Re: [PATCH 1/2] regmap: fix NULL pointer dereference in regmap_name_read_file()

From: David Lechner
Date: Wed Jan 24 2018 - 11:27:27 EST


On 01/24/2018 10:19 AM, Mark Brown wrote:
On Wed, Jan 24, 2018 at 05:14:50PM +0100, Lars-Peter Clausen wrote:
On 01/23/2018 11:53 PM, David Lechner wrote:
This fixes a possible NULL pointer dereference oops in
regmap_name_read_file() when the regmap does not have a device
associated with it.

- ret = snprintf(buf, PAGE_SIZE, "%s\n", map->dev->driver->name);
+ if (map->dev && map->dev->driver)
+ name = map->dev->driver->name;
+
+ ret = snprintf(buf, PAGE_SIZE, "%s\n", name);

Won't this print "(null)" now? Not sure if that is the best approach.

Indeed. It is an improvement but not exactly helpful.



Would it be better if it said "this regmap does not have driver" instead
of "(null)"?