Re: integer overflows in kernel/relay.c

[Andrew Morton <akpm@linux-foundation.org>]

On Thu, 09 Feb 2012 13:41:38 +0100 Jens Axboe <axboe@kernel.dk> wrote:

> On 02/08/2012 11:25 PM, Andrew Morton wrote:
> > On Wed, 08 Feb 2012 09:34:16 +0100
> > Jens Axboe <axboe@kernel.dk> wrote:
> > 
> >> On 02/07/2012 03:11 PM, Dan Carpenter wrote:
> >>> My static checker is warning about integer overflows in kernel/relay.c
> >>>
> >>> relay_create_buf()
> >>>    170  
> >>>    171          buf->padding = kmalloc(chan->n_subbufs * sizeof(size_t *), GFP_KERNEL);
> >>>                                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> >>> This can only overflow on 32bit systems.
> >>
> >> Correct
> > 
> > This is a relatively common problem.  Converting a kzalloc() call to
> > kcalloc() fixes it.  But we do not have a non-zeroing version of
> > kcalloc().
> > 
> > Please, someone complete this patch and send it to me!
> > 
> > 
> > --- a/include/linux/slab.h~a
> > +++ a/include/linux/slab.h
> > @@ -240,11 +240,16 @@ size_t ksize(const void *);
> >   * for general use, and so are not documented here. For a full list of
> >   * potential flags, always refer to linux/gfp.h.
> >   */
> > -static inline void *kcalloc(size_t n, size_t size, gfp_t flags)
> > +static inline void *wtf_do_i_call_this(size_t n, size_t size, gfp_t flags)
> 
> kzcalloc()? Either that, or long_and_verbose().

I would need to be k_not_z_calloc() because it's the non-zeroing version.

kcallocn()?  knalloc()?  kncalloc()?