[RFC PATCH v3 00/13] module: core code clean up

[RFC PATCH v3 00/13] module: core code clean up

[Aaron Tomlin]

Hi Luis,

[Note: Cc'd live-patching for feedback on livepatch specific changes]

Firstly, apologies for the delay.

As per your suggestion [1], this is an attempt to refactor and split
optional code out of core module support code into separate components.
This version is based on branch mcgrof/modules-next since a97ac8cb24a3/or
modules-5.17-rc1. Please let me know your thoughts.

Changes since v1 [2]:

  - Moved module version support code into a new file

Changes since v2 [3]:

 - Move module decompress support to a separate file
 - Make check_modinfo_livepatch() generic (Petr Mladek)
 - Remove filename from each newly created file (Luis Chamberlain)
 - Addressed some (i.e. --ignore=ASSIGN_IN_IF,AVOID_BUG was used)
   minor scripts/checkpatch.pl concerns e.g., use strscpy over
   strlcpy and missing a blank line after declarations (Allen)

[1]: https://lore.kernel.org/lkml/YbEZ4HgSYQEPuRmS@bombadil.infradead.org/
[2]: https://lore.kernel.org/lkml/20211228213041.1356334-1-atomlin@redhat.com/
[3]: https://lore.kernel.org/lkml/20220106234319.2067842-1-atomlin@redhat.com/


Aaron Tomlin (13):
  module: Move all into module/
  module: Simple refactor in preparation for split
  module: Move livepatch support to a separate file
  module: Move latched RB-tree support to a separate file
  module: Move arch strict rwx support to a separate file
  module: Move strict rwx support to a separate file
  module: Move extra signature support out of core code
  module: Move kmemleak support to a separate file
  module: Move kallsyms support into a separate file
  module: Move procfs support into a separate file
  module: Move sysfs support into a separate file
  module: Move kdb_modules list out of core code
  module: Move version support into a separate file

 MAINTAINERS                                   |    2 +-
 include/linux/module.h                        |   92 +-
 kernel/Makefile                               |    5 +-
 kernel/debug/kdb/kdb_main.c                   |    5 +
 kernel/module-internal.h                      |   50 -
 kernel/module/Makefile                        |   18 +
 kernel/module/arch_strict_rwx.c               |   44 +
 kernel/module/debug_kmemleak.c                |   30 +
 .../decompress.c}                             |    2 +-
 kernel/module/internal.h                      |  202 ++
 kernel/module/kallsyms.c                      |  502 +++++
 kernel/module/livepatch.c                     |   74 +
 kernel/{module.c => module/main.c}            | 1879 +----------------
 kernel/module/procfs.c                        |  142 ++
 .../signature.c}                              |    0
 kernel/module/signing.c                       |  120 ++
 kernel/module/strict_rwx.c                    |   83 +
 kernel/module/sysfs.c                         |  425 ++++
 kernel/module/tree_lookup.c                   |  108 +
 kernel/module/version.c                       |  110 +
 kernel/module_signing.c                       |   45 -
 21 files changed, 2032 insertions(+), 1906 deletions(-)
 delete mode 100644 kernel/module-internal.h
 create mode 100644 kernel/module/Makefile
 create mode 100644 kernel/module/arch_strict_rwx.c
 create mode 100644 kernel/module/debug_kmemleak.c
 rename kernel/{module_decompress.c => module/decompress.c} (99%)
 create mode 100644 kernel/module/internal.h
 create mode 100644 kernel/module/kallsyms.c
 create mode 100644 kernel/module/livepatch.c
 rename kernel/{module.c => module/main.c} (63%)
 create mode 100644 kernel/module/procfs.c
 rename kernel/{module_signature.c => module/signature.c} (100%)
 create mode 100644 kernel/module/signing.c
 create mode 100644 kernel/module/strict_rwx.c
 create mode 100644 kernel/module/sysfs.c
 create mode 100644 kernel/module/tree_lookup.c
 create mode 100644 kernel/module/version.c
 delete mode 100644 kernel/module_signing.c


base-commit: a97ac8cb24a3c3ad74794adb83717ef1605d1b47
-- 
2.34.1

[RFC PATCH v3 01/13] module: Move all into module/

[Aaron Tomlin]

No functional changes.

This patch moves all module related code into a separate directory,
modifies each file name and creates a new Makefile. Note: this effort
is in preparation to refactor core module code.

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
 MAINTAINERS                                         | 2 +-
 kernel/Makefile                                     | 5 +----
 kernel/module/Makefile                              | 9 +++++++++
 kernel/{module_decompress.c => module/decompress.c} | 2 +-
 kernel/{module-internal.h => module/internal.h}     | 0
 kernel/{module.c => module/main.c}                  | 2 +-
 kernel/{module_signature.c => module/signature.c}   | 0
 kernel/{module_signing.c => module/signing.c}       | 2 +-
 8 files changed, 14 insertions(+), 8 deletions(-)
 create mode 100644 kernel/module/Makefile
 rename kernel/{module_decompress.c => module/decompress.c} (99%)
 rename kernel/{module-internal.h => module/internal.h} (100%)
 rename kernel/{module.c => module/main.c} (99%)
 rename kernel/{module_signature.c => module/signature.c} (100%)
 rename kernel/{module_signing.c => module/signing.c} (97%)

diff --git a/MAINTAINERS b/MAINTAINERS
index acd112c42255..a98f4700acb7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -12976,7 +12976,7 @@ L:	linux-kernel@vger.kernel.org
 S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux.git modules-next
 F:	include/linux/module.h
-F:	kernel/module.c
+F:	kernel/module/main.c
 
 MONOLITHIC POWER SYSTEM PMIC DRIVER
 M:	Saravanan Sekar <sravanhome@gmail.com>
diff --git a/kernel/Makefile b/kernel/Makefile
index 56f4ee97f328..3a6380975c57 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -53,6 +53,7 @@ obj-y += rcu/
 obj-y += livepatch/
 obj-y += dma/
 obj-y += entry/
+obj-y += module/
 
 obj-$(CONFIG_KCMP) += kcmp.o
 obj-$(CONFIG_FREEZER) += freezer.o
@@ -66,10 +67,6 @@ ifneq ($(CONFIG_SMP),y)
 obj-y += up.o
 endif
 obj-$(CONFIG_UID16) += uid16.o
-obj-$(CONFIG_MODULES) += module.o
-obj-$(CONFIG_MODULE_DECOMPRESS) += module_decompress.o
-obj-$(CONFIG_MODULE_SIG) += module_signing.o
-obj-$(CONFIG_MODULE_SIG_FORMAT) += module_signature.o
 obj-$(CONFIG_KALLSYMS) += kallsyms.o
 obj-$(CONFIG_BSD_PROCESS_ACCT) += acct.o
 obj-$(CONFIG_CRASH_CORE) += crash_core.o
diff --git a/kernel/module/Makefile b/kernel/module/Makefile
new file mode 100644
index 000000000000..2902fc7d0ef1
--- /dev/null
+++ b/kernel/module/Makefile
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for linux kernel module support
+#
+
+obj-$(CONFIG_MODULES) += main.o
+obj-$(CONFIG_MODULE_DECOMPRESS) += decompress.o
+obj-$(CONFIG_MODULE_SIG) += signing.o
+obj-$(CONFIG_MODULE_SIG_FORMAT) += signature.o
diff --git a/kernel/module_decompress.c b/kernel/module/decompress.c
similarity index 99%
rename from kernel/module_decompress.c
rename to kernel/module/decompress.c
index b01c69c2ff99..c153fd8a4444 100644
--- a/kernel/module_decompress.c
+++ b/kernel/module/decompress.c
@@ -12,7 +12,7 @@
 #include <linux/sysfs.h>
 #include <linux/vmalloc.h>
 
-#include "module-internal.h"
+#include "internal.h"
 
 static int module_extend_max_pages(struct load_info *info, unsigned int extent)
 {
diff --git a/kernel/module-internal.h b/kernel/module/internal.h
similarity index 100%
rename from kernel/module-internal.h
rename to kernel/module/internal.h
diff --git a/kernel/module.c b/kernel/module/main.c
similarity index 99%
rename from kernel/module.c
rename to kernel/module/main.c
index 387ee77bdbd6..d8c6269af6cf 100644
--- a/kernel/module.c
+++ b/kernel/module/main.c
@@ -58,7 +58,7 @@
 #include <linux/dynamic_debug.h>
 #include <linux/audit.h>
 #include <uapi/linux/module.h>
-#include "module-internal.h"
+#include "internal.h"
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/module.h>
diff --git a/kernel/module_signature.c b/kernel/module/signature.c
similarity index 100%
rename from kernel/module_signature.c
rename to kernel/module/signature.c
diff --git a/kernel/module_signing.c b/kernel/module/signing.c
similarity index 97%
rename from kernel/module_signing.c
rename to kernel/module/signing.c
index 8723ae70ea1f..8aeb6d2ee94b 100644
--- a/kernel/module_signing.c
+++ b/kernel/module/signing.c
@@ -12,7 +12,7 @@
 #include <linux/string.h>
 #include <linux/verification.h>
 #include <crypto/public_key.h>
-#include "module-internal.h"
+#include "internal.h"
 
 /*
  * Verify the signature on a module.
-- 
2.34.1

[RFC PATCH v3 02/13] module: Simple refactor in preparation for split

[Aaron Tomlin]

No functional change.

This patch makes it possible to move non-essential code
out of core module code.

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
 kernel/module/internal.h | 22 ++++++++++++++++++++++
 kernel/module/main.c     | 23 ++---------------------
 2 files changed, 24 insertions(+), 21 deletions(-)

diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index 8c381c99062f..e3c593f8767f 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -7,6 +7,28 @@
 
 #include <linux/elf.h>
 #include <asm/module.h>
+#include <linux/mutex.h>
+
+#ifndef ARCH_SHF_SMALL
+#define ARCH_SHF_SMALL 0
+#endif
+
+/* If this is set, the section belongs in the init part of the module */
+#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
+/* Maximum number of characters written by module_flags() */
+#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
+#define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4))
+
+extern struct mutex module_mutex;
+extern struct list_head modules;
+
+/* Provided by the linker */
+extern const struct kernel_symbol __start___ksymtab[];
+extern const struct kernel_symbol __stop___ksymtab[];
+extern const struct kernel_symbol __start___ksymtab_gpl[];
+extern const struct kernel_symbol __stop___ksymtab_gpl[];
+extern const s32 __start___kcrctab[];
+extern const s32 __start___kcrctab_gpl[];
 
 struct load_info {
 	const char *name;
diff --git a/kernel/module/main.c b/kernel/module/main.c
index d8c6269af6cf..fee64c4957f3 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -63,10 +63,6 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/module.h>
 
-#ifndef ARCH_SHF_SMALL
-#define ARCH_SHF_SMALL 0
-#endif
-
 /*
  * Modules' sections will be aligned on page boundaries
  * to ensure complete separation of code and data, but
@@ -78,9 +74,6 @@
 # define debug_align(X) (X)
 #endif
 
-/* If this is set, the section belongs in the init part of the module */
-#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
-
 /*
  * Mutex protects:
  * 1) List of modules (also safely readable with preempt_disable),
@@ -88,8 +81,8 @@
  * 3) module_addr_min/module_addr_max.
  * (delete and add uses RCU list operations).
  */
-static DEFINE_MUTEX(module_mutex);
-static LIST_HEAD(modules);
+DEFINE_MUTEX(module_mutex);
+LIST_HEAD(modules);
 
 /* Work queue for freeing init sections in success case */
 static void do_free_init(struct work_struct *w);
@@ -408,14 +401,6 @@ static __maybe_unused void *any_section_objs(const struct load_info *info,
 	return (void *)info->sechdrs[sec].sh_addr;
 }
 
-/* Provided by the linker */
-extern const struct kernel_symbol __start___ksymtab[];
-extern const struct kernel_symbol __stop___ksymtab[];
-extern const struct kernel_symbol __start___ksymtab_gpl[];
-extern const struct kernel_symbol __stop___ksymtab_gpl[];
-extern const s32 __start___kcrctab[];
-extern const s32 __start___kcrctab_gpl[];
-
 #ifndef CONFIG_MODVERSIONS
 #define symversion(base, idx) NULL
 #else
@@ -1490,7 +1475,6 @@ struct module_sect_attrs {
 	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)
@@ -4555,9 +4539,6 @@ static void cfi_cleanup(struct module *mod)
 #endif
 }
 
-/* Maximum number of characters written by module_flags() */
-#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
-
 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
 static char *module_flags(struct module *mod, char *buf)
 {
-- 
2.34.1

[RFC PATCH v3 03/13] module: Move livepatch support to a separate file

[Aaron Tomlin]

No functional change.

This patch migrates livepatch support (i.e. used during module
add/or load and remove/or deletion) from core module code into
kernel/module/livepatch.c. At the moment it contains code to
persist Elf information about a given livepatch module, only.

