From d1bf2d30728f310f72296b54f0651ecdb09cbb12 Mon Sep 17 00:00:00 2001 From: Bjorn Andersson Date: Sun, 5 Nov 2017 21:27:41 -0800 Subject: [PATCH 1/2] PM / devfreq: Propagate error from devfreq_add_device() Propagate the error of devfreq_add_device() in devm_devfreq_add_device() rather than statically returning ENOMEM. This makes it slightly faster to pinpoint the cause of a returned error. Fixes: 8cd84092d35e ("PM / devfreq: Add resource-managed function for devfreq device") Cc: stable@vger.kernel.org Acked-by: Chanwoo Choi Signed-off-by: Bjorn Andersson Signed-off-by: MyungJoo Ham --- drivers/devfreq/devfreq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 78fb496ecb4e..99c4021fc33b 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -737,7 +737,7 @@ struct devfreq *devm_devfreq_add_device(struct device *dev, devfreq = devfreq_add_device(dev, profile, governor_name, data); if (IS_ERR(devfreq)) { devres_free(ptr); - return ERR_PTR(-ENOMEM); + return devfreq; } *ptr = devfreq; From 63f1e05f7fe9ca509c60154d6a833abf96eecdc9 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Wed, 6 Dec 2017 14:20:15 -0600 Subject: [PATCH 2/2] 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: bcf23c79c4e4 ("PM / devfreq: Fix available_governor sysfs") Signed-off-by: Gustavo A. R. Silva Reviewed-by: Chanwoo Choi Signed-off-by: MyungJoo Ham --- drivers/devfreq/devfreq.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index 99c4021fc33b..fe2af6aa88fc 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -996,7 +996,8 @@ static ssize_t governor_store(struct device *dev, struct device_attribute *attr, if (df->governor == governor) { ret = 0; goto out; - } else if (df->governor->immutable || governor->immutable) { + } else if ((df->governor && df->governor->immutable) || + governor->immutable) { ret = -EINVAL; goto out; }