syzbot

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BUG: KCSAN: data-race in file_update_time / inode_update_timestamps

write to 0xffff888106951b50 of 8 bytes by task 11972 on cpu 0:
 inode_set_ctime_to_ts include/linux/fs.h:1626 [inline]
 inode_set_ctime_current fs/inode.c:2515 [inline]
 inode_update_timestamps+0xb5/0x280 fs/inode.c:1861
 generic_update_time fs/inode.c:1900 [inline]
 inode_update_time fs/inode.c:1920 [inline]
 __file_update_time fs/inode.c:2109 [inline]
 file_update_time+0x22f/0x2c0 fs/inode.c:2139
 pipe_write+0xa87/0xd30 fs/pipe.c:607
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x771/0x8e0 fs/read_write.c:590
 ksys_write+0xeb/0x1b0 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:652
 do_syscall_64+0xd3/0x1d0
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

read to 0xffff888106951b50 of 8 bytes by task 11977 on cpu 1:
 inode_get_ctime include/linux/fs.h:1620 [inline]
 inode_needs_update_time fs/inode.c:2092 [inline]
 file_update_time+0x107/0x2c0 fs/inode.c:2135
 pipe_write+0xa87/0xd30 fs/pipe.c:607
 call_write_iter include/linux/fs.h:2110 [inline]
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0x771/0x8e0 fs/read_write.c:590
 ksys_write+0xeb/0x1b0 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __x64_sys_write+0x42/0x50 fs/read_write.c:652
 do_syscall_64+0xd3/0x1d0
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

value changed: 0x0000000012385d1b -> 0x0000000012c533ca

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 11977 Comm: syz-executor.0 Tainted: G        W          6.9.0-rc3-syzkaller-00011-g20cb38a7af88 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
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