Re: [PATCH v5 4/4] clk: basic clock hardware types

[Sascha Hauer <s.hauer@pengutronix.de>]

On Sat, Mar 03, 2012 at 12:29:01AM -0800, Mike Turquette wrote:
> +struct clk *clk_register_divider(struct device *dev, const char *name,
> +		const char *parent_name, unsigned long flags,
> +		void __iomem *reg, u8 shift, u8 width,
> +		u8 clk_divider_flags, spinlock_t *lock)
> +{
> +	struct clk_divider *div;
> +	char **parent_names = NULL;
> +	u8 len;
> +
> +	div = kmalloc(sizeof(struct clk_divider), GFP_KERNEL);
> +
> +	if (!div) {
> +		pr_err("%s: could not allocate divider clk\n", __func__);
> +		return ERR_PTR(-ENOMEM);
> +	}
> +
> +	/* struct clk_divider assignments */
> +	div->reg = reg;
> +	div->shift = shift;
> +	div->width = width;
> +	div->flags = clk_divider_flags;
> +	div->lock = lock;
> +
> +	if (parent_name) {
> +		parent_names = kmalloc(sizeof(char *), GFP_KERNEL);
> +
> +		if (! parent_names)
> +			goto out;
> +
> +		len = sizeof(char) * strlen(parent_name);
> +
> +		parent_names[0] = kmalloc(len, GFP_KERNEL);
> +
> +		if (!parent_names[0])
> +			goto out;
> +
> +		strncpy(parent_names[0], parent_name, len);
> +	}
> +
> +out:
> +	return clk_register(dev, name,
> +			&clk_divider_ops, &div->hw,
> +			parent_names,
> +			(parent_name ? 1 : 0),
> +			flags);
> +}

clk_register_divider and also clk_register_gate have some problems.
First you allocate memory with exactly the string length without
the terminating 0. Then the functions leak memory when clk_register
fails. Could you fold in the following patch to fix this?

Sascha

8<--------------------------------------------------

fix divider/gate registration

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 drivers/clk/clk-divider.c    |   34 +++++++++++++++-------------------
 drivers/clk/clk-gate.c       |   33 ++++++++++++++-------------------
 include/linux/clk-provider.h |    2 ++
 3 files changed, 31 insertions(+), 38 deletions(-)

diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
index 8f02930..99b6b55 100644
--- a/drivers/clk/clk-divider.c
+++ b/drivers/clk/clk-divider.c
@@ -156,14 +156,13 @@ struct clk *clk_register_divider(struct device *dev, const char *name,
 		u8 clk_divider_flags, spinlock_t *lock)
 {
 	struct clk_divider *div;
-	char **parent_names = NULL;
-	u8 len;
+	struct clk *clk;
 
-	div = kmalloc(sizeof(struct clk_divider), GFP_KERNEL);
+	div = kzalloc(sizeof(struct clk_divider), GFP_KERNEL);
 
 	if (!div) {
 		pr_err("%s: could not allocate divider clk\n", __func__);
-		return ERR_PTR(-ENOMEM);
+		return NULL;
 	}
 
 	/* struct clk_divider assignments */
@@ -174,25 +173,22 @@ struct clk *clk_register_divider(struct device *dev, const char *name,
 	div->lock = lock;
 
 	if (parent_name) {
-		parent_names = kmalloc(sizeof(char *), GFP_KERNEL);
-
-		if (! parent_names)
-			goto out;
-
-		len = sizeof(char) * strlen(parent_name);
-
-		parent_names[0] = kmalloc(len, GFP_KERNEL);
-
-		if (!parent_names[0])
+		div->parent[0] = kstrdup(parent_name, GFP_KERNEL);
+		if (!div->parent[0])
 			goto out;
-
-		strncpy(parent_names[0], parent_name, len);
 	}
 
-out:
-	return clk_register(dev, name,
+	clk = clk_register(dev, name,
 			&clk_divider_ops, &div->hw,
-			parent_names,
+			div->parent,
 			(parent_name ? 1 : 0),
 			flags);
+	if (clk)
+		return clk;
+
+out:
+	kfree(div->parent[0]);
+	kfree(div);
+
+	return NULL;
 }
diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c
index e831f7b..92c0489 100644
--- a/drivers/clk/clk-gate.c
+++ b/drivers/clk/clk-gate.c
@@ -80,14 +80,13 @@ struct clk *clk_register_gate(struct device *dev, const char *name,
 		u8 clk_gate_flags, spinlock_t *lock)
 {
 	struct clk_gate *gate;
-	char **parent_names = NULL;
-	u8 len;
+	struct clk *clk;
 
-	gate = kmalloc(sizeof(struct clk_gate), GFP_KERNEL);
+	gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
 
 	if (!gate) {
 		pr_err("%s: could not allocate gated clk\n", __func__);
-		return ERR_PTR(-ENOMEM);
+		return NULL;
 	}
 
 	/* struct clk_gate assignments */
@@ -97,25 +96,21 @@ struct clk *clk_register_gate(struct device *dev, const char *name,
 	gate->lock = lock;
 
 	if (parent_name) {
-		parent_names = kmalloc(sizeof(char *), GFP_KERNEL);
-
-		if (! parent_names)
-			goto out;
-
-		len = sizeof(char) * strlen(parent_name);
-
-		parent_names[0] = kmalloc(len, GFP_KERNEL);
-
-		if (!parent_names[0])
+		gate->parent[0] = kstrdup(parent_name, GFP_KERNEL);
+		if (!gate->parent[0])
 			goto out;
-
-		strncpy(parent_names[0], parent_name, len);
 	}
 
-out:
-	return clk_register(dev, name,
+	clk = clk_register(dev, name,
 			&clk_gate_ops, &gate->hw,
-			parent_names,
+			gate->parent,
 			(parent_name ? 1 : 0),
 			flags);
+	if (clk)
+		return clk;
+out:
+	kfree(gate->parent[0]);
+	kfree(gate);
+
+	return NULL;
 }
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 9b7dd5e..ed1f918 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -174,6 +174,7 @@ struct clk_gate {
 	u8		bit_idx;
 	u8		flags;
 	spinlock_t	*lock;
+	char		*parent[1];
 };
 
 #define CLK_GATE_SET_TO_DISABLE		BIT(0)
@@ -210,6 +211,7 @@ struct clk_divider {
 	u8		width;
 	u8		flags;
 	spinlock_t	*lock;
+	char		*parent[1];
 };
 
 #define CLK_DIVIDER_ONE_BASED		BIT(0)
-- 
1.7.9.1

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