Re: [PATCH RESEND v3] checkpatch: add uninitialized pointer with __free attribute check
From: ally heev
Date: Wed Nov 05 2025 - 01:27:32 EST
On Tue, 2025-11-04 at 14:28 +0100, Geert Uytterhoeven wrote:
> Hi Ally,
>
> On Tue, 4 Nov 2025 at 10:58, Ally Heev <allyheev@xxxxxxxxx> wrote:
> > uninitialized pointers with __free attribute can cause undefined
> > behaviour as the memory allocated to the pointer is freed
> > automatically when the pointer goes out of scope.
> > add check in checkpatch to detect such issues
> >
> > Suggested-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > Link: https://lore.kernel.org/all/8a4c0b43-cf63-400d-b33d-d9c447b7e0b9@suswa.mountain/
> > Acked-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> > Signed-off-by: Ally Heev <allyheev@xxxxxxxxx>
>
> Thanks for your patch!
>
> > --- a/Documentation/dev-tools/checkpatch.rst
> > +++ b/Documentation/dev-tools/checkpatch.rst
> > @@ -1009,6 +1009,11 @@ Functions and Variables
> >
> > return bar;
> >
> > + **UNINITIALIZED_PTR_WITH_FREE**
> > + Pointers with __free attribute should be initialized. Not doing so
> > + may lead to undefined behavior as the memory allocated (garbage,
> > + in case not initialized) to the pointer is freed automatically
> > + when the pointer goes out of scope.
>
> I think this is misleading, and can be improved: if the pointer is
> uninitialized, no memory was allocated?
yeah right. Will update in next version
Regards,
Ally