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Subject[PATCH v4] of: dynamic: fix memory leak related to properties of __of_node_dup
Date
If a node with no properties is dynamically added, then a property is
dynamically added to the node, then the property is dynamically removed,
the result will be node->properties == NULL and node->deadprops != NULL.

Add a separate function to release the properties in both lists.

Signed-off-by: Lixin Wang <alan.1.wang@nokia-sbell.com>
Reviewed-by: Frank Rowand <frank.rowand@sony.com>
---
Thanks the idea from Rob Herring, that I forgot to mention at patch v3.
Thanks Frank Rowand for writing to me the example.

v3 -> v4:
* Using the style that is more consistent with device tree
code, as suggested by Frank Rowand

drivers/of/dynamic.c | 25 +++++++++++++------------
1 file changed, 13 insertions(+), 12 deletions(-)

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index 301b6db..f33b7c2 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -315,6 +315,17 @@ int of_detach_node(struct device_node *np)
}
EXPORT_SYMBOL_GPL(of_detach_node);

+static void property_list_free(struct property *prop_list)
+{
+ struct property *prop;
+
+ for (prop = prop_list; prop != NULL; prop = prop->next) {
+ kfree(prop->name);
+ kfree(prop->value);
+ kfree(prop);
+ }
+}
+
/**
* of_node_release() - release a dynamically allocated node
* @kref: kref element of the node to be released
@@ -324,7 +335,6 @@ EXPORT_SYMBOL_GPL(of_detach_node);
void of_node_release(struct kobject *kobj)
{
struct device_node *node = kobj_to_device_node(kobj);
- struct property *prop = node->properties;

/* We should never be releasing nodes that haven't been detached. */
if (!of_node_check_flag(node, OF_DETACHED)) {
@@ -335,18 +345,9 @@ void of_node_release(struct kobject *kobj)
if (!of_node_check_flag(node, OF_DYNAMIC))
return;

- while (prop) {
- struct property *next = prop->next;
- kfree(prop->name);
- kfree(prop->value);
- kfree(prop);
- prop = next;
+ property_list_free(node->properties);
+ property_list_free(node->deadprops);

- if (!prop) {
- prop = node->deadprops;
- node->deadprops = NULL;
- }
- }
kfree(node->full_name);
kfree(node->data);
kfree(node);
--
2.6.2
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