From 449488ced03a3552b45d5993c06f6f3e422308b7 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: Zhang Rui Signed-off-by: Guenter Roeck --- 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; -- 2.39.5