2022-02-19 00:57:48

by Aaron Tomlin

[permalink] [raw]
Subject: [PATCH v6 11/13] module: Move sysfs support into a separate file

No functional change.

This patch migrates module sysfs support out of core code into
kernel/module/sysfs.c. In addition simple code refactoring to
make this possible.

Signed-off-by: Aaron Tomlin <[email protected]>
---
kernel/module/Makefile | 1 +
kernel/module/internal.h | 21 ++
kernel/module/main.c | 469 +--------------------------------------
kernel/module/sysfs.c | 436 ++++++++++++++++++++++++++++++++++++
4 files changed, 461 insertions(+), 466 deletions(-)
create mode 100644 kernel/module/sysfs.c

diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index f66fda0b41cc..a3cbe09ce2b2 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -14,4 +14,5 @@ obj-$(CONFIG_STRICT_MODULE_RWX) += strict_rwx.o
obj-$(CONFIG_DEBUG_KMEMLEAK) += debug_kmemleak.o
obj-$(CONFIG_KALLSYMS) += kallsyms.o
obj-$(CONFIG_PROC_FS) += procfs.o
+obj-$(CONFIG_SYSFS) += sysfs.o
endif
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index ddb37024a0d6..74096cca742c 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -34,6 +34,9 @@
extern struct mutex module_mutex;
extern struct list_head modules;

+extern struct module_attribute *modinfo_attrs[];
+extern size_t modinfo_attrs_count;
+
/* Provided by the linker */
extern const struct kernel_symbol __start___ksymtab[];
extern const struct kernel_symbol __stop___ksymtab[];
@@ -213,3 +216,21 @@ static inline bool sect_empty(const Elf_Shdr *sect)
static inline void layout_symtab(struct module *mod, struct load_info *info) { }
static inline void add_kallsyms(struct module *mod, const struct load_info *info) { }
#endif /* CONFIG_KALLSYMS */
+
+#ifdef CONFIG_SYSFS
+int mod_sysfs_setup(struct module *mod, const struct load_info *info,
+ struct kernel_param *kparam, unsigned int num_params);
+void mod_sysfs_teardown(struct module *mod);
+void init_param_lock(struct module *mod);
+#else /* !CONFIG_SYSFS */
+static inline int mod_sysfs_setup(struct module *mod,
+ const struct load_info *info,
+ struct kernel_param *kparam,
+ unsigned int num_params)
+{
+ return 0;
+}
+
+static inline void mod_sysfs_teardown(struct module *mod) { }
+static inline void init_param_lock(struct module *mod) { }
+#endif /* CONFIG_SYSFS */
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 44b6fd1acc44..b8a59b5c3e3a 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -14,9 +14,7 @@
#include <linux/init.h>
#include <linux/kallsyms.h>
#include <linux/buildid.h>
-#include <linux/file.h>
#include <linux/fs.h>
-#include <linux/sysfs.h>
#include <linux/kernel.h>
#include <linux/kernel_read_file.h>
#include <linux/slab.h>
@@ -989,7 +987,7 @@ static ssize_t show_taint(struct module_attribute *mattr,
static struct module_attribute modinfo_taint =
__ATTR(taint, 0444, show_taint, NULL);

-static struct module_attribute *modinfo_attrs[] = {
+struct module_attribute *modinfo_attrs[] = {
&module_uevent,
&modinfo_version,
&modinfo_srcversion,
@@ -1003,6 +1001,8 @@ static struct module_attribute *modinfo_attrs[] = {
NULL,
};

+size_t modinfo_attrs_count = ARRAY_SIZE(modinfo_attrs);
+
static const char vermagic[] = VERMAGIC_STRING;

static int try_to_force_load(struct module *mod, const char *reason)
@@ -1253,469 +1253,6 @@ resolve_symbol_wait(struct module *mod,
return ksym;
}

