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Subject: Re: [Bug #15589] 2.6.34-rc1: Badness at fs/proc/generic.c:316
From: Michael Ellerman <michael@ellerman.id.au>
To: Alexey Dobriyan <adobriyan@gmail.com>
In-Reply-To: <20100421155547.GA4222@x200>
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Date: Wed, 21 Apr 2010 10:21:39 +1000
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Cc: Christian Kujau <lists@nerdbynature.de>,
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On Wed, 2010-04-21 at 18:55 +0300, Alexey Dobriyan wrote:
> On Tue, Apr 20, 2010 at 10:18:18PM +1000, Michael Ellerman wrote:
> > On Mon, 2010-04-19 at 23:45 -0700, Christian Kujau wrote:
> > --- a/fs/proc/proc_devtree.c
> > +++ b/fs/proc/proc_devtree.c
> > @@ -175,6 +175,24 @@ retry:
> >         return fixed_name;
> >  }
> > =20
> > +static const char *unslash_name(const char *name)
> > +{
> > +       char *p, *fixed_name;
> > +
> > +       fixed_name =3D kstrdup(name);
> > +       if (!fixed_name) {
> > +               printk(KERN_ERR "device-tree: Out of memory trying to u=
nslash "
> > +                               "name \"%s\"\n", name);
> > +               return name;
> > +       }
> > +
> > +       p =3D fixed_name;
> > +       while ((p =3D strstr(p, "/")))
> > +               *p++ =3D '_';
>=20
> This is wasteful. :-)

Whatever, patches welcome :)

> Also, I hope we won't spit message every time allocation fail.

We do. Your system is mostly hosed anyway, but feel free to rate limit
it or something.

The error handling in there is a bit dubious, if the alloc fails we just
return the old name, which we know is bogus. It should probably return
NULL and the calling code can check - same for fixup_name().

cheers

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