Re: [PATCH v4 1/3] exec: Remove obsolete comments

Yafang Shao
2025-05-22T06:18:45Z

On Wed, May 21, 2025 at 2:24 PM Bhupesh <bhupesh@igalia.com> wrote:
>
> Patch 3a3f61ce5e0b ("exec: Make sure task->comm is always NUL-terminated"),
> replaced 'strscpy_pad()' with 'memcpy()' implementations inside
> '__set_task_comm()'.
>
> However a few left-over comments are still there, which mention
> the usage of 'strscpy_pad()' inside '__set_task_comm()'.
>
> Remove those obsolete comments.
>
> While at it, also remove an obsolete comment regarding 'task_lock()'
> usage while handing 'task->comm'.
>
> Signed-off-by: Bhupesh <bhupesh@igalia.com>

Acked-by: Yafang Shao <laoar.shao@gmail.com>

> ---
> include/linux/sched.h | 6 ++----
> 1 file changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/include/linux/sched.h b/include/linux/sched.h
> index 8c60a42f9d00..704222114dcc 100644
> --- a/include/linux/sched.h
> +++ b/include/linux/sched.h
> @@ -1162,10 +1162,8 @@ struct task_struct {
> *
> * - normally initialized begin_new_exec()
> * - set it with set_task_comm()
> - * - strscpy_pad() to ensure it is always NUL-terminated and
> + * - logic inside set_task_comm() will ensure it is always NUL-terminated and
> * zero-padded
> - * - task_lock() to ensure the operation is atomic and the name is
> - * fully updated.
> */
> char comm[TASK_COMM_LEN];
>
> @@ -1997,7 +1995,7 @@ extern void __set_task_comm(struct task_struct *tsk, const char *from, bool exec
> * User space can randomly change their names anyway, so locking for readers
> * doesn't make sense. For writers, locking is probably necessary, as a race
> * condition could lead to long-term mixed results.
> - * The strscpy_pad() in __set_task_comm() can ensure that the task comm is
> + * The logic inside __set_task_comm() should ensure that the task comm is
> * always NUL-terminated and zero-padded. Therefore the race condition between
> * reader and writer is not an issue.
> *
> --
> 2.38.1
>

--
Regards
Yafang