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BUG: KCSAN: data-race in file_end_write / posix_acl_update_mode

write to 0xffff888118513aa0 of 2 bytes by task 16080 on cpu 1:
 posix_acl_update_mode+0x220/0x250 fs/posix_acl.c:720
 simple_set_acl+0x6c/0x120 fs/posix_acl.c:1022
 set_posix_acl fs/posix_acl.c:954 [inline]
 vfs_set_acl+0x581/0x720 fs/posix_acl.c:1133
 do_set_acl+0xab/0x130 fs/posix_acl.c:1278
 do_setxattr fs/xattr.c:633 [inline]
 filename_setxattr+0x1f1/0x2b0 fs/xattr.c:665
 path_setxattrat+0x28a/0x320 fs/xattr.c:713
 __do_sys_setxattr fs/xattr.c:747 [inline]
 __se_sys_setxattr fs/xattr.c:743 [inline]
 __x64_sys_setxattr+0x6e/0x90 fs/xattr.c:743
 x64_sys_call+0x28e7/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:189
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888118513aa0 of 2 bytes by task 16073 on cpu 0:
 file_end_write+0x1f/0x110 include/linux/fs.h:3059
 vfs_fallocate+0x3a5/0x3b0 fs/open.c:350
 ksys_fallocate fs/open.c:362 [inline]
 __do_sys_fallocate fs/open.c:367 [inline]
 __se_sys_fallocate fs/open.c:365 [inline]
 __x64_sys_fallocate+0x78/0xc0 fs/open.c:365
 x64_sys_call+0x295f/0x2e10 arch/x86/include/generated/asm/syscalls_64.h:286
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x8000 -> 0x8072

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 16073 Comm: syz.6.3255 Not tainted 6.15.0-rc1-syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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