-/*
- * /sys/module/foo/sections stuff
- * J. Corbet <[email protected]>
- */
-#ifdef CONFIG_SYSFS
-
-#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[];
-};
-
-#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,
- 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;
-
- if (pos != 0)
- return -EINVAL;
-
- /*
- * Since we're a binary read handler, we must account for the
- * trailing NUL byte that sprintf will write: if "buf" is
- * too small to hold the NUL, or the NUL is exactly the last
- * byte, the read will look like it got truncated by one byte.
- * Since there is no way to ask sprintf nicely to not write
- * the NUL, we have to use a bounce buffer.
- */
- wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n",
- kallsyms_show_value(file->f_cred)
- ? (void *)sattr->address : NULL);
- count = min(count, wrote);
- memcpy(buf, bounce, count);
-
- return count;
-}
-
-static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
-{
- unsigned int section;
-
- for (section = 0; section < sect_attrs->nsections; section++)
- kfree(sect_attrs->attrs[section].battr.attr.name);
- kfree(sect_attrs);
-}
-
-static void 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;
-
- /* 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);
- if (sect_attrs == NULL)
- return;
-
- /* Setup section attributes. */
- sect_attrs->grp.name = "sections";
- sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0];
-
- 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 =
- kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL);
- if (sattr->battr.attr.name == NULL)
- 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;
- }
- *gattr = NULL;
-
- if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
- goto out;
-
- mod->sect_attrs = sect_attrs;
- return;
- out:
- free_sect_attrs(sect_attrs);
-}
-
-static void remove_sect_attrs(struct module *mod)
-{
- if (mod->sect_attrs) {
- sysfs_remove_group(&mod->mkobj.kobj,
- &mod->sect_attrs->grp);
- /*
- * We are positive that no one is using any sect attrs
- * at this point. Deallocate immediately.
- */
- free_sect_attrs(mod->sect_attrs);
- mod->sect_attrs = NULL;
- }
-}
-
-/*
- * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
- */
-
-struct module_notes_attrs {
- struct kobject *dir;
- unsigned int notes;
- 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)
-{
- /*
- * 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);
-}
-
-static void add_notes_attrs(struct module *mod, const struct load_info *info)
-{
- unsigned int notes, loaded, i;
- struct module_notes_attrs *notes_attrs;
- struct bin_attribute *nattr;
-
- /* failed to create section attributes, so can't create notes */
- if (!mod->sect_attrs)
- return;
-
- /* Count notes sections and allocate structures. */
- notes = 0;
- for (i = 0; i < info->hdr->e_shnum; i++)
- if (!sect_empty(&info->sechdrs[i]) &&
- (info->sechdrs[i].sh_type == SHT_NOTE))
- ++notes;
-
- if (notes == 0)
- return;
-
- notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes),
- GFP_KERNEL);
- if (notes_attrs == NULL)
- return;
-
- 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.mode = S_IRUGO;
- nattr->size = info->sechdrs[i].sh_size;
- nattr->private = (void *) info->sechdrs[i].sh_addr;
- nattr->read = module_notes_read;
- ++nattr;
- }
- ++loaded;
- }
-
- notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
- if (!notes_attrs->dir)
- 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;
-
- out:
- free_notes_attrs(notes_attrs, i);
-}
-
-static void remove_notes_attrs(struct module *mod)
-{
- if (mod->notes_attrs)
- free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
-}
-
-#else
-
-static inline void add_sect_attrs(struct module *mod,
- const struct load_info *info)
-{
-}
-
-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 void remove_notes_attrs(struct module *mod)
-{
-}
-#endif /* CONFIG_KALLSYMS */
-
-static void del_usage_links(struct module *mod)
-{
-#ifdef CONFIG_MODULE_UNLOAD
- struct module_use *use;
-
- mutex_lock(&module_mutex);
- list_for_each_entry(use, &mod->target_list, target_list)
- sysfs_remove_link(use->target->holders_dir, mod->name);
- mutex_unlock(&module_mutex);
-#endif
-}
-
-static int add_usage_links(struct module *mod)
-{
- int ret = 0;
-#ifdef CONFIG_MODULE_UNLOAD
- struct module_use *use;
-
- mutex_lock(&module_mutex);
- list_for_each_entry(use, &mod->target_list, target_list) {
- ret = sysfs_create_link(use->target->holders_dir,
- &mod->mkobj.kobj, mod->name);
- if (ret)
- break;
- }
- mutex_unlock(&module_mutex);
- if (ret)
- del_usage_links(mod);
-#endif
- return ret;
-}
-
-static void module_remove_modinfo_attrs(struct module *mod, int end);
-
-static int module_add_modinfo_attrs(struct module *mod)
-{
- struct module_attribute *attr;
- struct module_attribute *temp_attr;
- int error = 0;
- int i;
-
- mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
- (ARRAY_SIZE(modinfo_attrs) + 1)),
- GFP_KERNEL);
- if (!mod->modinfo_attrs)
- return -ENOMEM;
-
- temp_attr = mod->modinfo_attrs;
- for (i = 0; (attr = modinfo_attrs[i]); i++) {
- if (!attr->test || attr->test(mod)) {
- memcpy(temp_attr, attr, sizeof(*temp_attr));
- sysfs_attr_init(&temp_attr->attr);
- error = sysfs_create_file(&mod->mkobj.kobj,
- &temp_attr->attr);
- if (error)
- goto error_out;
- ++temp_attr;
- }
- }
-
- return 0;
-
-error_out:
- if (i > 0)
- module_remove_modinfo_attrs(mod, --i);
- else
- kfree(mod->modinfo_attrs);
- return error;
-}
-
-static void module_remove_modinfo_attrs(struct module *mod, int end)
-{
- struct module_attribute *attr;
- int i;
-
- for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
- if (end >= 0 && i > end)
- break;
- /* pick a field to test for end of list */
