Re: [PATCH] remoteproc: core: Remove casting to rproc_handle_resource_t

[Mathieu Poirier]

On Mon, 22 Feb 2021 at 15:48, Sami Tolvanen <samitolvanen@xxxxxxxxxx> wrote:
>
> Hi,
>
> On Sun, Feb 21, 2021 at 11:18 PM Jindong Yue <jindong.yue@xxxxxxx> wrote:
> >
> > There are four different callback functions that are used for the
> > rproc_handle_resource_t callback that all have different second
> > parameter types.
> >
> > rproc_handle_vdev -> struct fw_rsc_vdev
> > rproc_handle_trace -> struct fw_rsc_trace
> > rproc_handle_devmem -> struct fw_rsc_devmem
> > rproc_handle_carveout -> struct fw_rsc_carveout
> >
> > These callbacks are cast to rproc_handle_resource_t so that there is no
> > error about incompatible pointer types. Unfortunately, this is a control
> > flow integrity violation, which verifies that the callback function's
> > types match the prototypes exactly before jumping.
>
> Thank you for sending the patch! It might be worth noting that Clang's
> Control-Flow Integrity checking is currently used only in Android
> kernels, so while the type mismatches are real and should be fixed,
> they don't result in runtime errors without this feature.
>
> > To fix this, change the second parameter of all functions to void * and
> > use a local variable with the correct type so that everything works
> > properly. With this, we can remove casting to rproc_handle_resource_t
> > for these functions.
> >
> > Signed-off-by: Jindong Yue <jindong.yue@xxxxxxx>
> > Reviewed-by: Peng Fan <peng.fan@xxxxxxx>
>
> This looks correct to me. Please feel free to add:
>
> Reviewed-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>

Where is the original patch?  I can't find it on the linux-remoteproc
and linux-kernel mailing lists.

>
> Sami