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
 include/linux/module.h    |  11 ++++
 kernel/module/Makefile    |   1 +
 kernel/module/internal.h  |  10 ++++
 kernel/module/livepatch.c |  74 +++++++++++++++++++++++++++
 kernel/module/main.c      | 102 ++++----------------------------------
 5 files changed, 106 insertions(+), 92 deletions(-)
 create mode 100644 kernel/module/livepatch.c

diff --git a/include/linux/module.h b/include/linux/module.h
index f4338235ed2c..8d49f12a7601 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -668,11 +668,22 @@ static inline bool is_livepatch_module(struct module *mod)
 {
 	return mod->klp;
 }
+
+static inline bool set_livepatch_module(struct module *mod)
+{
+	mod->klp = true;
+	return true;
+}
 #else /* !CONFIG_LIVEPATCH */
 static inline bool is_livepatch_module(struct module *mod)
 {
 	return false;
 }
+
+static inline bool set_livepatch_module(struct module *mod)
+{
+	return false;
+}
 #endif /* CONFIG_LIVEPATCH */
 
 bool is_module_sig_enforced(void);
diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index 2902fc7d0ef1..ba3ebdb7055b 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_MODULES) += main.o
 obj-$(CONFIG_MODULE_DECOMPRESS) += decompress.o
 obj-$(CONFIG_MODULE_SIG) += signing.o
 obj-$(CONFIG_MODULE_SIG_FORMAT) += signature.o
+obj-$(CONFIG_LIVEPATCH) += livepatch.o
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index e3c593f8767f..0cd624179545 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -57,6 +57,16 @@ struct load_info {
 
 extern int mod_verify_sig(const void *mod, struct load_info *info);
 
+#ifdef CONFIG_LIVEPATCH
+extern int copy_module_elf(struct module *mod, struct load_info *info);
+extern void free_module_elf(struct module *mod);
+#else /* !CONFIG_LIVEPATCH */
+static inline int copy_module_elf(struct module *mod, struct load_info *info)
+{
+	return 0;
+}
+static inline void free_module_elf(struct module *mod) { }
+#endif /* CONFIG_LIVEPATCH */
 #ifdef CONFIG_MODULE_DECOMPRESS
 int module_decompress(struct load_info *info, const void *buf, size_t size);
 void module_decompress_cleanup(struct load_info *info);
diff --git a/kernel/module/livepatch.c b/kernel/module/livepatch.c
new file mode 100644
index 000000000000..961045d32332
--- /dev/null
+++ b/kernel/module/livepatch.c
@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Module livepatch support
+ *
+ * Copyright (C) 2016 Jessica Yu <jeyu@redhat.com>
+ */
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include "internal.h"
+
+/*
+ * Persist Elf information about a module. Copy the Elf header,
+ * section header table, section string table, and symtab section
+ * index from info to mod->klp_info.
+ */
+int copy_module_elf(struct module *mod, struct load_info *info)
+{
+	unsigned int size, symndx;
+	int ret;
+
+	size = sizeof(*mod->klp_info);
+	mod->klp_info = kmalloc(size, GFP_KERNEL);
+	if (mod->klp_info == NULL)
+		return -ENOMEM;
+
+	/* Elf header */
+	size = sizeof(mod->klp_info->hdr);
+	memcpy(&mod->klp_info->hdr, info->hdr, size);
+
+	/* Elf section header table */
+	size = sizeof(*info->sechdrs) * info->hdr->e_shnum;
+	mod->klp_info->sechdrs = kmemdup(info->sechdrs, size, GFP_KERNEL);
+	if (mod->klp_info->sechdrs == NULL) {
+		ret = -ENOMEM;
+		goto free_info;
+	}
+
+	/* Elf section name string table */
+	size = info->sechdrs[info->hdr->e_shstrndx].sh_size;
+	mod->klp_info->secstrings = kmemdup(info->secstrings, size, GFP_KERNEL);
+	if (mod->klp_info->secstrings == NULL) {
+		ret = -ENOMEM;
+		goto free_sechdrs;
+	}
+
+	/* Elf symbol section index */
+	symndx = info->index.sym;
+	mod->klp_info->symndx = symndx;
+
+	/*
+	 * For livepatch modules, core_kallsyms.symtab is a complete
+	 * copy of the original symbol table. Adjust sh_addr to point
+	 * to core_kallsyms.symtab since the copy of the symtab in module
+	 * init memory is freed at the end of do_init_module().
+	 */
+	mod->klp_info->sechdrs[symndx].sh_addr = (unsigned long) mod->core_kallsyms.symtab;
+
+	return 0;
+
+free_sechdrs:
+	kfree(mod->klp_info->sechdrs);
+free_info:
+	kfree(mod->klp_info);
+	return ret;
+}
+
+void free_module_elf(struct module *mod)
+{
+	kfree(mod->klp_info->sechdrs);
+	kfree(mod->klp_info->secstrings);
+	kfree(mod->klp_info);
+}
diff --git a/kernel/module/main.c b/kernel/module/main.c
index fee64c4957f3..c91c7e57bca7 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -2042,81 +2042,6 @@ static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
 }
 #endif /*  CONFIG_STRICT_MODULE_RWX */
 
-#ifdef CONFIG_LIVEPATCH
-/*
- * Persist Elf information about a module. Copy the Elf header,
- * section header table, section string table, and symtab section
- * index from info to mod->klp_info.
- */
-static int copy_module_elf(struct module *mod, struct load_info *info)
-{
-	unsigned int size, symndx;
-	int ret;
-
-	size = sizeof(*mod->klp_info);
-	mod->klp_info = kmalloc(size, GFP_KERNEL);
-	if (mod->klp_info == NULL)
-		return -ENOMEM;
-
-	/* Elf header */
-	size = sizeof(mod->klp_info->hdr);
-	memcpy(&mod->klp_info->hdr, info->hdr, size);
-
-	/* Elf section header table */
-	size = sizeof(*info->sechdrs) * info->hdr->e_shnum;
-	mod->klp_info->sechdrs = kmemdup(info->sechdrs, size, GFP_KERNEL);
-	if (mod->klp_info->sechdrs == NULL) {
-		ret = -ENOMEM;
-		goto free_info;
-	}
-
-	/* Elf section name string table */
-	size = info->sechdrs[info->hdr->e_shstrndx].sh_size;
-	mod->klp_info->secstrings = kmemdup(info->secstrings, size, GFP_KERNEL);
-	if (mod->klp_info->secstrings == NULL) {
-		ret = -ENOMEM;
-		goto free_sechdrs;
-	}
-
-	/* Elf symbol section index */
-	symndx = info->index.sym;
-	mod->klp_info->symndx = symndx;
-
-	/*
-	 * For livepatch modules, core_kallsyms.symtab is a complete
-	 * copy of the original symbol table. Adjust sh_addr to point
-	 * to core_kallsyms.symtab since the copy of the symtab in module
-	 * init memory is freed at the end of do_init_module().
-	 */
-	mod->klp_info->sechdrs[symndx].sh_addr = \
-		(unsigned long) mod->core_kallsyms.symtab;
-
-	return 0;
-
-free_sechdrs:
-	kfree(mod->klp_info->sechdrs);
-free_info:
-	kfree(mod->klp_info);
-	return ret;
-}
-
-static void free_module_elf(struct module *mod)
-{
-	kfree(mod->klp_info->sechdrs);
-	kfree(mod->klp_info->secstrings);
-	kfree(mod->klp_info);
-}
-#else /* !CONFIG_LIVEPATCH */
-static int copy_module_elf(struct module *mod, struct load_info *info)
-{
-	return 0;
-}
-
-static void free_module_elf(struct module *mod)
-{
-}
-#endif /* CONFIG_LIVEPATCH */
-
 void __weak module_memfree(void *module_region)
 {
 	/*
@@ -3091,30 +3016,23 @@ static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned l
 	return 0;
 }
 
-#ifdef CONFIG_LIVEPATCH
 static int check_modinfo_livepatch(struct module *mod, struct load_info *info)
 {
-	if (get_modinfo(info, "livepatch")) {
-		mod->klp = true;
+	if (!get_modinfo(info, "livepatch"))
+		/* Nothing more to do */
+		return 0;
+
+	if (set_livepatch_module(mod)) {
 		add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK);
 		pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
-			       mod->name);
-	}
-
-	return 0;
-}
-#else /* !CONFIG_LIVEPATCH */
-static int check_modinfo_livepatch(struct module *mod, struct load_info *info)
-{
-	if (get_modinfo(info, "livepatch")) {
-		pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
-		       mod->name);
-		return -ENOEXEC;
+				mod->name);
+		return 0;
 	}
 
-	return 0;
+	pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
+		mod->name);
+	return -ENOEXEC;
 }
-#endif /* CONFIG_LIVEPATCH */
 
 static void check_modinfo_retpoline(struct module *mod, struct load_info *info)
 {
-- 
2.34.1

Re: [RFC PATCH v3 03/13] module: Move livepatch support to a separate file

[Joe Perches]

On Fri, 2022-01-28 at 20:39 +0000, Aaron Tomlin wrote:
> No functional change.
> 
> This patch migrates livepatch support (i.e. used during module
> add/or load and remove/or deletion) from core module code into
> kernel/module/livepatch.c. At the moment it contains code to
> persist Elf information about a given livepatch module, only.
[]
> diff --git a/include/linux/module.h b/include/linux/module.h
[]
> @@ -668,11 +668,22 @@ static inline bool is_livepatch_module(struct module *mod)
>  {
>  	return mod->klp;
>  }
> +
> +static inline bool set_livepatch_module(struct module *mod)
> +{
> +	mod->klp = true;
> +	return true;
> +}
>  #else /* !CONFIG_LIVEPATCH */
>  static inline bool is_livepatch_module(struct module *mod)
>  {
>  	return false;
>  }
> +
> +static inline bool set_livepatch_module(struct module *mod)
> +{
> +	return false;
> +}
>  #endif /* CONFIG_LIVEPATCH */

style trivia:

Generally, these static inlines can be written deduplicating
the function declaration and using IS_ENABLED or #if inside
the definition.

Something like:

static inline bool is_livepatch_module(struct module *mod)
{
	if (IS_ENABLED(CONFIG_LIVEPATCH)) {
		mod->klp = true;
		return true;
	}
	return false;
}

or

static inline bool is_livepatch_module(struct module *mod)
{
#ifdef CONFIG_LIVEPATCH
	mod->klp = true;
	return true;
#else
	return false;
#endif
}

[RFC PATCH v3 04/13] module: Move latched RB-tree support to a separate file

[Aaron Tomlin]

No functional change.

This patch migrates module latched RB-tree support
(e.g. see __module_address()) from core module code
into kernel/module/tree_lookup.c.

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
 include/linux/module.h      |  37 +++++++++-
 kernel/module/Makefile      |   1 +
 kernel/module/main.c        | 134 ------------------------------------
 kernel/module/tree_lookup.c | 108 +++++++++++++++++++++++++++++
 4 files changed, 144 insertions(+), 136 deletions(-)
 create mode 100644 kernel/module/tree_lookup.c

diff --git a/include/linux/module.h b/include/linux/module.h
index 8d49f12a7601..377bdb9952cf 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -340,11 +340,44 @@ struct module_layout {
 };
 
 #ifdef CONFIG_MODULES_TREE_LOOKUP
+struct mod_tree_root {
+	struct latch_tree_root root;
+	unsigned long addr_min;
+	unsigned long addr_max;
+} mod_tree __cacheline_aligned = {
+	.addr_min = -1UL,
+};
+
+#define module_addr_min mod_tree.addr_min
+#define module_addr_max mod_tree.addr_max
+
+extern void mod_tree_insert(struct module *mod);
+extern void mod_tree_remove_init(struct module *mod);
+extern void mod_tree_remove(struct module *mod);
+extern struct module *mod_find(unsigned long addr);
 /* Only touch one cacheline for common rbtree-for-core-layout case. */
 #define __module_layout_align ____cacheline_aligned
-#else
+#else /* !CONFIG_MODULES_TREE_LOOKUP */
+
+static unsigned long module_addr_min = -1UL, module_addr_max;
+
+static void mod_tree_insert(struct module *mod) { }
+static void mod_tree_remove_init(struct module *mod) { }
+static void mod_tree_remove(struct module *mod) { }
+static struct module *mod_find(unsigned long addr)
+{
+	struct module *mod;
+
+	list_for_each_entry_rcu(mod, &modules, list,
+				lockdep_is_held(&module_mutex)) {
+		if (within_module(addr, mod))
+			return mod;
+	}
+
+	return NULL;
+}
 #define __module_layout_align
-#endif
+#endif /* CONFIG_MODULES_TREE_LOOKUP */
 
 struct mod_kallsyms {
 	Elf_Sym *symtab;
diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index ba3ebdb7055b..5990d2e4566d 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -8,3 +8,4 @@ obj-$(CONFIG_MODULE_DECOMPRESS) += decompress.o
 obj-$(CONFIG_MODULE_SIG) += signing.o
 obj-$(CONFIG_MODULE_SIG_FORMAT) += signature.o
 obj-$(CONFIG_LIVEPATCH) += livepatch.o
+obj-$(CONFIG_MODULES_TREE_LOOKUP) += tree_lookup.o
diff --git a/kernel/module/main.c b/kernel/module/main.c
index c91c7e57bca7..5c7c3201b5b4 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -89,140 +89,6 @@ static void do_free_init(struct work_struct *w);
 static DECLARE_WORK(init_free_wq, do_free_init);
 static LLIST_HEAD(init_free_list);
 
