Re: [PATCH 2/2] tracing: Use strncpy instead of memcpy for string keys in hist triggers

From: Steven Rostedt
Date: Mon Mar 04 2019 - 18:45:37 EST


On Mon, 04 Mar 2019 16:31:40 -0600
Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx> wrote:

> > Hmm, I don't think it's really necessary - it's not used in a key so
> > don't care about anything after the null, and TASK_COMM_LEN is used
> > in
> > the memcpy.
>
> Never mind, yeah, it would make sense to do this, will create another
> patch...

And probably should change the memcpy() of comm in kernel/trace/trace.c
too. It could be that memcpy() is a little bit faster than strncpy(),
and this is done on scheduling switches when tracing is active, but
still, I'm starting to think that isn't a good choice.

-- Steve