[PATCH] drm/vc4: hdmi: Fix off by ones in vc4_hdmi_read/write()

[Dan Carpenter]

The variant->registers[] has ->num_registers elements so the >
comparison needs to be changes to >= to prevent an out of bounds
access.

Fixes: 311e305fdb4e ("drm/vc4: hdmi: Implement a register layout abstraction")
Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>
---
 drivers/gpu/drm/vc4/vc4_hdmi_regs.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi_regs.h b/drivers/gpu/drm/vc4/vc4_hdmi_regs.h
index a5f1354e3e06..47364bd3960d 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi_regs.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi_regs.h
@@ -398,7 +398,7 @@ static inline u32 vc4_hdmi_read(struct vc4_hdmi *hdmi,
 	const struct vc4_hdmi_variant *variant = hdmi->variant;
 	void __iomem *base;
 
-	if (reg > variant->num_registers) {
+	if (reg >= variant->num_registers) {
 		dev_warn(&hdmi->pdev->dev,
 			 "Invalid register ID %u\n", reg);
 		return 0;
@@ -424,7 +424,7 @@ static inline void vc4_hdmi_write(struct vc4_hdmi *hdmi,
 	const struct vc4_hdmi_variant *variant = hdmi->variant;
 	void __iomem *base;
 
-	if (reg > variant->num_registers) {
+	if (reg >= variant->num_registers) {
 		dev_warn(&hdmi->pdev->dev,
 			 "Invalid register ID %u\n", reg);
 		return;
-- 
2.28.0