From: Xiubo Li Date: Sun, 28 Sep 2014 03:35:25 +0000 (+0800) Subject: regmap: debugfs: fix possbile NULL pointer dereference X-Git-Tag: firefly_0821_release~3679^2~1361 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d9aa4aecb2e94ca383789147769291e8723ecf86;p=firefly-linux-kernel-4.4.55.git regmap: debugfs: fix possbile NULL pointer dereference commit 2c98e0c1cc6b8e86f1978286c3d4e0769ee9d733 upstream. If 'map->dev' is NULL and there will lead dev_name() to be NULL pointer dereference. So before dev_name(), we need to have check of the map->dev pionter. We also should make sure that the 'name' pointer shouldn't be NULL for debugfs_create_dir(). So here using one default "dummy" debugfs name when the 'name' pointer and 'map->dev' are both NULL. Signed-off-by: Xiubo Li Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c index 975719bc3450..b41994fd8460 100644 --- a/drivers/base/regmap/regmap-debugfs.c +++ b/drivers/base/regmap/regmap-debugfs.c @@ -460,16 +460,20 @@ void regmap_debugfs_init(struct regmap *map, const char *name) { struct rb_node *next; struct regmap_range_node *range_node; + const char *devname = "dummy"; INIT_LIST_HEAD(&map->debugfs_off_cache); mutex_init(&map->cache_lock); + if (map->dev) + devname = dev_name(map->dev); + if (name) { map->debugfs_name = kasprintf(GFP_KERNEL, "%s-%s", - dev_name(map->dev), name); + devname, name); name = map->debugfs_name; } else { - name = dev_name(map->dev); + name = devname; } map->debugfs = debugfs_create_dir(name, regmap_debugfs_root);