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BUG: KCSAN: data-race in do_select / pollwake

read to 0xffffc9000c833a50 of 4 bytes by task 27907 on cpu 0:
 poll_schedule_timeout fs/select.c:243 [inline]
 do_select+0xea3/0xf90 fs/select.c:607
 core_sys_select+0x361/0x520 fs/select.c:681
 do_pselect fs/select.c:763 [inline]
 __do_sys_pselect6 fs/select.c:804 [inline]
 __se_sys_pselect6+0x220/0x290 fs/select.c:795
 __x64_sys_pselect6+0x78/0x90 fs/select.c:795
 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

write to 0xffffc9000c833a50 of 4 bytes by interrupt on cpu 1:
 __pollwake fs/select.c:198 [inline]
 pollwake+0xbe/0x110 fs/select.c:218
 __wake_up_common+0xb3/0x130 kernel/sched/wait.c:107
 __wake_up_common_lock kernel/sched/wait.c:138 [inline]
 __wake_up_sync_key+0x82/0xc0 kernel/sched/wait.c:208
 sock_def_readable+0x70/0x1b0 net/core/sock.c:3293
 __udp_enqueue_schedule_skb+0x4e1/0x540 net/ipv4/udp.c:1593
 __udpv6_queue_rcv_skb net/ipv6/udp.c:666 [inline]
 udpv6_queue_rcv_one_skb+0x63d/0xa00 net/ipv6/udp.c:774
 udpv6_queue_rcv_skb+0x2b8/0x2f0 net/ipv6/udp.c:792
 udp6_unicast_rcv_skb+0x16b/0x180 net/ipv6/udp.c:935
 __udp6_lib_rcv+0x7e5/0x940 net/ipv6/udp.c:1020
 udpv6_rcv+0x4f/0x60 net/ipv6/udp.c:1133
 ip6_protocol_deliver_rcu+0x93c/0xf50 net/ipv6/ip6_input.c:439
 ip6_input_finish net/ipv6/ip6_input.c:484 [inline]
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ip6_input+0xbf/0x1b0 net/ipv6/ip6_input.c:493
 dst_input include/net/dst.h:454 [inline]
 ip6_rcv_finish+0x1e2/0x2e0 net/ipv6/ip6_input.c:79
 NF_HOOK include/linux/netfilter.h:302 [inline]
 ipv6_rcv+0x74/0x150 net/ipv6/ip6_input.c:309
 __netif_receive_skb_one_core net/core/dev.c:5479 [inline]
 __netif_receive_skb+0x90/0x1b0 net/core/dev.c:5593
 process_backlog+0x21f/0x380 net/core/dev.c:5921
 __napi_poll+0x60/0x3b0 net/core/dev.c:6482
 napi_poll net/core/dev.c:6549 [inline]
 net_rx_action+0x31a/0x6c0 net/core/dev.c:6659
 __do_softirq+0xc1/0x265 kernel/softirq.c:571
 do_softirq+0x7e/0xb0 kernel/softirq.c:472
 __local_bh_enable_ip+0x64/0x70 kernel/softirq.c:396
 local_bh_enable+0x1f/0x20 include/linux/bottom_half.h:33
 rcu_read_unlock_bh include/linux/rcupdate.h:843 [inline]
 ip6_finish_output2+0x9c4/0xc50 net/ipv6/ip6_output.c:135
 __ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
 ip6_finish_output+0x39a/0x4e0 net/ipv6/ip6_output.c:206
 NF_HOOK_COND include/linux/netfilter.h:291 [inline]
 ip6_output+0xeb/0x220 net/ipv6/ip6_output.c:227
 dst_output include/net/dst.h:444 [inline]
 ip6_local_out+0x64/0x80 net/ipv6/output_core.c:155
 ip6_send_skb+0x47/0x100 net/ipv6/ip6_output.c:1984
 udp_v6_send_skb+0x795/0xbf0 net/ipv6/udp.c:1294
 udpv6_sendmsg+0x137c/0x1540 net/ipv6/udp.c:1586
 inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:651
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg net/socket.c:747 [inline]
 ____sys_sendmsg+0x375/0x4c0 net/socket.c:2501
 ___sys_sendmsg net/socket.c:2555 [inline]
 __sys_sendmmsg+0x263/0x500 net/socket.c:2641
 __do_sys_sendmmsg net/socket.c:2670 [inline]
 __se_sys_sendmmsg net/socket.c:2667 [inline]
 __x64_sys_sendmmsg+0x57/0x60 net/socket.c:2667
 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

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 27917 Comm: syz-executor.4 Not tainted 6.3.0-rc5-syzkaller-00032-g99ddf2254feb #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023
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