[PATCH v3 1/7] drm/sysfb: simpledrm: Improve framebuffer-size validation

[Thomas Zimmermann <tzimmermann@suse.de>]

Validate the framebuffer size from the firmware against the
limitations of struct drm_display_mode. The type only stores sizes
in 16-bit fields. Fail probing on errors.

v2:
- remove unused function simplefb_get_validated_int0() (Sashiko)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Fixes: 11e8f5fd223b ("drm: Add simpledrm driver")
Cc: <stable@vger.kernel.org> # v5.14+
---
 drivers/gpu/drm/sysfb/simpledrm.c | 15 ++++-----------
 1 file changed, 4 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/sysfb/simpledrm.c b/drivers/gpu/drm/sysfb/simpledrm.c
index fc168920f2c6..15dcafa9d524 100644
--- a/drivers/gpu/drm/sysfb/simpledrm.c
+++ b/drivers/gpu/drm/sysfb/simpledrm.c
@@ -48,13 +48,6 @@ simplefb_get_validated_int(struct drm_device *dev, const char *name,
 	return drm_sysfb_get_validated_int(dev, name, value, INT_MAX);
 }
 
-static int
-simplefb_get_validated_int0(struct drm_device *dev, const char *name,
-			    uint32_t value)
-{
-	return drm_sysfb_get_validated_int0(dev, name, value, INT_MAX);
-}
-
 static const struct drm_format_info *
 simplefb_get_validated_format(struct drm_device *dev, const char *format_name)
 {
@@ -88,14 +81,14 @@ static int
 simplefb_get_width_pd(struct drm_device *dev,
 		      const struct simplefb_platform_data *pd)
 {
-	return simplefb_get_validated_int0(dev, "width", pd->width);
+	return drm_sysfb_get_validated_int0(dev, "width", pd->width, U16_MAX);
 }
 
 static int
 simplefb_get_height_pd(struct drm_device *dev,
 		       const struct simplefb_platform_data *pd)
 {
-	return simplefb_get_validated_int0(dev, "height", pd->height);
+	return drm_sysfb_get_validated_int0(dev, "height", pd->height, U16_MAX);
 }
 
 static int
@@ -144,7 +137,7 @@ simplefb_get_width_of(struct drm_device *dev, struct device_node *of_node)
 
 	if (ret)
 		return ret;
-	return simplefb_get_validated_int0(dev, "width", width);
+	return drm_sysfb_get_validated_int0(dev, "width", width, U16_MAX);
 }
 
 static int
@@ -155,7 +148,7 @@ simplefb_get_height_of(struct drm_device *dev, struct device_node *of_node)
 
 	if (ret)
 		return ret;
-	return simplefb_get_validated_int0(dev, "height", height);
+	return drm_sysfb_get_validated_int0(dev, "height", height, U16_MAX);
 }
 
 static int
-- 
2.54.0