syzbot

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BUG: KCSAN: data-race in poll_schedule_timeout.constprop.0 / pollwake

write to 0xffffc900057a3c20 of 4 bytes by task 2743 on cpu 0:
 __pollwake fs/select.c:197 [inline]
 pollwake+0xe6/0x140 fs/select.c:217
 __wake_up_common+0x76/0x180 kernel/sched/wait.c:93
 __wake_up_common_lock+0x77/0xb0 kernel/sched/wait.c:123
 unix_dgram_peer_wake_relay+0xdf/0x170 net/unix/af_unix.c:373
 __wake_up_common+0x76/0x180 kernel/sched/wait.c:93
 __wake_up_common_lock+0x77/0xb0 kernel/sched/wait.c:123
 unix_dgram_recvmsg+0x28f/0xbf0 net/unix/af_unix.c:2135
 sock_recvmsg_nosec net/socket.c:886 [inline]
 ____sys_recvmsg+0x343/0x350 net/socket.c:2583
 ___sys_recvmsg+0xb2/0x100 net/socket.c:2627
 do_recvmmsg+0x17a/0x540 net/socket.c:2725
 __sys_recvmmsg+0x1f1/0x200 net/socket.c:2804
 __do_sys_recvmmsg net/socket.c:2827 [inline]
 __se_sys_recvmmsg net/socket.c:2820 [inline]
 __x64_sys_recvmmsg+0x82/0xb0 net/socket.c:2820
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffffc900057a3c20 of 4 bytes by task 2747 on cpu 1:
 poll_schedule_timeout.constprop.0+0x4c/0xc0 fs/select.c:242
 do_poll fs/select.c:951 [inline]
 do_sys_poll+0x670/0x990 fs/select.c:1001
 __do_sys_ppoll fs/select.c:1101 [inline]
 __se_sys_ppoll fs/select.c:1081 [inline]
 __x64_sys_ppoll+0x156/0x190 fs/select.c:1081
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 2747 Comm: syz-executor.3 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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