| Message ID | 20201129200927.1854104-1-arnd@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | drm/kmb: fix array bounds warning | expand |
Hi Arnd, Thanks for your patch. > -----Original Message----- > From: Arnd Bergmann <arnd@kernel.org> > Sent: Sunday, November 29, 2020 12:09 PM > To: Chrisanthus, Anitha <anitha.chrisanthus@intel.com>; Dea, Edmund J > <edmund.j.dea@intel.com>; David Airlie <airlied@linux.ie>; Daniel Vetter > <daniel@ffwll.ch>; Sam Ravnborg <sam@ravnborg.org> > Cc: Arnd Bergmann <arnd@arndb.de>; lkp <lkp@intel.com>; dri- > devel@lists.freedesktop.org; linux-kernel@vger.kernel.org > Subject: [PATCH] drm/kmb: fix array bounds warning > > From: Arnd Bergmann <arnd@arndb.de> > > gcc warns about an out-of-bounds access when the using nonzero > values for 'plane_id' on kmb->plane_status: > > drivers/gpu/drm/kmb/kmb_plane.c: In function 'kmb_plane_atomic_disable': > drivers/gpu/drm/kmb/kmb_plane.c:128:20: warning: array subscript 3 is > above array bounds of 'struct layer_status[1]' [-Warray-bounds] > 128 | kmb->plane_status[plane_id].ctrl = LCD_CTRL_GL2_ENABLE; > | ~~~~~~~~~~~~~~~~~^~~~~~~~~~ > drivers/gpu/drm/kmb/kmb_plane.c:125:20: warning: array subscript 2 is > above array bounds of 'struct layer_status[1]' [-Warray-bounds] > 125 | kmb->plane_status[plane_id].ctrl = LCD_CTRL_GL1_ENABLE; > | ~~~~~~~~~~~~~~~~~^~~~~~~~~~ > drivers/gpu/drm/kmb/kmb_plane.c:122:20: warning: array subscript 1 is > above array bounds of 'struct layer_status[1]' [-Warray-bounds] > 122 | kmb->plane_status[plane_id].ctrl = LCD_CTRL_VL2_ENABLE; > > Having the array truncated to one entry seems intentional, so add > a range check before indexing it to make it clearer what is going > on and shut up the warning. > > I received the warning from the kernel test robot after a private > patch that turns on Warray-bounds unconditionally. > > Fixes: 7f7b96a8a0a1 ("drm/kmb: Add support for KeemBay Display") > Reported-by: kernel test robot <lkp@intel.com> > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > drivers/gpu/drm/kmb/kmb_plane.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/gpu/drm/kmb/kmb_plane.c > b/drivers/gpu/drm/kmb/kmb_plane.c > index 8448d1edb553..be8eea3830c1 100644 > --- a/drivers/gpu/drm/kmb/kmb_plane.c > +++ b/drivers/gpu/drm/kmb/kmb_plane.c > @@ -114,6 +114,9 @@ static void kmb_plane_atomic_disable(struct > drm_plane *plane, > > kmb = to_kmb(plane->dev); > > + if (WARN_ON(plane_id >= KMB_MAX_PLANES)) > + return; > + Looks good. Reviewed-by: Anitha Chrisanthus <anitha.chrisanthus@intel.com> > switch (plane_id) { > case LAYER_0: > kmb->plane_status[plane_id].ctrl = LCD_CTRL_VL1_ENABLE; > -- > 2.27.0 _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
Hi Anitha, On Mon, Nov 30, 2020 at 10:19:13PM +0000, Chrisanthus, Anitha wrote: > Hi Arnd, > Thanks for your patch. > > > -----Original Message----- > > From: Arnd Bergmann <arnd@kernel.org> > > Sent: Sunday, November 29, 2020 12:09 PM > > To: Chrisanthus, Anitha <anitha.chrisanthus@intel.com>; Dea, Edmund J > > <edmund.j.dea@intel.com>; David Airlie <airlied@linux.ie>; Daniel Vetter > > <daniel@ffwll.ch>; Sam Ravnborg <sam@ravnborg.org> > > Cc: Arnd Bergmann <arnd@arndb.de>; lkp <lkp@intel.com>; dri- > > devel@lists.freedesktop.org; linux-kernel@vger.kernel.org > > Subject: [PATCH] drm/kmb: fix array bounds warning > > > > From: Arnd Bergmann <arnd@arndb.de> > > > > gcc warns about an out-of-bounds access when the using nonzero > > values for 'plane_id' on kmb->plane_status: ... > Looks good. > > Reviewed-by: Anitha Chrisanthus <anitha.chrisanthus@intel.com> You wanted a little time to get comforable with dim, so I picked up this patch and pushed it to drm-misc-next. Sam _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
diff --git a/drivers/gpu/drm/kmb/kmb_plane.c b/drivers/gpu/drm/kmb/kmb_plane.c index 8448d1edb553..be8eea3830c1 100644 --- a/drivers/gpu/drm/kmb/kmb_plane.c +++ b/drivers/gpu/drm/kmb/kmb_plane.c @@ -114,6 +114,9 @@ static void kmb_plane_atomic_disable(struct drm_plane *plane, kmb = to_kmb(plane->dev); + if (WARN_ON(plane_id >= KMB_MAX_PLANES)) + return; + switch (plane_id) { case LAYER_0: kmb->plane_status[plane_id].ctrl = LCD_CTRL_VL1_ENABLE;