Re: [PATCH] drm/imagination: vm: Fix heap lookup condition

[Donald Robson <Donald.Robson@imgtec.com>]

Thanks Alex!

Reviewed-by: Donald Robson <donald.robson@imgtec.com>

On Fri, 2023-12-08 at 18:08 +0100, Alex Bee wrote:
> *** CAUTION: This email originates from a source not known to Imagination Technologies. Think before you click a link or open an attachment ***
> 
> When conditionally checking for heap existence of a certian address in
> pvr_vm_bind_op_map_init the condition whether the map request comes from a
> user is incorrect: The context must not be the kernel-context to be a
> user(space) context and should be looked up in pvr_heaps.
> 
> That makes addresses coming from userspace not being verfied against the
> defined ranges and prevents firmware loading for meta cores.
> 
> Fixes: ff5f643de0bf ("drm/imagination: Add GEM and VM related code")
> Signed-off-by: Alex Bee <knaerzche@gmail.com>
> ---
>  drivers/gpu/drm/imagination/pvr_vm.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/imagination/pvr_vm.c b/drivers/gpu/drm/imagination/pvr_vm.c
> index f42345fbe4bf..82690cee978c 100644
> --- a/drivers/gpu/drm/imagination/pvr_vm.c
> +++ b/drivers/gpu/drm/imagination/pvr_vm.c
> @@ -225,7 +225,7 @@ pvr_vm_bind_op_map_init(struct pvr_vm_bind_op *bind_op,
>  			u64 device_addr, u64 size)
>  {
>  	struct drm_gem_object *obj = gem_from_pvr_gem(pvr_obj);
> -	const bool is_user = vm_ctx == vm_ctx->pvr_dev->kernel_vm_ctx;
> +	const bool is_user = vm_ctx != vm_ctx->pvr_dev->kernel_vm_ctx;
>  	const u64 pvr_obj_size = pvr_gem_object_size(pvr_obj);
>  	struct sg_table *sgt;
>  	u64 offset_plus_size;