-#ifdef CONFIG_MODULES_TREE_LOOKUP
-
-/*
- * Use a latched RB-tree for __module_address(); this allows us to use
- * RCU-sched lookups of the address from any context.
- *
- * This is conditional on PERF_EVENTS || TRACING because those can really hit
- * __module_address() hard by doing a lot of stack unwinding; potentially from
- * NMI context.
- */
-
-static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
-{
-	struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
-
-	return (unsigned long)layout->base;
-}
-
-static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
-{
-	struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
-
-	return (unsigned long)layout->size;
-}
-
-static __always_inline bool
-mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b)
-{
-	return __mod_tree_val(a) < __mod_tree_val(b);
-}
-
-static __always_inline int
-mod_tree_comp(void *key, struct latch_tree_node *n)
-{
-	unsigned long val = (unsigned long)key;
-	unsigned long start, end;
-
-	start = __mod_tree_val(n);
-	if (val < start)
-		return -1;
-
-	end = start + __mod_tree_size(n);
-	if (val >= end)
-		return 1;
-
-	return 0;
-}
-
-static const struct latch_tree_ops mod_tree_ops = {
-	.less = mod_tree_less,
-	.comp = mod_tree_comp,
-};
-
-static struct mod_tree_root {
-	struct latch_tree_root root;
-	unsigned long addr_min;
-	unsigned long addr_max;
-} mod_tree __cacheline_aligned = {
-	.addr_min = -1UL,
-};
-
-#define module_addr_min mod_tree.addr_min
-#define module_addr_max mod_tree.addr_max
-
-static noinline void __mod_tree_insert(struct mod_tree_node *node)
-{
-	latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops);
-}
-
-static void __mod_tree_remove(struct mod_tree_node *node)
-{
-	latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops);
-}
-
-/*
- * These modifications: insert, remove_init and remove; are serialized by the
- * module_mutex.
- */
-static void mod_tree_insert(struct module *mod)
-{
-	mod->core_layout.mtn.mod = mod;
-	mod->init_layout.mtn.mod = mod;
-
-	__mod_tree_insert(&mod->core_layout.mtn);
-	if (mod->init_layout.size)
-		__mod_tree_insert(&mod->init_layout.mtn);
-}
-
-static void mod_tree_remove_init(struct module *mod)
-{
-	if (mod->init_layout.size)
-		__mod_tree_remove(&mod->init_layout.mtn);
-}
-
-static void mod_tree_remove(struct module *mod)
-{
-	__mod_tree_remove(&mod->core_layout.mtn);
-	mod_tree_remove_init(mod);
-}
-
-static struct module *mod_find(unsigned long addr)
-{
-	struct latch_tree_node *ltn;
-
-	ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops);
-	if (!ltn)
-		return NULL;
-
-	return container_of(ltn, struct mod_tree_node, node)->mod;
-}
-
-#else /* MODULES_TREE_LOOKUP */
-
-static unsigned long module_addr_min = -1UL, module_addr_max = 0;
-
-static void mod_tree_insert(struct module *mod) { }
-static void mod_tree_remove_init(struct module *mod) { }
-static void mod_tree_remove(struct module *mod) { }
-
-static struct module *mod_find(unsigned long addr)
-{
-	struct module *mod;
-
-	list_for_each_entry_rcu(mod, &modules, list,
-				lockdep_is_held(&module_mutex)) {
-		if (within_module(addr, mod))
-			return mod;
-	}
-
-	return NULL;
-}
-
-#endif /* MODULES_TREE_LOOKUP */
-
 /*
  * Bounds of module text, for speeding up __module_address.
  * Protected by module_mutex.
diff --git a/kernel/module/tree_lookup.c b/kernel/module/tree_lookup.c
new file mode 100644
index 000000000000..5f6d6de2dc60
--- /dev/null
+++ b/kernel/module/tree_lookup.c
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Modules tree lookup
+ *
+ * Copyright (C) 2015 Peter Zijlstra
+ * Copyright (C) 2015 Rusty Russell
+ */
+
+#include <linux/module.h>
+#include <linux/rbtree_latch.h>
+
+/*
+ * Use a latched RB-tree for __module_address(); this allows us to use
+ * RCU-sched lookups of the address from any context.
+ *
+ * This is conditional on PERF_EVENTS || TRACING because those can really hit
+ * __module_address() hard by doing a lot of stack unwinding; potentially from
+ * NMI context.
+ */
+
+__always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
+{
+	struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
+
+	return (unsigned long)layout->base;
+}
+
+__always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
+{
+	struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
+
+	return (unsigned long)layout->size;
+}
+
+__always_inline bool
+mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b)
+{
+	return __mod_tree_val(a) < __mod_tree_val(b);
+}
+
+__always_inline int
+mod_tree_comp(void *key, struct latch_tree_node *n)
+{
+	unsigned long val = (unsigned long)key;
+	unsigned long start, end;
+
+	start = __mod_tree_val(n);
+	if (val < start)
+		return -1;
+
+	end = start + __mod_tree_size(n);
+	if (val >= end)
+		return 1;
+
+	return 0;
+}
+
+const struct latch_tree_ops mod_tree_ops = {
+	.less = mod_tree_less,
+	.comp = mod_tree_comp,
+};
+
+noinline void __mod_tree_insert(struct mod_tree_node *node)
+{
+	latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops);
+}
+
+void __mod_tree_remove(struct mod_tree_node *node)
+{
+	latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops);
+}
+
+/*
+ * These modifications: insert, remove_init and remove; are serialized by the
+ * module_mutex.
+ */
+void mod_tree_insert(struct module *mod)
+{
+	mod->core_layout.mtn.mod = mod;
+	mod->init_layout.mtn.mod = mod;
+
+	__mod_tree_insert(&mod->core_layout.mtn);
+	if (mod->init_layout.size)
+		__mod_tree_insert(&mod->init_layout.mtn);
+}
+
+void mod_tree_remove_init(struct module *mod)
+{
+	if (mod->init_layout.size)
+		__mod_tree_remove(&mod->init_layout.mtn);
+}
+
+void mod_tree_remove(struct module *mod)
+{
+	__mod_tree_remove(&mod->core_layout.mtn);
+	mod_tree_remove_init(mod);
+}
+
+struct module *mod_find(unsigned long addr)
+{
+	struct latch_tree_node *ltn;
+
+	ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops);
+	if (!ltn)
+		return NULL;
+
+	return container_of(ltn, struct mod_tree_node, node)->mod;
+}
-- 
2.34.1

[RFC PATCH v3 05/13] module: Move arch strict rwx support to a separate file

[Aaron Tomlin]

No functional change.

This patch migrates applicable architecture code
that support strict module rwx from core module code
into kernel/module/arch_strict_rwx.c

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
 include/linux/module.h          | 17 +++++++++++
 kernel/module/Makefile          |  1 +
 kernel/module/arch_strict_rwx.c | 44 ++++++++++++++++++++++++++++
 kernel/module/main.c            | 51 ---------------------------------
 4 files changed, 62 insertions(+), 51 deletions(-)
 create mode 100644 kernel/module/arch_strict_rwx.c

diff --git a/include/linux/module.h b/include/linux/module.h
index 377bdb9952cf..35552164830d 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -339,6 +339,23 @@ struct module_layout {
 #endif
 };
 
+/*
+ * Modules' sections will be aligned on page boundaries
+ * to ensure complete separation of code and data, but
+ * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y
+ */
+#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
+# define debug_align(X) ALIGN(X, PAGE_SIZE)
+
+extern void frob_text(const struct module_layout *layout,
+		      int (*set_memory)(unsigned long start, int num_pages));
+extern void module_enable_x(const struct module *mod);
+#else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
+# define debug_align(X) (X)
+
+static void module_enable_x(const struct module *mod) { }
+#endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
+
 #ifdef CONFIG_MODULES_TREE_LOOKUP
 struct mod_tree_root {
 	struct latch_tree_root root;
diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index 5990d2e4566d..71341f30c3f2 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -9,3 +9,4 @@ obj-$(CONFIG_MODULE_SIG) += signing.o
 obj-$(CONFIG_MODULE_SIG_FORMAT) += signature.o
 obj-$(CONFIG_LIVEPATCH) += livepatch.o
 obj-$(CONFIG_MODULES_TREE_LOOKUP) += tree_lookup.o
+obj-$(CONFIG_ARCH_HAS_STRICT_MODULE_RWX) += arch_strict_rwx.o
diff --git a/kernel/module/arch_strict_rwx.c b/kernel/module/arch_strict_rwx.c
new file mode 100644
index 000000000000..9801cb4fef36
--- /dev/null
+++ b/kernel/module/arch_strict_rwx.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Module arch strict rwx
+ *
+ * Copyright (C) 2015 Rusty Russell
+ */
+
+#include <linux/module.h>
+#include <linux/set_memory.h>
+
+/*
+ * LKM RO/NX protection: protect module's text/ro-data
+ * from modification and any data from execution.
+ *
+ * General layout of module is:
+ *          [text] [read-only-data] [ro-after-init] [writable data]
+ * text_size -----^                ^               ^               ^
+ * ro_size ------------------------|               |               |
+ * ro_after_init_size -----------------------------|               |
+ * size -----------------------------------------------------------|
+ *
+ * These values are always page-aligned (as is base)
+ */
+
+/*
+ * Since some arches are moving towards PAGE_KERNEL module allocations instead
+ * of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() outside of the
+ * CONFIG_STRICT_MODULE_RWX block below because they are needed regardless of
+ * whether we are strict.
+ */
+void frob_text(const struct module_layout *layout,
+		      int (*set_memory)(unsigned long start, int num_pages))
+{
+	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
+	set_memory((unsigned long)layout->base,
+		   layout->text_size >> PAGE_SHIFT);
+}
+
+void module_enable_x(const struct module *mod)
+{
+	frob_text(&mod->core_layout, set_memory_x);
+	frob_text(&mod->init_layout, set_memory_x);
+}
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 5c7c3201b5b4..fbac043b07d7 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -13,7 +13,6 @@
 #include <linux/trace_events.h>
 #include <linux/init.h>
 #include <linux/kallsyms.h>
-#include <linux/buildid.h>
 #include <linux/file.h>
 #include <linux/fs.h>
 #include <linux/sysfs.h>
@@ -63,17 +62,6 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/module.h>
 
-/*
- * Modules' sections will be aligned on page boundaries
- * to ensure complete separation of code and data, but
- * only when CONFIG_ARCH_HAS_STRICT_MODULE_RWX=y
- */
-#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
-# define debug_align(X) ALIGN(X, PAGE_SIZE)
-#else
-# define debug_align(X) (X)
-#endif
-
 /*
  * Mutex protects:
  * 1) List of modules (also safely readable with preempt_disable),
@@ -1785,45 +1773,6 @@ static void mod_sysfs_teardown(struct module *mod)
 	mod_sysfs_fini(mod);
 }
 
-/*
- * LKM RO/NX protection: protect module's text/ro-data
- * from modification and any data from execution.
- *
- * General layout of module is:
- *          [text] [read-only-data] [ro-after-init] [writable data]
- * text_size -----^                ^               ^               ^
- * ro_size ------------------------|               |               |
- * ro_after_init_size -----------------------------|               |
- * size -----------------------------------------------------------|
- *
- * These values are always page-aligned (as is base)
- */
-
-/*
- * Since some arches are moving towards PAGE_KERNEL module allocations instead
- * of PAGE_KERNEL_EXEC, keep frob_text() and module_enable_x() outside of the
- * CONFIG_STRICT_MODULE_RWX block below because they are needed regardless of
- * whether we are strict.
- */
-#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX
-static void frob_text(const struct module_layout *layout,
-		      int (*set_memory)(unsigned long start, int num_pages))
-{
-	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
-	BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
-	set_memory((unsigned long)layout->base,
-		   layout->text_size >> PAGE_SHIFT);
-}
-
-static void module_enable_x(const struct module *mod)
-{
-	frob_text(&mod->core_layout, set_memory_x);
-	frob_text(&mod->init_layout, set_memory_x);
-}
-#else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
-static void module_enable_x(const struct module *mod) { }
-#endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
-
 #ifdef CONFIG_STRICT_MODULE_RWX
 static void frob_rodata(const struct module_layout *layout,
 			int (*set_memory)(unsigned long start, int num_pages))
-- 
2.34.1

[RFC PATCH v3 06/13] module: Move strict rwx support to a separate file

[Aaron Tomlin]

No functional change.

This patch migrates code that makes module text
and rodata memory read-only and non-text memory
non-executable from core module code into
kernel/module/strict_rwx.c.

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
 include/linux/module.h     | 22 ++++++++++
 kernel/module/Makefile     |  1 +
 kernel/module/main.c       | 84 --------------------------------------
 kernel/module/strict_rwx.c | 83 +++++++++++++++++++++++++++++++++++++
 4 files changed, 106 insertions(+), 84 deletions(-)
 create mode 100644 kernel/module/strict_rwx.c

diff --git a/include/linux/module.h b/include/linux/module.h
index 35552164830d..7bf93c0d87e6 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -356,6 +356,28 @@ extern void module_enable_x(const struct module *mod);
 static void module_enable_x(const struct module *mod) { }
 #endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */
 
+#ifdef CONFIG_STRICT_MODULE_RWX
+extern void frob_rodata(const struct module_layout *layout,
+			int (*set_memory)(unsigned long start, int num_pages));
+extern void frob_ro_after_init(const struct module_layout *layout,
+			       int (*set_memory)(unsigned long start, int num_pages));
+extern void frob_writable_data(const struct module_layout *layout,
+			       int (*set_memory)(unsigned long start, int num_pages));
+extern void module_enable_ro(const struct module *mod, bool after_init);
+extern void module_enable_nx(const struct module *mod);
+extern int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
+				       char *secstrings, struct module *mod);
+
+#else /* !CONFIG_STRICT_MODULE_RWX */
+static void module_enable_nx(const struct module *mod) { }
+static void module_enable_ro(const struct module *mod, bool after_init) {}
+static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
+				       char *secstrings, struct module *mod)
+{
+	return 0;
+}
+#endif /* CONFIG_STRICT_MODULE_RWX */
+
 #ifdef CONFIG_MODULES_TREE_LOOKUP
 struct mod_tree_root {
 	struct latch_tree_root root;
diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index 71341f30c3f2..c4198fcf4772 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -10,3 +10,4 @@ obj-$(CONFIG_MODULE_SIG_FORMAT) += signature.o
 obj-$(CONFIG_LIVEPATCH) += livepatch.o
 obj-$(CONFIG_MODULES_TREE_LOOKUP) += tree_lookup.o
 obj-$(CONFIG_ARCH_HAS_STRICT_MODULE_RWX) += arch_strict_rwx.o
+obj-$(CONFIG_STRICT_MODULE_RWX) += strict_rwx.o
diff --git a/kernel/module/main.c b/kernel/module/main.c
index fbac043b07d7..4f590b0c7aca 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -1773,90 +1773,6 @@ static void mod_sysfs_teardown(struct module *mod)
 	mod_sysfs_fini(mod);
 }
 