- if (!attr->attr.name)
- break;
- sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
- if (attr->free)
- attr->free(mod);
- }
- kfree(mod->modinfo_attrs);
-}
-
-static void mod_kobject_put(struct module *mod)
-{
- DECLARE_COMPLETION_ONSTACK(c);
- mod->mkobj.kobj_completion = &c;
- kobject_put(&mod->mkobj.kobj);
- wait_for_completion(&c);
-}
-
-static int mod_sysfs_init(struct module *mod)
-{
- int err;
- struct kobject *kobj;
-
- if (!module_sysfs_initialized) {
- pr_err("%s: module sysfs not initialized\n", mod->name);
- err = -EINVAL;
- goto out;
- }
-
- kobj = kset_find_obj(module_kset, mod->name);
- if (kobj) {
- pr_err("%s: module is already loaded\n", mod->name);
- kobject_put(kobj);
- err = -EINVAL;
- goto out;
- }
-
- mod->mkobj.mod = mod;
-
- memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
- mod->mkobj.kobj.kset = module_kset;
- err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
- "%s", mod->name);
- if (err)
- mod_kobject_put(mod);
-
-out:
- return err;
-}
-
-static int mod_sysfs_setup(struct module *mod,
- const struct load_info *info,
- struct kernel_param *kparam,
- unsigned int num_params)
-{
- int err;
-
- err = mod_sysfs_init(mod);
- if (err)
- goto out;
-
- mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
- if (!mod->holders_dir) {
- err = -ENOMEM;
- goto out_unreg;
- }
-
- err = module_param_sysfs_setup(mod, kparam, num_params);
- if (err)
- goto out_unreg_holders;
-
- err = module_add_modinfo_attrs(mod);
- if (err)
- goto out_unreg_param;
-
- err = add_usage_links(mod);
- if (err)
- goto out_unreg_modinfo_attrs;
-
- add_sect_attrs(mod, info);
- add_notes_attrs(mod, info);
-
- return 0;
-
-out_unreg_modinfo_attrs:
- module_remove_modinfo_attrs(mod, -1);
-out_unreg_param:
- module_param_sysfs_remove(mod);
-out_unreg_holders:
- kobject_put(mod->holders_dir);
-out_unreg:
- mod_kobject_put(mod);
-out:
- return err;
-}
-
-static void mod_sysfs_fini(struct module *mod)
-{
- remove_notes_attrs(mod);
- remove_sect_attrs(mod);
- mod_kobject_put(mod);
-}
-
-static void init_param_lock(struct module *mod)
-{
- mutex_init(&mod->param_lock);
-}
-#else /* !CONFIG_SYSFS */
-
-static int mod_sysfs_setup(struct module *mod,
- const struct load_info *info,
- struct kernel_param *kparam,
- unsigned int num_params)
-{
- return 0;
-}
-
-static void mod_sysfs_fini(struct module *mod)
-{
-}
-
-static void module_remove_modinfo_attrs(struct module *mod, int end)
-{
-}
-
-static void del_usage_links(struct module *mod)
-{
-}
-
-static void init_param_lock(struct module *mod)
-{
-}
-#endif /* CONFIG_SYSFS */
-
-static void mod_sysfs_teardown(struct module *mod)
-{
- del_usage_links(mod);
- module_remove_modinfo_attrs(mod, -1);
- module_param_sysfs_remove(mod);
- kobject_put(mod->mkobj.drivers_dir);
- kobject_put(mod->holders_dir);
- mod_sysfs_fini(mod);
-}
-
/*
* LKM RO/NX protection: protect module's text/ro-data
* from modification and any data from execution.
diff --git a/kernel/module/sysfs.c b/kernel/module/sysfs.c
new file mode 100644
index 000000000000..ce68f821dcd1
--- /dev/null
+++ b/kernel/module/sysfs.c
@@ -0,0 +1,436 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Module sysfs support
+ *
+ * Copyright (C) 2008 Rusty Russell
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/sysfs.h>
+#include <linux/slab.h>
+#include <linux/kallsyms.h>
+#include <linux/mutex.h>
+#include "internal.h"
+
+/*
+ * /sys/module/foo/sections stuff
+ * J. Corbet <[email protected]>
+ */
+#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[];
+};
+
+#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,
+ 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;
+
+ if (pos != 0)
+ return -EINVAL;
+
+ /*
+ * Since we're a binary read handler, we must account for the
+ * trailing NUL byte that sprintf will write: if "buf" is
+ * too small to hold the NUL, or the NUL is exactly the last
+ * byte, the read will look like it got truncated by one byte.
+ * Since there is no way to ask sprintf nicely to not write
+ * the NUL, we have to use a bounce buffer.
+ */
+ wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n",
+ kallsyms_show_value(file->f_cred)
+ ? (void *)sattr->address : NULL);
+ count = min(count, wrote);
+ memcpy(buf, bounce, count);
+
+ return count;
+}
+
+static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
+{
+ unsigned int section;
+
+ for (section = 0; section < sect_attrs->nsections; section++)
+ kfree(sect_attrs->attrs[section].battr.attr.name);
+ kfree(sect_attrs);
+}
+
+static void 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;
+
+ /* 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);
+ if (!sect_attrs)
+ return;
+
+ /* Setup section attributes. */
+ sect_attrs->grp.name = "sections";
+ sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0];
+
+ 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 =
+ kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL);
+ if (!sattr->battr.attr.name)
+ 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;
+ }
+ *gattr = NULL;
+
+ if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
+ goto out;
+
+ mod->sect_attrs = sect_attrs;
+ return;
+out:
+ free_sect_attrs(sect_attrs);
+}
+
+static void remove_sect_attrs(struct module *mod)
+{
+ if (mod->sect_attrs) {
+ sysfs_remove_group(&mod->mkobj.kobj,
+ &mod->sect_attrs->grp);
+ /*
+ * We are positive that no one is using any sect attrs
+ * at this point. Deallocate immediately.
+ */
+ free_sect_attrs(mod->sect_attrs);
+ mod->sect_attrs = NULL;
+ }
+}
+
+/*
+ * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
+ */
+
+struct module_notes_attrs {
+ struct kobject *dir;
+ unsigned int notes;
