Re: [PATCH v2] ksmbd: vfs: skip lock-range check on equal size to avoid size==0 underflow

[Namjae Jeon]

On Sun, Nov 9, 2025 at 12:57 AM Qianchang Zhao <pioooooooooip@xxxxxxxxx> wrote:
>
> When size equals the current i_size (including 0), the code used to call
> check_lock_range(filp, i_size, size - 1, WRITE), which computes `size - 1`
> and can underflow for size==0. Skip the equal case.
>
> Reported-by: Qianchang Zhao <pioooooooooip@xxxxxxxxx>
> Reported-by: Zhitong Liu <liuzhitong1993@xxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Qianchang Zhao <pioooooooooip@xxxxxxxxx>
Applied it to #ksmbd-for-next-next.
Thanks!