-#ifdef CONFIG_STRICT_MODULE_RWX
-static void frob_rodata(const struct module_layout *layout,
-			int (*set_memory)(unsigned long start, int num_pages))
-{
-	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
-	BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
-	BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
-	set_memory((unsigned long)layout->base + layout->text_size,
-		   (layout->ro_size - layout->text_size) >> PAGE_SHIFT);
-}
-
-static void frob_ro_after_init(const struct module_layout *layout,
-				int (*set_memory)(unsigned long start, int num_pages))
-{
-	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
-	BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
-	BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1));
-	set_memory((unsigned long)layout->base + layout->ro_size,
-		   (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT);
-}
-
-static void frob_writable_data(const struct module_layout *layout,
-			       int (*set_memory)(unsigned long start, int num_pages))
-{
-	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
-	BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1));
-	BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1));
-	set_memory((unsigned long)layout->base + layout->ro_after_init_size,
-		   (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT);
-}
-
-static void module_enable_ro(const struct module *mod, bool after_init)
-{
-	if (!rodata_enabled)
-		return;
-
-	set_vm_flush_reset_perms(mod->core_layout.base);
-	set_vm_flush_reset_perms(mod->init_layout.base);
-	frob_text(&mod->core_layout, set_memory_ro);
-
-	frob_rodata(&mod->core_layout, set_memory_ro);
-	frob_text(&mod->init_layout, set_memory_ro);
-	frob_rodata(&mod->init_layout, set_memory_ro);
-
-	if (after_init)
-		frob_ro_after_init(&mod->core_layout, set_memory_ro);
-}
-
-static void module_enable_nx(const struct module *mod)
-{
-	frob_rodata(&mod->core_layout, set_memory_nx);
-	frob_ro_after_init(&mod->core_layout, set_memory_nx);
-	frob_writable_data(&mod->core_layout, set_memory_nx);
-	frob_rodata(&mod->init_layout, set_memory_nx);
-	frob_writable_data(&mod->init_layout, set_memory_nx);
-}
-
-static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
-				       char *secstrings, struct module *mod)
-{
-	const unsigned long shf_wx = SHF_WRITE|SHF_EXECINSTR;
-	int i;
-
-	for (i = 0; i < hdr->e_shnum; i++) {
-		if ((sechdrs[i].sh_flags & shf_wx) == shf_wx) {
-			pr_err("%s: section %s (index %d) has invalid WRITE|EXEC flags\n",
-				mod->name, secstrings + sechdrs[i].sh_name, i);
-			return -ENOEXEC;
-		}
-	}
-
-	return 0;
-}
-
-#else /* !CONFIG_STRICT_MODULE_RWX */
-static void module_enable_nx(const struct module *mod) { }
-static void module_enable_ro(const struct module *mod, bool after_init) {}
-static int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
-				       char *secstrings, struct module *mod)
-{
-	return 0;
-}
-#endif /*  CONFIG_STRICT_MODULE_RWX */
-
 void __weak module_memfree(void *module_region)
 {
 	/*
diff --git a/kernel/module/strict_rwx.c b/kernel/module/strict_rwx.c
new file mode 100644
index 000000000000..39060021755a
--- /dev/null
+++ b/kernel/module/strict_rwx.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Module strict rwx
+ *
+ * Copyright (C) 2015 Rusty Russell
+ */
+
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/set_memory.h>
+
+void frob_rodata(const struct module_layout *layout,
+			int (*set_memory)(unsigned long start, int num_pages))
+{
+	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
+	set_memory((unsigned long)layout->base + layout->text_size,
+		   (layout->ro_size - layout->text_size) >> PAGE_SHIFT);
+}
+
+void frob_ro_after_init(const struct module_layout *layout,
+				int (*set_memory)(unsigned long start, int num_pages))
+{
+	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1));
+	set_memory((unsigned long)layout->base + layout->ro_size,
+		   (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT);
+}
+
+void frob_writable_data(const struct module_layout *layout,
+			       int (*set_memory)(unsigned long start, int num_pages))
+{
+	BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1));
+	BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1));
+	set_memory((unsigned long)layout->base + layout->ro_after_init_size,
+		   (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT);
+}
+
+void module_enable_ro(const struct module *mod, bool after_init)
+{
+	if (!rodata_enabled)
+		return;
+
+	set_vm_flush_reset_perms(mod->core_layout.base);
+	set_vm_flush_reset_perms(mod->init_layout.base);
+	frob_text(&mod->core_layout, set_memory_ro);
+
+	frob_rodata(&mod->core_layout, set_memory_ro);
+	frob_text(&mod->init_layout, set_memory_ro);
+	frob_rodata(&mod->init_layout, set_memory_ro);
+
+	if (after_init)
+		frob_ro_after_init(&mod->core_layout, set_memory_ro);
+}
+
+void module_enable_nx(const struct module *mod)
+{
+	frob_rodata(&mod->core_layout, set_memory_nx);
+	frob_ro_after_init(&mod->core_layout, set_memory_nx);
+	frob_writable_data(&mod->core_layout, set_memory_nx);
+	frob_rodata(&mod->init_layout, set_memory_nx);
+	frob_writable_data(&mod->init_layout, set_memory_nx);
+}
+
+int module_enforce_rwx_sections(Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
+				       char *secstrings, struct module *mod)
+{
+	const unsigned long shf_wx = SHF_WRITE|SHF_EXECINSTR;
+	int i;
+
+	for (i = 0; i < hdr->e_shnum; i++) {
+		if ((sechdrs[i].sh_flags & shf_wx) == shf_wx) {
+			pr_err("%s: section %s (index %d) has invalid WRITE|EXEC flags\n",
+				mod->name, secstrings + sechdrs[i].sh_name, i);
+			return -ENOEXEC;
+		}
+	}
+
+	return 0;
+}
-- 
2.34.1

[RFC PATCH v3 07/13] module: Move extra signature support out of core code

[Aaron Tomlin]

No functional change.

This patch migrates additional module signature check
code from core module code into kernel/module/signing.c.

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
 include/linux/module.h   |  5 ++-
 kernel/module/internal.h |  9 +++++
 kernel/module/main.c     | 87 ----------------------------------------
 kernel/module/signing.c  | 75 ++++++++++++++++++++++++++++++++++
 4 files changed, 87 insertions(+), 89 deletions(-)

diff --git a/include/linux/module.h b/include/linux/module.h
index 7bf93c0d87e6..68dabc036100 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -758,8 +758,8 @@ static inline bool set_livepatch_module(struct module *mod)
 }
 #endif /* CONFIG_LIVEPATCH */
 
-bool is_module_sig_enforced(void);
-void set_module_sig_enforced(void);
+extern bool is_module_sig_enforced(void);
+extern void set_module_sig_enforced(void);
 
 #else /* !CONFIG_MODULES... */
 
@@ -949,6 +949,7 @@ static inline bool module_sig_ok(struct module *module)
 {
 	return true;
 }
+#define sig_enforce false
 #endif	/* CONFIG_MODULE_SIG */
 
 int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index 0cd624179545..5aab87716d9f 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -80,3 +80,12 @@ static inline void module_decompress_cleanup(struct load_info *info)
 {
 }
 #endif
+
+#ifdef CONFIG_MODULE_SIG
+extern int module_sig_check(struct load_info *info, int flags);
+#else /* !CONFIG_MODULE_SIG */
+static int module_sig_check(struct load_info *info, int flags)
+{
+	return 0;
+}
+#endif /* !CONFIG_MODULE_SIG */
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 4f590b0c7aca..36ed4dd64cac 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -22,7 +22,6 @@
 #include <linux/vmalloc.h>
 #include <linux/elf.h>
 #include <linux/proc_fs.h>
-#include <linux/security.h>
 #include <linux/seq_file.h>
 #include <linux/syscalls.h>
 #include <linux/fcntl.h>
@@ -114,28 +113,6 @@ static void module_assert_mutex_or_preempt(void)
 #endif
 }
 
-#ifdef CONFIG_MODULE_SIG
-static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE);
-module_param(sig_enforce, bool_enable_only, 0644);
-
-void set_module_sig_enforced(void)
-{
-	sig_enforce = true;
-}
-#else
-#define sig_enforce false
-#endif
-
-/*
- * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
- * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
- */
-bool is_module_sig_enforced(void)
-{
-	return sig_enforce;
-}
-EXPORT_SYMBOL(is_module_sig_enforced);
-
 /* Block module loading/unloading? */
 int modules_disabled = 0;
 core_param(nomodule, modules_disabled, bint, 0);
@@ -2516,70 +2493,6 @@ static inline void kmemleak_load_module(const struct module *mod,
 }
 #endif
 
-#ifdef CONFIG_MODULE_SIG
-static int module_sig_check(struct load_info *info, int flags)
-{
-	int err = -ENODATA;
-	const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
-	const char *reason;
-	const void *mod = info->hdr;
-	bool mangled_module = flags & (MODULE_INIT_IGNORE_MODVERSIONS |
-				       MODULE_INIT_IGNORE_VERMAGIC);
-	/*
-	 * Do not allow mangled modules as a module with version information
-	 * removed is no longer the module that was signed.
-	 */
-	if (!mangled_module &&
-	    info->len > markerlen &&
-	    memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
-		/* We truncate the module to discard the signature */
-		info->len -= markerlen;
-		err = mod_verify_sig(mod, info);
-		if (!err) {
-			info->sig_ok = true;
-			return 0;
-		}
-	}
-
-	/*
-	 * We don't permit modules to be loaded into the trusted kernels
-	 * without a valid signature on them, but if we're not enforcing,
-	 * certain errors are non-fatal.
-	 */
-	switch (err) {
-	case -ENODATA:
-		reason = "unsigned module";
-		break;
-	case -ENOPKG:
-		reason = "module with unsupported crypto";
-		break;
-	case -ENOKEY:
-		reason = "module with unavailable key";
-		break;
-
-	default:
-		/*
-		 * All other errors are fatal, including lack of memory,
-		 * unparseable signatures, and signature check failures --
-		 * even if signatures aren't required.
-		 */
-		return err;
-	}
-
-	if (is_module_sig_enforced()) {
-		pr_notice("Loading of %s is rejected\n", reason);
-		return -EKEYREJECTED;
-	}
-
-	return security_locked_down(LOCKDOWN_MODULE_SIGNATURE);
-}
-#else /* !CONFIG_MODULE_SIG */
-static int module_sig_check(struct load_info *info, int flags)
-{
-	return 0;
-}
-#endif /* !CONFIG_MODULE_SIG */
-
 static int validate_section_offset(struct load_info *info, Elf_Shdr *shdr)
 {
 #if defined(CONFIG_64BIT)
diff --git a/kernel/module/signing.c b/kernel/module/signing.c
index 8aeb6d2ee94b..ff41541e982a 100644
--- a/kernel/module/signing.c
+++ b/kernel/module/signing.c
@@ -11,9 +11,28 @@
 #include <linux/module_signature.h>
 #include <linux/string.h>
 #include <linux/verification.h>
+#include <linux/security.h>
 #include <crypto/public_key.h>
 #include "internal.h"
 
+static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE);
+module_param(sig_enforce, bool_enable_only, 0644);
+
+/*
+ * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
+ * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
+ */
+bool is_module_sig_enforced(void)
+{
+	return sig_enforce;
+}
+EXPORT_SYMBOL(is_module_sig_enforced);
+
+void set_module_sig_enforced(void)
+{
+	sig_enforce = true;
+}
+
 /*
  * Verify the signature on a module.
  */
@@ -43,3 +62,59 @@ int mod_verify_sig(const void *mod, struct load_info *info)
 				      VERIFYING_MODULE_SIGNATURE,
 				      NULL, NULL);
 }
+
+int module_sig_check(struct load_info *info, int flags)
+{
+	int err = -ENODATA;
+	const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
+	const char *reason;
+	const void *mod = info->hdr;
+
+	/*
+	 * Require flags == 0, as a module with version information
+	 * removed is no longer the module that was signed
+	 */
+	if (flags == 0 &&
+	    info->len > markerlen &&
+	    memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
+		/* We truncate the module to discard the signature */
+		info->len -= markerlen;
+		err = mod_verify_sig(mod, info);
+		if (!err) {
+			info->sig_ok = true;
+			return 0;
+		}
+	}
+
+	/*
+	 * We don't permit modules to be loaded into the trusted kernels
+	 * without a valid signature on them, but if we're not enforcing,
+	 * certain errors are non-fatal.
+	 */
+	switch (err) {
+	case -ENODATA:
+		reason = "unsigned module";
+		break;
+	case -ENOPKG:
+		reason = "module with unsupported crypto";
+		break;
+	case -ENOKEY:
+		reason = "module with unavailable key";
+		break;
+
+	default:
+		/*
+		 * All other errors are fatal, including lack of memory,
+		 * unparseable signatures, and signature check failures --
+		 * even if signatures aren't required.
+		 */
+		return err;
+	}
+
+	if (is_module_sig_enforced()) {
+		pr_notice("Loading of %s is rejected\n", reason);
+		return -EKEYREJECTED;
+	}
+
+	return security_locked_down(LOCKDOWN_MODULE_SIGNATURE);
+}
-- 
2.34.1

[RFC PATCH v3 08/13] module: Move kmemleak support to a separate file

[Aaron Tomlin]

No functional change.

This patch migrates kmemleak code out of core module
code into kernel/module/debug_kmemleak.c

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
 kernel/module/Makefile         |  1 +
 kernel/module/debug_kmemleak.c | 30 ++++++++++++++++++++++++++++++
 kernel/module/internal.h       |  8 ++++++++
 kernel/module/main.c           | 27 ---------------------------
 4 files changed, 39 insertions(+), 27 deletions(-)
 create mode 100644 kernel/module/debug_kmemleak.c

diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index c4198fcf4772..3901f0713f22 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_LIVEPATCH) += livepatch.o
 obj-$(CONFIG_MODULES_TREE_LOOKUP) += tree_lookup.o
 obj-$(CONFIG_ARCH_HAS_STRICT_MODULE_RWX) += arch_strict_rwx.o
 obj-$(CONFIG_STRICT_MODULE_RWX) += strict_rwx.o
+obj-$(CONFIG_DEBUG_KMEMLEAK) += debug_kmemleak.o
diff --git a/kernel/module/debug_kmemleak.c b/kernel/module/debug_kmemleak.c
new file mode 100644
index 000000000000..e896c2268011
--- /dev/null
+++ b/kernel/module/debug_kmemleak.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Module kmemleak support
+ *
+ * Copyright (C) 2009 Catalin Marinas
+ */
+
+#include <linux/module.h>
+#include <linux/kmemleak.h>
+#include "internal.h"
+
+void kmemleak_load_module(const struct module *mod,
+				 const struct load_info *info)
+{
+	unsigned int i;
+
+	/* only scan the sections containing data */
+	kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
+
+	for (i = 1; i < info->hdr->e_shnum; i++) {
+		/* Scan all writable sections that's not executable */
+		if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
+		    !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
+		    (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
+			continue;
+
+		kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
+				   info->sechdrs[i].sh_size, GFP_KERNEL);
+	}
+}
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index 5aab87716d9f..ef9513070b88 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -6,6 +6,7 @@
  */
 
 #include <linux/elf.h>
+#include <linux/compiler.h>
 #include <asm/module.h>
 #include <linux/mutex.h>
 
@@ -89,3 +90,10 @@ static int module_sig_check(struct load_info *info, int flags)
 	return 0;
 }
 #endif /* !CONFIG_MODULE_SIG */
+
+#ifdef CONFIG_DEBUG_KMEMLEAK
+extern void kmemleak_load_module(const struct module *mod, const struct load_info *info);
+#else /* !CONFIG_DEBUG_KMEMLEAK */
+static inline void __maybe_unused kmemleak_load_module(const struct module *mod,
+						       const struct load_info *info) { }
+#endif /* CONFIG_DEBUG_KMEMLEAK */
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 36ed4dd64cac..6fb1c885d9c2 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -2466,33 +2466,6 @@ bool __weak module_exit_section(const char *name)
 	return strstarts(name, ".exit");
 }
 
-#ifdef CONFIG_DEBUG_KMEMLEAK
-static void kmemleak_load_module(const struct module *mod,
-				 const struct load_info *info)
-{
-	unsigned int i;
-
-	/* only scan the sections containing data */
-	kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
-
-	for (i = 1; i < info->hdr->e_shnum; i++) {
-		/* Scan all writable sections that's not executable */
-		if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
-		    !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
-		    (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
-			continue;
-
-		kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
-				   info->sechdrs[i].sh_size, GFP_KERNEL);
-	}
-}
-#else
-static inline void kmemleak_load_module(const struct module *mod,
-					const struct load_info *info)
-{
-}
-#endif
-
 static int validate_section_offset(struct load_info *info, Elf_Shdr *shdr)
 {
 #if defined(CONFIG_64BIT)
-- 
2.34.1

[RFC PATCH v3 09/13] module: Move kallsyms support into a separate file

[Aaron Tomlin]

No functional change.

