Re: [PATCH v4 2/5] connector: use __get_task_comm in proc_comm_connector

[Steven Rostedt]

On Thu, 14 Oct 2021 09:48:09 +0800
Yafang Shao <laoar.shao@xxxxxxxxx> wrote:

> > __get_task_comm() uses strncpy() which my understanding is, does not add
> > the nul terminating byte when truncating. Which changes the functionality
> > here. As all task comms have a terminating byte, the old method would copy
> > that and include it. This won't add the terminating byte if the buffer is
> > smaller than the comm, and that might cause issues.
> >  
> 
> Right, that is a problem.
> It seems that we should add a new helper get_task_comm_may_truncated().

Or simply change __get_task_comm() to:

char *__get_task_comm(char *buf, size_t buf_size, struct task_struct *tsk)
{
	task_lock(tsk);
	strncpy(buf, tsk->comm, buf_size);
	/* The copied value is always nul terminated */
	buf[buf_size - 1] = '\0';
	task_unlock(tsk);
	return buf;
}

But that should probably be a separate patch.

-- Steve