poll_handler+0x1e5/0xd40 io_uring/poll.c:583
 io_arm_poll_handler+0x4b0/0x5f0 io_uring/poll.c:708
 io_queue_async+0x8a/0x460 io_uring/io_uring.c:1947
 io_queue_sqe io_uring/io_uring.c:1976 [inline]
 io_req_task_submit+0xb9/0xc0 io_uring/io_uring.c:1369
 io_poll_task_func+0x74e/0xa70 io_uring/poll.c:-1
 io_handle_tw_list+0xce/0x1d0 io_uring/io_uring.c:1057
 tctx_task_work_run+0x6e/0x1c0 io_uring/io_uring.c:1121
 tctx_task_work+0x44/0x80 io_uring/io_uring.c:1139
 task_work_run+0x13c/0x1b0 kernel/task_work.c:227
 get_signal+0xee2/0x1080 kernel/signal.c:2807
 arch_do_signal_or_restart+0x9a/0x4b0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x62/0x120 kernel/entry/common.c:218
 do_syscall_64+0xd6/0x1c0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0234 -> 0x01b2

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 8955 Comm: syz.0.1795 Not tainted 6.15.0-rc1-syzkaller-00288-ge618ee89561b #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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