Re: [PATCH] tracing: prefer strlcpy to strncpy

From: Steven Rostedt
Date: Mon Jun 04 2018 - 14:10:11 EST


On Tue, 29 May 2018 18:55:23 -0700
Nick Desaulniers <nick.desaulniers@xxxxxxxxx> wrote:

> On Mon, May 28, 2018 at 11:03 PM, Nick Desaulniers
> <nick.desaulniers@xxxxxxxxx> wrote:
> > Fixes a stringop-truncation warning from gcc-8.
> >
> > Signed-off-by: Nick Desaulniers <nick.desaulniers@xxxxxxxxx>
> > ---
> > kernel/trace/trace_events_hist.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
> > index b9061ed..b53a6c0 100644
> > --- a/kernel/trace/trace_events_hist.c
> > +++ b/kernel/trace/trace_events_hist.c
> > @@ -393,7 +393,7 @@ static void hist_err_event(char *str, char *system, char *event, char *var)
> > else if (system)
> > snprintf(err, MAX_FILTER_STR_VAL, "%s.%s", system, event);
> > else
> > - strncpy(err, var, MAX_FILTER_STR_VAL);
> > + strlcpy(err, var, MAX_FILTER_STR_VAL);
> >
> > hist_err(str, err);
> > }
> > --
> > 2.7.4
> >
>
> Eric points out this wont initialize the rest of err with zeros.

And why do we care?

-- Steve