Re: [PATCH v2 2/4] coccinelle: api: extend memdup_user rule with vmemdup_user()

From: Julia Lawall
Date: Mon Jun 08 2020 - 14:36:36 EST




On Mon, 8 Jun 2020, Markus Elfring wrote:

> â
> +++ b/scripts/coccinelle/api/memdup_user.cocci
> @@ -39,6 +39,28 @@ â
> â
> > +@depends on patch@
> > +expression from,to,size;
> > +identifier l1,l2;
> > +@@
> > +
> > +- to = \(kvmalloc\|kvzalloc\)(size,\(GFP_KERNEL\|GFP_USER\));
> > ++ to = vmemdup_user(from,size);
>
> I suggest to combine the desired adjustment with the previous SmPL rule
> by using another disjunction.
>
>
> > +@rv depends on !patch@
> > +expression from,to,size;
> > +position p;
> > +statement S1,S2;
> > +@@
> > +
> > +* to = \(kvmalloc@p\|kvzalloc@p\)(size,\(GFP_KERNEL\|GFP_USER\));
> > + if (to==NULL || ...) S1
> > + if (copy_from_user(to, from, size) != 0)
> > + S2
>
> How does the SmPL asterisk functionality fit to the operation
> modes âorgâ and âreportâ?

Make coccicheck uses --no-show-diff for org and report modes, so the * has
no effect in those cases.

julia