Commit 63f1e05f authored Dec 06, 2017 by Gustavo A. R. Silva Committed by MyungJoo Ham Jan 02, 2018

PM / devfreq: Fix potential NULL pointer dereference in governor_store



df->governor is being dereferenced before it is null checked,
hence there is a potential null pointer dereference.

Notice that df->governor is being null checked at line 1004:
if (df->governor) {, which implies it might be null.

Fix this by null checking df->governor before dereferencing it.

Addresses-Coverity-ID: 1401988 ("Dereference before null check")
Fixes: bcf23c79 ("PM / devfreq: Fix available_governor sysfs")
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>

parent d1bf2d30

drivers/devfreq/devfreq.c

+2 −1

Original line number	Original line	Diff line number	Diff line
	@@ -996,7 +996,8 @@ static ssize_t governor_store(struct device dev, struct device_attribute attr,
	if (df->governor == governor) {		if (df->governor == governor) {
	ret = 0;		ret = 0;
	goto out;		goto out;
	} else if (df->governor->immutable \|\| governor->immutable) {		} else if ((df->governor && df->governor->immutable) \|\|
			governor->immutable) {
	ret = -EINVAL;		ret = -EINVAL;
	goto out;		goto out;
	}		}