This patch migrates kallsyms code out of core module
code kernel/module/kallsyms.c

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
 kernel/module/Makefile   |   1 +
 kernel/module/internal.h |  27 ++
 kernel/module/kallsyms.c | 502 +++++++++++++++++++++++++++++++++++++
 kernel/module/main.c     | 516 +--------------------------------------
 4 files changed, 534 insertions(+), 512 deletions(-)
 create mode 100644 kernel/module/kallsyms.c

diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index 3901f0713f22..5fb2a7fec743 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_MODULES_TREE_LOOKUP) += tree_lookup.o
 obj-$(CONFIG_ARCH_HAS_STRICT_MODULE_RWX) += arch_strict_rwx.o
 obj-$(CONFIG_STRICT_MODULE_RWX) += strict_rwx.o
 obj-$(CONFIG_DEBUG_KMEMLEAK) += debug_kmemleak.o
+obj-$(CONFIG_KALLSYMS) += kallsyms.o
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index ef9513070b88..e69d0249df6b 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -57,6 +57,11 @@ struct load_info {
 };
 
 extern int mod_verify_sig(const void *mod, struct load_info *info);
+extern struct module *find_module_all(const char *name, size_t len, bool even_unformed);
+extern unsigned long kernel_symbol_value(const struct kernel_symbol *sym);
+extern int cmp_name(const void *name, const void *sym);
+extern long get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr,
+		       unsigned int section);
 
 #ifdef CONFIG_LIVEPATCH
 extern int copy_module_elf(struct module *mod, struct load_info *info);
@@ -97,3 +102,25 @@ extern void kmemleak_load_module(const struct module *mod, const struct load_inf
 static inline void __maybe_unused kmemleak_load_module(const struct module *mod,
 						       const struct load_info *info) { }
 #endif /* CONFIG_DEBUG_KMEMLEAK */
+
+#ifdef CONFIG_KALLSYMS
+#ifdef CONFIG_STACKTRACE_BUILD_ID
+extern void init_build_id(struct module *mod, const struct load_info *info);
+#else /* !CONFIG_STACKTRACE_BUILD_ID */
+static inline void init_build_id(struct module *mod, const struct load_info *info) { }
+
+#endif
+extern void layout_symtab(struct module *mod, struct load_info *info);
+extern void add_kallsyms(struct module *mod, const struct load_info *info);
+extern bool sect_empty(const Elf_Shdr *sect);
+extern const char *find_kallsyms_symbol(struct module *mod, unsigned long addr,
+					unsigned long *size, unsigned long *offset);
+#else /* !CONFIG_KALLSYMS */
+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) { }
+static inline char *find_kallsyms_symbol(struct module *mod, unsigned long addr,
+					 unsigned long *size, unsigned long *offset)
+{
+	return NULL;
+}
+#endif /* CONFIG_KALLSYMS */
diff --git a/kernel/module/kallsyms.c b/kernel/module/kallsyms.c
new file mode 100644
index 000000000000..ed28f6310701
--- /dev/null
+++ b/kernel/module/kallsyms.c
@@ -0,0 +1,502 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Module kallsyms support
+ *
+ * Copyright (C) 2010 Rusty Russell
+ */
+
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/buildid.h>
+#include <linux/bsearch.h>
+#include "internal.h"
+
+/* Lookup exported symbol in given range of kernel_symbols */
+static const struct kernel_symbol *lookup_exported_symbol(const char *name,
+							  const struct kernel_symbol *start,
+							  const struct kernel_symbol *stop)
+{
+	return bsearch(name, start, stop - start,
+			sizeof(struct kernel_symbol), cmp_name);
+}
+
+static int is_exported(const char *name, unsigned long value,
+		       const struct module *mod)
+{
+	const struct kernel_symbol *ks;
+
+	if (!mod)
+		ks = lookup_exported_symbol(name, __start___ksymtab, __stop___ksymtab);
+	else
+		ks = lookup_exported_symbol(name, mod->syms, mod->syms + mod->num_syms);
+
+	return ks != NULL && kernel_symbol_value(ks) == value;
+}
+
+/* As per nm */
+static char elf_type(const Elf_Sym *sym, const struct load_info *info)
+{
+	const Elf_Shdr *sechdrs = info->sechdrs;
+
+	if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
+		if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
+			return 'v';
+		else
+			return 'w';
+	}
+	if (sym->st_shndx == SHN_UNDEF)
+		return 'U';
+	if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu)
+		return 'a';
+	if (sym->st_shndx >= SHN_LORESERVE)
+		return '?';
+	if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
+		return 't';
+	if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
+	    && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
+		if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
+			return 'r';
+		else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
+			return 'g';
+		else
+			return 'd';
+	}
+	if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
+		if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
+			return 's';
+		else
+			return 'b';
+	}
+	if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
+		      ".debug")) {
+		return 'n';
+	}
+	return '?';
+}
+
+static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
+			unsigned int shnum, unsigned int pcpundx)
+{
+	const Elf_Shdr *sec;
+
+	if (src->st_shndx == SHN_UNDEF
+	    || src->st_shndx >= shnum
+	    || !src->st_name)
+		return false;
+
+#ifdef CONFIG_KALLSYMS_ALL
+	if (src->st_shndx == pcpundx)
+		return true;
+#endif
+
+	sec = sechdrs + src->st_shndx;
+	if (!(sec->sh_flags & SHF_ALLOC)
+#ifndef CONFIG_KALLSYMS_ALL
+	    || !(sec->sh_flags & SHF_EXECINSTR)
+#endif
+	    || (sec->sh_entsize & INIT_OFFSET_MASK))
+		return false;
+
+	return true;
+}
+
+/*
+ * We only allocate and copy the strings needed by the parts of symtab
+ * we keep.  This is simple, but has the effect of making multiple
+ * copies of duplicates.  We could be more sophisticated, see
+ * linux-kernel thread starting with
+ * <73defb5e4bca04a6431392cc341112b1@localhost>.
+ */
+void layout_symtab(struct module *mod, struct load_info *info)
+{
+	Elf_Shdr *symsect = info->sechdrs + info->index.sym;
+	Elf_Shdr *strsect = info->sechdrs + info->index.str;
+	const Elf_Sym *src;
+	unsigned int i, nsrc, ndst, strtab_size = 0;
+
+	/* Put symbol section at end of init part of module. */
+	symsect->sh_flags |= SHF_ALLOC;
+	symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect,
+					 info->index.sym) | INIT_OFFSET_MASK;
+	pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
+
+	src = (void *)info->hdr + symsect->sh_offset;
+	nsrc = symsect->sh_size / sizeof(*src);
+
+	/* Compute total space required for the core symbols' strtab. */
+	for (ndst = i = 0; i < nsrc; i++) {
+		if (i == 0 || is_livepatch_module(mod) ||
+		    is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
+				   info->index.pcpu)) {
+			strtab_size += strlen(&info->strtab[src[i].st_name])+1;
+			ndst++;
+		}
+	}
+
+	/* Append room for core symbols at end of core part. */
+	info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1);
+	info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym);
+	mod->core_layout.size += strtab_size;
+	info->core_typeoffs = mod->core_layout.size;
+	mod->core_layout.size += ndst * sizeof(char);
+	mod->core_layout.size = debug_align(mod->core_layout.size);
+
+	/* Put string table section at end of init part of module. */
+	strsect->sh_flags |= SHF_ALLOC;
+	strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect,
+					 info->index.str) | INIT_OFFSET_MASK;
+	pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
+
+	/* We'll tack temporary mod_kallsyms on the end. */
+	mod->init_layout.size = ALIGN(mod->init_layout.size,
+				      __alignof__(struct mod_kallsyms));
+	info->mod_kallsyms_init_off = mod->init_layout.size;
+	mod->init_layout.size += sizeof(struct mod_kallsyms);
+	info->init_typeoffs = mod->init_layout.size;
+	mod->init_layout.size += nsrc * sizeof(char);
+	mod->init_layout.size = debug_align(mod->init_layout.size);
+}
+
+/*
+ * We use the full symtab and strtab which layout_symtab arranged to
+ * be appended to the init section.  Later we switch to the cut-down
+ * core-only ones.
+ */
+void add_kallsyms(struct module *mod, const struct load_info *info)
+{
+	unsigned int i, ndst;
+	const Elf_Sym *src;
+	Elf_Sym *dst;
+	char *s;
+	Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
+
+	/* Set up to point into init section. */
+	mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off;
+
+	mod->kallsyms->symtab = (void *)symsec->sh_addr;
+	mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
+	/* Make sure we get permanent strtab: don't use info->strtab. */
+	mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
+	mod->kallsyms->typetab = mod->init_layout.base + info->init_typeoffs;
+
+	/*
+	 * Now populate the cut down core kallsyms for after init
+	 * and set types up while we still have access to sections.
+	 */
+	mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs;
+	mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs;
+	mod->core_kallsyms.typetab = mod->core_layout.base + info->core_typeoffs;
+	src = mod->kallsyms->symtab;
+	for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) {
+		mod->kallsyms->typetab[i] = elf_type(src + i, info);
+		if (i == 0 || is_livepatch_module(mod) ||
+		    is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
+				   info->index.pcpu)) {
+			mod->core_kallsyms.typetab[ndst] =
+			    mod->kallsyms->typetab[i];
+			dst[ndst] = src[i];
+			dst[ndst++].st_name = s - mod->core_kallsyms.strtab;
+			s += strscpy(s, &mod->kallsyms->strtab[src[i].st_name],
+				     KSYM_NAME_LEN) + 1;
+		}
+	}
+	mod->core_kallsyms.num_symtab = ndst;
+}
+
+inline bool sect_empty(const Elf_Shdr *sect)
+{
+	return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
+}
+
+#ifdef CONFIG_STACKTRACE_BUILD_ID
+void init_build_id(struct module *mod, const struct load_info *info)
+{
+	const Elf_Shdr *sechdr;
+	unsigned int i;
+
+	for (i = 0; i < info->hdr->e_shnum; i++) {
+		sechdr = &info->sechdrs[i];
+		if (!sect_empty(sechdr) && sechdr->sh_type == SHT_NOTE &&
+		    !build_id_parse_buf((void *)sechdr->sh_addr, mod->build_id,
+					sechdr->sh_size))
+			break;
+	}
+}
+#endif
+
+/*
+ * This ignores the intensely annoying "mapping symbols" found
+ * in ARM ELF files: $a, $t and $d.
+ */
+static inline int is_arm_mapping_symbol(const char *str)
+{
+	if (str[0] == '.' && str[1] == 'L')
+		return true;
+	return str[0] == '$' && strchr("axtd", str[1])
+	       && (str[2] == '\0' || str[2] == '.');
+}
+
+static const char *kallsyms_symbol_name(struct mod_kallsyms *kallsyms, unsigned int symnum)
+{
+	return kallsyms->strtab + kallsyms->symtab[symnum].st_name;
+}
+
+/*
+ * Given a module and address, find the corresponding symbol and return its name
+ * while providing its size and offset if needed.
+ */
+const char *find_kallsyms_symbol(struct module *mod,
+					unsigned long addr,
+					unsigned long *size,
+					unsigned long *offset)
+{
+	unsigned int i, best = 0;
+	unsigned long nextval, bestval;
+	struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
+
+	/* At worse, next value is at end of module */
+	if (within_module_init(addr, mod))
+		nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size;
+	else
+		nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size;
+
+	bestval = kallsyms_symbol_value(&kallsyms->symtab[best]);
+
+	/*
+	 * Scan for closest preceding symbol, and next symbol. (ELF
+	 * starts real symbols at 1).
+	 */
+	for (i = 1; i < kallsyms->num_symtab; i++) {
+		const Elf_Sym *sym = &kallsyms->symtab[i];
+		unsigned long thisval = kallsyms_symbol_value(sym);
+
+		if (sym->st_shndx == SHN_UNDEF)
+			continue;
+
+		/*
+		 * We ignore unnamed symbols: they're uninformative
+		 * and inserted at a whim.
+		 */
+		if (*kallsyms_symbol_name(kallsyms, i) == '\0'
+		    || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms, i)))
+			continue;
+
+		if (thisval <= addr && thisval > bestval) {
+			best = i;
+			bestval = thisval;
+		}
+		if (thisval > addr && thisval < nextval)
+			nextval = thisval;
+	}
+
+	if (!best)
+		return NULL;
+
+	if (size)
+		*size = nextval - bestval;
+	if (offset)
+		*offset = addr - bestval;
+
+	return kallsyms_symbol_name(kallsyms, best);
+}
+
+void * __weak dereference_module_function_descriptor(struct module *mod,
+						     void *ptr)
+{
+	return ptr;
+}
+
+/*
+ * For kallsyms to ask for address resolution.  NULL means not found.  Careful
+ * not to lock to avoid deadlock on oopses, simply disable preemption.
+ */
+const char *module_address_lookup(unsigned long addr,
+			    unsigned long *size,
+			    unsigned long *offset,
+			    char **modname,
+			    const unsigned char **modbuildid,
+			    char *namebuf)
+{
+	const char *ret = NULL;
+	struct module *mod;
+
+	preempt_disable();
+	mod = __module_address(addr);
+	if (mod) {
+		if (modname)
+			*modname = mod->name;
+		if (modbuildid) {
+#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
+			*modbuildid = mod->build_id;
+#else
+			*modbuildid = NULL;
+#endif
+		}
+
+		ret = find_kallsyms_symbol(mod, addr, size, offset);
+	}
+	/* Make a copy in here where it's safe */
+	if (ret) {
+		strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
+		ret = namebuf;
+	}
+	preempt_enable();
+
+	return ret;
+}
+
+int lookup_module_symbol_name(unsigned long addr, char *symname)
+{
+	struct module *mod;
+
+	preempt_disable();
+	list_for_each_entry_rcu(mod, &modules, list) {
+		if (mod->state == MODULE_STATE_UNFORMED)
+			continue;
+		if (within_module(addr, mod)) {
+			const char *sym;
+
+			sym = find_kallsyms_symbol(mod, addr, NULL, NULL);
+			if (!sym)
+				goto out;
+
+			strscpy(symname, sym, KSYM_NAME_LEN);
+			preempt_enable();
+			return 0;
+		}
+	}
+out:
+	preempt_enable();
+	return -ERANGE;
+}
+
+int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
+			unsigned long *offset, char *modname, char *name)
+{
+	struct module *mod;
+
+	preempt_disable();
+	list_for_each_entry_rcu(mod, &modules, list) {
+		if (mod->state == MODULE_STATE_UNFORMED)
+			continue;
+		if (within_module(addr, mod)) {
+			const char *sym;
+
+			sym = find_kallsyms_symbol(mod, addr, size, offset);
+			if (!sym)
+				goto out;
+			if (modname)
+				strscpy(modname, mod->name, MODULE_NAME_LEN);
+			if (name)
+				strscpy(name, sym, KSYM_NAME_LEN);
+			preempt_enable();
+			return 0;
+		}
+	}
+out:
+	preempt_enable();
+	return -ERANGE;
+}
+
+int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
+			char *name, char *module_name, int *exported)
+{
+	struct module *mod;
+
+	preempt_disable();
+	list_for_each_entry_rcu(mod, &modules, list) {
+		struct mod_kallsyms *kallsyms;
+
+		if (mod->state == MODULE_STATE_UNFORMED)
+			continue;
+		kallsyms = rcu_dereference_sched(mod->kallsyms);
+		if (symnum < kallsyms->num_symtab) {
+			const Elf_Sym *sym = &kallsyms->symtab[symnum];
+
+			*value = kallsyms_symbol_value(sym);
+			*type = kallsyms->typetab[symnum];
+			strscpy(name, kallsyms_symbol_name(kallsyms, symnum), KSYM_NAME_LEN);
+			strscpy(module_name, mod->name, MODULE_NAME_LEN);
+			*exported = is_exported(name, *value, mod);
+			preempt_enable();
+			return 0;
+		}
+		symnum -= kallsyms->num_symtab;
+	}
+	preempt_enable();
+	return -ERANGE;
+}
+
+/* Given a module and name of symbol, find and return the symbol's value */
+static unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name)
+{
+	unsigned int i;
+	struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
+
+	for (i = 0; i < kallsyms->num_symtab; i++) {
+		const Elf_Sym *sym = &kallsyms->symtab[i];
+
+		if (strcmp(name, kallsyms_symbol_name(kallsyms, i)) == 0 &&
+		    sym->st_shndx != SHN_UNDEF)
+			return kallsyms_symbol_value(sym);
+	}
+	return 0;
+}
+
+/* Look for this name: can be of form module:name. */
+unsigned long module_kallsyms_lookup_name(const char *name)
+{
+	struct module *mod;
+	char *colon;
+	unsigned long ret = 0;
+
+	/* Don't lock: we're in enough trouble already. */
+	preempt_disable();
+	if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) {
+		if ((mod = find_module_all(name, colon - name, false)) != NULL)
+			ret = find_kallsyms_symbol_value(mod, colon+1);
+	} else {
+		list_for_each_entry_rcu(mod, &modules, list) {
+			if (mod->state == MODULE_STATE_UNFORMED)
+				continue;
+			if ((ret = find_kallsyms_symbol_value(mod, name)) != 0)
+				break;
+		}
+	}
+	preempt_enable();
+	return ret;
+}
+
+#ifdef CONFIG_LIVEPATCH
+int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
+					     struct module *, unsigned long),
+				   void *data)
+{
+	struct module *mod;
+	unsigned int i;
+	int ret = 0;
+
+	mutex_lock(&module_mutex);
+	list_for_each_entry(mod, &modules, list) {
+		/* We hold module_mutex: no need for rcu_dereference_sched */
+		struct mod_kallsyms *kallsyms = mod->kallsyms;
+
+		if (mod->state == MODULE_STATE_UNFORMED)
+			continue;
+		for (i = 0; i < kallsyms->num_symtab; i++) {
+			const Elf_Sym *sym = &kallsyms->symtab[i];
+
+			if (sym->st_shndx == SHN_UNDEF)
+				continue;
+
+			ret = fn(data, kallsyms_symbol_name(kallsyms, i),
+				 mod, kallsyms_symbol_value(sym));
+			if (ret != 0)
+				goto out;
+		}
+	}
+out:
+	mutex_unlock(&module_mutex);
+	return ret;
+}
+#endif /* CONFIG_LIVEPATCH */
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 6fb1c885d9c2..054f34de4e6c 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -275,7 +275,7 @@ static bool check_exported_symbol(const struct symsearch *syms,
 	return true;
 }
 
