[PATCH] regulator: rn5t618: Fix Fix out of bounds array access

[Axel Lin]

The commit "regulator: rn5t618: Add RN5T567 PMIC support" added
RN5T618_DCDC4 to the enum, then RN5T618_REG_NUM is also changed.
So for rn5t618, there is out of bounds array access when checking
regulators[i].name in the for loop.

The number of regulators is different for rn5t567 and rn5t618, so we had
better remove RN5T618_REG_NUM and get the correct num_regulators during
probe instead.

Fixes: ed6d362d8dbc ("regulator: rn5t618: Add RN5T567 PMIC support")
Signed-off-by: Axel Lin <axel.lin@xxxxxxxxxx>
---
 drivers/regulator/rn5t618-regulator.c | 8 ++++----
 include/linux/mfd/rn5t618.h           | 1 -
 2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/regulator/rn5t618-regulator.c b/drivers/regulator/rn5t618-regulator.c
index 8d2819e..0c09143 100644
--- a/drivers/regulator/rn5t618-regulator.c
+++ b/drivers/regulator/rn5t618-regulator.c
@@ -85,14 +85,17 @@ static int rn5t618_regulator_probe(struct platform_device *pdev)
 	struct regulator_config config = { };
 	struct regulator_dev *rdev;
 	struct regulator_desc *regulators;
+	int num_regulators;
 	int i;
 
 	switch (rn5t618->variant) {
 	case RN5T567:
 		regulators = rn5t567_regulators;
+		num_regulators = ARRAY_SIZE(rn5t567_regulators);
 		break;
 	case RN5T618:
 		regulators = rn5t618_regulators;
+		num_regulators = ARRAY_SIZE(rn5t618_regulators);
 		break;
 	default:
 		return -EINVAL;
@@ -101,10 +104,7 @@ static int rn5t618_regulator_probe(struct platform_device *pdev)
 	config.dev = pdev->dev.parent;
 	config.regmap = rn5t618->regmap;
 
-	for (i = 0; i < RN5T618_REG_NUM; i++) {
-		if (!regulators[i].name)
-			continue;
-
+	for (i = 0; i < num_regulators; i++) {
 		rdev = devm_regulator_register(&pdev->dev,
 					       &regulators[i],
 					       &config);
diff --git a/include/linux/mfd/rn5t618.h b/include/linux/mfd/rn5t618.h
index e5a6cde..d7b3155 100644
--- a/include/linux/mfd/rn5t618.h
+++ b/include/linux/mfd/rn5t618.h
@@ -233,7 +233,6 @@ enum {
 	RN5T618_LDO5,
 	RN5T618_LDORTC1,
 	RN5T618_LDORTC2,
-	RN5T618_REG_NUM,
 };
 
 enum {
-- 
2.9.3