================================================================== BUG: KCSAN: data-race in do_fcntl / vfs_write read-write to 0xffff888139d77c40 of 4 bytes by task 1814 on cpu 1: setfl fs/fcntl.c:80 [inline] do_fcntl+0xc72/0xd30 fs/fcntl.c:339 __do_sys_fcntl fs/fcntl.c:453 [inline] __se_sys_fcntl+0xc6/0x180 fs/fcntl.c:438 __x64_sys_fcntl+0x3f/0x50 fs/fcntl.c:438 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 read to 0xffff888139d77c40 of 4 bytes by task 1815 on cpu 0: iocb_flags include/linux/fs.h:3261 [inline] init_sync_kiocb include/linux/fs.h:2208 [inline] new_sync_write fs/read_write.c:500 [inline] vfs_write+0x3b2/0x890 fs/read_write.c:591 ksys_write+0xe8/0x1a0 fs/read_write.c:644 __do_sys_write fs/read_write.c:656 [inline] __se_sys_write fs/read_write.c:653 [inline] __x64_sys_write+0x3e/0x50 fs/read_write.c:653 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 value changed: 0x00008001 -> 0x0004c801 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 1815 Comm: syz-executor.0 Not tainted 5.19.0-rc5-syzkaller-00056-ge35e5b6f695d-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 ==================================================================