linux-kernel - Re: [PATCH 01/14] tools lib traceevent: Get rid of malloc_or_die() in show

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20131209142350.5d23108c@gandalf.local.home>
Date:	Mon, 9 Dec 2013 14:23:50 -0500
From:	Steven Rostedt <rostedt@...dmis.org>
To:	Arnaldo Carvalho de Melo <acme@...stprotocols.net>
Cc:	Namhyung Kim <namhyung@...nel.org>,
	Frederic Weisbecker <fweisbec@...il.com>,
	Ingo Molnar <mingo@...nel.org>, Jiri Olsa <jolsa@...hat.com>,
	LKML <linux-kernel@...r.kernel.org>,
	Namhyung Kim <namhyung.kim@....com>
Subject: Re: [PATCH 01/14] tools lib traceevent: Get rid of malloc_or_die()
 in show_error()

On Mon, 9 Dec 2013 16:14:39 -0300
Arnaldo Carvalho de Melo <acme@...stprotocols.net> wrote:

> Em Mon, Dec 09, 2013 at 02:03:42PM -0500, Steven Rostedt escreveu:
> > On Mon, 9 Dec 2013 15:30:09 -0300
> > Arnaldo Carvalho de Melo <acme@...stprotocols.net> wrote:
> > 
> > 
> > > > +		error = malloc(MAX_ERR_STR_SIZE);
> > > > +		if (error == NULL) {
> > > > +			/* no memory */
> > > > +			*error_str = "failed to allocate memory";
> > > > +			return;
> > > 
> > > Can *error_str point to either malloc'ed or constant strings? Who
> > > releases the allocated memory?
> > > 
> > 
> > Good question. Perhaps we should have a flag that states if the string
> > is allocated or not. Or better yet, since the only reason it would be
> > pointing to a static string is if the string for error_str itself
> > failed to allocate. Then we could use a string within pevent for it:
> > 
> > static char *pevent_failed_error_alloc = "failed to allocate memory";
> > 
> > Then in the freeing of error str:
> > 
> > void pevent_free_error_str(error_str)
> > {
> > 	if (error_str != pevent_failed_error_alloc)
> > 		free(error_str);
> > }
> 
> That is a possibility, yes, then any other routine that works in such a
> way could check against this string, but what is wrong with returning a
> value to that function and checking against < 0?

Then everyone has to check if show_error() failed. Then report a bug if
it did. Egad, then we need to check if that error function failed, and
then that one and that one and that one :-)

-- Steve
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/