driver core: platform: Prevent resouce overflow from causing infinite loops
authorSimon Schwartz <kern.simon@theschwartz.xyz>
Tue, 10 Dec 2019 22:41:37 +0000 (17:41 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 28 Feb 2020 14:42:32 +0000 (15:42 +0100)
[ Upstream commit 39cc539f90d035a293240c9443af50be55ee81b8 ]

num_resources in the platform_device struct is declared as a u32.  The
for loops that iterate over num_resources use an int as the counter,
which can cause infinite loops on architectures with smaller ints.
Change the loop counters to u32.

Signed-off-by: Simon Schwartz <kern.simon@theschwartz.xyz>
Link: https://lore.kernel.org/r/2201ce63a2a171ffd2ed14e867875316efcf71db.camel@theschwartz.xyz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/base/platform.c

index f90b1b9..6cdc198 100644 (file)
@@ -28,6 +28,7 @@
 #include <linux/limits.h>
 #include <linux/property.h>
 #include <linux/kmemleak.h>
+#include <linux/types.h>
 
 #include "base.h"
 #include "power/power.h"
@@ -68,7 +69,7 @@ void __weak arch_setup_pdev_archdata(struct platform_device *pdev)
 struct resource *platform_get_resource(struct platform_device *dev,
                                       unsigned int type, unsigned int num)
 {
-       int i;
+       u32 i;
 
        for (i = 0; i < dev->num_resources; i++) {
                struct resource *r = &dev->resource[i];
@@ -153,7 +154,7 @@ struct resource *platform_get_resource_byname(struct platform_device *dev,
                                              unsigned int type,
                                              const char *name)
 {
-       int i;
+       u32 i;
 
        for (i = 0; i < dev->num_resources; i++) {
                struct resource *r = &dev->resource[i];
@@ -350,7 +351,8 @@ EXPORT_SYMBOL_GPL(platform_device_add_properties);
  */
 int platform_device_add(struct platform_device *pdev)
 {
-       int i, ret;
+       u32 i;
+       int ret;
 
        if (!pdev)
                return -EINVAL;
@@ -437,7 +439,7 @@ EXPORT_SYMBOL_GPL(platform_device_add);
  */
 void platform_device_del(struct platform_device *pdev)
 {
-       int i;
+       u32 i;
 
        if (pdev) {
                device_remove_properties(&pdev->dev);