Re: [PATCH] tools lib traceevent: add checks for returned EVENT_ERROR type

Namhyung Kim
2015-08-09T03:13:43Z

On Fri, Aug 07, 2015 at 12:59:10PM +0200, Jiri Olsa wrote:
> On Mon, Aug 03, 2015 at 01:08:05PM -0400, Dean Nelson wrote:
> > The second warning message and SIGSEGV stem from the issue expressed in the
> > first warning message, and are the result of ignoring the EVENT_ERROR type
> > returned back through the call chain.
> >
> > Dealing with the first warning message is beyond the scope of this patch. But
> > the second warning is addressed by this patch's first hunk. And the SIGSEGV is
> > eliminated by its second hunk.
> >
> > Signed-off-by: Dean Nelson <dnelson@redhat.com>
> > ---
> > tools/lib/traceevent/event-parse.c | 5 ++++-
> > 1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
> > index cc25f05..72e2933 100644
> > --- a/tools/lib/traceevent/event-parse.c
> > +++ b/tools/lib/traceevent/event-parse.c
> > @@ -1680,6 +1680,9 @@ process_cond(struct event_format *event, struct print_arg *top, char **tok)
> > type = process_arg(event, left, &token);
> >
> > again:
> > + if (type == EVENT_ERROR)
> > + goto out_free;
> > +
> > /* Handle other operations in the arguments */
> > if (type == EVENT_OP && strcmp(token, ":") != 0) {
> > type = process_op(event, left, &token);
> > @@ -1940,7 +1943,7 @@ process_op(struct event_format *event, struct print_arg *arg, char **tok)
> >
> > type = process_arg_token(event, right, tok, type);
> >
> > - if (right->type == PRINT_OP &&
> > + if (type != EVENT_ERROR && right->type == PRINT_OP &&

I think you'd better put the error check on separate lines. Other
than that look good to me.

Thanks,
Namhyung

> > get_op_prio(arg->op.op) < get_op_prio(right->op.op)) {
> > struct print_arg tmp;
> >