+ 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)
+{
+ /*
+ * 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);
+}
+
+static void add_notes_attrs(struct module *mod, const struct load_info *info)
+{
+ unsigned int notes, loaded, i;
+ struct module_notes_attrs *notes_attrs;
+ struct bin_attribute *nattr;
+
+ /* failed to create section attributes, so can't create notes */
+ if (!mod->sect_attrs)
+ return;
+
+ /* Count notes sections and allocate structures. */
+ notes = 0;
+ for (i = 0; i < info->hdr->e_shnum; i++)
+ if (!sect_empty(&info->sechdrs[i]) &&
+ info->sechdrs[i].sh_type == SHT_NOTE)
+ ++notes;
+
+ if (notes == 0)
+ return;
+
+ notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes),
+ GFP_KERNEL);
+ if (!notes_attrs)
+ return;
+
+ 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.mode = 0444;
+ nattr->size = info->sechdrs[i].sh_size;
+ nattr->private = (void *)info->sechdrs[i].sh_addr;
+ nattr->read = module_notes_read;
+ ++nattr;
+ }
+ ++loaded;
+ }
+
+ notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
+ if (!notes_attrs->dir)
+ 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;
+
+out:
+ free_notes_attrs(notes_attrs, i);
+}
+
+static void remove_notes_attrs(struct module *mod)
+{
+ if (mod->notes_attrs)
+ free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
+}
+
+#else /* !CONFIG_KALLSYMS */
+static inline void add_sect_attrs(struct module *mod, const struct load_info *info) { }
+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 void remove_notes_attrs(struct module *mod) { }
+#endif /* CONFIG_KALLSYMS */
+
+static void del_usage_links(struct module *mod)
+{
+#ifdef CONFIG_MODULE_UNLOAD
+ struct module_use *use;
+
+ mutex_lock(&module_mutex);
+ list_for_each_entry(use, &mod->target_list, target_list)
+ sysfs_remove_link(use->target->holders_dir, mod->name);
+ mutex_unlock(&module_mutex);
+#endif
+}
+
+static int add_usage_links(struct module *mod)
+{
+ int ret = 0;
+#ifdef CONFIG_MODULE_UNLOAD
+ struct module_use *use;
+
+ mutex_lock(&module_mutex);
+ list_for_each_entry(use, &mod->target_list, target_list) {
+ ret = sysfs_create_link(use->target->holders_dir,
+ &mod->mkobj.kobj, mod->name);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&module_mutex);
+ if (ret)
+ del_usage_links(mod);
+#endif
+ return ret;
+}
+
+static void module_remove_modinfo_attrs(struct module *mod, int end)
+{
+ struct module_attribute *attr;
+ int i;
+
+ for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
+ if (end >= 0 && i > end)
+ break;
+ /* pick a field to test for end of list */
+ if (!attr->attr.name)
+ break;
+ sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
+ if (attr->free)
+ attr->free(mod);
+ }
+ kfree(mod->modinfo_attrs);
+}
+
+static int module_add_modinfo_attrs(struct module *mod)
+{
+ struct module_attribute *attr;
+ struct module_attribute *temp_attr;
+ int error = 0;
+ int i;
+
+ mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
+ (modinfo_attrs_count + 1)),
+ GFP_KERNEL);
+ if (!mod->modinfo_attrs)
+ return -ENOMEM;
+
+ temp_attr = mod->modinfo_attrs;
+ for (i = 0; (attr = modinfo_attrs[i]); i++) {
+ if (!attr->test || attr->test(mod)) {
+ memcpy(temp_attr, attr, sizeof(*temp_attr));
+ sysfs_attr_init(&temp_attr->attr);
+ error = sysfs_create_file(&mod->mkobj.kobj,
+ &temp_attr->attr);
+ if (error)
+ goto error_out;
+ ++temp_attr;
+ }
+ }
+
+ return 0;
+
+error_out:
+ if (i > 0)
+ module_remove_modinfo_attrs(mod, --i);
+ else
+ kfree(mod->modinfo_attrs);
+ return error;
+}
+
+static void mod_kobject_put(struct module *mod)
+{
+ DECLARE_COMPLETION_ONSTACK(c);
+
+ mod->mkobj.kobj_completion = &c;
+ kobject_put(&mod->mkobj.kobj);
+ wait_for_completion(&c);
+}
+
+static int mod_sysfs_init(struct module *mod)
+{
+ int err;
+ struct kobject *kobj;
+
+ if (!module_sysfs_initialized) {
+ pr_err("%s: module sysfs not initialized\n", mod->name);
+ err = -EINVAL;
+ goto out;
+ }
+
+ kobj = kset_find_obj(module_kset, mod->name);
+ if (kobj) {
+ pr_err("%s: module is already loaded\n", mod->name);
+ kobject_put(kobj);
+ err = -EINVAL;
+ goto out;
+ }
+
+ mod->mkobj.mod = mod;
+
+ memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
+ mod->mkobj.kobj.kset = module_kset;
+ err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
+ "%s", mod->name);
+ if (err)
+ mod_kobject_put(mod);
+
+out:
+ return err;
+}
+
+int mod_sysfs_setup(struct module *mod,
+ const struct load_info *info,
+ struct kernel_param *kparam,
+ unsigned int num_params)
+{
+ int err;
+
+ err = mod_sysfs_init(mod);
+ if (err)
+ goto out;
+
+ mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
+ if (!mod->holders_dir) {
+ err = -ENOMEM;
+ goto out_unreg;
+ }
+
+ err = module_param_sysfs_setup(mod, kparam, num_params);
+ if (err)
+ goto out_unreg_holders;
+
+ err = module_add_modinfo_attrs(mod);
+ if (err)
+ goto out_unreg_param;
+
+ err = add_usage_links(mod);
+ if (err)
+ goto out_unreg_modinfo_attrs;
+
+ add_sect_attrs(mod, info);
+ add_notes_attrs(mod, info);
+
+ return 0;
+
+out_unreg_modinfo_attrs:
+ module_remove_modinfo_attrs(mod, -1);
+out_unreg_param:
+ module_param_sysfs_remove(mod);
+out_unreg_holders:
+ kobject_put(mod->holders_dir);
+out_unreg:
+ mod_kobject_put(mod);
+out:
+ return err;
+}
+
+static void mod_sysfs_fini(struct module *mod)
+{
+ remove_notes_attrs(mod);
+ remove_sect_attrs(mod);
+ mod_kobject_put(mod);
+}
+
+void mod_sysfs_teardown(struct module *mod)
+{
+ del_usage_links(mod);
+ module_remove_modinfo_attrs(mod, -1);
+ module_param_sysfs_remove(mod);
+ kobject_put(mod->mkobj.drivers_dir);
+ kobject_put(mod->holders_dir);
+ mod_sysfs_fini(mod);
+}
+
+void init_param_lock(struct module *mod)
+{
+ mutex_init(&mod->param_lock);
+}
--
2.34.1


