Re: [PATCH] Coccinelle : Script to detect cast after memory allocation

From: Julia Lawall
Date: Sat Jun 14 2014 - 15:37:39 EST


On Sun, 15 Jun 2014, Himangi Saraogi wrote:

> Hi,
>
> I have run the generic rule but it does not detect the cases of
> cast where the k[mzc]alloc or the kmem functions are used. I have used
> flags like recursive-includes, as suggested by Julia, but not any of the
> cases covered by the original script are detected.

Are other things detected? You could always expand the rule to be more
comprehensive.

julia


> Thanks
> Himangi
>
>
> On 14 June 2014 22:31, Joe Perches <joe@xxxxxxxxxxx> wrote:
> On Sat, 2014-06-14 at 18:11 +0200, Julia Lawall wrote:
> > On Sat, 14 Jun 2014, Joe Perches wrote:
> []
> > > Perhaps make this more generic for any void *?
> > >
> > > Something like:
> > >
> > > @@
> > > void *t;
> > > type other;
> > > @@
> > >
> > > - Â Â Â (other *)t
> > > + Â Â Â t
> []
> > Perhaps it would be reasonable to add this among the specific
> functions.
> > That is, t could be part of the disjunctions.
>
> You do have to make sure that the
> "casted to" type is not dereferenced.
>
> ie: don't transform
>
> void func(void *foo)
> {
> Â Â Â Â unsigned long bar = *(unsigned long *)foo;
> }
>
> Also there may be some __user cast types and
> such that may be necessary to exclude too.
>
>
>
>
>
>