1 files changed, 92 insertions, 88 deletions

diff --git a/kernel/module/sysfs.c b/kernel/module/sysfs.c
index d964167c6658..b401ff4b02d2 100644
--- a/kernel/module/sysfs.c
+++ b/kernel/module/sysfs.c
@@ -19,24 +19,16 @@
  * J. Corbet <corbet@lwn.net>
  */
 #ifdef CONFIG_KALLSYMS
-struct module_sect_attr {
-	struct bin_attribute battr;
-	unsigned long address;
-};
-
 struct module_sect_attrs {
 	struct attribute_group grp;
-	unsigned int nsections;
-	struct module_sect_attr attrs[];
+	struct bin_attribute attrs[];
 };
 
 #define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4))
 static ssize_t module_sect_read(struct file *file, struct kobject *kobj,
-				struct bin_attribute *battr,
+				const struct bin_attribute *battr,
 				char *buf, loff_t pos, size_t count)
 {
-	struct module_sect_attr *sattr =
-		container_of(battr, struct module_sect_attr, battr);
 	char bounce[MODULE_SECT_READ_SIZE + 1];
 	size_t wrote;
 
@@ -53,7 +45,7 @@ static ssize_t module_sect_read(struct file *file, struct kobject *kobj,
 	 */
 	wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n",
 			  kallsyms_show_value(file->f_cred)
-				? (void *)sattr->address : NULL);
+				? battr->private : NULL);
 	count = min(count, wrote);
 	memcpy(buf, bounce, count);
 
@@ -62,64 +54,69 @@ static ssize_t module_sect_read(struct file *file, struct kobject *kobj,
 
 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
 {
-	unsigned int section;
+	const struct bin_attribute *const *bin_attr;
 
-	for (section = 0; section < sect_attrs->nsections; section++)
-		kfree(sect_attrs->attrs[section].battr.attr.name);
+	for (bin_attr = sect_attrs->grp.bin_attrs_new; *bin_attr; bin_attr++)
+		kfree((*bin_attr)->attr.name);
+	kfree(sect_attrs->grp.bin_attrs_new);
 	kfree(sect_attrs);
 }
 
-static void add_sect_attrs(struct module *mod, const struct load_info *info)
+static int add_sect_attrs(struct module *mod, const struct load_info *info)
 {
-	unsigned int nloaded = 0, i, size[2];
 	struct module_sect_attrs *sect_attrs;
-	struct module_sect_attr *sattr;
-	struct bin_attribute **gattr;
+	const struct bin_attribute **gattr;
+	struct bin_attribute *sattr;
+	unsigned int nloaded = 0, i;
+	int ret;
 
 	/* Count loaded sections and allocate structures */
 	for (i = 0; i < info->hdr->e_shnum; i++)
 		if (!sect_empty(&info->sechdrs[i]))
 			nloaded++;
-	size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded),
-			sizeof(sect_attrs->grp.bin_attrs[0]));
-	size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]);
-	sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
+	sect_attrs = kzalloc(struct_size(sect_attrs, attrs, nloaded), GFP_KERNEL);
 	if (!sect_attrs)
-		return;
+		return -ENOMEM;
+
+	gattr = kcalloc(nloaded + 1, sizeof(*gattr), GFP_KERNEL);
+	if (!gattr) {
+		kfree(sect_attrs);
+		return -ENOMEM;
+	}
 
 	/* Setup section attributes. */
 	sect_attrs->grp.name = "sections";
-	sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0];
+	sect_attrs->grp.bin_attrs_new = gattr;
 
-	sect_attrs->nsections = 0;
 	sattr = &sect_attrs->attrs[0];
-	gattr = &sect_attrs->grp.bin_attrs[0];
 	for (i = 0; i < info->hdr->e_shnum; i++) {
 		Elf_Shdr *sec = &info->sechdrs[i];
 
 		if (sect_empty(sec))
 			continue;
-		sysfs_bin_attr_init(&sattr->battr);
-		sattr->address = sec->sh_addr;
-		sattr->battr.attr.name =
+		sysfs_bin_attr_init(sattr);
+		sattr->attr.name =
 			kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL);
-		if (!sattr->battr.attr.name)
+		if (!sattr->attr.name) {
+			ret = -ENOMEM;
 			goto out;
-		sect_attrs->nsections++;
-		sattr->battr.read = module_sect_read;
-		sattr->battr.size = MODULE_SECT_READ_SIZE;
-		sattr->battr.attr.mode = 0400;
-		*(gattr++) = &(sattr++)->battr;
+		}
+		sattr->read_new = module_sect_read;
+		sattr->private = (void *)sec->sh_addr;
+		sattr->size = MODULE_SECT_READ_SIZE;
+		sattr->attr.mode = 0400;
+		*(gattr++) = sattr++;
 	}
-	*gattr = NULL;
 
-	if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
+	ret = sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp);
+	if (ret)
 		goto out;
 
 	mod->sect_attrs = sect_attrs;
-	return;
+	return 0;
 out:
 	free_sect_attrs(sect_attrs);
+	return ret;
 }
 
 static void remove_sect_attrs(struct module *mod)
@@ -141,43 +138,23 @@ static void remove_sect_attrs(struct module *mod)
  */
 
 struct module_notes_attrs {
-	struct kobject *dir;
-	unsigned int notes;
-	struct bin_attribute attrs[] __counted_by(notes);
+	struct attribute_group grp;
+	struct bin_attribute attrs[];
 };
 
