[PATCH] pinctrl: core: fix possible memory leak in error path in pinctrl_enable()

[Yang Yingliang <yangyingliang@xxxxxxxxxx>]

In devm_pinctrl_register(), if pinctrl_enable() fails in pinctrl_register(),
the "pctldev" has not been added to dev resources, so devm_pinctrl_dev_release()
can not be called, it leads memory leak.

And some driver calls pinctrl_register_and_init() which is not devm_ managed,
it also leads memory leak if pinctrl_enable() fails.

To fix this, add a flag devm_allocated to struct pinctrl_dev, free the memory
by checking this flag.

Fixes: 5038a66dad01 ("pinctrl: core: delete incorrect free in pinctrl_enable()")
Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
---
 drivers/pinctrl/core.c | 9 +++++++++
 drivers/pinctrl/core.h | 1 +
 2 files changed, 10 insertions(+)

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index cffeb869130d..374c36f5c759 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -2125,6 +2125,13 @@ int pinctrl_enable(struct pinctrl_dev *pctldev)
 	error = pinctrl_claim_hogs(pctldev);
 	if (error) {
 		dev_err(pctldev->dev, "could not claim hogs: %i\n", error);
+		if (!pctldev->devm_allocated) {
+			pinctrl_free_pindescs(pctldev, pctldev->desc->pins,
+					      pctldev->desc->npins);
+			mutex_destroy(&pctldev->mutex);
+			kfree(pctldev);
+		}
+
 		return error;
 	}
 
@@ -2283,6 +2290,7 @@ struct pinctrl_dev *devm_pinctrl_register(struct device *dev,
 		return pctldev;
 	}
 
+	pctldev->devm_allocated = true;
 	*ptr = pctldev;
 	devres_add(dev, ptr);
 
@@ -2319,6 +2327,7 @@ int devm_pinctrl_register_and_init(struct device *dev,
 		return error;
 	}
 
+	(*pctldev)->devm_allocated = true;
 	*ptr = *pctldev;
 	devres_add(dev, ptr);
 
diff --git a/drivers/pinctrl/core.h b/drivers/pinctrl/core.h
index 837fd5bd903d..bf57ce4fe927 100644
--- a/drivers/pinctrl/core.h
+++ b/drivers/pinctrl/core.h
@@ -72,6 +72,7 @@ struct pinctrl_dev {
 #ifdef CONFIG_DEBUG_FS
 	struct dentry *device_root;
 #endif
+	bool devm_allocated;
 };
 
 /**
-- 
2.25.1