-static unsigned long kernel_symbol_value(const struct kernel_symbol *sym)
+unsigned long kernel_symbol_value(const struct kernel_symbol *sym)
 {
 #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
 	return (unsigned long)offset_to_ptr(&sym->value_offset);
@@ -304,7 +304,7 @@ static const char *kernel_symbol_namespace(const struct kernel_symbol *sym)
 #endif
 }
 
-static int cmp_name(const void *name, const void *sym)
+int cmp_name(const void *name, const void *sym)
 {
 	return strcmp(name, kernel_symbol_name(sym));
 }
@@ -374,7 +374,7 @@ static bool find_symbol(struct find_symbol_arg *fsa)
  * Search for module by name: must hold module_mutex (or preempt disabled
  * for read-only access).
  */
-static struct module *find_module_all(const char *name, size_t len,
+struct module *find_module_all(const char *name, size_t len,
 				      bool even_unformed)
 {
 	struct module *mod;
@@ -1281,13 +1281,6 @@ resolve_symbol_wait(struct module *mod,
 	return ksym;
 }
 
-#ifdef CONFIG_KALLSYMS
-static inline bool sect_empty(const Elf_Shdr *sect)
-{
-	return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
-}
-#endif
-
 /*
  * /sys/module/foo/sections stuff
  * J. Corbet <corbet@lwn.net>
@@ -2012,7 +2005,7 @@ unsigned int __weak arch_mod_section_prepend(struct module *mod,
 }
 
 /* Update size with this section: return offset. */
-static long get_offset(struct module *mod, unsigned int *size,
+long get_offset(struct module *mod, unsigned int *size,
 		       Elf_Shdr *sechdr, unsigned int section)
 {
 	long ret;
@@ -2214,228 +2207,6 @@ static void free_modinfo(struct module *mod)
 	}
 }
 
-#ifdef CONFIG_KALLSYMS
-
-/* Lookup exported symbol in given range of kernel_symbols */
-static const struct kernel_symbol *lookup_exported_symbol(const char *name,
-							  const struct kernel_symbol *start,
-							  const struct kernel_symbol *stop)
-{
-	return bsearch(name, start, stop - start,
-			sizeof(struct kernel_symbol), cmp_name);
-}
-
-static int is_exported(const char *name, unsigned long value,
-		       const struct module *mod)
-{
-	const struct kernel_symbol *ks;
-	if (!mod)
-		ks = lookup_exported_symbol(name, __start___ksymtab, __stop___ksymtab);
-	else
-		ks = lookup_exported_symbol(name, mod->syms, mod->syms + mod->num_syms);
-
-	return ks != NULL && kernel_symbol_value(ks) == value;
-}
-
-/* As per nm */
-static char elf_type(const Elf_Sym *sym, const struct load_info *info)
-{
-	const Elf_Shdr *sechdrs = info->sechdrs;
-
-	if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
-		if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
-			return 'v';
-		else
-			return 'w';
-	}
-	if (sym->st_shndx == SHN_UNDEF)
-		return 'U';
-	if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu)
-		return 'a';
-	if (sym->st_shndx >= SHN_LORESERVE)
-		return '?';
-	if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
-		return 't';
-	if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
-	    && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
-		if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
-			return 'r';
-		else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
-			return 'g';
-		else
-			return 'd';
-	}
-	if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
-		if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
-			return 's';
-		else
-			return 'b';
-	}
-	if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
-		      ".debug")) {
-		return 'n';
-	}
-	return '?';
-}
-
-static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
-			unsigned int shnum, unsigned int pcpundx)
-{
-	const Elf_Shdr *sec;
-
-	if (src->st_shndx == SHN_UNDEF
-	    || src->st_shndx >= shnum
-	    || !src->st_name)
-		return false;
-
-#ifdef CONFIG_KALLSYMS_ALL
-	if (src->st_shndx == pcpundx)
-		return true;
-#endif
-
-	sec = sechdrs + src->st_shndx;
-	if (!(sec->sh_flags & SHF_ALLOC)
-#ifndef CONFIG_KALLSYMS_ALL
-	    || !(sec->sh_flags & SHF_EXECINSTR)
-#endif
-	    || (sec->sh_entsize & INIT_OFFSET_MASK))
-		return false;
-
-	return true;
-}
-
-/*
- * We only allocate and copy the strings needed by the parts of symtab
- * we keep.  This is simple, but has the effect of making multiple
- * copies of duplicates.  We could be more sophisticated, see
- * linux-kernel thread starting with
- * <73defb5e4bca04a6431392cc341112b1@localhost>.
- */
-static void layout_symtab(struct module *mod, struct load_info *info)
-{
-	Elf_Shdr *symsect = info->sechdrs + info->index.sym;
-	Elf_Shdr *strsect = info->sechdrs + info->index.str;
-	const Elf_Sym *src;
-	unsigned int i, nsrc, ndst, strtab_size = 0;
-
-	/* Put symbol section at end of init part of module. */
-	symsect->sh_flags |= SHF_ALLOC;
-	symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect,
-					 info->index.sym) | INIT_OFFSET_MASK;
-	pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
-
-	src = (void *)info->hdr + symsect->sh_offset;
-	nsrc = symsect->sh_size / sizeof(*src);
-
-	/* Compute total space required for the core symbols' strtab. */
-	for (ndst = i = 0; i < nsrc; i++) {
-		if (i == 0 || is_livepatch_module(mod) ||
-		    is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
-				   info->index.pcpu)) {
-			strtab_size += strlen(&info->strtab[src[i].st_name])+1;
-			ndst++;
-		}
-	}
-
-	/* Append room for core symbols at end of core part. */
-	info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1);
-	info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym);
-	mod->core_layout.size += strtab_size;
-	info->core_typeoffs = mod->core_layout.size;
-	mod->core_layout.size += ndst * sizeof(char);
-	mod->core_layout.size = debug_align(mod->core_layout.size);
-
-	/* Put string table section at end of init part of module. */
-	strsect->sh_flags |= SHF_ALLOC;
-	strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect,
-					 info->index.str) | INIT_OFFSET_MASK;
-	pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
-
-	/* We'll tack temporary mod_kallsyms on the end. */
-	mod->init_layout.size = ALIGN(mod->init_layout.size,
-				      __alignof__(struct mod_kallsyms));
-	info->mod_kallsyms_init_off = mod->init_layout.size;
-	mod->init_layout.size += sizeof(struct mod_kallsyms);
-	info->init_typeoffs = mod->init_layout.size;
-	mod->init_layout.size += nsrc * sizeof(char);
-	mod->init_layout.size = debug_align(mod->init_layout.size);
-}
-
-/*
- * We use the full symtab and strtab which layout_symtab arranged to
- * be appended to the init section.  Later we switch to the cut-down
- * core-only ones.
- */
-static void add_kallsyms(struct module *mod, const struct load_info *info)
-{
-	unsigned int i, ndst;
-	const Elf_Sym *src;
-	Elf_Sym *dst;
-	char *s;
-	Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
-
-	/* Set up to point into init section. */
-	mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off;
-
-	mod->kallsyms->symtab = (void *)symsec->sh_addr;
-	mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
-	/* Make sure we get permanent strtab: don't use info->strtab. */
-	mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
-	mod->kallsyms->typetab = mod->init_layout.base + info->init_typeoffs;
-
-	/*
-	 * Now populate the cut down core kallsyms for after init
-	 * and set types up while we still have access to sections.
-	 */
-	mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs;
-	mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs;
-	mod->core_kallsyms.typetab = mod->core_layout.base + info->core_typeoffs;
-	src = mod->kallsyms->symtab;
-	for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) {
-		mod->kallsyms->typetab[i] = elf_type(src + i, info);
-		if (i == 0 || is_livepatch_module(mod) ||
-		    is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
-				   info->index.pcpu)) {
-			mod->core_kallsyms.typetab[ndst] =
-			    mod->kallsyms->typetab[i];
-			dst[ndst] = src[i];
-			dst[ndst++].st_name = s - mod->core_kallsyms.strtab;
-			s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name],
-				     KSYM_NAME_LEN) + 1;
-		}
-	}
-	mod->core_kallsyms.num_symtab = ndst;
-}
-#else
-static inline void layout_symtab(struct module *mod, struct load_info *info)
-{
-}
-
-static void add_kallsyms(struct module *mod, const struct load_info *info)
-{
-}
-#endif /* CONFIG_KALLSYMS */
-
-#if IS_ENABLED(CONFIG_KALLSYMS) && IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
-static void init_build_id(struct module *mod, const struct load_info *info)
-{
-	const Elf_Shdr *sechdr;
-	unsigned int i;
-
-	for (i = 0; i < info->hdr->e_shnum; i++) {
-		sechdr = &info->sechdrs[i];
-		if (!sect_empty(sechdr) && sechdr->sh_type == SHT_NOTE &&
-		    !build_id_parse_buf((void *)sechdr->sh_addr, mod->build_id,
-					sechdr->sh_size))
-			break;
-	}
-}
-#else
-static void init_build_id(struct module *mod, const struct load_info *info)
-{
-}
-#endif
-
 static void dynamic_debug_setup(struct module *mod, struct _ddebug *debug, unsigned int num)
 {
 	if (!debug)
@@ -3761,285 +3532,6 @@ static inline int within(unsigned long addr, void *start, unsigned long size)
 	return ((void *)addr >= start && (void *)addr < start + size);
 }
 
