From 204dd1d39c32f39a95bf7a7248f63b372fd137a6 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Tue, 7 Aug 2012 22:36:45 -0700 Subject: [PATCH] thermal: Fix potential NULL pointer accesses The type parameter in thermal_zone_device_register and thermal_cooling_device_register can be NULL, indicating that no sysfs attribute for the type should be created. Only call strlen() and strcpy() on type if it is not NULL. This patch addresses Coverity #102180 and #102182: Dereference before null check Signed-off-by: Guenter Roeck Signed-off-by: Zhang Rui --- drivers/thermal/thermal_sys.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/thermal/thermal_sys.c b/drivers/thermal/thermal_sys.c index 36e6f4d4ec3b..47498b871903 100644 --- a/drivers/thermal/thermal_sys.c +++ b/drivers/thermal/thermal_sys.c @@ -901,7 +901,7 @@ thermal_cooling_device_register(char *type, void *devdata, struct thermal_zone_device *pos; int result; - if (strlen(type) >= THERMAL_NAME_LENGTH) + if (type && strlen(type) >= THERMAL_NAME_LENGTH) return ERR_PTR(-EINVAL); if (!ops || !ops->get_max_state || !ops->get_cur_state || @@ -918,7 +918,7 @@ thermal_cooling_device_register(char *type, void *devdata, return ERR_PTR(result); } - strcpy(cdev->type, type); + strcpy(cdev->type, type ? : ""); mutex_init(&cdev->lock); INIT_LIST_HEAD(&cdev->thermal_instances); cdev->ops = ops; @@ -1344,7 +1344,7 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type, int count; int passive = 0; - if (strlen(type) >= THERMAL_NAME_LENGTH) + if (type && strlen(type) >= THERMAL_NAME_LENGTH) return ERR_PTR(-EINVAL); if (trips > THERMAL_MAX_TRIPS || trips < 0 || mask >> trips) @@ -1366,7 +1366,7 @@ struct thermal_zone_device *thermal_zone_device_register(const char *type, return ERR_PTR(result); } - strcpy(tz->type, type); + strcpy(tz->type, type ? : ""); tz->ops = ops; tz->device.class = &thermal_class; tz->devdata = devdata; -- 2.30.2