Commit 5cfc64ce authored Sep 07, 2010 by Anton Vorontsov Committed by Greg Kroah-Hartman Oct 22, 2010

base/platform: Safe handling for NULL platform data and resources



Some users of platform_device_add_{data,resources}() assume that
NULL data and resources will be handled specially, i.e. just ignored.

But the platform core ends up calling kmemdup(NULL, 0, ...), which
returns a non-NULL result (i.e. ZERO_SIZE_PTR), which causes drivers
to oops on a valid code, something like:

  if (platform_data)
  	stuff = platform_data->stuff;

This patch makes the platform core a bit more safe for such cases.

Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent 87544653

drivers/base/platform.c

+8 −1

Original line number	Diff line number	Diff line
		@@ -192,6 +192,9 @@ int platform_device_add_resources(struct platform_device *pdev,
		{
		struct resource *r;

		if (!res)
		return 0;

		r = kmemdup(res, sizeof(struct resource) * num, GFP_KERNEL);
		if (r) {
		pdev->resource = r;
		@@ -215,8 +218,12 @@ EXPORT_SYMBOL_GPL(platform_device_add_resources);
		int platform_device_add_data(struct platform_device pdev, const void data,
		size_t size)
		{
		void *d = kmemdup(data, size, GFP_KERNEL);
		void *d;

		if (!data)
		return 0;

		d = kmemdup(data, size, GFP_KERNEL);
		if (d) {
		pdev->dev.platform_data = d;
		return 0;