Messages in this thread | | | Date | Wed, 10 Dec 2014 15:55:02 +0100 | Subject | Re: [drm-intel:topic/core-stuff 32/37] drivers/gpu/drm/drm_crtc.c:4472 drm_mode_crtc_set_gamma_size() warn: double check that we're allocating correct size: 2 vs 6 | From | Daniel Vetter <> |
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Forgotten to add mailing lists. -Daniel
On Wed, Dec 10, 2014 at 3:53 PM, Daniel Vetter <daniel.vetter@ffwll.ch> wrote: > On Wed, Dec 10, 2014 at 3:03 PM, Dan Carpenter <dan.carpenter@oracle.com> wrote: >> From a style prespective this should be: >> >> crtc->gamma_store = kcalloc(gamma_size * 3, sizeof(uint16_t), >> GFP_KERNEL); >> >> Because the elements are sizeof(uint16_t), we are allocating 3 >> arrays of gamma_size elements. But I guess it's nice to move all the >> constants to one side of the equation so that it tests for integer >> overflows... Whatever you decided is fine, this is a one time email >> that is auto-genenerated. > > Imo the point of kcalloc and kmalloc_array is to get the overflow > checks correct. Putting the *3 to the gamma_size (which can be fairly > big and migth come from dubios places) means we still have to deal > with overflow headaches. sizeof(uint16_t)*3 is trivial to see that > it's not overflowing. > > I think your style guide here is exactly _not_ what we should do as > best practice for safe code. > -Daniel > -- > Daniel Vetter > Software Engineer, Intel Corporation > +41 (0) 79 365 57 48 - http://blog.ffwll.ch
-- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch
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