Re: [PATCH 2/2] tracing: Fix kmemleak in set_trigger_filter

From: Steven Rostedt
Date: Wed Aug 23 2017 - 22:16:01 EST


On Wed, 23 Aug 2017 18:58:03 -0400 (EDT)
Chunyu Hu <chuhu@xxxxxxxxxx> wrote:

> ----- Original Message -----
> > From: "Steven Rostedt" <rostedt@xxxxxxxxxxx>
> > To: "Chunyu Hu" <chuhu@xxxxxxxxxx>
> > Cc: mingo@xxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx
> > Sent: Wednesday, August 23, 2017 12:52:49 PM
> > Subject: Re: [PATCH 2/2] tracing: Fix kmemleak in set_trigger_filter
> >
> > On Wed, 23 Aug 2017 10:41:55 -0400
> > Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
> >
> > > * On success, returns 0 and *@filterp points to the new filter. On
> > > * failure, returns -errno and *@filterp may point to %NULL or to a new
> > > * filter. In the latter case, the returned filter contains error
> > > * information if @set_str is %true and the caller is responsible for
> > > * freeing it.
> > >
> > > So filter contains an error string when it fails. It seems that we
> > > should somehow propagate that up the chain to display. I'll look more
> > > into this.
> >
> > The bug is in create_filter(), because "set_str" is set to false, and
> > the filter should not be passed back allocated on error.
>
> Thanks for all the analysis. I think you are right. I'll try to have a test on it
> in case we miss something. But please don't block on my test.
>

My tests are almost done, but I wont send anything till tomorrow. I can
wait a day to post. There's a few other changes I need to send to Linus
as well.

-- Steve