-#ifdef CONFIG_KALLSYMS
-/*
- * This ignores the intensely annoying "mapping symbols" found
- * in ARM ELF files: $a, $t and $d.
- */
-static inline int is_arm_mapping_symbol(const char *str)
-{
-	if (str[0] == '.' && str[1] == 'L')
-		return true;
-	return str[0] == '$' && strchr("axtd", str[1])
-	       && (str[2] == '\0' || str[2] == '.');
-}
-
-static const char *kallsyms_symbol_name(struct mod_kallsyms *kallsyms, unsigned int symnum)
-{
-	return kallsyms->strtab + kallsyms->symtab[symnum].st_name;
-}
-
-/*
- * Given a module and address, find the corresponding symbol and return its name
- * while providing its size and offset if needed.
- */
-static const char *find_kallsyms_symbol(struct module *mod,
-					unsigned long addr,
-					unsigned long *size,
-					unsigned long *offset)
-{
-	unsigned int i, best = 0;
-	unsigned long nextval, bestval;
-	struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
-
-	/* At worse, next value is at end of module */
-	if (within_module_init(addr, mod))
-		nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size;
-	else
-		nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size;
-
-	bestval = kallsyms_symbol_value(&kallsyms->symtab[best]);
-
-	/*
-	 * Scan for closest preceding symbol, and next symbol. (ELF
-	 * starts real symbols at 1).
-	 */
-	for (i = 1; i < kallsyms->num_symtab; i++) {
-		const Elf_Sym *sym = &kallsyms->symtab[i];
-		unsigned long thisval = kallsyms_symbol_value(sym);
-
-		if (sym->st_shndx == SHN_UNDEF)
-			continue;
-
-		/*
-		 * We ignore unnamed symbols: they're uninformative
-		 * and inserted at a whim.
-		 */
-		if (*kallsyms_symbol_name(kallsyms, i) == '\0'
-		    || is_arm_mapping_symbol(kallsyms_symbol_name(kallsyms, i)))
-			continue;
-
-		if (thisval <= addr && thisval > bestval) {
-			best = i;
-			bestval = thisval;
-		}
-		if (thisval > addr && thisval < nextval)
-			nextval = thisval;
-	}
-
-	if (!best)
-		return NULL;
-
-	if (size)
-		*size = nextval - bestval;
-	if (offset)
-		*offset = addr - bestval;
-
-	return kallsyms_symbol_name(kallsyms, best);
-}
-
-void * __weak dereference_module_function_descriptor(struct module *mod,
-						     void *ptr)
-{
-	return ptr;
-}
-
-/*
- * For kallsyms to ask for address resolution.  NULL means not found.  Careful
- * not to lock to avoid deadlock on oopses, simply disable preemption.
- */
-const char *module_address_lookup(unsigned long addr,
-			    unsigned long *size,
-			    unsigned long *offset,
-			    char **modname,
-			    const unsigned char **modbuildid,
-			    char *namebuf)
-{
-	const char *ret = NULL;
-	struct module *mod;
-
-	preempt_disable();
-	mod = __module_address(addr);
-	if (mod) {
-		if (modname)
-			*modname = mod->name;
-		if (modbuildid) {
-#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID)
-			*modbuildid = mod->build_id;
-#else
-			*modbuildid = NULL;
-#endif
-		}
-
-		ret = find_kallsyms_symbol(mod, addr, size, offset);
-	}
-	/* Make a copy in here where it's safe */
-	if (ret) {
-		strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
-		ret = namebuf;
-	}
-	preempt_enable();
-
-	return ret;
-}
-
-int lookup_module_symbol_name(unsigned long addr, char *symname)
-{
-	struct module *mod;
-
-	preempt_disable();
-	list_for_each_entry_rcu(mod, &modules, list) {
-		if (mod->state == MODULE_STATE_UNFORMED)
-			continue;
-		if (within_module(addr, mod)) {
-			const char *sym;
-
-			sym = find_kallsyms_symbol(mod, addr, NULL, NULL);
-			if (!sym)
-				goto out;
-
-			strlcpy(symname, sym, KSYM_NAME_LEN);
-			preempt_enable();
-			return 0;
-		}
-	}
-out:
-	preempt_enable();
-	return -ERANGE;
-}
-
-int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
-			unsigned long *offset, char *modname, char *name)
-{
-	struct module *mod;
-
-	preempt_disable();
-	list_for_each_entry_rcu(mod, &modules, list) {
-		if (mod->state == MODULE_STATE_UNFORMED)
-			continue;
-		if (within_module(addr, mod)) {
-			const char *sym;
-
-			sym = find_kallsyms_symbol(mod, addr, size, offset);
-			if (!sym)
-				goto out;
-			if (modname)
-				strlcpy(modname, mod->name, MODULE_NAME_LEN);
-			if (name)
-				strlcpy(name, sym, KSYM_NAME_LEN);
-			preempt_enable();
-			return 0;
-		}
-	}
-out:
-	preempt_enable();
-	return -ERANGE;
-}
-
-int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
-			char *name, char *module_name, int *exported)
-{
-	struct module *mod;
-
-	preempt_disable();
-	list_for_each_entry_rcu(mod, &modules, list) {
-		struct mod_kallsyms *kallsyms;
-
-		if (mod->state == MODULE_STATE_UNFORMED)
-			continue;
-		kallsyms = rcu_dereference_sched(mod->kallsyms);
-		if (symnum < kallsyms->num_symtab) {
-			const Elf_Sym *sym = &kallsyms->symtab[symnum];
-
-			*value = kallsyms_symbol_value(sym);
-			*type = kallsyms->typetab[symnum];
-			strlcpy(name, kallsyms_symbol_name(kallsyms, symnum), KSYM_NAME_LEN);
-			strlcpy(module_name, mod->name, MODULE_NAME_LEN);
-			*exported = is_exported(name, *value, mod);
-			preempt_enable();
-			return 0;
-		}
-		symnum -= kallsyms->num_symtab;
-	}
-	preempt_enable();
-	return -ERANGE;
-}
-
-/* Given a module and name of symbol, find and return the symbol's value */
-static unsigned long find_kallsyms_symbol_value(struct module *mod, const char *name)
-{
-	unsigned int i;
-	struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
-
-	for (i = 0; i < kallsyms->num_symtab; i++) {
-		const Elf_Sym *sym = &kallsyms->symtab[i];
-
-		if (strcmp(name, kallsyms_symbol_name(kallsyms, i)) == 0 &&
-		    sym->st_shndx != SHN_UNDEF)
-			return kallsyms_symbol_value(sym);
-	}
-	return 0;
-}
-
-/* Look for this name: can be of form module:name. */
-unsigned long module_kallsyms_lookup_name(const char *name)
-{
-	struct module *mod;
-	char *colon;
-	unsigned long ret = 0;
-
-	/* Don't lock: we're in enough trouble already. */
-	preempt_disable();
-	if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) {
-		if ((mod = find_module_all(name, colon - name, false)) != NULL)
-			ret = find_kallsyms_symbol_value(mod, colon+1);
-	} else {
-		list_for_each_entry_rcu(mod, &modules, list) {
-			if (mod->state == MODULE_STATE_UNFORMED)
-				continue;
-			if ((ret = find_kallsyms_symbol_value(mod, name)) != 0)
-				break;
-		}
-	}
-	preempt_enable();
-	return ret;
-}
-
-#ifdef CONFIG_LIVEPATCH
-int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
-					     struct module *, unsigned long),
-				   void *data)
-{
-	struct module *mod;
-	unsigned int i;
-	int ret = 0;
-
-	mutex_lock(&module_mutex);
-	list_for_each_entry(mod, &modules, list) {
-		/* We hold module_mutex: no need for rcu_dereference_sched */
-		struct mod_kallsyms *kallsyms = mod->kallsyms;
-
-		if (mod->state == MODULE_STATE_UNFORMED)
-			continue;
-		for (i = 0; i < kallsyms->num_symtab; i++) {
-			const Elf_Sym *sym = &kallsyms->symtab[i];
-
-			if (sym->st_shndx == SHN_UNDEF)
-				continue;
-
-			ret = fn(data, kallsyms_symbol_name(kallsyms, i),
-				 mod, kallsyms_symbol_value(sym));
-			if (ret != 0)
-				goto out;
-		}
-	}
-out:
-	mutex_unlock(&module_mutex);
-	return ret;
-}
-#endif /* CONFIG_LIVEPATCH */
-#endif /* CONFIG_KALLSYMS */
-
 static void cfi_init(struct module *mod)
 {
 #ifdef CONFIG_CFI_CLANG
-- 
2.34.1

[RFC PATCH v3 10/13] module: Move procfs support into a separate file

[Aaron Tomlin]

No functional change.

This patch migrates code that allows one to generate a
list of loaded/or linked modules via /proc when procfs
support is enabled into kernel/module/procfs.c.

Signed-off-by: Aaron Tomlin <atomlin@redhat.com>
---
 kernel/module/Makefile   |   1 +
 kernel/module/internal.h |   1 +
 kernel/module/main.c     | 131 +-----------------------------------
 kernel/module/procfs.c   | 142 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 145 insertions(+), 130 deletions(-)
 create mode 100644 kernel/module/procfs.c

diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index 5fb2a7fec743..f821903e2c5d 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -13,3 +13,4 @@ obj-$(CONFIG_ARCH_HAS_STRICT_MODULE_RWX) += arch_strict_rwx.o
 obj-$(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
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index e69d0249df6b..a067107c97bc 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -62,6 +62,7 @@ extern unsigned long kernel_symbol_value(const struct kernel_symbol *sym);
 extern int cmp_name(const void *name, const void *sym);
 extern long get_offset(struct module *mod, unsigned int *size, Elf_Shdr *sechdr,
 		       unsigned int section);
+extern char *module_flags(struct module *mod, char *buf);
 
 #ifdef CONFIG_LIVEPATCH
 extern int copy_module_elf(struct module *mod, struct load_info *info);
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 054f34de4e6c..78389be0eb5f 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -21,7 +21,6 @@
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
 #include <linux/elf.h>
-#include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/syscalls.h>
 #include <linux/fcntl.h>
@@ -801,31 +800,6 @@ SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
 	return ret;
 }
 
-static inline void print_unload_info(struct seq_file *m, struct module *mod)
-{
-	struct module_use *use;
-	int printed_something = 0;
-
-	seq_printf(m, " %i ", module_refcount(mod));
-
-	/*
-	 * Always include a trailing , so userspace can differentiate
-	 * between this and the old multi-field proc format.
-	 */
-	list_for_each_entry(use, &mod->source_list, source_list) {
-		printed_something = 1;
-		seq_printf(m, "%s,", use->source->name);
-	}
-
-	if (mod->init != NULL && mod->exit == NULL) {
-		printed_something = 1;
-		seq_puts(m, "[permanent],");
-	}
-
-	if (!printed_something)
-		seq_puts(m, "-");
-}
-
 void __symbol_put(const char *symbol)
 {
 	struct find_symbol_arg fsa = {
@@ -915,12 +889,6 @@ void module_put(struct module *module)
 EXPORT_SYMBOL(module_put);
 
 #else /* !CONFIG_MODULE_UNLOAD */
-static inline void print_unload_info(struct seq_file *m, struct module *mod)
-{
-	/* We don't know the usage count, or what modules are using. */
-	seq_puts(m, " - -");
-}
-
 static inline void module_unload_free(struct module *mod)
 {
 }
@@ -3567,7 +3535,7 @@ static void cfi_cleanup(struct module *mod)
 }
 
 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
-static char *module_flags(struct module *mod, char *buf)
+char *module_flags(struct module *mod, char *buf)
 {
 	int bx = 0;
 
@@ -3590,103 +3558,6 @@ static char *module_flags(struct module *mod, char *buf)
 	return buf;
 }
 
