Re: [PATCH v4 1/4] bootconfig: init: Fix memblock leak in xbc_make_cmdline()

[Masami Hiramatsu]

On Wed, 6 Oct 2021 21:02:16 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> On Thu, 16 Sep 2021 15:23:12 +0900
> Masami Hiramatsu <mhiramat@xxxxxxxxxx> wrote:
> 
> > Free unused memblock in a error case to fix memblock leak
> > in xbc_make_cmdline().
> > 
> > Fixes: 51887d03aca1 ("bootconfig: init: Allow admin to use bootconfig for kernel command line")
> > Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> > ---
> >  init/main.c |    1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/init/main.c b/init/main.c
> > index 3f7216934441..0b054fff8e92 100644
> > --- a/init/main.c
> > +++ b/init/main.c
> > @@ -382,6 +382,7 @@ static char * __init xbc_make_cmdline(const char *key)
> >  	ret = xbc_snprint_cmdline(new_cmdline, len + 1, root);
> >  	if (ret < 0 || ret > len) {
> >  		pr_err("Failed to print extra kernel cmdline.\n");
> > +		memblock_free_ptr(new_cmdline, len + 1);
> >  		return NULL;
> >  	}
> >  
> 
> Hmm, looking at my patch queue, I noticed that this did not get
> applied. I'm thinking I may have been confused with the other memory
> freeing that was put into the xbc_destroy(), thinking this was part of
> that. But now that I look at this patch in the context of the code, it
> looks like this patch is required, as "new_cmdline" never gets exposed
> on this error.
> 
> Masami, I just want to confirm, that this patch is still relevant, right?

Yes, with other 2 patches in this series ([1/4]-[3/4]), I thought you already
queued it in your tree as you said in [1];

> I'm going to leave this patch out, and just review and accept the first three patches
> in the series.

[1] https://lore.kernel.org/all/20210916164805.32592423@xxxxxxxxxxxxxxxxxx/T/#u

So, my next cleanup series [2] (including xbc_destroy_all() -> xbc_exit()) was
based on the [1]'s first 3 patches.

[2] https://lore.kernel.org/all/163187294400.2366983.7393164788107844569.stgit@devnote2/T/#u

If it helps, I can make these series to one series and rebase on top of your
for-next (or ftrace/core) branch.


Thank you,

> 
> Thanks!
> 
> -- Steve


-- 
Masami Hiramatsu <mhiramat@xxxxxxxxxx>