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BUG: KCSAN: data-race in fasync_remove_entry / sock_wake_async

write to 0xffff88811a810058 of 8 bytes by task 6793 on cpu 0:
 fasync_remove_entry+0xcc/0x120 fs/fcntl.c:1016
 fasync_helper+0x97/0xc0 fs/fcntl.c:1115
 sock_fasync+0x58/0xc0 net/socket.c:1480
 __fput+0x5e6/0x650 fs/file_table.c:465
 ____fput+0x1c/0x30 fs/file_table.c:496
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
 exit_to_user_mode_loop+0x1f7/0x6f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x1d3/0x2a0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88811a810058 of 8 bytes by task 6790 on cpu 1:
 sock_wake_async+0x29/0x110 net/socket.c:1495
 sk_wake_async_rcu include/net/sock.h:2570 [inline]
 unix_write_space+0x13b/0x140 net/unix/af_unix.c:607
 sock_wfree+0x149/0x3a0 net/core/sock.c:2693
 unix_destruct_scm+0xcd/0x100 net/unix/af_unix.c:1980
 skb_release_head_state+0x261/0x270 net/core/skbuff.c:1160
 skb_release_all net/core/skbuff.c:1180 [inline]
 __kfree_skb+0x18/0x150 net/core/skbuff.c:1196
 sk_skb_reason_drop+0xbd/0x260 net/core/skbuff.c:1234
 kfree_skb_reason include/linux/skbuff.h:1322 [inline]
 unix_release_sock+0x62e/0x750 net/unix/af_unix.c:726
 unix_release+0x58/0x80 net/unix/af_unix.c:1184
 __sock_release net/socket.c:662 [inline]
 sock_close+0x6b/0x150 net/socket.c:1455
 __fput+0x29b/0x650 fs/file_table.c:468
 ____fput+0x1c/0x30 fs/file_table.c:496
 task_work_run+0x130/0x1a0 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:44 [inline]
 exit_to_user_mode_loop+0x1f7/0x6f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x1d3/0x2a0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0xffff888104b0f7e0 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 6790 Comm: syz.6.763 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
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