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

From: Tom Zanussi
Date: Mon Mar 04 2019 - 19:02:32 EST


On Mon, 2019-03-04 at 18:45 -0500, Steven Rostedt wrote:
> 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.
>

OK, will add that too.

Tom


> -- Steve