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BUG: KCSAN: data-race in do_sendfile / ksys_write

write to 0xffff88810cdaa068 of 8 bytes by task 4597 on cpu 1:
 ksys_write+0x11c/0x1a0 fs/read_write.c:721
 __do_sys_write fs/read_write.c:730 [inline]
 __se_sys_write fs/read_write.c:727 [inline]
 __x64_sys_write+0x40/0x50 fs/read_write.c:727
 x64_sys_call+0x154e/0x2550 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x121/0x390 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

write to 0xffff88810cdaa068 of 8 bytes by task 4599 on cpu 0:
 do_sendfile+0x44c/0x640 fs/read_write.c:1369
 __do_sys_sendfile64 fs/read_write.c:1412 [inline]
 __se_sys_sendfile64 fs/read_write.c:1398 [inline]
 __x64_sys_sendfile64+0x105/0x150 fs/read_write.c:1398
 x64_sys_call+0x1015/0x2550 arch/x86/include/generated/asm/syscalls_64.h:41
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x121/0x390 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x0000000000000000 -> 0x0000000000e08e80

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4599 Comm: syz.3.333 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
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