linux-kernel - [PATCH v3] of: dynamic: fix memory leak related to properties of __of_node

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 19 Oct 2017 17:40:06 +0800
From:   Lixin Wang <alan.1.wang@...ia-sbell.com>
To:     Rob Herring <robh+dt@...nel.org>,
        Frank Rowand <frowand.list@...il.com>
CC:     <linux-kernel@...r.kernel.org>, <devicetree@...r.kernel.org>,
        Lixin Wang <alan.1.wang@...ia-sbell.com>
Subject: [PATCH v3] of: dynamic: fix memory leak related to properties of __of_node_dup

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@...ia-sbell.com>
---
v2 -> v3:
 * Add a separate function to release the properties in both lists.
 * Change the patch description for this change.

 drivers/of/dynamic.c | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/drivers/of/dynamic.c b/drivers/of/dynamic.c
index 301b6db..b28511f 100644
--- a/drivers/of/dynamic.c
+++ b/drivers/of/dynamic.c
@@ -315,6 +315,19 @@ int of_detach_node(struct device_node *np)
 }
 EXPORT_SYMBOL_GPL(of_detach_node);
 
+static void __of_property_list_release(struct property *prop)
+{
+	struct property *next;
+
+	while (prop) {
+		next = prop->next;
+		kfree(prop->name);
+		kfree(prop->value);
+		kfree(prop);
+		prop = next;
+	}
+}
+
 /**
  * of_node_release() - release a dynamically allocated node
  * @kref: kref element of the node to be released
@@ -324,7 +337,6 @@ 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 +347,9 @@ 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;
+	__of_property_list_release(node->properties);
+	__of_property_list_release(node->deadprops);
 
-		if (!prop) {
-			prop = node->deadprops;
-			node->deadprops = NULL;
-		}
-	}
 	kfree(node->full_name);
 	kfree(node->data);
 	kfree(node);
-- 
2.6.2