[PATCH AUTOSEL 4.19 162/252] driver core: platform: Prevent resouce overflow from causing infinite loops

From: Sasha Levin
Date: Fri Feb 14 2020 - 12:05:03 EST


From: Simon Schwartz <kern.simon@xxxxxxxxxxxxxxx>

[ 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@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/2201ce63a2a171ffd2ed14e867875316efcf71db.camel@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/base/platform.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index e9be1f56929af..1d3a50ac21664 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -27,6 +27,7 @@
#include <linux/limits.h>
#include <linux/property.h>
#include <linux/kmemleak.h>
+#include <linux/types.h>

#include "base.h"
#include "power/power.h"
@@ -67,7 +68,7 @@ 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];
@@ -162,7 +163,7 @@ 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];
@@ -359,7 +360,8 @@ 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;
@@ -446,7 +448,7 @@ 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);
--
2.20.1