linux-kernel - Re: [PATCH] no need for checking it

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]

Date:	Sat, 06 Jun 2009 19:08:19 +0800
From:	"Figo.zhang" <figo1802@...il.com>
To:	Pekka Enberg <penberg@...helsinki.fi>
Cc:	Greg Kroah-Hartman <gregkh@...e.de>,
	Ian Abbott <abbotti@....co.uk>,
	Frank Mori Hess <fmhess@...rs.sourceforge.net>,
	David Schleef <ds@...leef.org>,
	lkml <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] no need for checking it

On Sat, 2009-06-06 at 13:56 +0300, Pekka Enberg wrote:
> On Sat, Jun 6, 2009 at 1:51 PM, Figo.zhang <figo1802@...il.com> wrote:
> > vfree() does it's own NULL checking,so no need for check before
> > calling it.
> >
> > Signed-off-by: Figo.zhang <figo1802@...il.com>
> > ---
> >  drivers/staging/comedi/drivers.c |    6 +++---
> >  1 files changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/staging/comedi/drivers.c
> > b/drivers/staging/comedi/drivers.c
> > index 6e13e45..ce50e85 100644
> > --- a/drivers/staging/comedi/drivers.c
> > +++ b/drivers/staging/comedi/drivers.c
> > @@ -495,9 +495,9 @@ int comedi_buf_alloc(struct comedi_device *dev,
> > struct comedi_subdevice *s,
> >                                vmap(pages, n_pages, VM_MAP,
> >                                PAGE_KERNEL_NOCACHE);
> >                }
> > -               if (pages) {
> > -                       vfree(pages);
> > -               }
> > +               vfree(pages);
> > +               pages = NULL;
> 
> Why the assignment to NULL? It looks redundant to me.
> 
> > +
> >                if (async->prealloc_buf == NULL) {
> >                        /* Some allocation failed above. */
> >                        if (async->buf_page_list) {
> >
> >
> > --
> > 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/
> >

yes, 'pages' is local variable argment,it is no need assignment to NULL.

Best Regards,

Figo.zhang

--
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/