syzbot

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BUG: KCSAN: data-race in do_sys_poll / pollwake

write to 0xffffc9000383fbd0 of 4 bytes by task 27830 on cpu 1:
 __pollwake fs/select.c:198 [inline]
 pollwake+0xbe/0x110 fs/select.c:218
 __wake_up_common kernel/sched/wait.c:89 [inline]
 __wake_up_common_lock kernel/sched/wait.c:106 [inline]
 __wake_up+0x65/0xb0 kernel/sched/wait.c:127
 unix_dgram_peer_wake_relay+0xd4/0xf0 net/unix/af_unix.c:456
 __wake_up_common kernel/sched/wait.c:89 [inline]
 __wake_up_common_lock kernel/sched/wait.c:106 [inline]
 __wake_up_sync_key+0x51/0x80 kernel/sched/wait.c:173
 __unix_dgram_recvmsg+0x3c5/0x900 net/unix/af_unix.c:2456
 unix_dgram_recvmsg+0x81/0x90 net/unix/af_unix.c:2531
 sock_recvmsg_nosec+0x107/0x140 net/socket.c:1046
 ____sys_recvmsg+0x271/0x280 net/socket.c:2801
 ___sys_recvmsg net/socket.c:2845 [inline]
 do_recvmmsg+0x2eb/0x720 net/socket.c:2939
 __sys_recvmmsg net/socket.c:3018 [inline]
 __do_sys_recvmmsg net/socket.c:3041 [inline]
 __se_sys_recvmmsg net/socket.c:3034 [inline]
 __x64_sys_recvmmsg+0xe2/0x170 net/socket.c:3034
 x64_sys_call+0xda3/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffc9000383fbd0 of 4 bytes by task 27831 on cpu 0:
 poll_schedule_timeout fs/select.c:243 [inline]
 do_poll fs/select.c:965 [inline]
 do_sys_poll+0x9b4/0xc10 fs/select.c:1016
 __do_sys_ppoll fs/select.c:1122 [inline]
 __se_sys_ppoll+0x1af/0x1f0 fs/select.c:1102
 __x64_sys_ppoll+0x67/0x80 fs/select.c:1102
 x64_sys_call+0x2c71/0x2d30 arch/x86/include/generated/asm/syscalls_64.h:272
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 27831 Comm: syz-executor.2 Tainted: G        W          6.9.0-rc4-syzkaller-00113-g2668e3ae2ef3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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