Re: [2.6 patch] drivers/ieee1394/raw1394.c: fix a NULL pointer dereference

[Adrian Bunk <bunk@stusta.de>]

On Mon, Nov 21, 2005 at 12:45:14AM +0100, Jesper Juhl wrote:
> On 11/21/05, Adrian Bunk <bunk@stusta.de> wrote:
> > The coverity checker spotted that this was a NULL pointer dereference in
> > the "if (copy_from_user(...))" case.
> >
> >
> > Signed-off-by: Adrian Bunk <bunk@stusta.de>
> >
> > --- linux-2.6.15-rc1-mm2-full/drivers/ieee1394/raw1394.c.old    2005-11-20 22:08:57.000000000 +0100
> > +++ linux-2.6.15-rc1-mm2-full/drivers/ieee1394/raw1394.c        2005-11-20 22:09:34.000000000 +0100
> > @@ -2166,7 +2166,8 @@
> >                         }
> >                 }
> >         }
> > -       kfree(cache->filled_head);
> > +       if(cache->filled_head)
> > +               kfree(cache->filled_head);
> >         kfree(cache);
> >
> Hmmm,  kfree() deals with NULL pointers just fine, so there's no
> problem if cache->filled_head is NULL. There is, however, a NULL
> pointer deref problem if `cache' is NULL, but that's not what your
> patch checks for.
>...

OK, I was blind...

I've just sent a better patch.

cu
Adrian

-- 

       "Is there not promise of rain?" Ling Tan asked suddenly out
        of the darkness. There had been need of rain for many days.
       "Only a promise," Lao Er said.
                                       Pearl S. Buck - Dragon Seed

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