2022-02-20 02:47:52

by Aaron Tomlin

[permalink] [raw]
Subject: [PATCH v6 13/13] module: Move version support into a separate file

No functional change.

This patch migrates module version support out of core code into
kernel/module/version.c. In addition simple code refactoring to
make this possible.

Signed-off-by: Aaron Tomlin <[email protected]>
---
kernel/module/Makefile | 1 +
kernel/module/internal.h | 48 ++++++++++++
kernel/module/main.c | 156 ++-------------------------------------
kernel/module/version.c | 109 +++++++++++++++++++++++++++
4 files changed, 166 insertions(+), 148 deletions(-)
create mode 100644 kernel/module/version.c

diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index a3cbe09ce2b2..686ca921fc8f 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -15,4 +15,5 @@ obj-$(CONFIG_DEBUG_KMEMLEAK) += debug_kmemleak.o
obj-$(CONFIG_KALLSYMS) += kallsyms.o
obj-$(CONFIG_PROC_FS) += procfs.o
obj-$(CONFIG_SYSFS) += sysfs.o
+obj-$(CONFIG_MODVERSIONS) += version.o
endif
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index 74096cca742c..47353c2e595b 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -70,7 +70,27 @@ struct load_info {
} index;
};

+enum mod_license {
+ NOT_GPL_ONLY,
+ GPL_ONLY,
+};
+
+struct find_symbol_arg {
+ /* Input */
+ const char *name;
+ bool gplok;
+ bool warn;
+
+ /* Output */
+ struct module *owner;
+ const s32 *crc;
+ const struct kernel_symbol *sym;
+ enum mod_license license;
+};
+
int mod_verify_sig(const void *mod, struct load_info *info);
+int try_to_force_load(struct module *mod, const char *reason);
+bool find_symbol(struct find_symbol_arg *fsa);
struct module *find_module_all(const char *name, size_t len, bool even_unformed);
int cmp_name(const void *name, const void *sym);
long module_get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr,
@@ -234,3 +254,31 @@ static inline int mod_sysfs_setup(struct module *mod,
static inline void mod_sysfs_teardown(struct module *mod) { }
static inline void init_param_lock(struct module *mod) { }
#endif /* CONFIG_SYSFS */
+
+#ifdef CONFIG_MODVERSIONS
+int check_version(const struct load_info *info,
+ const char *symname, struct module *mod, const s32 *crc);
+void module_layout(struct module *mod, struct modversion_info *ver, struct kernel_param *kp,
+ struct kernel_symbol *ks, struct tracepoint * const *tp);
+int check_modstruct_version(const struct load_info *info, struct module *mod);
+int same_magic(const char *amagic, const char *bmagic, bool has_crcs);
+#else /* !CONFIG_MODVERSIONS */
+static inline int check_version(const struct load_info *info,
+ const char *symname,
+ struct module *mod,
+ const s32 *crc)
+{
+ return 1;
+}
+
+static inline int check_modstruct_version(const struct load_info *info,
+ struct module *mod)
+{
+ return 1;
+}
+
+static inline int same_magic(const char *amagic, const char *bmagic, bool has_crcs)
+{
+ return strcmp(amagic, bmagic) == 0;
+}
+#endif /* CONFIG_MODVERSIONS */
diff --git a/kernel/module/main.c b/kernel/module/main.c
index bcc4f7a82649..0749afdc34b5 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -86,6 +86,12 @@ struct mod_tree_root mod_tree __cacheline_aligned = {
static unsigned long module_addr_min = -1UL, module_addr_max;
#endif /* CONFIG_MODULES_TREE_LOOKUP */