-#ifdef CONFIG_PROC_FS
-/* Called by the /proc file system to return a list of modules. */
-static void *m_start(struct seq_file *m, loff_t *pos)
-{
-	mutex_lock(&module_mutex);
-	return seq_list_start(&modules, *pos);
-}
-
-static void *m_next(struct seq_file *m, void *p, loff_t *pos)
-{
-	return seq_list_next(p, &modules, pos);
-}
-
-static void m_stop(struct seq_file *m, void *p)
-{
-	mutex_unlock(&module_mutex);
-}
-
-static int m_show(struct seq_file *m, void *p)
-{
-	struct module *mod = list_entry(p, struct module, list);
-	char buf[MODULE_FLAGS_BUF_SIZE];
-	void *value;
-
-	/* We always ignore unformed modules. */
-	if (mod->state == MODULE_STATE_UNFORMED)
-		return 0;
-
-	seq_printf(m, "%s %u",
-		   mod->name, mod->init_layout.size + mod->core_layout.size);
-	print_unload_info(m, mod);
-
-	/* Informative for users. */
-	seq_printf(m, " %s",
-		   mod->state == MODULE_STATE_GOING ? "Unloading" :
-		   mod->state == MODULE_STATE_COMING ? "Loading" :
-		   "Live");
-	/* Used by oprofile and other similar tools. */
-	value = m->private ? NULL : mod->core_layout.base;
-	seq_printf(m, " 0x%px", value);
-
-	/* Taints info */
-	if (mod->taints)
-		seq_printf(m, " %s", module_flags(mod, buf));
-
-	seq_puts(m, "\n");
-	return 0;
-}
-
-/*
- * Format: modulename size refcount deps address
- *
- * Where refcount is a number or -, and deps is a comma-separated list
- * of depends or -.
- */
-static const struct seq_operations modules_op = {
-	.start	= m_start,
-	.next	= m_next,
-	.stop	= m_stop,
-	.show	= m_show
-};
-
-/*
- * This also sets the "private" pointer to non-NULL if the
- * kernel pointers should be hidden (so you can just test
- * "m->private" to see if you should keep the values private).
- *
- * We use the same logic as for /proc/kallsyms.
- */
-static int modules_open(struct inode *inode, struct file *file)
-{
-	int err = seq_open(file, &modules_op);
-
-	if (!err) {
-		struct seq_file *m = file->private_data;
-		m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul;
-	}
-
-	return err;
-}
-
-static const struct proc_ops modules_proc_ops = {
-	.proc_flags	= PROC_ENTRY_PERMANENT,
-	.proc_open	= modules_open,
-	.proc_read	= seq_read,
-	.proc_lseek	= seq_lseek,
-	.proc_release	= seq_release,
-};
-
-static int __init proc_modules_init(void)
-{
-	proc_create("modules", 0, NULL, &modules_proc_ops);
-	return 0;
-}
-module_init(proc_modules_init);
-#endif
-
 /* Given an address, look for it in the module exception tables. */
 const struct exception_table_entry *search_module_extables(unsigned long addr)
 {
diff --git a/kernel/module/procfs.c b/kernel/module/procfs.c
new file mode 100644
index 000000000000..d706a798b52e
--- /dev/null
+++ b/kernel/module/procfs.c
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Module proc support
+ *
+ * Copyright (C) 2008 Alexey Dobriyan
+ */
+
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/mutex.h>
+#include <linux/seq_file.h>
+#include <linux/proc_fs.h>
+#include "internal.h"
+
+#ifdef CONFIG_MODULE_UNLOAD
+static inline void print_unload_info(struct seq_file *m, struct module *mod)
+{
+	struct module_use *use;
+	int printed_something = 0;
+
+	seq_printf(m, " %i ", module_refcount(mod));
+
+	/*
+	 * Always include a trailing , so userspace can differentiate
+	 * between this and the old multi-field proc format.
+	 */
+	list_for_each_entry(use, &mod->source_list, source_list) {
+		printed_something = 1;
+		seq_printf(m, "%s,", use->source->name);
+	}
+
+	if (mod->init != NULL && mod->exit == NULL) {
+		printed_something = 1;
+		seq_puts(m, "[permanent],");
+	}
+
+	if (!printed_something)
+		seq_puts(m, "-");
+}
+#else /* !CONFIG_MODULE_UNLOAD */
+static inline void print_unload_info(struct seq_file *m, struct module *mod)
+{
+	/* We don't know the usage count, or what modules are using. */
+	seq_puts(m, " - -");
+}
+#endif /* CONFIG_MODULE_UNLOAD */
+
+/* Called by the /proc file system to return a list of modules. */
+static void *m_start(struct seq_file *m, loff_t *pos)
+{
+	mutex_lock(&module_mutex);
+	return seq_list_start(&modules, *pos);
+}
+
+static void *m_next(struct seq_file *m, void *p, loff_t *pos)
+{
+	return seq_list_next(p, &modules, pos);
+}
+
+static void m_stop(struct seq_file *m, void *p)
+{
+	mutex_unlock(&module_mutex);
+}
+
+static int m_show(struct seq_file *m, void *p)
+{
+	struct module *mod = list_entry(p, struct module, list);
+	char buf[MODULE_FLAGS_BUF_SIZE];
+	void *value;
+
+	/* We always ignore unformed modules. */
+	if (mod->state == MODULE_STATE_UNFORMED)
+		return 0;
+
+	seq_printf(m, "%s %u",
+		   mod->name, mod->init_layout.size + mod->core_layout.size);
+	print_unload_info(m, mod);
+
+	/* Informative for users. */
+	seq_printf(m, " %s",
+		   mod->state == MODULE_STATE_GOING ? "Unloading" :
+		   mod->state == MODULE_STATE_COMING ? "Loading" :
+		   "Live");
+	/* Used by oprofile and other similar tools. */
+	value = m->private ? NULL : mod->core_layout.base;
+	seq_printf(m, " 0x%px", value);
+
+	/* Taints info */
+	if (mod->taints)
+		seq_printf(m, " %s", module_flags(mod, buf));
+
+	seq_puts(m, "\n");
+	return 0;
+}
+
+/*
+ * Format: modulename size refcount deps address
+ *
+ * Where refcount is a number or -, and deps is a comma-separated list
+ * of depends or -.
+ */
+static const struct seq_operations modules_op = {
+	.start	= m_start,
+	.next	= m_next,
+	.stop	= m_stop,
+	.show	= m_show
+};
+
+/*
+ * This also sets the "private" pointer to non-NULL if the
+ * kernel pointers should be hidden (so you can just test
+ * "m->private" to see if you should keep the values private).
+ *
+ * We use the same logic as for /proc/kallsyms.
+ */
+static int modules_open(struct inode *inode, struct file *file)
+{
+	int err = seq_open(file, &modules_op);
+
+	if (!err) {
+		struct seq_file *m = file->private_data;
+
+		m->private = kallsyms_show_value(file->f_cred) ? NULL : (void *)8ul;
+	}
+
+	return err;
+}
+
+static const struct proc_ops modules_proc_ops = {
+	.proc_flags	= PROC_ENTRY_PERMANENT,
+	.proc_open	= modules_open,
+	.proc_read	= seq_read,
+	.proc_lseek	= seq_lseek,
+	.proc_release	= seq_release,
+};
+
+static int __init proc_modules_init(void)
+{
+	proc_create("modules", 0, NULL, &modules_proc_ops);
+	return 0;
+}
+module_init(proc_modules_init);
-- 
2.34.1

[RFC PATCH v3 11/13] module: Move sysfs support into a separate file

[Aaron Tomlin]

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 <atomlin@redhat.com>
---
 kernel/module/Makefile   |   1 +
 kernel/module/internal.h |  24 ++
 kernel/module/main.c     | 458 +--------------------------------------
 kernel/module/sysfs.c    | 425 ++++++++++++++++++++++++++++++++++++
 4 files changed, 453 insertions(+), 455 deletions(-)
 create mode 100644 kernel/module/sysfs.c

diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index f821903e2c5d..44b9b4924d71 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -14,3 +14,4 @@ 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
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index a067107c97bc..bf2746949e93 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -23,6 +23,9 @@
 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[];
@@ -125,3 +128,24 @@ static inline char *find_kallsyms_symbol(struct module *mod, unsigned long addr,
 	return NULL;
 }
 #endif /* CONFIG_KALLSYMS */
+
+#ifdef CONFIG_SYSFS
+extern int mod_sysfs_setup(struct module *mod, const struct load_info *info,
+			   struct kernel_param *kparam, unsigned int num_params);
+extern void mod_sysfs_fini(struct module *mod);
+extern void module_remove_modinfo_attrs(struct module *mod, int end);
+extern void del_usage_links(struct module *mod);
+extern void init_param_lock(struct module *mod);
+#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 inline void mod_sysfs_fini(struct module *mod) { }
+static inline void module_remove_modinfo_attrs(struct module *mod, int end) { }
+static inline void del_usage_links(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 78389be0eb5f..574cba3e0418 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -13,9 +13,7 @@
 #include <linux/trace_events.h>
 #include <linux/init.h>
 #include <linux/kallsyms.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>
@@ -985,7 +983,7 @@ 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,
@@ -999,6 +997,8 @@ 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)
@@ -1249,458 +1249,6 @@ resolve_symbol_wait(struct module *mod,
 	return ksym;
 }
 
-/*
- * /sys/module/foo/sections stuff
- * J. Corbet <corbet@lwn.net>
- */
-#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[];
-};
-
-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);
diff --git a/kernel/module/sysfs.c b/kernel/module/sysfs.c
new file mode 100644
index 000000000000..f5c72c567e71
--- /dev/null
+++ b/kernel/module/sysfs.c
@@ -0,0 +1,425 @@
+// 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 <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[];
+};
+
+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 = 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 */
+
+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 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;
+}
+
+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;
+}
+
+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;
+}
+
+void mod_sysfs_fini(struct module *mod)
+{
+	remove_notes_attrs(mod);
+	remove_sect_attrs(mod);
+	mod_kobject_put(mod);
+}
+
+void init_param_lock(struct module *mod)
+{
+	mutex_init(&mod->param_lock);
+}
-- 
2.34.1

[RFC PATCH v3 12/13] module: Move kdb_modules list out of core code

[Aaron Tomlin]

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 <atomlin@redhat.com>
---
 kernel/debug/kdb/kdb_main.c | 5 +++++
 kernel/module/main.c        | 4 ----
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index 0852a537dad4..f101f5f078f4 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;
+struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
+#endif /* CONFIG_MODULES */
+
 /*
  * Kernel debugger state flags
  */
diff --git a/kernel/module/main.c b/kernel/module/main.c
index 574cba3e0418..1f16e67f687f 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -95,10 +95,6 @@ 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

[RFC PATCH v3 13/13] module: Move version support into a separate file

[Aaron Tomlin]

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 <atomlin@redhat.com>
---
 kernel/module/Makefile   |   1 +
 kernel/module/internal.h |  51 +++++++++++++
 kernel/module/main.c     | 150 +--------------------------------------
 kernel/module/version.c  | 110 ++++++++++++++++++++++++++++
 4 files changed, 164 insertions(+), 148 deletions(-)
 create mode 100644 kernel/module/version.c

diff --git a/kernel/module/Makefile b/kernel/module/Makefile
index 44b9b4924d71..8b88ae28e714 100644
--- a/kernel/module/Makefile
+++ b/kernel/module/Makefile
@@ -15,3 +15,4 @@ 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
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
index bf2746949e93..94c6cfddf0a2 100644
--- a/kernel/module/internal.h
+++ b/kernel/module/internal.h
@@ -59,7 +59,31 @@ struct load_info {
 	} index;
 };
 
+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;
+};
+
 extern int mod_verify_sig(const void *mod, struct load_info *info);
+extern int try_to_force_load(struct module *mod, const char *reason);
+extern bool find_symbol(struct find_symbol_arg *fsa);
 extern struct module *find_module_all(const char *name, size_t len, bool even_unformed);
 extern unsigned long kernel_symbol_value(const struct kernel_symbol *sym);
 extern int cmp_name(const void *name, const void *sym);
@@ -149,3 +173,30 @@ static inline void module_remove_modinfo_attrs(struct module *mod, int end) { }
 static inline void del_usage_links(struct module *mod) { }
 static inline void init_param_lock(struct module *mod) { }
 #endif /* CONFIG_SYSFS */
+
+#ifdef CONFIG_MODVERSIONS
+extern int check_version(const struct load_info *info,
+			 const char *symname, struct module *mod, const s32 *crc);
+extern int check_modstruct_version(const struct load_info *info, struct module *mod);
+extern 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 1f16e67f687f..0a1bd11d2a6e 100644
--- a/kernel/module/main.c
+++ b/kernel/module/main.c
@@ -231,28 +231,6 @@ 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)
@@ -323,7 +301,7 @@ 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,
@@ -997,7 +975,7 @@ 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))
@@ -1009,115 +987,6 @@ 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);
@@ -3229,18 +3098,3 @@ 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..6a2c9ae1c5c5
--- /dev/null
+++ b/kernel/module/version.c
@@ -0,0 +1,110 @@
+// 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"
+
+/*
+ * 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);
+
+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;
+}
+
+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. */
+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;
+}
-- 
2.34.1

Re: [RFC PATCH v3 00/13] module: core code clean up

[Oleksandr Natalenko]

Hello.

On pátek 28. ledna 2022 21:39:21 CET Aaron Tomlin wrote:
> Hi Luis,
> 
> [Note: Cc'd live-patching for feedback on livepatch specific changes]
> 
> Firstly, apologies for the delay.
> 
> As per your suggestion [1], this is an attempt to refactor and split
> optional code out of core module support code into separate components.
> This version is based on branch mcgrof/modules-next since a97ac8cb24a3/or
> modules-5.17-rc1. Please let me know your thoughts.
> 
> Changes since v1 [2]:
> 
>   - Moved module version support code into a new file
> 
> Changes since v2 [3]:
> 
>  - Move module decompress support to a separate file
>  - Make check_modinfo_livepatch() generic (Petr Mladek)
>  - Remove filename from each newly created file (Luis Chamberlain)
>  - Addressed some (i.e. --ignore=ASSIGN_IN_IF,AVOID_BUG was used)
>    minor scripts/checkpatch.pl concerns e.g., use strscpy over
>    strlcpy and missing a blank line after declarations (Allen)

Thanks for your submission.

Aaron, could you please also include stats from `./scripts/bloat-o-meter` to compare `vmlinux` sections size before and after your modifications?

> [1]: https://lore.kernel.org/lkml/YbEZ4HgSYQEPuRmS@bombadil.infradead.org/
> [2]: https://lore.kernel.org/lkml/20211228213041.1356334-1-atomlin@redhat.com/
> [3]: https://lore.kernel.org/lkml/20220106234319.2067842-1-atomlin@redhat.com/
> 
> 
> Aaron Tomlin (13):
>   module: Move all into module/
>   module: Simple refactor in preparation for split
>   module: Move livepatch support to a separate file
>   module: Move latched RB-tree support to a separate file
>   module: Move arch strict rwx support to a separate file
>   module: Move strict rwx support to a separate file
>   module: Move extra signature support out of core code
>   module: Move kmemleak support to a separate file
>   module: Move kallsyms support into a separate file
>   module: Move procfs support into a separate file
>   module: Move sysfs support into a separate file
>   module: Move kdb_modules list out of core code
>   module: Move version support into a separate file
> 
>  MAINTAINERS                                   |    2 +-
>  include/linux/module.h                        |   92 +-
>  kernel/Makefile                               |    5 +-
>  kernel/debug/kdb/kdb_main.c                   |    5 +
>  kernel/module-internal.h                      |   50 -
>  kernel/module/Makefile                        |   18 +
>  kernel/module/arch_strict_rwx.c               |   44 +
>  kernel/module/debug_kmemleak.c                |   30 +
>  .../decompress.c}                             |    2 +-
>  kernel/module/internal.h                      |  202 ++
>  kernel/module/kallsyms.c                      |  502 +++++
>  kernel/module/livepatch.c                     |   74 +
>  kernel/{module.c => module/main.c}            | 1879 +----------------
>  kernel/module/procfs.c                        |  142 ++
>  .../signature.c}                              |    0
>  kernel/module/signing.c                       |  120 ++
>  kernel/module/strict_rwx.c                    |   83 +
>  kernel/module/sysfs.c                         |  425 ++++
>  kernel/module/tree_lookup.c                   |  108 +
>  kernel/module/version.c                       |  110 +
>  kernel/module_signing.c                       |   45 -
>  21 files changed, 2032 insertions(+), 1906 deletions(-)
>  delete mode 100644 kernel/module-internal.h
>  create mode 100644 kernel/module/Makefile
>  create mode 100644 kernel/module/arch_strict_rwx.c
>  create mode 100644 kernel/module/debug_kmemleak.c
>  rename kernel/{module_decompress.c => module/decompress.c} (99%)
>  create mode 100644 kernel/module/internal.h
>  create mode 100644 kernel/module/kallsyms.c
>  create mode 100644 kernel/module/livepatch.c
>  rename kernel/{module.c => module/main.c} (63%)
>  create mode 100644 kernel/module/procfs.c
>  rename kernel/{module_signature.c => module/signature.c} (100%)
>  create mode 100644 kernel/module/signing.c
>  create mode 100644 kernel/module/strict_rwx.c
>  create mode 100644 kernel/module/sysfs.c
>  create mode 100644 kernel/module/tree_lookup.c
>  create mode 100644 kernel/module/version.c
>  delete mode 100644 kernel/module_signing.c
> 
> 
> base-commit: a97ac8cb24a3c3ad74794adb83717ef1605d1b47
> 


-- 
Oleksandr Natalenko (post-factum)