Re: [PATCH] drm/amdgpu: Annotate struct amdgpu_bo_list with __counted_by

[Alex Deucher]

Applied.  Thanks!

Alex

On Thu, Oct 5, 2023 at 10:32 AM Christian König
<ckoenig.leichtzumerken@xxxxxxxxx> wrote:
>
> Am 04.10.23 um 01:29 schrieb Kees Cook:
> > Prepare for the coming implementation by GCC and Clang of the __counted_by
> > attribute. Flexible array members annotated with __counted_by can have
> > their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
> > array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> > functions).
> >
> > As found with Coccinelle[1], add __counted_by for struct amdgpu_bo_list.
> > Additionally, since the element count member must be set before accessing
> > the annotated flexible array member, move its initialization earlier.
> >
> > Cc: Alex Deucher <alexander.deucher@xxxxxxx>
> > Cc: "Christian König" <christian.koenig@xxxxxxx>
> > Cc: "Pan, Xinhui" <Xinhui.Pan@xxxxxxx>
> > Cc: David Airlie <airlied@xxxxxxxxx>
> > Cc: Daniel Vetter <daniel@xxxxxxxx>
> > Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx>
> > Cc: Luben Tuikov <luben.tuikov@xxxxxxx>
> > Cc: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> > Cc: Felix Kuehling <Felix.Kuehling@xxxxxxx>
> > Cc: amd-gfx@xxxxxxxxxxxxxxxxxxxxx
> > Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> > Cc: linux-hardening@xxxxxxxxxxxxxxx
> > Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> > Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
>
> Reviewed-by: Christian König <christian.koenig@xxxxxxx>
>
> > ---
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c | 2 +-
> >   drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h | 2 +-
> >   2 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
> > index 6f5b641b631e..781e5c5ce04d 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.c
> > @@ -84,6 +84,7 @@ int amdgpu_bo_list_create(struct amdgpu_device *adev, struct drm_file *filp,
> >
> >       kref_init(&list->refcount);
> >
> > +     list->num_entries = num_entries;
> >       array = list->entries;
> >
> >       for (i = 0; i < num_entries; ++i) {
> > @@ -129,7 +130,6 @@ int amdgpu_bo_list_create(struct amdgpu_device *adev, struct drm_file *filp,
> >       }
> >
> >       list->first_userptr = first_userptr;
> > -     list->num_entries = num_entries;
> >       sort(array, last_entry, sizeof(struct amdgpu_bo_list_entry),
> >            amdgpu_bo_list_entry_cmp, NULL);
> >
> > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h
> > index 6a703be45d04..555cd6d877c3 100644
> > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h
> > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_bo_list.h
> > @@ -56,7 +56,7 @@ struct amdgpu_bo_list {
> >        */
> >       struct mutex bo_list_mutex;
> >
> > -     struct amdgpu_bo_list_entry entries[];
> > +     struct amdgpu_bo_list_entry entries[] __counted_by(num_entries);
> >   };
> >
> >   int amdgpu_bo_list_get(struct amdgpu_fpriv *fpriv, int id,
>