drm/nouveau/therm: Move an assignment statement behind a null pointer check in two...

The address of a data structure member was determined before
a corresponding null pointer check in the implementation of
the functions “nvkm_fanpwm_create” and “nvkm_fantog_create”.

Thus avoid the risk for undefined behaviour by moving the assignment
for the data structure member “fan” behind two null pointer checks.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/3d0215dc-74d4-2c42-2eee-7a5fcf62b9f1@web.de

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/therm/fanpwm.c b/drivers/gpu/drm/nouveau/nvkm/subdev/therm/fanpwm.c
index 340f37a..b13ba9b 100644 (file)
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/therm/fanpwm.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/therm/fanpwm.c
@@ -98,10 +98,10 @@ nvkm_fanpwm_create(struct nvkm_therm *therm, struct dcb_gpio_func *func)
                return -ENODEV;
 
        fan = kzalloc(sizeof(*fan), GFP_KERNEL);
-       therm->fan = &fan->base;
        if (!fan)
                return -ENOMEM;
 
+       therm->fan = &fan->base;
        fan->base.type = "PWM";
        fan->base.get = nvkm_fanpwm_get;
        fan->base.set = nvkm_fanpwm_set;

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/therm/fantog.c b/drivers/gpu/drm/nouveau/nvkm/subdev/therm/fantog.c
index ff9fbe7..bfdf4ca 100644 (file)
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/therm/fantog.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/therm/fantog.c
@@ -100,10 +100,10 @@ nvkm_fantog_create(struct nvkm_therm *therm, struct dcb_gpio_func *func)
        }
 
        fan = kzalloc(sizeof(*fan), GFP_KERNEL);
-       therm->fan = &fan->base;
        if (!fan)
                return -ENOMEM;
 
+       therm->fan = &fan->base;
        fan->base.type = "toggle";
        fan->base.get = nvkm_fantog_get;
        fan->base.set = nvkm_fantog_set;