syzbot

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BUG: KCSAN: data-race in tipc_poll / tipc_sk_proto_rcv

read-write to 0xffff888108a6db86 of 2 bytes by task 18094 on cpu 1:
 tipc_sk_conn_proto_rcv net/tipc/socket.c:1372 [inline]
 tipc_sk_proto_rcv+0x657/0xb10 net/tipc/socket.c:2161
 tipc_sk_filter_rcv+0x189f/0x19d0 net/tipc/socket.c:2355
 tipc_sk_backlog_rcv+0x69/0xc0 net/tipc/socket.c:2410
 sk_backlog_rcv include/net/sock.h:1115 [inline]
 __release_sock+0xe5/0x240 net/core/sock.c:2970
 release_sock+0x44/0x110 net/core/sock.c:3507
 __tipc_sendstream+0x46e/0xb20 net/tipc/socket.c:1587
 tipc_sendstream+0x3e/0x60 net/tipc/socket.c:1551
 sock_sendmsg_nosec net/socket.c:725 [inline]
 sock_sendmsg net/socket.c:748 [inline]
 sock_write_iter+0x1aa/0x230 net/socket.c:1129
 call_write_iter include/linux/fs.h:1871 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x4ab/0x7d0 fs/read_write.c:584
 ksys_write+0xeb/0x1a0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888108a6db86 of 2 bytes by task 3167 on cpu 0:
 tsk_conn_cong net/tipc/socket.c:225 [inline]
 tipc_poll+0x1f1/0x350 net/tipc/socket.c:809
 sock_poll+0x253/0x270 net/socket.c:1374
 vfs_poll include/linux/poll.h:88 [inline]
 p9_fd_poll net/9p/trans_fd.c:239 [inline]
 p9_poll_mux net/9p/trans_fd.c:629 [inline]
 p9_poll_workfn+0x24d/0x410 net/9p/trans_fd.c:1167
 process_one_work+0x434/0x860 kernel/workqueue.c:2597
 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2748
 kthread+0x1d7/0x210 kernel/kthread.c:389
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

value changed: 0x0186 -> 0x0001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3167 Comm: kworker/0:4 Not tainted 6.4.0-syzkaller-07208-gc6b0271053e7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Workqueue: events p9_poll_workfn
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