+struct symsearch {
+ const struct kernel_symbol *start, *stop;
+ const s32 *crcs;
+ enum mod_license license;
+};
+
/*
* Bounds of module text, for speeding up __module_address.
* Protected by module_mutex.
@@ -244,28 +250,6 @@ static __maybe_unused void *any_section_objs(const struct load_info *info,
#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
#endif

-struct symsearch {
- const struct kernel_symbol *start, *stop;
- const s32 *crcs;
- enum mod_license {
- NOT_GPL_ONLY,
- GPL_ONLY,
- } license;
-};
-
-struct find_symbol_arg {
- /* Input */
- const char *name;
- bool gplok;
- bool warn;
-
- /* Output */
- struct module *owner;
- const s32 *crc;
- const struct kernel_symbol *sym;
- enum mod_license license;
-};
-
static bool check_exported_symbol(const struct symsearch *syms,
struct module *owner,
unsigned int symnum, void *data)
@@ -327,7 +311,7 @@ static bool find_exported_symbol_in_section(const struct symsearch *syms,
* Find an exported symbol and return it, along with, (optional) crc and
* (optional) module which owns it. Needs preempt disabled or module_mutex.
*/
-static bool find_symbol(struct find_symbol_arg *fsa)
+bool find_symbol(struct find_symbol_arg *fsa)
{
static const struct symsearch arr[] = {
{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
@@ -1001,7 +985,7 @@ size_t modinfo_attrs_count = ARRAY_SIZE(modinfo_attrs);

static const char vermagic[] = VERMAGIC_STRING;

-static int try_to_force_load(struct module *mod, const char *reason)
+int try_to_force_load(struct module *mod, const char *reason)
{
#ifdef CONFIG_MODULE_FORCE_LOAD
if (!test_taint(TAINT_FORCED_MODULE))
@@ -1013,115 +997,6 @@ static int try_to_force_load(struct module *mod, const char *reason)
#endif
}

