Quoting Lionel Landwerlin (2018-05-22 13:13:03)
> On 22/05/18 13:10, Chris Wilson wrote:
> > nospec quite reasonably asserts that it will never be used with an index
> > larger than unsigned long (that being the largest possibly index into an
> > C array). However, our ubi uses the convention of u64 for any large
> > integer, running afoul of the assertion on 32b. Reduce our index to an
> > unsigned long, checking for type overflow first.
> >
> > drivers/gpu/drm/i915/i915_query.c: In function 'i915_query_ioctl':
> > include/linux/compiler.h:339:38: error: call to '__compiletime_assert_119' declared with attribute error: BUILD_BUG_ON failed: sizeof(_s) > sizeof(long)
> >
> > Reported-by: kbuild-all@xxxxxx
> > Fixes: 84b510e22da7 ("drm/i915/query: Protect tainted function pointer lookup")
> > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
> > Cc: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx>
> > Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
> > Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx>
> > ---
> > drivers/gpu/drm/i915/i915_query.c | 5 ++++-
> > 1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/i915/i915_query.c b/drivers/gpu/drm/i915/i915_query.c
> > index 95f9d179afc4..3f502eef2431 100644
> > --- a/drivers/gpu/drm/i915/i915_query.c
> > +++ b/drivers/gpu/drm/i915/i915_query.c
> > @@ -102,7 +102,7 @@ int i915_query_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
> >
> > for (i = 0; i < args->num_items; i++, user_item_ptr++) {
> > struct drm_i915_query_item item;
> > - u64 func_idx;
> > + unsigned long func_idx;
> > int ret;
> >
> > if (copy_from_user(&item, user_item_ptr, sizeof(item)))
> > @@ -111,6 +111,9 @@ int i915_query_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
> I guess you can get rid of this if (item.query_id == 0) then :
Hmm, we could indeed. The choice is whether we want to make it clear
that id=0 is illegal (making it easier to add debug later?)
-Chris
_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
