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BUG: KCSAN: data-race in do_select / pollwake

write to 0xffffc9000156fa00 of 4 bytes by interrupt on cpu 1:
 __pollwake fs/select.c:195 [inline]
 pollwake+0xb6/0x100 fs/select.c:215
 __wake_up_common kernel/sched/wait.c:89 [inline]
 __wake_up_common_lock kernel/sched/wait.c:106 [inline]
 __wake_up_sync_key+0x4f/0x80 kernel/sched/wait.c:173
 sock_def_readable+0x70/0x190 net/core/sock.c:3533
 tcp_data_ready+0x1ab/0x290 net/ipv4/tcp_input.c:5250
 tcp_rcv_established+0xce0/0xea0 net/ipv4/tcp_input.c:6279
 tcp_v4_do_rcv+0x672/0x740 net/ipv4/tcp_ipv4.c:1925
 tcp_v4_rcv+0x1bcf/0x1f60 net/ipv4/tcp_ipv4.c:2363
 ip_protocol_deliver_rcu+0x397/0x780 net/ipv4/ip_input.c:205
 ip_local_deliver_finish+0x184/0x220 net/ipv4/ip_input.c:233
 NF_HOOK include/linux/netfilter.h:314 [inline]
 ip_local_deliver+0xe8/0x1c0 net/ipv4/ip_input.c:254
 dst_input include/net/dst.h:469 [inline]
 ip_sublist_rcv_finish net/ipv4/ip_input.c:578 [inline]
 ip_list_rcv_finish net/ipv4/ip_input.c:627 [inline]
 ip_sublist_rcv+0x56b/0x650 net/ipv4/ip_input.c:635
 ip_list_rcv+0x261/0x290 net/ipv4/ip_input.c:669
 __netif_receive_skb_list_ptype net/core/dev.c:5930 [inline]
 __netif_receive_skb_list_core+0x4dc/0x500 net/core/dev.c:5977
 __netif_receive_skb_list net/core/dev.c:6029 [inline]
 netif_receive_skb_list_internal+0x487/0x600 net/core/dev.c:6120
 gro_normal_list include/net/gro.h:532 [inline]
 napi_complete_done+0x1a3/0x410 net/core/dev.c:6490
 virtqueue_napi_complete drivers/net/virtio_net.c:737 [inline]
 virtnet_poll+0x18bf/0x1d00 drivers/net/virtio_net.c:3053
 __napi_poll+0x63/0x3a0 net/core/dev.c:7324
 napi_poll net/core/dev.c:7388 [inline]
 net_rx_action+0x38e/0x7b0 net/core/dev.c:7510
 handle_softirqs+0xb7/0x290 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0x3a/0xc0 kernel/softirq.c:680
 common_interrupt+0x83/0x90 arch/x86/kernel/irq.c:285
 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:693
 kcsan_setup_watchpoint+0x415/0x430 kernel/kcsan/core.c:705
 link_path_walk+0x114/0x8b0 fs/namei.c:2450
 path_lookupat+0x63/0x2a0 fs/namei.c:2659
 filename_lookup+0x147/0x340 fs/namei.c:2689
 vfs_statx+0x9d/0x380 fs/stat.c:350
 vfs_fstatat+0xe1/0x160 fs/stat.c:372
 __do_sys_newfstatat fs/stat.c:536 [inline]
 __se_sys_newfstatat+0x55/0x260 fs/stat.c:530
 __x64_sys_newfstatat+0x55/0x70 fs/stat.c:530
 x64_sys_call+0x2c22/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:263
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc9000156fa00 of 4 bytes by task 3302 on cpu 0:
 poll_schedule_timeout fs/select.c:240 [inline]
 do_select+0xe41/0xf40 fs/select.c:603
 core_sys_select+0x3b2/0x600 fs/select.c:677
 do_pselect fs/select.c:759 [inline]
 __do_sys_pselect6 fs/select.c:802 [inline]
 __se_sys_pselect6+0x216/0x280 fs/select.c:793
 __x64_sys_pselect6+0x78/0x90 fs/select.c:793
 x64_sys_call+0x1caa/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:271
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3302 Comm: syz-executor Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
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