-#ifdef CONFIG_MODVERSIONS
-
-static u32 resolve_rel_crc(const s32 *crc)
-{
- return *(u32 *)((void *)crc + *crc);
-}
-
-static int check_version(const struct load_info *info,
- const char *symname,
- struct module *mod,
- const s32 *crc)
-{
- Elf_Shdr *sechdrs = info->sechdrs;
- unsigned int versindex = info->index.vers;
- unsigned int i, num_versions;
- struct modversion_info *versions;
-
- /* Exporting module didn't supply crcs? OK, we're already tainted. */
- if (!crc)
- return 1;
-
- /* No versions at all? modprobe --force does this. */
- if (versindex == 0)
- return try_to_force_load(mod, symname) == 0;
-
- versions = (void *) sechdrs[versindex].sh_addr;
- num_versions = sechdrs[versindex].sh_size
- / sizeof(struct modversion_info);
-
- for (i = 0; i < num_versions; i++) {
- u32 crcval;
-
- if (strcmp(versions[i].name, symname) != 0)
- continue;
-
- if (IS_ENABLED(CONFIG_MODULE_REL_CRCS))
- crcval = resolve_rel_crc(crc);
- else
- crcval = *crc;
- if (versions[i].crc == crcval)
- return 1;
- pr_debug("Found checksum %X vs module %lX\n",
- crcval, versions[i].crc);
- goto bad_version;
- }
-
- /* Broken toolchain. Warn once, then let it go.. */
- pr_warn_once("%s: no symbol version for %s\n", info->name, symname);
- return 1;
-
-bad_version:
- pr_warn("%s: disagrees about version of symbol %s\n",
- info->name, symname);
- return 0;
-}
-
-static inline int check_modstruct_version(const struct load_info *info,
- struct module *mod)
-{
- struct find_symbol_arg fsa = {
- .name = "module_layout",
- .gplok = true,
- };
-
- /*
- * Since this should be found in kernel (which can't be removed), no
- * locking is necessary -- use preempt_disable() to placate lockdep.
- */
- preempt_disable();
- if (!find_symbol(&fsa)) {
- preempt_enable();
- BUG();
- }
- preempt_enable();
- return check_version(info, "module_layout", mod, fsa.crc);
-}
-
-/* First part is kernel version, which we ignore if module has crcs. */
-static inline int same_magic(const char *amagic, const char *bmagic,
- bool has_crcs)
-{
- if (has_crcs) {
- amagic += strcspn(amagic, " ");
- bmagic += strcspn(bmagic, " ");
- }
- return strcmp(amagic, bmagic) == 0;
-}
-#else
-static inline int check_version(const struct load_info *info,
- const char *symname,
- struct module *mod,
- const s32 *crc)
-{
- return 1;
-}
-
-static inline int check_modstruct_version(const struct load_info *info,
- struct module *mod)
-{
- return 1;
-}
-
-static inline int same_magic(const char *amagic, const char *bmagic,
- bool has_crcs)
-{
- return strcmp(amagic, bmagic) == 0;
-}
-#endif /* CONFIG_MODVERSIONS */
-
static char *get_modinfo(const struct load_info *info, const char *tag);
static char *get_next_modinfo(const struct load_info *info, const char *tag,
char *prev);
@@ -3247,18 +3122,3 @@ void print_modules(void)
pr_cont(" [last unloaded: %s]", last_unloaded_module);
pr_cont("\n");
}
-
-#ifdef CONFIG_MODVERSIONS
-/*
- * Generate the signature for all relevant module structures here.
- * If these change, we don't want to try to parse the module.
- */
-void module_layout(struct module *mod,
- struct modversion_info *ver,
- struct kernel_param *kp,
- struct kernel_symbol *ks,
- struct tracepoint * const *tp)
-{
-}
-EXPORT_SYMBOL(module_layout);
-#endif
diff --git a/kernel/module/version.c b/kernel/module/version.c
new file mode 100644
index 000000000000..adaedce1dc97
--- /dev/null
+++ b/kernel/module/version.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Module version support
+ *
+ * Copyright (C) 2008 Rusty Russell
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/printk.h>
+#include "internal.h"
+
+static u32 resolve_rel_crc(const s32 *crc)
+{
+ return *(u32 *)((void *)crc + *crc);
+}
+
+int check_version(const struct load_info *info,
+ const char *symname,
+ struct module *mod,
+ const s32 *crc)
+{
+ Elf_Shdr *sechdrs = info->sechdrs;
+ unsigned int versindex = info->index.vers;
+ unsigned int i, num_versions;
+ struct modversion_info *versions;
+
+ /* Exporting module didn't supply crcs? OK, we're already tainted. */
+ if (!crc)
+ return 1;
+
+ /* No versions at all? modprobe --force does this. */
+ if (versindex == 0)
+ return try_to_force_load(mod, symname) == 0;
+
+ versions = (void *)sechdrs[versindex].sh_addr;
+ num_versions = sechdrs[versindex].sh_size
+ / sizeof(struct modversion_info);
+
+ for (i = 0; i < num_versions; i++) {
+ u32 crcval;
+
+ if (strcmp(versions[i].name, symname) != 0)
+ continue;
+
+ if (IS_ENABLED(CONFIG_MODULE_REL_CRCS))
+ crcval = resolve_rel_crc(crc);
+ else
+ crcval = *crc;
+ if (versions[i].crc == crcval)
+ return 1;
+ pr_debug("Found checksum %X vs module %lX\n",
+ crcval, versions[i].crc);
+ goto bad_version;
+ }
+
+ /* Broken toolchain. Warn once, then let it go.. */
+ pr_warn_once("%s: no symbol version for %s\n", info->name, symname);
+ return 1;
+
+bad_version:
+ pr_warn("%s: disagrees about version of symbol %s\n", info->name, symname);
+ return 0;
+}
+
+int check_modstruct_version(const struct load_info *info,
+ struct module *mod)
+{
+ struct find_symbol_arg fsa = {
+ .name = "module_layout",
+ .gplok = true,
+ };
+
+ /*
+ * Since this should be found in kernel (which can't be removed), no
+ * locking is necessary -- use preempt_disable() to placate lockdep.
+ */
+ preempt_disable();
+ if (!find_symbol(&fsa)) {
+ preempt_enable();
+ BUG();
+ }
+ preempt_enable();
+ return check_version(info, "module_layout", mod, fsa.crc);
+}
+
+/* First part is kernel version, which we ignore if module has crcs. */
+int same_magic(const char *amagic, const char *bmagic,
+ bool has_crcs)
+{
+ if (has_crcs) {
+ amagic += strcspn(amagic, " ");
+ bmagic += strcspn(bmagic, " ");
+ }
+ return strcmp(amagic, bmagic) == 0;
+}
+
+/*
+ * Generate the signature for all relevant module structures here.
+ * If these change, we don't want to try to parse the module.
+ */
+void module_layout(struct module *mod,
+ struct modversion_info *ver,
+ struct kernel_param *kp,
+ struct kernel_symbol *ks,
+ struct tracepoint * const *tp)
+{
+}
+EXPORT_SYMBOL(module_layout);
--
2.34.1

2022-02-20 07:27:07

by Aaron Tomlin

[permalink] [raw]
Subject: [PATCH v6 12/13] module: Move kdb_modules list out of core code

No functional change.

This patch migrates kdb_modules list to core kdb code
since the list of added/or loaded modules is no longer
private.

Signed-off-by: Aaron Tomlin <[email protected]>
---
kernel/debug/kdb/kdb_main.c | 5 +++++
kernel/debug/kdb/kdb_private.h | 4 ----
kernel/module/main.c | 4 ----
3 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 0852a537dad4..5369bf45c5d4 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -59,6 +59,11 @@ EXPORT_SYMBOL(kdb_grepping_flag);
int kdb_grep_leading;
int kdb_grep_trailing;

+#ifdef CONFIG_MODULES
+extern struct list_head modules;
+static struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
+#endif /* CONFIG_MODULES */
+
/*
* Kernel debugger state flags
*/
diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h
index 0d2f9feea0a4..1f8c519a5f81 100644
--- a/kernel/debug/kdb/kdb_private.h
+++ b/kernel/debug/kdb/kdb_private.h
@@ -226,10 +226,6 @@ extern void kdb_kbd_cleanup_state(void);
#define kdb_kbd_cleanup_state()
#endif /* ! CONFIG_KDB_KEYBOARD */

-#ifdef CONFIG_MODULES
-extern struct list_head *kdb_modules;
-#endif /* CONFIG_MODULES */
-
extern char kdb_prompt_str[];

#define KDB_WORD_SIZE ((int)sizeof(unsigned long))
diff --git a/kernel/module/main.c b/kernel/module/main.c
index b8a59b5c3e3a..bcc4f7a82649 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -108,10 +108,6 @@ static void mod_update_bounds(struct module *mod)
__mod_update_bounds(mod->init_layout.base, mod->init_layout.size);
}

-#ifdef CONFIG_KGDB_KDB
-struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
-#endif /* CONFIG_KGDB_KDB */
-
static void module_assert_mutex_or_preempt(void)
{
#ifdef CONFIG_LOCKDEP
--
2.34.1

2022-02-22 15:02:05

by Miroslav Benes

[permalink] [raw]
Subject: Re: [PATCH v6 11/13] module: Move sysfs support into a separate file

On Fri, 18 Feb 2022, Aaron Tomlin wrote:

> No functional change.
>
> This patch migrates module sysfs support out of core code into
> kernel/module/sysfs.c. In addition simple code refactoring to
> make this possible.
>
> Signed-off-by: Aaron Tomlin <[email protected]>

There was apparently a problem on your side when sending the series. There
is Reply-To field which probably should have been In-Reply-To. It also
applied to the following two patches.

> kernel/module/Makefile | 1 +
> kernel/module/internal.h | 21 ++
> kernel/module/main.c | 469 +--------------------------------------
> kernel/module/sysfs.c | 436 ++++++++++++++++++++++++++++++++++++
> 4 files changed, 461 insertions(+), 466 deletions(-)
> create mode 100644 kernel/module/sysfs.c
>
> diff --git a/kernel/module/Makefile b/kernel/module/Makefile
> index f66fda0b41cc..a3cbe09ce2b2 100644
> --- a/kernel/module/Makefile
> +++ b/kernel/module/Makefile
> @@ -14,4 +14,5 @@ obj-$(CONFIG_STRICT_MODULE_RWX) += strict_rwx.o
> obj-$(CONFIG_DEBUG_KMEMLEAK) += debug_kmemleak.o
> obj-$(CONFIG_KALLSYMS) += kallsyms.o
> obj-$(CONFIG_PROC_FS) += procfs.o
> +obj-$(CONFIG_SYSFS) += sysfs.o
> endif
> diff --git a/kernel/module/internal.h b/kernel/module/internal.h
> index ddb37024a0d6..74096cca742c 100644
> --- a/kernel/module/internal.h
> +++ b/kernel/module/internal.h
> @@ -34,6 +34,9 @@
> extern struct mutex module_mutex;
> extern struct list_head modules;
>
> +extern struct module_attribute *modinfo_attrs[];
> +extern size_t modinfo_attrs_count;
> +
> /* Provided by the linker */
> extern const struct kernel_symbol __start___ksymtab[];
> extern const struct kernel_symbol __stop___ksymtab[];
> @@ -213,3 +216,21 @@ static inline bool sect_empty(const Elf_Shdr *sect)
> static inline void layout_symtab(struct module *mod, struct load_info *info) { }
> static inline void add_kallsyms(struct module *mod, const struct load_info *info) { }
> #endif /* CONFIG_KALLSYMS */
> +
> +#ifdef CONFIG_SYSFS
> +int mod_sysfs_setup(struct module *mod, const struct load_info *info,
> + struct kernel_param *kparam, unsigned int num_params);
> +void mod_sysfs_teardown(struct module *mod);
> +void init_param_lock(struct module *mod);
> +#else /* !CONFIG_SYSFS */
> +static inline int mod_sysfs_setup(struct module *mod,
> + const struct load_info *info,
> + struct kernel_param *kparam,
> + unsigned int num_params)

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Miroslav