livepatch: fix format string in kobject_init_and_add()

kobject_init_and_add() takes expects format string for a name, so we
better provide it in order to avoid infoleaks if modules craft their
mod->name in a special way.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Reported-by: Kees Cook <keescook@chromium.org>
Acked-by: Seth Jennings <sjenning@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c
index ff7f47d..69bf3aa 100644 (file)
--- a/kernel/livepatch/core.c
+++ b/kernel/livepatch/core.c
@@ -731,7 +731,7 @@ static int klp_init_func(struct klp_object *obj, struct klp_func *func)
        func->state = KLP_DISABLED;
 
        return kobject_init_and_add(&func->kobj, &klp_ktype_func,
-                                   obj->kobj, func->old_name);
+                                   obj->kobj, "%s", func->old_name);
 }
 
 /* parts of the initialization that is done only when the object is loaded */
@@ -807,7 +807,7 @@ static int klp_init_patch(struct klp_patch *patch)
        patch->state = KLP_DISABLED;
 
        ret = kobject_init_and_add(&patch->kobj, &klp_ktype_patch,
-                                  klp_root_kobj, patch->mod->name);
+                                  klp_root_kobj, "%s", patch->mod->name);
        if (ret)
                goto unlock;