-static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
-				 struct bin_attribute *bin_attr,
-				 char *buf, loff_t pos, size_t count)
+static void free_notes_attrs(struct module_notes_attrs *notes_attrs)
 {
-	/*
-	 * The caller checked the pos and count against our size.
-	 */
-	memcpy(buf, bin_attr->private + pos, count);
-	return count;
-}
-
-static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
-			     unsigned int i)
-{
-	if (notes_attrs->dir) {
-		while (i-- > 0)
-			sysfs_remove_bin_file(notes_attrs->dir,
-					      &notes_attrs->attrs[i]);
-		kobject_put(notes_attrs->dir);
-	}
+	kfree(notes_attrs->grp.bin_attrs_new);
 	kfree(notes_attrs);
 }
 
-static void add_notes_attrs(struct module *mod, const struct load_info *info)
+static int add_notes_attrs(struct module *mod, const struct load_info *info)
 {
 	unsigned int notes, loaded, i;
 	struct module_notes_attrs *notes_attrs;
+	const struct bin_attribute **gattr;
 	struct bin_attribute *nattr;
-
-	/* failed to create section attributes, so can't create notes */
-	if (!mod->sect_attrs)
-		return;
+	int ret;
 
 	/* Count notes sections and allocate structures.  */
 	notes = 0;
@@ -187,56 +164,74 @@ static void add_notes_attrs(struct module *mod, const struct load_info *info)
 			++notes;
 
 	if (notes == 0)
-		return;
+		return 0;
 
 	notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes),
 			      GFP_KERNEL);
 	if (!notes_attrs)
-		return;
+		return -ENOMEM;
+
+	gattr = kcalloc(notes + 1, sizeof(*gattr), GFP_KERNEL);
+	if (!gattr) {
+		kfree(notes_attrs);
+		return -ENOMEM;
+	}
+
+	notes_attrs->grp.name = "notes";
+	notes_attrs->grp.bin_attrs_new = gattr;
 
-	notes_attrs->notes = notes;
 	nattr = &notes_attrs->attrs[0];
 	for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
 		if (sect_empty(&info->sechdrs[i]))
 			continue;
 		if (info->sechdrs[i].sh_type == SHT_NOTE) {
 			sysfs_bin_attr_init(nattr);
-			nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name;
+			nattr->attr.name = mod->sect_attrs->attrs[loaded].attr.name;
 			nattr->attr.mode = 0444;
 			nattr->size = info->sechdrs[i].sh_size;
 			nattr->private = (void *)info->sechdrs[i].sh_addr;
-			nattr->read = module_notes_read;
-			++nattr;
+			nattr->read_new = sysfs_bin_attr_simple_read;
+			*(gattr++) = nattr++;
 		}
 		++loaded;
 	}
 
-	notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
-	if (!notes_attrs->dir)
+	ret = sysfs_create_group(&mod->mkobj.kobj, &notes_attrs->grp);
+	if (ret)
 		goto out;
 
-	for (i = 0; i < notes; ++i)
-		if (sysfs_create_bin_file(notes_attrs->dir,
-					  &notes_attrs->attrs[i]))
-			goto out;
-
 	mod->notes_attrs = notes_attrs;
-	return;
+	return 0;
 
 out:
-	free_notes_attrs(notes_attrs, i);
+	free_notes_attrs(notes_attrs);
+	return ret;
 }
 
 static void remove_notes_attrs(struct module *mod)
 {
-	if (mod->notes_attrs)
-		free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
+	if (mod->notes_attrs) {
+		sysfs_remove_group(&mod->mkobj.kobj,
+				   &mod->notes_attrs->grp);
+		/*
+		 * We are positive that no one is using any notes attrs
+		 * at this point.  Deallocate immediately.
+		 */
+		free_notes_attrs(mod->notes_attrs);
+		mod->notes_attrs = NULL;
+	}
 }
 
 #else /* !CONFIG_KALLSYMS */
-static inline void add_sect_attrs(struct module *mod, const struct load_info *info) { }
+static inline int add_sect_attrs(struct module *mod, const struct load_info *info)
+{
+	return 0;
+}
 static inline void remove_sect_attrs(struct module *mod) { }
-static inline void add_notes_attrs(struct module *mod, const struct load_info *info) { }
+static inline int add_notes_attrs(struct module *mod, const struct load_info *info)
+{
+	return 0;
+}
 static inline void remove_notes_attrs(struct module *mod) { }
 #endif /* CONFIG_KALLSYMS */
 
@@ -274,7 +269,7 @@ static int add_usage_links(struct module *mod)
 
 static void module_remove_modinfo_attrs(struct module *mod, int end)
 {
-	struct module_attribute *attr;
+	const struct module_attribute *attr;
 	int i;
 
 	for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
@@ -292,7 +287,7 @@ static void module_remove_modinfo_attrs(struct module *mod, int end)
 
 static int module_add_modinfo_attrs(struct module *mod)
 {
-	struct module_attribute *attr;
+	const struct module_attribute *attr;
 	struct module_attribute *temp_attr;
 	int error = 0;
 	int i;
@@ -396,11 +391,20 @@ int mod_sysfs_setup(struct module *mod,
 	if (err)
 		goto out_unreg_modinfo_attrs;
 
-	add_sect_attrs(mod, info);
-	add_notes_attrs(mod, info);
+	err = add_sect_attrs(mod, info);
+	if (err)
+		goto out_del_usage_links;
+
+	err = add_notes_attrs(mod, info);
+	if (err)
+		goto out_unreg_sect_attrs;
 
 	return 0;
 
+out_unreg_sect_attrs:
+	remove_sect_attrs(mod);
+out_del_usage_links:
+	del_usage_links(mod);
 out_unreg_modinfo_attrs:
 	module_remove_modinfo_attrs(mod, -1);
 out_unreg_param: