summaryrefslogtreecommitdiff
path: root/kernel/module
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/module')
-rw-r--r--kernel/module/Makefile12
-rw-r--r--kernel/module/decompress.c273
-rw-r--r--kernel/module/internal.h50
-rw-r--r--kernel/module/main.c4810
-rw-r--r--kernel/module/signing.c45
5 files changed, 5190 insertions, 0 deletions
diff --git a/kernel/module/Makefile b/kernel/module/Makefile
new file mode 100644
index 000000000000..cdd5c61b8c7f
--- /dev/null
+++ b/kernel/module/Makefile
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for linux kernel module support
+#
+
+# These are called from save_stack_trace() on slub debug path,
+# and produce insane amounts of uninteresting coverage.
+KCOV_INSTRUMENT_module.o := n
+
+obj-y += main.o
+obj-$(CONFIG_MODULE_DECOMPRESS) += decompress.o
+obj-$(CONFIG_MODULE_SIG) += signing.o
diff --git a/kernel/module/decompress.c b/kernel/module/decompress.c
new file mode 100644
index 000000000000..d14d6443225a
--- /dev/null
+++ b/kernel/module/decompress.c
@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2021 Google LLC.
+ */
+
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/kobject.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/vmalloc.h>
+
+#include "internal.h"
+
+static int module_extend_max_pages(struct load_info *info, unsigned int extent)
+{
+ struct page **new_pages;
+
+ new_pages = kvmalloc_array(info->max_pages + extent,
+ sizeof(info->pages), GFP_KERNEL);
+ if (!new_pages)
+ return -ENOMEM;
+
+ memcpy(new_pages, info->pages, info->max_pages * sizeof(info->pages));
+ kvfree(info->pages);
+ info->pages = new_pages;
+ info->max_pages += extent;
+
+ return 0;
+}
+
+static struct page *module_get_next_page(struct load_info *info)
+{
+ struct page *page;
+ int error;
+
+ if (info->max_pages == info->used_pages) {
+ error = module_extend_max_pages(info, info->used_pages);
+ if (error)
+ return ERR_PTR(error);
+ }
+
+ page = alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
+ if (!page)
+ return ERR_PTR(-ENOMEM);
+
+ info->pages[info->used_pages++] = page;
+ return page;
+}
+
+#ifdef CONFIG_MODULE_COMPRESS_GZIP
+#include <linux/zlib.h>
+#define MODULE_COMPRESSION gzip
+#define MODULE_DECOMPRESS_FN module_gzip_decompress
+
+/*
+ * Calculate length of the header which consists of signature, header
+ * flags, time stamp and operating system ID (10 bytes total), plus
+ * an optional filename.
+ */
+static size_t module_gzip_header_len(const u8 *buf, size_t size)
+{
+ const u8 signature[] = { 0x1f, 0x8b, 0x08 };
+ size_t len = 10;
+
+ if (size < len || memcmp(buf, signature, sizeof(signature)))
+ return 0;
+
+ if (buf[3] & 0x08) {
+ do {
+ /*
+ * If we can't find the end of the file name we must
+ * be dealing with a corrupted file.
+ */
+ if (len == size)
+ return 0;
+ } while (buf[len++] != '\0');
+ }
+
+ return len;
+}
+
+static ssize_t module_gzip_decompress(struct load_info *info,
+ const void *buf, size_t size)
+{
+ struct z_stream_s s = { 0 };
+ size_t new_size = 0;
+ size_t gzip_hdr_len;
+ ssize_t retval;
+ int rc;
+
+ gzip_hdr_len = module_gzip_header_len(buf, size);
+ if (!gzip_hdr_len) {
+ pr_err("not a gzip compressed module\n");
+ return -EINVAL;
+ }
+
+ s.next_in = buf + gzip_hdr_len;
+ s.avail_in = size - gzip_hdr_len;
+
+ s.workspace = kmalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
+ if (!s.workspace)
+ return -ENOMEM;
+
+ rc = zlib_inflateInit2(&s, -MAX_WBITS);
+ if (rc != Z_OK) {
+ pr_err("failed to initialize decompressor: %d\n", rc);
+ retval = -EINVAL;
+ goto out;
+ }
+
+ do {
+ struct page *page = module_get_next_page(info);
+ if (!page) {
+ retval = -ENOMEM;
+ goto out_inflate_end;
+ }
+
+ s.next_out = kmap(page);
+ s.avail_out = PAGE_SIZE;
+ rc = zlib_inflate(&s, 0);
+ kunmap(page);
+
+ new_size += PAGE_SIZE - s.avail_out;
+ } while (rc == Z_OK);
+
+ if (rc != Z_STREAM_END) {
+ pr_err("decompression failed with status %d\n", rc);
+ retval = -EINVAL;
+ goto out_inflate_end;
+ }
+
+ retval = new_size;
+
+out_inflate_end:
+ zlib_inflateEnd(&s);
+out:
+ kfree(s.workspace);
+ return retval;
+}
+#elif CONFIG_MODULE_COMPRESS_XZ
+#include <linux/xz.h>
+#define MODULE_COMPRESSION xz
+#define MODULE_DECOMPRESS_FN module_xz_decompress
+
+static ssize_t module_xz_decompress(struct load_info *info,
+ const void *buf, size_t size)
+{
+ static const u8 signature[] = { 0xfd, '7', 'z', 'X', 'Z', 0 };
+ struct xz_dec *xz_dec;
+ struct xz_buf xz_buf;
+ enum xz_ret xz_ret;
+ size_t new_size = 0;
+ ssize_t retval;
+
+ if (size < sizeof(signature) ||
+ memcmp(buf, signature, sizeof(signature))) {
+ pr_err("not an xz compressed module\n");
+ return -EINVAL;
+ }
+
+ xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
+ if (!xz_dec)
+ return -ENOMEM;
+
+ xz_buf.in_size = size;
+ xz_buf.in = buf;
+ xz_buf.in_pos = 0;
+
+ do {
+ struct page *page = module_get_next_page(info);
+ if (!page) {
+ retval = -ENOMEM;
+ goto out;
+ }
+
+ xz_buf.out = kmap(page);
+ xz_buf.out_pos = 0;
+ xz_buf.out_size = PAGE_SIZE;
+ xz_ret = xz_dec_run(xz_dec, &xz_buf);
+ kunmap(page);
+
+ new_size += xz_buf.out_pos;
+ } while (xz_buf.out_pos == PAGE_SIZE && xz_ret == XZ_OK);
+
+ if (xz_ret != XZ_STREAM_END) {
+ pr_err("decompression failed with status %d\n", xz_ret);
+ retval = -EINVAL;
+ goto out;
+ }
+
+ retval = new_size;
+
+ out:
+ xz_dec_end(xz_dec);
+ return retval;
+}
+#else
+#error "Unexpected configuration for CONFIG_MODULE_DECOMPRESS"
+#endif
+
+int module_decompress(struct load_info *info, const void *buf, size_t size)
+{
+ unsigned int n_pages;
+ ssize_t data_size;
+ int error;
+
+ /*
+ * Start with number of pages twice as big as needed for
+ * compressed data.
+ */
+ n_pages = DIV_ROUND_UP(size, PAGE_SIZE) * 2;
+ error = module_extend_max_pages(info, n_pages);
+
+ data_size = MODULE_DECOMPRESS_FN(info, buf, size);
+ if (data_size < 0) {
+ error = data_size;
+ goto err;
+ }
+
+ info->hdr = vmap(info->pages, info->used_pages, VM_MAP, PAGE_KERNEL);
+ if (!info->hdr) {
+ error = -ENOMEM;
+ goto err;
+ }
+
+ info->len = data_size;
+ return 0;
+
+err:
+ module_decompress_cleanup(info);
+ return error;
+}
+
+void module_decompress_cleanup(struct load_info *info)
+{
+ int i;
+
+ if (info->hdr)
+ vunmap(info->hdr);
+
+ for (i = 0; i < info->used_pages; i++)
+ __free_page(info->pages[i]);
+
+ kvfree(info->pages);
+
+ info->pages = NULL;
+ info->max_pages = info->used_pages = 0;
+}
+
+#ifdef CONFIG_SYSFS
+static ssize_t compression_show(struct kobject *kobj,
+ struct kobj_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%s\n", __stringify(MODULE_COMPRESSION));
+}
+static struct kobj_attribute module_compression_attr = __ATTR_RO(compression);
+
+static int __init module_decompress_sysfs_init(void)
+{
+ int error;
+
+ error = sysfs_create_file(&module_kset->kobj,
+ &module_compression_attr.attr);
+ if (error)
+ pr_warn("Failed to create 'compression' attribute");
+
+ return 0;
+}
+late_initcall(module_decompress_sysfs_init);
+#endif
diff --git a/kernel/module/internal.h b/kernel/module/internal.h
new file mode 100644
index 000000000000..8c381c99062f
--- /dev/null
+++ b/kernel/module/internal.h
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/* Module internals
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#include <linux/elf.h>
+#include <asm/module.h>
+
+struct load_info {
+ const char *name;
+ /* pointer to module in temporary copy, freed at end of load_module() */
+ struct module *mod;
+ Elf_Ehdr *hdr;
+ unsigned long len;
+ Elf_Shdr *sechdrs;
+ char *secstrings, *strtab;
+ unsigned long symoffs, stroffs, init_typeoffs, core_typeoffs;
+ struct _ddebug *debug;
+ unsigned int num_debug;
+ bool sig_ok;
+#ifdef CONFIG_KALLSYMS
+ unsigned long mod_kallsyms_init_off;
+#endif
+#ifdef CONFIG_MODULE_DECOMPRESS
+ struct page **pages;
+ unsigned int max_pages;
+ unsigned int used_pages;
+#endif
+ struct {
+ unsigned int sym, str, mod, vers, info, pcpu;
+ } index;
+};
+
+extern int mod_verify_sig(const void *mod, struct load_info *info);
+
+#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);
+#else
+static inline int module_decompress(struct load_info *info,
+ const void *buf, size_t size)
+{
+ return -EOPNOTSUPP;
+}
+static inline void module_decompress_cleanup(struct load_info *info)
+{
+}
+#endif
diff --git a/kernel/module/main.c b/kernel/module/main.c
new file mode 100644
index 000000000000..1a17f02f69a0
--- /dev/null
+++ b/kernel/module/main.c
@@ -0,0 +1,4810 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2002 Richard Henderson
+ * Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
+ */
+
+#define INCLUDE_VERMAGIC
+
+#include <linux/export.h>
+#include <linux/extable.h>
+#include <linux/moduleloader.h>
+#include <linux/module_signature.h>
+#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>
+#include <linux/kernel.h>
+#include <linux/kernel_read_file.h>
+#include <linux/slab.h>
+#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>
+#include <linux/rcupdate.h>
+#include <linux/capability.h>
+#include <linux/cpu.h>
+#include <linux/moduleparam.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/vermagic.h>
+#include <linux/notifier.h>
+#include <linux/sched.h>
+#include <linux/device.h>
+#include <linux/string.h>
+#include <linux/mutex.h>
+#include <linux/rculist.h>
+#include <linux/uaccess.h>
+#include <asm/cacheflush.h>
+#include <linux/set_memory.h>
+#include <asm/mmu_context.h>
+#include <linux/license.h>
+#include <asm/sections.h>
+#include <linux/tracepoint.h>
+#include <linux/ftrace.h>
+#include <linux/livepatch.h>
+#include <linux/async.h>
+#include <linux/percpu.h>
+#include <linux/kmemleak.h>
+#include <linux/jump_label.h>
+#include <linux/pfn.h>
+#include <linux/bsearch.h>
+#include <linux/dynamic_debug.h>
+#include <linux/audit.h>
+#include <uapi/linux/module.h>
+#include "internal.h"
+
+#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
+ * 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
+
+/* 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),
+ * 2) module_use links,
+ * 3) module_addr_min/module_addr_max.
+ * (delete and add uses RCU list operations).
+ */
+static DEFINE_MUTEX(module_mutex);
+static LIST_HEAD(modules);
+
+/* Work queue for freeing init sections in success case */
+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.
+ */
+static void __mod_update_bounds(void *base, unsigned int size)
+{
+ unsigned long min = (unsigned long)base;
+ unsigned long max = min + size;
+
+ if (min < module_addr_min)
+ module_addr_min = min;
+ if (max > module_addr_max)
+ module_addr_max = max;
+}
+
+static void mod_update_bounds(struct module *mod)
+{
+ __mod_update_bounds(mod->core_layout.base, mod->core_layout.size);
+ if (mod->init_layout.size)
+ __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
+ if (unlikely(!debug_locks))
+ return;
+
+ WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
+ !lockdep_is_held(&module_mutex));
+#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);
+
+/* Waiting for a module to finish initializing? */
+static DECLARE_WAIT_QUEUE_HEAD(module_wq);
+
+static BLOCKING_NOTIFIER_HEAD(module_notify_list);
+
+int register_module_notifier(struct notifier_block *nb)
+{
+ return blocking_notifier_chain_register(&module_notify_list, nb);
+}
+EXPORT_SYMBOL(register_module_notifier);
+
+int unregister_module_notifier(struct notifier_block *nb)
+{
+ return blocking_notifier_chain_unregister(&module_notify_list, nb);
+}
+EXPORT_SYMBOL(unregister_module_notifier);
+
+/*
+ * We require a truly strong try_module_get(): 0 means success.
+ * Otherwise an error is returned due to ongoing or failed
+ * initialization etc.
+ */
+static inline int strong_try_module_get(struct module *mod)
+{
+ BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
+ if (mod && mod->state == MODULE_STATE_COMING)
+ return -EBUSY;
+ if (try_module_get(mod))
+ return 0;
+ else
+ return -ENOENT;
+}
+
+static inline void add_taint_module(struct module *mod, unsigned flag,
+ enum lockdep_ok lockdep_ok)
+{
+ add_taint(flag, lockdep_ok);
+ set_bit(flag, &mod->taints);
+}
+
+/*
+ * A thread that wants to hold a reference to a module only while it
+ * is running can call this to safely exit.
+ */
+void __noreturn __module_put_and_kthread_exit(struct module *mod, long code)
+{
+ module_put(mod);
+ kthread_exit(code);
+}
+EXPORT_SYMBOL(__module_put_and_kthread_exit);
+
+/* Find a module section: 0 means not found. */
+static unsigned int find_sec(const struct load_info *info, const char *name)
+{
+ unsigned int i;
+
+ for (i = 1; i < info->hdr->e_shnum; i++) {
+ Elf_Shdr *shdr = &info->sechdrs[i];
+ /* Alloc bit cleared means "ignore it." */
+ if ((shdr->sh_flags & SHF_ALLOC)
+ && strcmp(info->secstrings + shdr->sh_name, name) == 0)
+ return i;
+ }
+ return 0;
+}
+
+/* Find a module section, or NULL. */
+static void *section_addr(const struct load_info *info, const char *name)
+{
+ /* Section 0 has sh_addr 0. */
+ return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
+}
+
+/* Find a module section, or NULL. Fill in number of "objects" in section. */
+static void *section_objs(const struct load_info *info,
+ const char *name,
+ size_t object_size,
+ unsigned int *num)
+{
+ unsigned int sec = find_sec(info, name);
+
+ /* Section 0 has sh_addr 0 and sh_size 0. */
+ *num = info->sechdrs[sec].sh_size / object_size;
+ return (void *)info->sechdrs[sec].sh_addr;
+}
+
+/* Find a module section: 0 means not found. Ignores SHF_ALLOC flag. */
+static unsigned int find_any_sec(const struct load_info *info, const char *name)
+{
+ unsigned int i;
+
+ for (i = 1; i < info->hdr->e_shnum; i++) {
+ Elf_Shdr *shdr = &info->sechdrs[i];
+ if (strcmp(info->secstrings + shdr->sh_name, name) == 0)
+ return i;
+ }
+ return 0;
+}
+
+/*
+ * Find a module section, or NULL. Fill in number of "objects" in section.
+ * Ignores SHF_ALLOC flag.
+ */
+static __maybe_unused void *any_section_objs(const struct load_info *info,
+ const char *name,
+ size_t object_size,
+ unsigned int *num)
+{
+ unsigned int sec = find_any_sec(info, name);
+
+ /* Section 0 has sh_addr 0 and sh_size 0. */
+ *num = info->sechdrs[sec].sh_size / object_size;
+ 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
+#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)
+{
+ struct find_symbol_arg *fsa = data;
+
+ if (!fsa->gplok && syms->license == GPL_ONLY)
+ return false;
+ fsa->owner = owner;
+ fsa->crc = symversion(syms->crcs, symnum);
+ fsa->sym = &syms->start[symnum];
+ fsa->license = syms->license;
+ return true;
+}
+
+static 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);
+#else
+ return sym->value;
+#endif
+}
+
+static const char *kernel_symbol_name(const struct kernel_symbol *sym)
+{
+#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
+ return offset_to_ptr(&sym->name_offset);
+#else
+ return sym->name;
+#endif
+}
+
+static const char *kernel_symbol_namespace(const struct kernel_symbol *sym)
+{
+#ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
+ if (!sym->namespace_offset)
+ return NULL;
+ return offset_to_ptr(&sym->namespace_offset);
+#else
+ return sym->namespace;
+#endif
+}
+
+static int cmp_name(const void *name, const void *sym)
+{
+ return strcmp(name, kernel_symbol_name(sym));
+}
+
+static bool find_exported_symbol_in_section(const struct symsearch *syms,
+ struct module *owner,
+ void *data)
+{
+ struct find_symbol_arg *fsa = data;
+ struct kernel_symbol *sym;
+
+ sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
+ sizeof(struct kernel_symbol), cmp_name);
+
+ if (sym != NULL && check_exported_symbol(syms, owner,
+ sym - syms->start, data))
+ return true;
+
+ return false;
+}
+
+/*
+ * 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)
+{
+ static const struct symsearch arr[] = {
+ { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
+ NOT_GPL_ONLY },
+ { __start___ksymtab_gpl, __stop___ksymtab_gpl,
+ __start___kcrctab_gpl,
+ GPL_ONLY },
+ };
+ struct module *mod;
+ unsigned int i;
+
+ module_assert_mutex_or_preempt();
+
+ for (i = 0; i < ARRAY_SIZE(arr); i++)
+ if (find_exported_symbol_in_section(&arr[i], NULL, fsa))
+ return true;
+
+ list_for_each_entry_rcu(mod, &modules, list,
+ lockdep_is_held(&module_mutex)) {
+ struct symsearch arr[] = {
+ { mod->syms, mod->syms + mod->num_syms, mod->crcs,
+ NOT_GPL_ONLY },
+ { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
+ mod->gpl_crcs,
+ GPL_ONLY },
+ };
+
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
+
+ for (i = 0; i < ARRAY_SIZE(arr); i++)
+ if (find_exported_symbol_in_section(&arr[i], mod, fsa))
+ return true;
+ }
+
+ pr_debug("Failed to find symbol %s\n", fsa->name);
+ return false;
+}
+
+/*
+ * 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,
+ bool even_unformed)
+{
+ struct module *mod;
+
+ module_assert_mutex_or_preempt();
+
+ list_for_each_entry_rcu(mod, &modules, list,
+ lockdep_is_held(&module_mutex)) {
+ if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
+ continue;
+ if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
+ return mod;
+ }
+ return NULL;
+}
+
+struct module *find_module(const char *name)
+{
+ return find_module_all(name, strlen(name), false);
+}
+
+#ifdef CONFIG_SMP
+
+static inline void __percpu *mod_percpu(struct module *mod)
+{
+ return mod->percpu;
+}
+
+static int percpu_modalloc(struct module *mod, struct load_info *info)
+{
+ Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
+ unsigned long align = pcpusec->sh_addralign;
+
+ if (!pcpusec->sh_size)
+ return 0;
+
+ if (align > PAGE_SIZE) {
+ pr_warn("%s: per-cpu alignment %li > %li\n",
+ mod->name, align, PAGE_SIZE);
+ align = PAGE_SIZE;
+ }
+
+ mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
+ if (!mod->percpu) {
+ pr_warn("%s: Could not allocate %lu bytes percpu data\n",
+ mod->name, (unsigned long)pcpusec->sh_size);
+ return -ENOMEM;
+ }
+ mod->percpu_size = pcpusec->sh_size;
+ return 0;
+}
+
+static void percpu_modfree(struct module *mod)
+{
+ free_percpu(mod->percpu);
+}
+
+static unsigned int find_pcpusec(struct load_info *info)
+{
+ return find_sec(info, ".data..percpu");
+}
+
+static void percpu_modcopy(struct module *mod,
+ const void *from, unsigned long size)
+{
+ int cpu;
+
+ for_each_possible_cpu(cpu)
+ memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
+}
+
+bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
+{
+ struct module *mod;
+ unsigned int cpu;
+
+ preempt_disable();
+
+ list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
+ if (!mod->percpu_size)
+ continue;
+ for_each_possible_cpu(cpu) {
+ void *start = per_cpu_ptr(mod->percpu, cpu);
+ void *va = (void *)addr;
+
+ if (va >= start && va < start + mod->percpu_size) {
+ if (can_addr) {
+ *can_addr = (unsigned long) (va - start);
+ *can_addr += (unsigned long)
+ per_cpu_ptr(mod->percpu,
+ get_boot_cpu_id());
+ }
+ preempt_enable();
+ return true;
+ }
+ }
+ }
+
+ preempt_enable();
+ return false;
+}
+
+/**
+ * is_module_percpu_address() - test whether address is from module static percpu
+ * @addr: address to test
+ *
+ * Test whether @addr belongs to module static percpu area.
+ *
+ * Return: %true if @addr is from module static percpu area
+ */
+bool is_module_percpu_address(unsigned long addr)
+{
+ return __is_module_percpu_address(addr, NULL);
+}
+
+#else /* ... !CONFIG_SMP */
+
+static inline void __percpu *mod_percpu(struct module *mod)
+{
+ return NULL;
+}
+static int percpu_modalloc(struct module *mod, struct load_info *info)
+{
+ /* UP modules shouldn't have this section: ENOMEM isn't quite right */
+ if (info->sechdrs[info->index.pcpu].sh_size != 0)
+ return -ENOMEM;
+ return 0;
+}
+static inline void percpu_modfree(struct module *mod)
+{
+}
+static unsigned int find_pcpusec(struct load_info *info)
+{
+ return 0;
+}
+static inline void percpu_modcopy(struct module *mod,
+ const void *from, unsigned long size)
+{
+ /* pcpusec should be 0, and size of that section should be 0. */
+ BUG_ON(size != 0);
+}
+bool is_module_percpu_address(unsigned long addr)
+{
+ return false;
+}
+
+bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
+{
+ return false;
+}
+
+#endif /* CONFIG_SMP */
+
+#define MODINFO_ATTR(field) \
+static void setup_modinfo_##field(struct module *mod, const char *s) \
+{ \
+ mod->field = kstrdup(s, GFP_KERNEL); \
+} \
+static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
+ struct module_kobject *mk, char *buffer) \
+{ \
+ return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
+} \
+static int modinfo_##field##_exists(struct module *mod) \
+{ \
+ return mod->field != NULL; \
+} \
+static void free_modinfo_##field(struct module *mod) \
+{ \
+ kfree(mod->field); \
+ mod->field = NULL; \
+} \
+static struct module_attribute modinfo_##field = { \
+ .attr = { .name = __stringify(field), .mode = 0444 }, \
+ .show = show_modinfo_##field, \
+ .setup = setup_modinfo_##field, \
+ .test = modinfo_##field##_exists, \
+ .free = free_modinfo_##field, \
+};
+
+MODINFO_ATTR(version);
+MODINFO_ATTR(srcversion);
+
+static char last_unloaded_module[MODULE_NAME_LEN+1];
+
+#ifdef CONFIG_MODULE_UNLOAD
+
+EXPORT_TRACEPOINT_SYMBOL(module_get);
+
+/* MODULE_REF_BASE is the base reference count by kmodule loader. */
+#define MODULE_REF_BASE 1
+
+/* Init the unload section of the module. */
+static int module_unload_init(struct module *mod)
+{
+ /*
+ * Initialize reference counter to MODULE_REF_BASE.
+ * refcnt == 0 means module is going.
+ */
+ atomic_set(&mod->refcnt, MODULE_REF_BASE);
+
+ INIT_LIST_HEAD(&mod->source_list);
+ INIT_LIST_HEAD(&mod->target_list);
+
+ /* Hold reference count during initialization. */
+ atomic_inc(&mod->refcnt);
+
+ return 0;
+}
+
+/* Does a already use b? */
+static int already_uses(struct module *a, struct module *b)
+{
+ struct module_use *use;
+
+ list_for_each_entry(use, &b->source_list, source_list) {
+ if (use->source == a) {
+ pr_debug("%s uses %s!\n", a->name, b->name);
+ return 1;
+ }
+ }
+ pr_debug("%s does not use %s!\n", a->name, b->name);
+ return 0;
+}
+
+/*
+ * Module a uses b
+ * - we add 'a' as a "source", 'b' as a "target" of module use
+ * - the module_use is added to the list of 'b' sources (so
+ * 'b' can walk the list to see who sourced them), and of 'a'
+ * targets (so 'a' can see what modules it targets).
+ */
+static int add_module_usage(struct module *a, struct module *b)
+{
+ struct module_use *use;
+
+ pr_debug("Allocating new usage for %s.\n", a->name);
+ use = kmalloc(sizeof(*use), GFP_ATOMIC);
+ if (!use)
+ return -ENOMEM;
+
+ use->source = a;
+ use->target = b;
+ list_add(&use->source_list, &b->source_list);
+ list_add(&use->target_list, &a->target_list);
+ return 0;
+}
+
+/* Module a uses b: caller needs module_mutex() */
+static int ref_module(struct module *a, struct module *b)
+{
+ int err;
+
+ if (b == NULL || already_uses(a, b))
+ return 0;
+
+ /* If module isn't available, we fail. */
+ err = strong_try_module_get(b);
+ if (err)
+ return err;
+
+ err = add_module_usage(a, b);
+ if (err) {
+ module_put(b);
+ return err;
+ }
+ return 0;
+}
+
+/* Clear the unload stuff of the module. */
+static void module_unload_free(struct module *mod)
+{
+ struct module_use *use, *tmp;
+
+ mutex_lock(&module_mutex);
+ list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
+ struct module *i = use->target;
+ pr_debug("%s unusing %s\n", mod->name, i->name);
+ module_put(i);
+ list_del(&use->source_list);
+ list_del(&use->target_list);
+ kfree(use);
+ }
+ mutex_unlock(&module_mutex);
+}
+
+#ifdef CONFIG_MODULE_FORCE_UNLOAD
+static inline int try_force_unload(unsigned int flags)
+{
+ int ret = (flags & O_TRUNC);
+ if (ret)
+ add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
+ return ret;
+}
+#else
+static inline int try_force_unload(unsigned int flags)
+{
+ return 0;
+}
+#endif /* CONFIG_MODULE_FORCE_UNLOAD */
+
+/* Try to release refcount of module, 0 means success. */
+static int try_release_module_ref(struct module *mod)
+{
+ int ret;
+
+ /* Try to decrement refcnt which we set at loading */
+ ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
+ BUG_ON(ret < 0);
+ if (ret)
+ /* Someone can put this right now, recover with checking */
+ ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
+
+ return ret;
+}
+
+static int try_stop_module(struct module *mod, int flags, int *forced)
+{
+ /* If it's not unused, quit unless we're forcing. */
+ if (try_release_module_ref(mod) != 0) {
+ *forced = try_force_unload(flags);
+ if (!(*forced))
+ return -EWOULDBLOCK;
+ }
+
+ /* Mark it as dying. */
+ mod->state = MODULE_STATE_GOING;
+
+ return 0;
+}
+
+/**
+ * module_refcount() - return the refcount or -1 if unloading
+ * @mod: the module we're checking
+ *
+ * Return:
+ * -1 if the module is in the process of unloading
+ * otherwise the number of references in the kernel to the module
+ */
+int module_refcount(struct module *mod)
+{
+ return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
+}
+EXPORT_SYMBOL(module_refcount);
+
+/* This exists whether we can unload or not */
+static void free_module(struct module *mod);
+
+SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
+ unsigned int, flags)
+{
+ struct module *mod;
+ char name[MODULE_NAME_LEN];
+ int ret, forced = 0;
+
+ if (!capable(CAP_SYS_MODULE) || modules_disabled)
+ return -EPERM;
+
+ if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
+ return -EFAULT;
+ name[MODULE_NAME_LEN-1] = '\0';
+
+ audit_log_kern_module(name);
+
+ if (mutex_lock_interruptible(&module_mutex) != 0)
+ return -EINTR;
+
+ mod = find_module(name);
+ if (!mod) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ if (!list_empty(&mod->source_list)) {
+ /* Other modules depend on us: get rid of them first. */
+ ret = -EWOULDBLOCK;
+ goto out;
+ }
+
+ /* Doing init or already dying? */
+ if (mod->state != MODULE_STATE_LIVE) {
+ /* FIXME: if (force), slam module count damn the torpedoes */
+ pr_debug("%s already dying\n", mod->name);
+ ret = -EBUSY;
+ goto out;
+ }
+
+ /* If it has an init func, it must have an exit func to unload */
+ if (mod->init && !mod->exit) {
+ forced = try_force_unload(flags);
+ if (!forced) {
+ /* This module can't be removed */
+ ret = -EBUSY;
+ goto out;
+ }
+ }
+
+ ret = try_stop_module(mod, flags, &forced);
+ if (ret != 0)
+ goto out;
+
+ mutex_unlock(&module_mutex);
+ /* Final destruction now no one is using it. */
+ if (mod->exit != NULL)
+ mod->exit();
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_GOING, mod);
+ klp_module_going(mod);
+ ftrace_release_mod(mod);
+
+ async_synchronize_full();
+
+ /* Store the name of the last unloaded module for diagnostic purposes */
+ strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
+
+ free_module(mod);
+ /* someone could wait for the module in add_unformed_module() */
+ wake_up_all(&module_wq);
+ return 0;
+out:
+ mutex_unlock(&module_mutex);
+ 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 = {
+ .name = symbol,
+ .gplok = true,
+ };
+
+ preempt_disable();
+ BUG_ON(!find_symbol(&fsa));
+ module_put(fsa.owner);
+ preempt_enable();
+}
+EXPORT_SYMBOL(__symbol_put);
+
+/* Note this assumes addr is a function, which it currently always is. */
+void symbol_put_addr(void *addr)
+{
+ struct module *modaddr;
+ unsigned long a = (unsigned long)dereference_function_descriptor(addr);
+
+ if (core_kernel_text(a))
+ return;
+
+ /*
+ * Even though we hold a reference on the module; we still need to
+ * disable preemption in order to safely traverse the data structure.
+ */
+ preempt_disable();
+ modaddr = __module_text_address(a);
+ BUG_ON(!modaddr);
+ module_put(modaddr);
+ preempt_enable();
+}
+EXPORT_SYMBOL_GPL(symbol_put_addr);
+
+static ssize_t show_refcnt(struct module_attribute *mattr,
+ struct module_kobject *mk, char *buffer)
+{
+ return sprintf(buffer, "%i\n", module_refcount(mk->mod));
+}
+
+static struct module_attribute modinfo_refcnt =
+ __ATTR(refcnt, 0444, show_refcnt, NULL);
+
+void __module_get(struct module *module)
+{
+ if (module) {
+ preempt_disable();
+ atomic_inc(&module->refcnt);
+ trace_module_get(module, _RET_IP_);
+ preempt_enable();
+ }
+}
+EXPORT_SYMBOL(__module_get);
+
+bool try_module_get(struct module *module)
+{
+ bool ret = true;
+
+ if (module) {
+ preempt_disable();
+ /* Note: here, we can fail to get a reference */
+ if (likely(module_is_live(module) &&
+ atomic_inc_not_zero(&module->refcnt) != 0))
+ trace_module_get(module, _RET_IP_);
+ else
+ ret = false;
+
+ preempt_enable();
+ }
+ return ret;
+}
+EXPORT_SYMBOL(try_module_get);
+
+void module_put(struct module *module)
+{
+ int ret;
+
+ if (module) {
+ preempt_disable();
+ ret = atomic_dec_if_positive(&module->refcnt);
+ WARN_ON(ret < 0); /* Failed to put refcount */
+ trace_module_put(module, _RET_IP_);
+ preempt_enable();
+ }
+}
+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)
+{
+}
+
+static int ref_module(struct module *a, struct module *b)
+{
+ return strong_try_module_get(b);
+}
+
+static inline int module_unload_init(struct module *mod)
+{
+ return 0;
+}
+#endif /* CONFIG_MODULE_UNLOAD */
+
+static size_t module_flags_taint(struct module *mod, char *buf)
+{
+ size_t l = 0;
+ int i;
+
+ for (i = 0; i < TAINT_FLAGS_COUNT; i++) {
+ if (taint_flags[i].module && test_bit(i, &mod->taints))
+ buf[l++] = taint_flags[i].c_true;
+ }
+
+ return l;
+}
+
+static ssize_t show_initstate(struct module_attribute *mattr,
+ struct module_kobject *mk, char *buffer)
+{
+ const char *state = "unknown";
+
+ switch (mk->mod->state) {
+ case MODULE_STATE_LIVE:
+ state = "live";
+ break;
+ case MODULE_STATE_COMING:
+ state = "coming";
+ break;
+ case MODULE_STATE_GOING:
+ state = "going";
+ break;
+ default:
+ BUG();
+ }
+ return sprintf(buffer, "%s\n", state);
+}
+
+static struct module_attribute modinfo_initstate =
+ __ATTR(initstate, 0444, show_initstate, NULL);
+
+static ssize_t store_uevent(struct module_attribute *mattr,
+ struct module_kobject *mk,
+ const char *buffer, size_t count)
+{
+ int rc;
+
+ rc = kobject_synth_uevent(&mk->kobj, buffer, count);
+ return rc ? rc : count;
+}
+
+struct module_attribute module_uevent =
+ __ATTR(uevent, 0200, NULL, store_uevent);
+
+static ssize_t show_coresize(struct module_attribute *mattr,
+ struct module_kobject *mk, char *buffer)
+{
+ return sprintf(buffer, "%u\n", mk->mod->core_layout.size);
+}
+
+static struct module_attribute modinfo_coresize =
+ __ATTR(coresize, 0444, show_coresize, NULL);
+
+static ssize_t show_initsize(struct module_attribute *mattr,
+ struct module_kobject *mk, char *buffer)
+{
+ return sprintf(buffer, "%u\n", mk->mod->init_layout.size);
+}
+
+static struct module_attribute modinfo_initsize =
+ __ATTR(initsize, 0444, show_initsize, NULL);
+
+static ssize_t show_taint(struct module_attribute *mattr,
+ struct module_kobject *mk, char *buffer)
+{
+ size_t l;
+
+ l = module_flags_taint(mk->mod, buffer);
+ buffer[l++] = '\n';
+ return l;
+}
+
+static struct module_attribute modinfo_taint =
+ __ATTR(taint, 0444, show_taint, NULL);
+
+static struct module_attribute *modinfo_attrs[] = {
+ &module_uevent,
+ &modinfo_version,
+ &modinfo_srcversion,
+ &modinfo_initstate,
+ &modinfo_coresize,
+ &modinfo_initsize,
+ &modinfo_taint,
+#ifdef CONFIG_MODULE_UNLOAD
+ &modinfo_refcnt,
+#endif
+ NULL,
+};
+
+static const char vermagic[] = VERMAGIC_STRING;
+
+static int try_to_force_load(struct module *mod, const char *reason)
+{
+#ifdef CONFIG_MODULE_FORCE_LOAD
+ if (!test_taint(TAINT_FORCED_MODULE))
+ pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
+ add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
+ return 0;
+#else
+ return -ENOEXEC;
+#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);
+
+static int verify_namespace_is_imported(const struct load_info *info,
+ const struct kernel_symbol *sym,
+ struct module *mod)
+{
+ const char *namespace;
+ char *imported_namespace;
+
+ namespace = kernel_symbol_namespace(sym);
+ if (namespace && namespace[0]) {
+ imported_namespace = get_modinfo(info, "import_ns");
+ while (imported_namespace) {
+ if (strcmp(namespace, imported_namespace) == 0)
+ return 0;
+ imported_namespace = get_next_modinfo(
+ info, "import_ns", imported_namespace);
+ }
+#ifdef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
+ pr_warn(
+#else
+ pr_err(
+#endif
+ "%s: module uses symbol (%s) from namespace %s, but does not import it.\n",
+ mod->name, kernel_symbol_name(sym), namespace);
+#ifndef CONFIG_MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
+ return -EINVAL;
+#endif
+ }
+ return 0;
+}
+
+static bool inherit_taint(struct module *mod, struct module *owner)
+{
+ if (!owner || !test_bit(TAINT_PROPRIETARY_MODULE, &owner->taints))
+ return true;
+
+ if (mod->using_gplonly_symbols) {
+ pr_err("%s: module using GPL-only symbols uses symbols from proprietary module %s.\n",
+ mod->name, owner->name);
+ return false;
+ }
+
+ if (!test_bit(TAINT_PROPRIETARY_MODULE, &mod->taints)) {
+ pr_warn("%s: module uses symbols from proprietary module %s, inheriting taint.\n",
+ mod->name, owner->name);
+ set_bit(TAINT_PROPRIETARY_MODULE, &mod->taints);
+ }
+ return true;
+}
+
+/* Resolve a symbol for this module. I.e. if we find one, record usage. */
+static const struct kernel_symbol *resolve_symbol(struct module *mod,
+ const struct load_info *info,
+ const char *name,
+ char ownername[])
+{
+ struct find_symbol_arg fsa = {
+ .name = name,
+ .gplok = !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)),
+ .warn = true,
+ };
+ int err;
+
+ /*
+ * The module_mutex should not be a heavily contended lock;
+ * if we get the occasional sleep here, we'll go an extra iteration
+ * in the wait_event_interruptible(), which is harmless.
+ */
+ sched_annotate_sleep();
+ mutex_lock(&module_mutex);
+ if (!find_symbol(&fsa))
+ goto unlock;
+
+ if (fsa.license == GPL_ONLY)
+ mod->using_gplonly_symbols = true;
+
+ if (!inherit_taint(mod, fsa.owner)) {
+ fsa.sym = NULL;
+ goto getname;
+ }
+
+ if (!check_version(info, name, mod, fsa.crc)) {
+ fsa.sym = ERR_PTR(-EINVAL);
+ goto getname;
+ }
+
+ err = verify_namespace_is_imported(info, fsa.sym, mod);
+ if (err) {
+ fsa.sym = ERR_PTR(err);
+ goto getname;
+ }
+
+ err = ref_module(mod, fsa.owner);
+ if (err) {
+ fsa.sym = ERR_PTR(err);
+ goto getname;
+ }
+
+getname:
+ /* We must make copy under the lock if we failed to get ref. */
+ strncpy(ownername, module_name(fsa.owner), MODULE_NAME_LEN);
+unlock:
+ mutex_unlock(&module_mutex);
+ return fsa.sym;
+}
+
+static const struct kernel_symbol *
+resolve_symbol_wait(struct module *mod,
+ const struct load_info *info,
+ const char *name)
+{
+ const struct kernel_symbol *ksym;
+ char owner[MODULE_NAME_LEN];
+
+ if (wait_event_interruptible_timeout(module_wq,
+ !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
+ || PTR_ERR(ksym) != -EBUSY,
+ 30 * HZ) <= 0) {
+ pr_warn("%s: gave up waiting for init of module %s.\n",
+ mod->name, owner);
+ }
+ 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>
+ */
+#ifdef CONFIG_SYSFS
+
+#ifdef CONFIG_KALLSYMS
+struct module_sect_attr {
+ struct bin_attribute battr;
+ unsigned long address;
+};
+
+struct module_sect_attrs {
+ struct attribute_group grp;
+ unsigned int nsections;
+ struct module_sect_attr attrs[];
+};
+
+#define MODULE_SECT_READ_SIZE (3 /* "0x", "\n" */ + (BITS_PER_LONG / 4))
+static ssize_t module_sect_read(struct file *file, struct kobject *kobj,
+ struct bin_attribute *battr,
+ char *buf, loff_t pos, size_t count)
+{
+ struct module_sect_attr *sattr =
+ container_of(battr, struct module_sect_attr, battr);
+ char bounce[MODULE_SECT_READ_SIZE + 1];
+ size_t wrote;
+
+ if (pos != 0)
+ return -EINVAL;
+
+ /*
+ * Since we're a binary read handler, we must account for the
+ * trailing NUL byte that sprintf will write: if "buf" is
+ * too small to hold the NUL, or the NUL is exactly the last
+ * byte, the read will look like it got truncated by one byte.
+ * Since there is no way to ask sprintf nicely to not write
+ * the NUL, we have to use a bounce buffer.
+ */
+ wrote = scnprintf(bounce, sizeof(bounce), "0x%px\n",
+ kallsyms_show_value(file->f_cred)
+ ? (void *)sattr->address : NULL);
+ count = min(count, wrote);
+ memcpy(buf, bounce, count);
+
+ return count;
+}
+
+static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
+{
+ unsigned int section;
+
+ for (section = 0; section < sect_attrs->nsections; section++)
+ kfree(sect_attrs->attrs[section].battr.attr.name);
+ kfree(sect_attrs);
+}
+
+static void add_sect_attrs(struct module *mod, const struct load_info *info)
+{
+ unsigned int nloaded = 0, i, size[2];
+ struct module_sect_attrs *sect_attrs;
+ struct module_sect_attr *sattr;
+ struct bin_attribute **gattr;
+
+ /* Count loaded sections and allocate structures */
+ for (i = 0; i < info->hdr->e_shnum; i++)
+ if (!sect_empty(&info->sechdrs[i]))
+ nloaded++;
+ size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded),
+ sizeof(sect_attrs->grp.bin_attrs[0]));
+ size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.bin_attrs[0]);
+ sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
+ if (sect_attrs == NULL)
+ return;
+
+ /* Setup section attributes. */
+ sect_attrs->grp.name = "sections";
+ sect_attrs->grp.bin_attrs = (void *)sect_attrs + size[0];
+
+ sect_attrs->nsections = 0;
+ sattr = &sect_attrs->attrs[0];
+ gattr = &sect_attrs->grp.bin_attrs[0];
+ for (i = 0; i < info->hdr->e_shnum; i++) {
+ Elf_Shdr *sec = &info->sechdrs[i];
+ if (sect_empty(sec))
+ continue;
+ sysfs_bin_attr_init(&sattr->battr);
+ sattr->address = sec->sh_addr;
+ sattr->battr.attr.name =
+ kstrdup(info->secstrings + sec->sh_name, GFP_KERNEL);
+ if (sattr->battr.attr.name == NULL)
+ goto out;
+ sect_attrs->nsections++;
+ sattr->battr.read = module_sect_read;
+ sattr->battr.size = MODULE_SECT_READ_SIZE;
+ sattr->battr.attr.mode = 0400;
+ *(gattr++) = &(sattr++)->battr;
+ }
+ *gattr = NULL;
+
+ if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
+ goto out;
+
+ mod->sect_attrs = sect_attrs;
+ return;
+ out:
+ free_sect_attrs(sect_attrs);
+}
+
+static void remove_sect_attrs(struct module *mod)
+{
+ if (mod->sect_attrs) {
+ sysfs_remove_group(&mod->mkobj.kobj,
+ &mod->sect_attrs->grp);
+ /*
+ * We are positive that no one is using any sect attrs
+ * at this point. Deallocate immediately.
+ */
+ free_sect_attrs(mod->sect_attrs);
+ mod->sect_attrs = NULL;
+ }
+}
+
+/*
+ * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
+ */
+
+struct module_notes_attrs {
+ struct kobject *dir;
+ unsigned int notes;
+ struct bin_attribute attrs[];
+};
+
+static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t pos, size_t count)
+{
+ /*
+ * The caller checked the pos and count against our size.
+ */
+ memcpy(buf, bin_attr->private + pos, count);
+ return count;
+}
+
+static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
+ unsigned int i)
+{
+ if (notes_attrs->dir) {
+ while (i-- > 0)
+ sysfs_remove_bin_file(notes_attrs->dir,
+ &notes_attrs->attrs[i]);
+ kobject_put(notes_attrs->dir);
+ }
+ kfree(notes_attrs);
+}
+
+static void add_notes_attrs(struct module *mod, const struct load_info *info)
+{
+ unsigned int notes, loaded, i;
+ struct module_notes_attrs *notes_attrs;
+ struct bin_attribute *nattr;
+
+ /* failed to create section attributes, so can't create notes */
+ if (!mod->sect_attrs)
+ return;
+
+ /* Count notes sections and allocate structures. */
+ notes = 0;
+ for (i = 0; i < info->hdr->e_shnum; i++)
+ if (!sect_empty(&info->sechdrs[i]) &&
+ (info->sechdrs[i].sh_type == SHT_NOTE))
+ ++notes;
+
+ if (notes == 0)
+ return;
+
+ notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes),
+ GFP_KERNEL);
+ if (notes_attrs == NULL)
+ return;
+
+ notes_attrs->notes = notes;
+ nattr = &notes_attrs->attrs[0];
+ for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
+ if (sect_empty(&info->sechdrs[i]))
+ continue;
+ if (info->sechdrs[i].sh_type == SHT_NOTE) {
+ sysfs_bin_attr_init(nattr);
+ nattr->attr.name = mod->sect_attrs->attrs[loaded].battr.attr.name;
+ nattr->attr.mode = S_IRUGO;
+ nattr->size = info->sechdrs[i].sh_size;
+ nattr->private = (void *) info->sechdrs[i].sh_addr;
+ nattr->read = module_notes_read;
+ ++nattr;
+ }
+ ++loaded;
+ }
+
+ notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
+ if (!notes_attrs->dir)
+ goto out;
+
+ for (i = 0; i < notes; ++i)
+ if (sysfs_create_bin_file(notes_attrs->dir,
+ &notes_attrs->attrs[i]))
+ goto out;
+
+ mod->notes_attrs = notes_attrs;
+ return;
+
+ out:
+ free_notes_attrs(notes_attrs, i);
+}
+
+static void remove_notes_attrs(struct module *mod)
+{
+ if (mod->notes_attrs)
+ free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
+}
+
+#else
+
+static inline void add_sect_attrs(struct module *mod,
+ const struct load_info *info)
+{
+}
+
+static inline void remove_sect_attrs(struct module *mod)
+{
+}
+
+static inline void add_notes_attrs(struct module *mod,
+ const struct load_info *info)
+{
+}
+
+static inline void remove_notes_attrs(struct module *mod)
+{
+}
+#endif /* CONFIG_KALLSYMS */
+
+static void del_usage_links(struct module *mod)
+{
+#ifdef CONFIG_MODULE_UNLOAD
+ struct module_use *use;
+
+ mutex_lock(&module_mutex);
+ list_for_each_entry(use, &mod->target_list, target_list)
+ sysfs_remove_link(use->target->holders_dir, mod->name);
+ mutex_unlock(&module_mutex);
+#endif
+}
+
+static int add_usage_links(struct module *mod)
+{
+ int ret = 0;
+#ifdef CONFIG_MODULE_UNLOAD
+ struct module_use *use;
+
+ mutex_lock(&module_mutex);
+ list_for_each_entry(use, &mod->target_list, target_list) {
+ ret = sysfs_create_link(use->target->holders_dir,
+ &mod->mkobj.kobj, mod->name);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&module_mutex);
+ if (ret)
+ del_usage_links(mod);
+#endif
+ return ret;
+}
+
+static void module_remove_modinfo_attrs(struct module *mod, int end);
+
+static int module_add_modinfo_attrs(struct module *mod)
+{
+ struct module_attribute *attr;
+ struct module_attribute *temp_attr;
+ int error = 0;
+ int i;
+
+ mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
+ (ARRAY_SIZE(modinfo_attrs) + 1)),
+ GFP_KERNEL);
+ if (!mod->modinfo_attrs)
+ return -ENOMEM;
+
+ temp_attr = mod->modinfo_attrs;
+ for (i = 0; (attr = modinfo_attrs[i]); i++) {
+ if (!attr->test || attr->test(mod)) {
+ memcpy(temp_attr, attr, sizeof(*temp_attr));
+ sysfs_attr_init(&temp_attr->attr);
+ error = sysfs_create_file(&mod->mkobj.kobj,
+ &temp_attr->attr);
+ if (error)
+ goto error_out;
+ ++temp_attr;
+ }
+ }
+
+ return 0;
+
+error_out:
+ if (i > 0)
+ module_remove_modinfo_attrs(mod, --i);
+ else
+ kfree(mod->modinfo_attrs);
+ return error;
+}
+
+static void module_remove_modinfo_attrs(struct module *mod, int end)
+{
+ struct module_attribute *attr;
+ int i;
+
+ for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
+ if (end >= 0 && i > end)
+ break;
+ /* pick a field to test for end of list */
+ if (!attr->attr.name)
+ break;
+ sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
+ if (attr->free)
+ attr->free(mod);
+ }
+ kfree(mod->modinfo_attrs);
+}
+
+static void mod_kobject_put(struct module *mod)
+{
+ DECLARE_COMPLETION_ONSTACK(c);
+ mod->mkobj.kobj_completion = &c;
+ kobject_put(&mod->mkobj.kobj);
+ wait_for_completion(&c);
+}
+
+static int mod_sysfs_init(struct module *mod)
+{
+ int err;
+ struct kobject *kobj;
+
+ if (!module_sysfs_initialized) {
+ pr_err("%s: module sysfs not initialized\n", mod->name);
+ err = -EINVAL;
+ goto out;
+ }
+
+ kobj = kset_find_obj(module_kset, mod->name);
+ if (kobj) {
+ pr_err("%s: module is already loaded\n", mod->name);
+ kobject_put(kobj);
+ err = -EINVAL;
+ goto out;
+ }
+
+ mod->mkobj.mod = mod;
+
+ memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
+ mod->mkobj.kobj.kset = module_kset;
+ err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
+ "%s", mod->name);
+ if (err)
+ mod_kobject_put(mod);
+
+out:
+ return err;
+}
+
+static int mod_sysfs_setup(struct module *mod,
+ const struct load_info *info,
+ struct kernel_param *kparam,
+ unsigned int num_params)
+{
+ int err;
+
+ err = mod_sysfs_init(mod);
+ if (err)
+ goto out;
+
+ mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
+ if (!mod->holders_dir) {
+ err = -ENOMEM;
+ goto out_unreg;
+ }
+
+ err = module_param_sysfs_setup(mod, kparam, num_params);
+ if (err)
+ goto out_unreg_holders;
+
+ err = module_add_modinfo_attrs(mod);
+ if (err)
+ goto out_unreg_param;
+
+ err = add_usage_links(mod);
+ if (err)
+ goto out_unreg_modinfo_attrs;
+
+ add_sect_attrs(mod, info);
+ add_notes_attrs(mod, info);
+
+ return 0;
+
+out_unreg_modinfo_attrs:
+ module_remove_modinfo_attrs(mod, -1);
+out_unreg_param:
+ module_param_sysfs_remove(mod);
+out_unreg_holders:
+ kobject_put(mod->holders_dir);
+out_unreg:
+ mod_kobject_put(mod);
+out:
+ return err;
+}
+
+static void mod_sysfs_fini(struct module *mod)
+{
+ remove_notes_attrs(mod);
+ remove_sect_attrs(mod);
+ mod_kobject_put(mod);
+}
+
+static void init_param_lock(struct module *mod)
+{
+ mutex_init(&mod->param_lock);
+}
+#else /* !CONFIG_SYSFS */
+
+static int mod_sysfs_setup(struct module *mod,
+ const struct load_info *info,
+ struct kernel_param *kparam,
+ unsigned int num_params)
+{
+ return 0;
+}
+
+static void mod_sysfs_fini(struct module *mod)
+{
+}
+
+static void module_remove_modinfo_attrs(struct module *mod, int end)
+{
+}
+
+static void del_usage_links(struct module *mod)
+{
+}
+
+static void init_param_lock(struct module *mod)
+{
+}
+#endif /* CONFIG_SYSFS */
+
+static void mod_sysfs_teardown(struct module *mod)
+{
+ del_usage_links(mod);
+ module_remove_modinfo_attrs(mod, -1);
+ module_param_sysfs_remove(mod);
+ kobject_put(mod->mkobj.drivers_dir);
+ kobject_put(mod->holders_dir);
+ mod_sysfs_fini(mod);
+}
+
+/*
+ * LKM RO/NX protection: protect module's text/ro-data
+ * from modification and any data from execution.
+ *
+ * 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))
+{
+ 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 */
+
+#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)
+{
+ /*
+ * This memory may be RO, and freeing RO memory in an interrupt is not
+ * supported by vmalloc.
+ */
+ WARN_ON(in_interrupt());
+ vfree(module_region);
+}
+
+void __weak module_arch_cleanup(struct module *mod)
+{
+}
+
+void __weak module_arch_freeing_init(struct module *mod)
+{
+}
+
+static void cfi_cleanup(struct module *mod);
+
+/* Free a module, remove from lists, etc. */
+static void free_module(struct module *mod)
+{
+ trace_module_free(mod);
+
+ mod_sysfs_teardown(mod);
+
+ /*
+ * We leave it in list to prevent duplicate loads, but make sure
+ * that noone uses it while it's being deconstructed.
+ */
+ mutex_lock(&module_mutex);
+ mod->state = MODULE_STATE_UNFORMED;
+ mutex_unlock(&module_mutex);
+
+ /* Remove dynamic debug info */
+ ddebug_remove_module(mod->name);
+
+ /* Arch-specific cleanup. */
+ module_arch_cleanup(mod);
+
+ /* Module unload stuff */
+ module_unload_free(mod);
+
+ /* Free any allocated parameters. */
+ destroy_params(mod->kp, mod->num_kp);
+
+ if (is_livepatch_module(mod))
+ free_module_elf(mod);
+
+ /* Now we can delete it from the lists */
+ mutex_lock(&module_mutex);
+ /* Unlink carefully: kallsyms could be walking list. */
+ list_del_rcu(&mod->list);
+ mod_tree_remove(mod);
+ /* Remove this module from bug list, this uses list_del_rcu */
+ module_bug_cleanup(mod);
+ /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
+ synchronize_rcu();
+ mutex_unlock(&module_mutex);
+
+ /* Clean up CFI for the module. */
+ cfi_cleanup(mod);
+
+ /* This may be empty, but that's OK */
+ module_arch_freeing_init(mod);
+ module_memfree(mod->init_layout.base);
+ kfree(mod->args);
+ percpu_modfree(mod);
+
+ /* Free lock-classes; relies on the preceding sync_rcu(). */
+ lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
+
+ /* Finally, free the core (containing the module structure) */
+ module_memfree(mod->core_layout.base);
+}
+
+void *__symbol_get(const char *symbol)
+{
+ struct find_symbol_arg fsa = {
+ .name = symbol,
+ .gplok = true,
+ .warn = true,
+ };
+
+ preempt_disable();
+ if (!find_symbol(&fsa) || strong_try_module_get(fsa.owner)) {
+ preempt_enable();
+ return NULL;
+ }
+ preempt_enable();
+ return (void *)kernel_symbol_value(fsa.sym);
+}
+EXPORT_SYMBOL_GPL(__symbol_get);
+
+/*
+ * Ensure that an exported symbol [global namespace] does not already exist
+ * in the kernel or in some other module's exported symbol table.
+ *
+ * You must hold the module_mutex.
+ */
+static int verify_exported_symbols(struct module *mod)
+{
+ unsigned int i;
+ const struct kernel_symbol *s;
+ struct {
+ const struct kernel_symbol *sym;
+ unsigned int num;
+ } arr[] = {
+ { mod->syms, mod->num_syms },
+ { mod->gpl_syms, mod->num_gpl_syms },
+ };
+
+ for (i = 0; i < ARRAY_SIZE(arr); i++) {
+ for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
+ struct find_symbol_arg fsa = {
+ .name = kernel_symbol_name(s),
+ .gplok = true,
+ };
+ if (find_symbol(&fsa)) {
+ pr_err("%s: exports duplicate symbol %s"
+ " (owned by %s)\n",
+ mod->name, kernel_symbol_name(s),
+ module_name(fsa.owner));
+ return -ENOEXEC;
+ }
+ }
+ }
+ return 0;
+}
+
+static bool ignore_undef_symbol(Elf_Half emachine, const char *name)
+{
+ /*
+ * On x86, PIC code and Clang non-PIC code may have call foo@PLT. GNU as
+ * before 2.37 produces an unreferenced _GLOBAL_OFFSET_TABLE_ on x86-64.
+ * i386 has a similar problem but may not deserve a fix.
+ *
+ * If we ever have to ignore many symbols, consider refactoring the code to
+ * only warn if referenced by a relocation.
+ */
+ if (emachine == EM_386 || emachine == EM_X86_64)
+ return !strcmp(name, "_GLOBAL_OFFSET_TABLE_");
+ return false;
+}
+
+/* Change all symbols so that st_value encodes the pointer directly. */
+static int simplify_symbols(struct module *mod, const struct load_info *info)
+{
+ Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
+ Elf_Sym *sym = (void *)symsec->sh_addr;
+ unsigned long secbase;
+ unsigned int i;
+ int ret = 0;
+ const struct kernel_symbol *ksym;
+
+ for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
+ const char *name = info->strtab + sym[i].st_name;
+
+ switch (sym[i].st_shndx) {
+ case SHN_COMMON:
+ /* Ignore common symbols */
+ if (!strncmp(name, "__gnu_lto", 9))
+ break;
+
+ /*
+ * We compiled with -fno-common. These are not
+ * supposed to happen.
+ */
+ pr_debug("Common symbol: %s\n", name);
+ pr_warn("%s: please compile with -fno-common\n",
+ mod->name);
+ ret = -ENOEXEC;
+ break;
+
+ case SHN_ABS:
+ /* Don't need to do anything */
+ pr_debug("Absolute symbol: 0x%08lx\n",
+ (long)sym[i].st_value);
+ break;
+
+ case SHN_LIVEPATCH:
+ /* Livepatch symbols are resolved by livepatch */
+ break;
+
+ case SHN_UNDEF:
+ ksym = resolve_symbol_wait(mod, info, name);
+ /* Ok if resolved. */
+ if (ksym && !IS_ERR(ksym)) {
+ sym[i].st_value = kernel_symbol_value(ksym);
+ break;
+ }
+
+ /* Ok if weak or ignored. */
+ if (!ksym &&
+ (ELF_ST_BIND(sym[i].st_info) == STB_WEAK ||
+ ignore_undef_symbol(info->hdr->e_machine, name)))
+ break;
+
+ ret = PTR_ERR(ksym) ?: -ENOENT;
+ pr_warn("%s: Unknown symbol %s (err %d)\n",
+ mod->name, name, ret);
+ break;
+
+ default:
+ /* Divert to percpu allocation if a percpu var. */
+ if (sym[i].st_shndx == info->index.pcpu)
+ secbase = (unsigned long)mod_percpu(mod);
+ else
+ secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
+ sym[i].st_value += secbase;
+ break;
+ }
+ }
+
+ return ret;
+}
+
+static int apply_relocations(struct module *mod, const struct load_info *info)
+{
+ unsigned int i;
+ int err = 0;
+
+ /* Now do relocations. */
+ for (i = 1; i < info->hdr->e_shnum; i++) {
+ unsigned int infosec = info->sechdrs[i].sh_info;
+
+ /* Not a valid relocation section? */
+ if (infosec >= info->hdr->e_shnum)
+ continue;
+
+ /* Don't bother with non-allocated sections */
+ if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
+ continue;
+
+ if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH)
+ err = klp_apply_section_relocs(mod, info->sechdrs,
+ info->secstrings,
+ info->strtab,
+ info->index.sym, i,
+ NULL);
+ else if (info->sechdrs[i].sh_type == SHT_REL)
+ err = apply_relocate(info->sechdrs, info->strtab,
+ info->index.sym, i, mod);
+ else if (info->sechdrs[i].sh_type == SHT_RELA)
+ err = apply_relocate_add(info->sechdrs, info->strtab,
+ info->index.sym, i, mod);
+ if (err < 0)
+ break;
+ }
+ return err;
+}
+
+/* Additional bytes needed by arch in front of individual sections */
+unsigned int __weak arch_mod_section_prepend(struct module *mod,
+ unsigned int section)
+{
+ /* default implementation just returns zero */
+ return 0;
+}
+
+/* Update size with this section: return offset. */
+static long get_offset(struct module *mod, unsigned int *size,
+ Elf_Shdr *sechdr, unsigned int section)
+{
+ long ret;
+
+ *size += arch_mod_section_prepend(mod, section);
+ ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
+ *size = ret + sechdr->sh_size;
+ return ret;
+}
+
+static bool module_init_layout_section(const char *sname)
+{
+#ifndef CONFIG_MODULE_UNLOAD
+ if (module_exit_section(sname))
+ return true;
+#endif
+ return module_init_section(sname);
+}
+
+/*
+ * Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
+ * might -- code, read-only data, read-write data, small data. Tally
+ * sizes, and place the offsets into sh_entsize fields: high bit means it
+ * belongs in init.
+ */
+static void layout_sections(struct module *mod, struct load_info *info)
+{
+ static unsigned long const masks[][2] = {
+ /*
+ * NOTE: all executable code must be the first section
+ * in this array; otherwise modify the text_size
+ * finder in the two loops below
+ */
+ { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
+ { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
+ { SHF_RO_AFTER_INIT | SHF_ALLOC, ARCH_SHF_SMALL },
+ { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
+ { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
+ };
+ unsigned int m, i;
+
+ for (i = 0; i < info->hdr->e_shnum; i++)
+ info->sechdrs[i].sh_entsize = ~0UL;
+
+ pr_debug("Core section allocation order:\n");
+ for (m = 0; m < ARRAY_SIZE(masks); ++m) {
+ for (i = 0; i < info->hdr->e_shnum; ++i) {
+ Elf_Shdr *s = &info->sechdrs[i];
+ const char *sname = info->secstrings + s->sh_name;
+
+ if ((s->sh_flags & masks[m][0]) != masks[m][0]
+ || (s->sh_flags & masks[m][1])
+ || s->sh_entsize != ~0UL
+ || module_init_layout_section(sname))
+ continue;
+ s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i);
+ pr_debug("\t%s\n", sname);
+ }
+ switch (m) {
+ case 0: /* executable */
+ mod->core_layout.size = debug_align(mod->core_layout.size);
+ mod->core_layout.text_size = mod->core_layout.size;
+ break;
+ case 1: /* RO: text and ro-data */
+ mod->core_layout.size = debug_align(mod->core_layout.size);
+ mod->core_layout.ro_size = mod->core_layout.size;
+ break;
+ case 2: /* RO after init */
+ mod->core_layout.size = debug_align(mod->core_layout.size);
+ mod->core_layout.ro_after_init_size = mod->core_layout.size;
+ break;
+ case 4: /* whole core */
+ mod->core_layout.size = debug_align(mod->core_layout.size);
+ break;
+ }
+ }
+
+ pr_debug("Init section allocation order:\n");
+ for (m = 0; m < ARRAY_SIZE(masks); ++m) {
+ for (i = 0; i < info->hdr->e_shnum; ++i) {
+ Elf_Shdr *s = &info->sechdrs[i];
+ const char *sname = info->secstrings + s->sh_name;
+
+ if ((s->sh_flags & masks[m][0]) != masks[m][0]
+ || (s->sh_flags & masks[m][1])
+ || s->sh_entsize != ~0UL
+ || !module_init_layout_section(sname))
+ continue;
+ s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i)
+ | INIT_OFFSET_MASK);
+ pr_debug("\t%s\n", sname);
+ }
+ switch (m) {
+ case 0: /* executable */
+ mod->init_layout.size = debug_align(mod->init_layout.size);
+ mod->init_layout.text_size = mod->init_layout.size;
+ break;
+ case 1: /* RO: text and ro-data */
+ mod->init_layout.size = debug_align(mod->init_layout.size);
+ mod->init_layout.ro_size = mod->init_layout.size;
+ break;
+ case 2:
+ /*
+ * RO after init doesn't apply to init_layout (only
+ * core_layout), so it just takes the value of ro_size.
+ */
+ mod->init_layout.ro_after_init_size = mod->init_layout.ro_size;
+ break;
+ case 4: /* whole init */
+ mod->init_layout.size = debug_align(mod->init_layout.size);
+ break;
+ }
+ }
+}
+
+static void set_license(struct module *mod, const char *license)
+{
+ if (!license)
+ license = "unspecified";
+
+ if (!license_is_gpl_compatible(license)) {
+ if (!test_taint(TAINT_PROPRIETARY_MODULE))
+ pr_warn("%s: module license '%s' taints kernel.\n",
+ mod->name, license);
+ add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
+ LOCKDEP_NOW_UNRELIABLE);
+ }
+}
+
+/* Parse tag=value strings from .modinfo section */
+static char *next_string(char *string, unsigned long *secsize)
+{
+ /* Skip non-zero chars */
+ while (string[0]) {
+ string++;
+ if ((*secsize)-- <= 1)
+ return NULL;
+ }
+
+ /* Skip any zero padding. */
+ while (!string[0]) {
+ string++;
+ if ((*secsize)-- <= 1)
+ return NULL;
+ }
+ return string;
+}
+
+static char *get_next_modinfo(const struct load_info *info, const char *tag,
+ char *prev)
+{
+ char *p;
+ unsigned int taglen = strlen(tag);
+ Elf_Shdr *infosec = &info->sechdrs[info->index.info];
+ unsigned long size = infosec->sh_size;
+
+ /*
+ * get_modinfo() calls made before rewrite_section_headers()
+ * must use sh_offset, as sh_addr isn't set!
+ */
+ char *modinfo = (char *)info->hdr + infosec->sh_offset;
+
+ if (prev) {
+ size -= prev - modinfo;
+ modinfo = next_string(prev, &size);
+ }
+
+ for (p = modinfo; p; p = next_string(p, &size)) {
+ if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
+ return p + taglen + 1;
+ }
+ return NULL;
+}
+
+static char *get_modinfo(const struct load_info *info, const char *tag)
+{
+ return get_next_modinfo(info, tag, NULL);
+}
+
+static void setup_modinfo(struct module *mod, struct load_info *info)
+{
+ struct module_attribute *attr;
+ int i;
+
+ for (i = 0; (attr = modinfo_attrs[i]); i++) {
+ if (attr->setup)
+ attr->setup(mod, get_modinfo(info, attr->attr.name));
+ }
+}
+
+static void free_modinfo(struct module *mod)
+{
+ struct module_attribute *attr;
+ int i;
+
+ for (i = 0; (attr = modinfo_attrs[i]); i++) {
+ if (attr->free)
+ attr->free(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)
+ return;
+ ddebug_add_module(debug, num, mod->name);
+}
+
+static void dynamic_debug_remove(struct module *mod, struct _ddebug *debug)
+{
+ if (debug)
+ ddebug_remove_module(mod->name);
+}
+
+void * __weak module_alloc(unsigned long size)
+{
+ return __vmalloc_node_range(size, 1, VMALLOC_START, VMALLOC_END,
+ GFP_KERNEL, PAGE_KERNEL_EXEC, VM_FLUSH_RESET_PERMS,
+ NUMA_NO_NODE, __builtin_return_address(0));
+}
+
+bool __weak module_init_section(const char *name)
+{
+ return strstarts(name, ".init");
+}
+
+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
+
+#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)
+ unsigned long long secend;
+#else
+ unsigned long secend;
+#endif
+
+ /*
+ * Check for both overflow and offset/size being
+ * too large.
+ */
+ secend = shdr->sh_offset + shdr->sh_size;
+ if (secend < shdr->sh_offset || secend > info->len)
+ return -ENOEXEC;
+
+ return 0;
+}
+
+/*
+ * Sanity checks against invalid binaries, wrong arch, weird elf version.
+ *
+ * Also do basic validity checks against section offsets and sizes, the
+ * section name string table, and the indices used for it (sh_name).
+ */
+static int elf_validity_check(struct load_info *info)
+{
+ unsigned int i;
+ Elf_Shdr *shdr, *strhdr;
+ int err;
+
+ if (info->len < sizeof(*(info->hdr))) {
+ pr_err("Invalid ELF header len %lu\n", info->len);
+ goto no_exec;
+ }
+
+ if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0) {
+ pr_err("Invalid ELF header magic: != %s\n", ELFMAG);
+ goto no_exec;
+ }
+ if (info->hdr->e_type != ET_REL) {
+ pr_err("Invalid ELF header type: %u != %u\n",
+ info->hdr->e_type, ET_REL);
+ goto no_exec;
+ }
+ if (!elf_check_arch(info->hdr)) {
+ pr_err("Invalid architecture in ELF header: %u\n",
+ info->hdr->e_machine);
+ goto no_exec;
+ }
+ if (info->hdr->e_shentsize != sizeof(Elf_Shdr)) {
+ pr_err("Invalid ELF section header size\n");
+ goto no_exec;
+ }
+
+ /*
+ * e_shnum is 16 bits, and sizeof(Elf_Shdr) is
+ * known and small. So e_shnum * sizeof(Elf_Shdr)
+ * will not overflow unsigned long on any platform.
+ */
+ if (info->hdr->e_shoff >= info->len
+ || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
+ info->len - info->hdr->e_shoff)) {
+ pr_err("Invalid ELF section header overflow\n");
+ goto no_exec;
+ }
+
+ info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
+
+ /*
+ * Verify if the section name table index is valid.
+ */
+ if (info->hdr->e_shstrndx == SHN_UNDEF
+ || info->hdr->e_shstrndx >= info->hdr->e_shnum) {
+ pr_err("Invalid ELF section name index: %d || e_shstrndx (%d) >= e_shnum (%d)\n",
+ info->hdr->e_shstrndx, info->hdr->e_shstrndx,
+ info->hdr->e_shnum);
+ goto no_exec;
+ }
+
+ strhdr = &info->sechdrs[info->hdr->e_shstrndx];
+ err = validate_section_offset(info, strhdr);
+ if (err < 0) {
+ pr_err("Invalid ELF section hdr(type %u)\n", strhdr->sh_type);
+ return err;
+ }
+
+ /*
+ * The section name table must be NUL-terminated, as required
+ * by the spec. This makes strcmp and pr_* calls that access
+ * strings in the section safe.
+ */
+ info->secstrings = (void *)info->hdr + strhdr->sh_offset;
+ if (info->secstrings[strhdr->sh_size - 1] != '\0') {
+ pr_err("ELF Spec violation: section name table isn't null terminated\n");
+ goto no_exec;
+ }
+
+ /*
+ * The code assumes that section 0 has a length of zero and
+ * an addr of zero, so check for it.
+ */
+ if (info->sechdrs[0].sh_type != SHT_NULL
+ || info->sechdrs[0].sh_size != 0
+ || info->sechdrs[0].sh_addr != 0) {
+ pr_err("ELF Spec violation: section 0 type(%d)!=SH_NULL or non-zero len or addr\n",
+ info->sechdrs[0].sh_type);
+ goto no_exec;
+ }
+
+ for (i = 1; i < info->hdr->e_shnum; i++) {
+ shdr = &info->sechdrs[i];
+ switch (shdr->sh_type) {
+ case SHT_NULL:
+ case SHT_NOBITS:
+ continue;
+ case SHT_SYMTAB:
+ if (shdr->sh_link == SHN_UNDEF
+ || shdr->sh_link >= info->hdr->e_shnum) {
+ pr_err("Invalid ELF sh_link!=SHN_UNDEF(%d) or (sh_link(%d) >= hdr->e_shnum(%d)\n",
+ shdr->sh_link, shdr->sh_link,
+ info->hdr->e_shnum);
+ goto no_exec;
+ }
+ fallthrough;
+ default:
+ err = validate_section_offset(info, shdr);
+ if (err < 0) {
+ pr_err("Invalid ELF section in module (section %u type %u)\n",
+ i, shdr->sh_type);
+ return err;
+ }
+
+ if (shdr->sh_flags & SHF_ALLOC) {
+ if (shdr->sh_name >= strhdr->sh_size) {
+ pr_err("Invalid ELF section name in module (section %u type %u)\n",
+ i, shdr->sh_type);
+ return -ENOEXEC;
+ }
+ }
+ break;
+ }
+ }
+
+ return 0;
+
+no_exec:
+ return -ENOEXEC;
+}
+
+#define COPY_CHUNK_SIZE (16*PAGE_SIZE)
+
+static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len)
+{
+ do {
+ unsigned long n = min(len, COPY_CHUNK_SIZE);
+
+ if (copy_from_user(dst, usrc, n) != 0)
+ return -EFAULT;
+ cond_resched();
+ dst += n;
+ usrc += n;
+ len -= n;
+ } while (len);
+ 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;
+ 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;
+ }
+
+ return 0;
+}
+#endif /* CONFIG_LIVEPATCH */
+
+static void check_modinfo_retpoline(struct module *mod, struct load_info *info)
+{
+ if (retpoline_module_ok(get_modinfo(info, "retpoline")))
+ return;
+
+ pr_warn("%s: loading module not compiled with retpoline compiler.\n",
+ mod->name);
+}
+
+/* Sets info->hdr and info->len. */
+static int copy_module_from_user(const void __user *umod, unsigned long len,
+ struct load_info *info)
+{
+ int err;
+
+ info->len = len;
+ if (info->len < sizeof(*(info->hdr)))
+ return -ENOEXEC;
+
+ err = security_kernel_load_data(LOADING_MODULE, true);
+ if (err)
+ return err;
+
+ /* Suck in entire file: we'll want most of it. */
+ info->hdr = __vmalloc(info->len, GFP_KERNEL | __GFP_NOWARN);
+ if (!info->hdr)
+ return -ENOMEM;
+
+ if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
+ err = -EFAULT;
+ goto out;
+ }
+
+ err = security_kernel_post_load_data((char *)info->hdr, info->len,
+ LOADING_MODULE, "init_module");
+out:
+ if (err)
+ vfree(info->hdr);
+
+ return err;
+}
+
+static void free_copy(struct load_info *info, int flags)
+{
+ if (flags & MODULE_INIT_COMPRESSED_FILE)
+ module_decompress_cleanup(info);
+ else
+ vfree(info->hdr);
+}
+
+static int rewrite_section_headers(struct load_info *info, int flags)
+{
+ unsigned int i;
+
+ /* This should always be true, but let's be sure. */
+ info->sechdrs[0].sh_addr = 0;
+
+ for (i = 1; i < info->hdr->e_shnum; i++) {
+ Elf_Shdr *shdr = &info->sechdrs[i];
+
+ /*
+ * Mark all sections sh_addr with their address in the
+ * temporary image.
+ */
+ shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
+
+ }
+
+ /* Track but don't keep modinfo and version sections. */
+ info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
+ info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
+
+ return 0;
+}
+
+/*
+ * Set up our basic convenience variables (pointers to section headers,
+ * search for module section index etc), and do some basic section
+ * verification.
+ *
+ * Set info->mod to the temporary copy of the module in info->hdr. The final one
+ * will be allocated in move_module().
+ */
+static int setup_load_info(struct load_info *info, int flags)
+{
+ unsigned int i;
+
+ /* Try to find a name early so we can log errors with a module name */
+ info->index.info = find_sec(info, ".modinfo");
+ if (info->index.info)
+ info->name = get_modinfo(info, "name");
+
+ /* Find internal symbols and strings. */
+ for (i = 1; i < info->hdr->e_shnum; i++) {
+ if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
+ info->index.sym = i;
+ info->index.str = info->sechdrs[i].sh_link;
+ info->strtab = (char *)info->hdr
+ + info->sechdrs[info->index.str].sh_offset;
+ break;
+ }
+ }
+
+ if (info->index.sym == 0) {
+ pr_warn("%s: module has no symbols (stripped?)\n",
+ info->name ?: "(missing .modinfo section or name field)");
+ return -ENOEXEC;
+ }
+
+ info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
+ if (!info->index.mod) {
+ pr_warn("%s: No module found in object\n",
+ info->name ?: "(missing .modinfo section or name field)");
+ return -ENOEXEC;
+ }
+ /* This is temporary: point mod into copy of data. */
+ info->mod = (void *)info->hdr + info->sechdrs[info->index.mod].sh_offset;
+
+ /*
+ * If we didn't load the .modinfo 'name' field earlier, fall back to
+ * on-disk struct mod 'name' field.
+ */
+ if (!info->name)
+ info->name = info->mod->name;
+
+ if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
+ info->index.vers = 0; /* Pretend no __versions section! */
+ else
+ info->index.vers = find_sec(info, "__versions");
+
+ info->index.pcpu = find_pcpusec(info);
+
+ return 0;
+}
+
+static int check_modinfo(struct module *mod, struct load_info *info, int flags)
+{
+ const char *modmagic = get_modinfo(info, "vermagic");
+ int err;
+
+ if (flags & MODULE_INIT_IGNORE_VERMAGIC)
+ modmagic = NULL;
+
+ /* This is allowed: modprobe --force will invalidate it. */
+ if (!modmagic) {
+ err = try_to_force_load(mod, "bad vermagic");
+ if (err)
+ return err;
+ } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
+ pr_err("%s: version magic '%s' should be '%s'\n",
+ info->name, modmagic, vermagic);
+ return -ENOEXEC;
+ }
+
+ if (!get_modinfo(info, "intree")) {
+ if (!test_taint(TAINT_OOT_MODULE))
+ pr_warn("%s: loading out-of-tree module taints kernel.\n",
+ mod->name);
+ add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
+ }
+
+ check_modinfo_retpoline(mod, info);
+
+ if (get_modinfo(info, "staging")) {
+ add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
+ pr_warn("%s: module is from the staging directory, the quality "
+ "is unknown, you have been warned.\n", mod->name);
+ }
+
+ err = check_modinfo_livepatch(mod, info);
+ if (err)
+ return err;
+
+ /* Set up license info based on the info section */
+ set_license(mod, get_modinfo(info, "license"));
+
+ return 0;
+}
+
+static int find_module_sections(struct module *mod, struct load_info *info)
+{
+ mod->kp = section_objs(info, "__param",
+ sizeof(*mod->kp), &mod->num_kp);
+ mod->syms = section_objs(info, "__ksymtab",
+ sizeof(*mod->syms), &mod->num_syms);
+ mod->crcs = section_addr(info, "__kcrctab");
+ mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
+ sizeof(*mod->gpl_syms),
+ &mod->num_gpl_syms);
+ mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
+
+#ifdef CONFIG_CONSTRUCTORS
+ mod->ctors = section_objs(info, ".ctors",
+ sizeof(*mod->ctors), &mod->num_ctors);
+ if (!mod->ctors)
+ mod->ctors = section_objs(info, ".init_array",
+ sizeof(*mod->ctors), &mod->num_ctors);
+ else if (find_sec(info, ".init_array")) {
+ /*
+ * This shouldn't happen with same compiler and binutils
+ * building all parts of the module.
+ */
+ pr_warn("%s: has both .ctors and .init_array.\n",
+ mod->name);
+ return -EINVAL;
+ }
+#endif
+
+ mod->noinstr_text_start = section_objs(info, ".noinstr.text", 1,
+ &mod->noinstr_text_size);
+
+#ifdef CONFIG_TRACEPOINTS
+ mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
+ sizeof(*mod->tracepoints_ptrs),
+ &mod->num_tracepoints);
+#endif
+#ifdef CONFIG_TREE_SRCU
+ mod->srcu_struct_ptrs = section_objs(info, "___srcu_struct_ptrs",
+ sizeof(*mod->srcu_struct_ptrs),
+ &mod->num_srcu_structs);
+#endif
+#ifdef CONFIG_BPF_EVENTS
+ mod->bpf_raw_events = section_objs(info, "__bpf_raw_tp_map",
+ sizeof(*mod->bpf_raw_events),
+ &mod->num_bpf_raw_events);
+#endif
+#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
+ mod->btf_data = any_section_objs(info, ".BTF", 1, &mod->btf_data_size);
+#endif
+#ifdef CONFIG_JUMP_LABEL
+ mod->jump_entries = section_objs(info, "__jump_table",
+ sizeof(*mod->jump_entries),
+ &mod->num_jump_entries);
+#endif
+#ifdef CONFIG_EVENT_TRACING
+ mod->trace_events = section_objs(info, "_ftrace_events",
+ sizeof(*mod->trace_events),
+ &mod->num_trace_events);
+ mod->trace_evals = section_objs(info, "_ftrace_eval_map",
+ sizeof(*mod->trace_evals),
+ &mod->num_trace_evals);
+#endif
+#ifdef CONFIG_TRACING
+ mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
+ sizeof(*mod->trace_bprintk_fmt_start),
+ &mod->num_trace_bprintk_fmt);
+#endif
+#ifdef CONFIG_FTRACE_MCOUNT_RECORD
+ /* sechdrs[0].sh_size is always zero */
+ mod->ftrace_callsites = section_objs(info, FTRACE_CALLSITE_SECTION,
+ sizeof(*mod->ftrace_callsites),
+ &mod->num_ftrace_callsites);
+#endif
+#ifdef CONFIG_FUNCTION_ERROR_INJECTION
+ mod->ei_funcs = section_objs(info, "_error_injection_whitelist",
+ sizeof(*mod->ei_funcs),
+ &mod->num_ei_funcs);
+#endif
+#ifdef CONFIG_KPROBES
+ mod->kprobes_text_start = section_objs(info, ".kprobes.text", 1,
+ &mod->kprobes_text_size);
+ mod->kprobe_blacklist = section_objs(info, "_kprobe_blacklist",
+ sizeof(unsigned long),
+ &mod->num_kprobe_blacklist);
+#endif
+#ifdef CONFIG_PRINTK_INDEX
+ mod->printk_index_start = section_objs(info, ".printk_index",
+ sizeof(*mod->printk_index_start),
+ &mod->printk_index_size);
+#endif
+#ifdef CONFIG_HAVE_STATIC_CALL_INLINE
+ mod->static_call_sites = section_objs(info, ".static_call_sites",
+ sizeof(*mod->static_call_sites),
+ &mod->num_static_call_sites);
+#endif
+ mod->extable = section_objs(info, "__ex_table",
+ sizeof(*mod->extable), &mod->num_exentries);
+
+ if (section_addr(info, "__obsparm"))
+ pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
+
+ info->debug = section_objs(info, "__dyndbg",
+ sizeof(*info->debug), &info->num_debug);
+
+ return 0;
+}
+
+static int move_module(struct module *mod, struct load_info *info)
+{
+ int i;
+ void *ptr;
+
+ /* Do the allocs. */
+ ptr = module_alloc(mod->core_layout.size);
+ /*
+ * The pointer to this block is stored in the module structure
+ * which is inside the block. Just mark it as not being a
+ * leak.
+ */
+ kmemleak_not_leak(ptr);
+ if (!ptr)
+ return -ENOMEM;
+
+ memset(ptr, 0, mod->core_layout.size);
+ mod->core_layout.base = ptr;
+
+ if (mod->init_layout.size) {
+ ptr = module_alloc(mod->init_layout.size);
+ /*
+ * The pointer to this block is stored in the module structure
+ * which is inside the block. This block doesn't need to be
+ * scanned as it contains data and code that will be freed
+ * after the module is initialized.
+ */
+ kmemleak_ignore(ptr);
+ if (!ptr) {
+ module_memfree(mod->core_layout.base);
+ return -ENOMEM;
+ }
+ memset(ptr, 0, mod->init_layout.size);
+ mod->init_layout.base = ptr;
+ } else
+ mod->init_layout.base = NULL;
+
+ /* Transfer each section which specifies SHF_ALLOC */
+ pr_debug("final section addresses:\n");
+ for (i = 0; i < info->hdr->e_shnum; i++) {
+ void *dest;
+ Elf_Shdr *shdr = &info->sechdrs[i];
+
+ if (!(shdr->sh_flags & SHF_ALLOC))
+ continue;
+
+ if (shdr->sh_entsize & INIT_OFFSET_MASK)
+ dest = mod->init_layout.base
+ + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
+ else
+ dest = mod->core_layout.base + shdr->sh_entsize;
+
+ if (shdr->sh_type != SHT_NOBITS)
+ memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
+ /* Update sh_addr to point to copy in image. */
+ shdr->sh_addr = (unsigned long)dest;
+ pr_debug("\t0x%lx %s\n",
+ (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
+ }
+
+ return 0;
+}
+
+static int check_module_license_and_versions(struct module *mod)
+{
+ int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE);
+
+ /*
+ * ndiswrapper is under GPL by itself, but loads proprietary modules.
+ * Don't use add_taint_module(), as it would prevent ndiswrapper from
+ * using GPL-only symbols it needs.
+ */
+ if (strcmp(mod->name, "ndiswrapper") == 0)
+ add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
+
+ /* driverloader was caught wrongly pretending to be under GPL */
+ if (strcmp(mod->name, "driverloader") == 0)
+ add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
+ LOCKDEP_NOW_UNRELIABLE);
+
+ /* lve claims to be GPL but upstream won't provide source */
+ if (strcmp(mod->name, "lve") == 0)
+ add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
+ LOCKDEP_NOW_UNRELIABLE);
+
+ if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE))
+ pr_warn("%s: module license taints kernel.\n", mod->name);
+
+#ifdef CONFIG_MODVERSIONS
+ if ((mod->num_syms && !mod->crcs) ||
+ (mod->num_gpl_syms && !mod->gpl_crcs)) {
+ return try_to_force_load(mod,
+ "no versions for exported symbols");
+ }
+#endif
+ return 0;
+}
+
+static void flush_module_icache(const struct module *mod)
+{
+ /*
+ * Flush the instruction cache, since we've played with text.
+ * Do it before processing of module parameters, so the module
+ * can provide parameter accessor functions of its own.
+ */
+ if (mod->init_layout.base)
+ flush_icache_range((unsigned long)mod->init_layout.base,
+ (unsigned long)mod->init_layout.base
+ + mod->init_layout.size);
+ flush_icache_range((unsigned long)mod->core_layout.base,
+ (unsigned long)mod->core_layout.base + mod->core_layout.size);
+}
+
+int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
+ Elf_Shdr *sechdrs,
+ char *secstrings,
+ struct module *mod)
+{
+ return 0;
+}
+
+/* module_blacklist is a comma-separated list of module names */
+static char *module_blacklist;
+static bool blacklisted(const char *module_name)
+{
+ const char *p;
+ size_t len;
+
+ if (!module_blacklist)
+ return false;
+
+ for (p = module_blacklist; *p; p += len) {
+ len = strcspn(p, ",");
+ if (strlen(module_name) == len && !memcmp(module_name, p, len))
+ return true;
+ if (p[len] == ',')
+ len++;
+ }
+ return false;
+}
+core_param(module_blacklist, module_blacklist, charp, 0400);
+
+static struct module *layout_and_allocate(struct load_info *info, int flags)
+{
+ struct module *mod;
+ unsigned int ndx;
+ int err;
+
+ err = check_modinfo(info->mod, info, flags);
+ if (err)
+ return ERR_PTR(err);
+
+ /* Allow arches to frob section contents and sizes. */
+ err = module_frob_arch_sections(info->hdr, info->sechdrs,
+ info->secstrings, info->mod);
+ if (err < 0)
+ return ERR_PTR(err);
+
+ err = module_enforce_rwx_sections(info->hdr, info->sechdrs,
+ info->secstrings, info->mod);
+ if (err < 0)
+ return ERR_PTR(err);
+
+ /* We will do a special allocation for per-cpu sections later. */
+ info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
+
+ /*
+ * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
+ * layout_sections() can put it in the right place.
+ * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
+ */
+ ndx = find_sec(info, ".data..ro_after_init");
+ if (ndx)
+ info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT;
+ /*
+ * Mark the __jump_table section as ro_after_init as well: these data
+ * structures are never modified, with the exception of entries that
+ * refer to code in the __init section, which are annotated as such
+ * at module load time.
+ */
+ ndx = find_sec(info, "__jump_table");
+ if (ndx)
+ info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT;
+
+ /*
+ * Determine total sizes, and put offsets in sh_entsize. For now
+ * this is done generically; there doesn't appear to be any
+ * special cases for the architectures.
+ */
+ layout_sections(info->mod, info);
+ layout_symtab(info->mod, info);
+
+ /* Allocate and move to the final place */
+ err = move_module(info->mod, info);
+ if (err)
+ return ERR_PTR(err);
+
+ /* Module has been copied to its final place now: return it. */
+ mod = (void *)info->sechdrs[info->index.mod].sh_addr;
+ kmemleak_load_module(mod, info);
+ return mod;
+}
+
+/* mod is no longer valid after this! */
+static void module_deallocate(struct module *mod, struct load_info *info)
+{
+ percpu_modfree(mod);
+ module_arch_freeing_init(mod);
+ module_memfree(mod->init_layout.base);
+ module_memfree(mod->core_layout.base);
+}
+
+int __weak module_finalize(const Elf_Ehdr *hdr,
+ const Elf_Shdr *sechdrs,
+ struct module *me)
+{
+ return 0;
+}
+
+static int post_relocation(struct module *mod, const struct load_info *info)
+{
+ /* Sort exception table now relocations are done. */
+ sort_extable(mod->extable, mod->extable + mod->num_exentries);
+
+ /* Copy relocated percpu area over. */
+ percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
+ info->sechdrs[info->index.pcpu].sh_size);
+
+ /* Setup kallsyms-specific fields. */
+ add_kallsyms(mod, info);
+
+ /* Arch-specific module finalizing. */
+ return module_finalize(info->hdr, info->sechdrs, mod);
+}
+
+/* Is this module of this name done loading? No locks held. */
+static bool finished_loading(const char *name)
+{
+ struct module *mod;
+ bool ret;
+
+ /*
+ * The module_mutex should not be a heavily contended lock;
+ * if we get the occasional sleep here, we'll go an extra iteration
+ * in the wait_event_interruptible(), which is harmless.
+ */
+ sched_annotate_sleep();
+ mutex_lock(&module_mutex);
+ mod = find_module_all(name, strlen(name), true);
+ ret = !mod || mod->state == MODULE_STATE_LIVE;
+ mutex_unlock(&module_mutex);
+
+ return ret;
+}
+
+/* Call module constructors. */
+static void do_mod_ctors(struct module *mod)
+{
+#ifdef CONFIG_CONSTRUCTORS
+ unsigned long i;
+
+ for (i = 0; i < mod->num_ctors; i++)
+ mod->ctors[i]();
+#endif
+}
+
+/* For freeing module_init on success, in case kallsyms traversing */
+struct mod_initfree {
+ struct llist_node node;
+ void *module_init;
+};
+
+static void do_free_init(struct work_struct *w)
+{
+ struct llist_node *pos, *n, *list;
+ struct mod_initfree *initfree;
+
+ list = llist_del_all(&init_free_list);
+
+ synchronize_rcu();
+
+ llist_for_each_safe(pos, n, list) {
+ initfree = container_of(pos, struct mod_initfree, node);
+ module_memfree(initfree->module_init);
+ kfree(initfree);
+ }
+}
+
+/*
+ * This is where the real work happens.
+ *
+ * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
+ * helper command 'lx-symbols'.
+ */
+static noinline int do_init_module(struct module *mod)
+{
+ int ret = 0;
+ struct mod_initfree *freeinit;
+
+ freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
+ if (!freeinit) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+ freeinit->module_init = mod->init_layout.base;
+
+ do_mod_ctors(mod);
+ /* Start the module */
+ if (mod->init != NULL)
+ ret = do_one_initcall(mod->init);
+ if (ret < 0) {
+ goto fail_free_freeinit;
+ }
+ if (ret > 0) {
+ pr_warn("%s: '%s'->init suspiciously returned %d, it should "
+ "follow 0/-E convention\n"
+ "%s: loading module anyway...\n",
+ __func__, mod->name, ret, __func__);
+ dump_stack();
+ }
+
+ /* Now it's a first class citizen! */
+ mod->state = MODULE_STATE_LIVE;
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_LIVE, mod);
+
+ /* Delay uevent until module has finished its init routine */
+ kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
+
+ /*
+ * We need to finish all async code before the module init sequence
+ * is done. This has potential to deadlock if synchronous module
+ * loading is requested from async (which is not allowed!).
+ *
+ * See commit 0fdff3ec6d87 ("async, kmod: warn on synchronous
+ * request_module() from async workers") for more details.
+ */
+ if (!mod->async_probe_requested)
+ async_synchronize_full();
+
+ ftrace_free_mem(mod, mod->init_layout.base, mod->init_layout.base +
+ mod->init_layout.size);
+ mutex_lock(&module_mutex);
+ /* Drop initial reference. */
+ module_put(mod);
+ trim_init_extable(mod);
+#ifdef CONFIG_KALLSYMS
+ /* Switch to core kallsyms now init is done: kallsyms may be walking! */
+ rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
+#endif
+ module_enable_ro(mod, true);
+ mod_tree_remove_init(mod);
+ module_arch_freeing_init(mod);
+ mod->init_layout.base = NULL;
+ mod->init_layout.size = 0;
+ mod->init_layout.ro_size = 0;
+ mod->init_layout.ro_after_init_size = 0;
+ mod->init_layout.text_size = 0;
+#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
+ /* .BTF is not SHF_ALLOC and will get removed, so sanitize pointer */
+ mod->btf_data = NULL;
+#endif
+ /*
+ * We want to free module_init, but be aware that kallsyms may be
+ * walking this with preempt disabled. In all the failure paths, we
+ * call synchronize_rcu(), but we don't want to slow down the success
+ * path. module_memfree() cannot be called in an interrupt, so do the
+ * work and call synchronize_rcu() in a work queue.
+ *
+ * Note that module_alloc() on most architectures creates W+X page
+ * mappings which won't be cleaned up until do_free_init() runs. Any
+ * code such as mark_rodata_ro() which depends on those mappings to
+ * be cleaned up needs to sync with the queued work - ie
+ * rcu_barrier()
+ */
+ if (llist_add(&freeinit->node, &init_free_list))
+ schedule_work(&init_free_wq);
+
+ mutex_unlock(&module_mutex);
+ wake_up_all(&module_wq);
+
+ return 0;
+
+fail_free_freeinit:
+ kfree(freeinit);
+fail:
+ /* Try to protect us from buggy refcounters. */
+ mod->state = MODULE_STATE_GOING;
+ synchronize_rcu();
+ module_put(mod);
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_GOING, mod);
+ klp_module_going(mod);
+ ftrace_release_mod(mod);
+ free_module(mod);
+ wake_up_all(&module_wq);
+ return ret;
+}
+
+static int may_init_module(void)
+{
+ if (!capable(CAP_SYS_MODULE) || modules_disabled)
+ return -EPERM;
+
+ return 0;
+}
+
+/*
+ * We try to place it in the list now to make sure it's unique before
+ * we dedicate too many resources. In particular, temporary percpu
+ * memory exhaustion.
+ */
+static int add_unformed_module(struct module *mod)
+{
+ int err;
+ struct module *old;
+
+ mod->state = MODULE_STATE_UNFORMED;
+
+again:
+ mutex_lock(&module_mutex);
+ old = find_module_all(mod->name, strlen(mod->name), true);
+ if (old != NULL) {
+ if (old->state != MODULE_STATE_LIVE) {
+ /* Wait in case it fails to load. */
+ mutex_unlock(&module_mutex);
+ err = wait_event_interruptible(module_wq,
+ finished_loading(mod->name));
+ if (err)
+ goto out_unlocked;
+ goto again;
+ }
+ err = -EEXIST;
+ goto out;
+ }
+ mod_update_bounds(mod);
+ list_add_rcu(&mod->list, &modules);
+ mod_tree_insert(mod);
+ err = 0;
+
+out:
+ mutex_unlock(&module_mutex);
+out_unlocked:
+ return err;
+}
+
+static int complete_formation(struct module *mod, struct load_info *info)
+{
+ int err;
+
+ mutex_lock(&module_mutex);
+
+ /* Find duplicate symbols (must be called under lock). */
+ err = verify_exported_symbols(mod);
+ if (err < 0)
+ goto out;
+
+ /* This relies on module_mutex for list integrity. */
+ module_bug_finalize(info->hdr, info->sechdrs, mod);
+
+ module_enable_ro(mod, false);
+ module_enable_nx(mod);
+ module_enable_x(mod);
+
+ /*
+ * Mark state as coming so strong_try_module_get() ignores us,
+ * but kallsyms etc. can see us.
+ */
+ mod->state = MODULE_STATE_COMING;
+ mutex_unlock(&module_mutex);
+
+ return 0;
+
+out:
+ mutex_unlock(&module_mutex);
+ return err;
+}
+
+static int prepare_coming_module(struct module *mod)
+{
+ int err;
+
+ ftrace_module_enable(mod);
+ err = klp_module_coming(mod);
+ if (err)
+ return err;
+
+ err = blocking_notifier_call_chain_robust(&module_notify_list,
+ MODULE_STATE_COMING, MODULE_STATE_GOING, mod);
+ err = notifier_to_errno(err);
+ if (err)
+ klp_module_going(mod);
+
+ return err;
+}
+
+static int unknown_module_param_cb(char *param, char *val, const char *modname,
+ void *arg)
+{
+ struct module *mod = arg;
+ int ret;
+
+ if (strcmp(param, "async_probe") == 0) {
+ mod->async_probe_requested = true;
+ return 0;
+ }
+
+ /* Check for magic 'dyndbg' arg */
+ ret = ddebug_dyndbg_module_param_cb(param, val, modname);
+ if (ret != 0)
+ pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
+ return 0;
+}
+
+static void cfi_init(struct module *mod);
+
+/*
+ * Allocate and load the module: note that size of section 0 is always
+ * zero, and we rely on this for optional sections.
+ */
+static int load_module(struct load_info *info, const char __user *uargs,
+ int flags)
+{
+ struct module *mod;
+ long err = 0;
+ char *after_dashes;
+
+ /*
+ * Do the signature check (if any) first. All that
+ * the signature check needs is info->len, it does
+ * not need any of the section info. That can be
+ * set up later. This will minimize the chances
+ * of a corrupt module causing problems before
+ * we even get to the signature check.
+ *
+ * The check will also adjust info->len by stripping
+ * off the sig length at the end of the module, making
+ * checks against info->len more correct.
+ */
+ err = module_sig_check(info, flags);
+ if (err)
+ goto free_copy;
+
+ /*
+ * Do basic sanity checks against the ELF header and
+ * sections.
+ */
+ err = elf_validity_check(info);
+ if (err)
+ goto free_copy;
+
+ /*
+ * Everything checks out, so set up the section info
+ * in the info structure.
+ */
+ err = setup_load_info(info, flags);
+ if (err)
+ goto free_copy;
+
+ /*
+ * Now that we know we have the correct module name, check
+ * if it's blacklisted.
+ */
+ if (blacklisted(info->name)) {
+ err = -EPERM;
+ pr_err("Module %s is blacklisted\n", info->name);
+ goto free_copy;
+ }
+
+ err = rewrite_section_headers(info, flags);
+ if (err)
+ goto free_copy;
+
+ /* Check module struct version now, before we try to use module. */
+ if (!check_modstruct_version(info, info->mod)) {
+ err = -ENOEXEC;
+ goto free_copy;
+ }
+
+ /* Figure out module layout, and allocate all the memory. */
+ mod = layout_and_allocate(info, flags);
+ if (IS_ERR(mod)) {
+ err = PTR_ERR(mod);
+ goto free_copy;
+ }
+
+ audit_log_kern_module(mod->name);
+
+ /* Reserve our place in the list. */
+ err = add_unformed_module(mod);
+ if (err)
+ goto free_module;
+
+#ifdef CONFIG_MODULE_SIG
+ mod->sig_ok = info->sig_ok;
+ if (!mod->sig_ok) {
+ pr_notice_once("%s: module verification failed: signature "
+ "and/or required key missing - tainting "
+ "kernel\n", mod->name);
+ add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
+ }
+#endif
+
+ /* To avoid stressing percpu allocator, do this once we're unique. */
+ err = percpu_modalloc(mod, info);
+ if (err)
+ goto unlink_mod;
+
+ /* Now module is in final location, initialize linked lists, etc. */
+ err = module_unload_init(mod);
+ if (err)
+ goto unlink_mod;
+
+ init_param_lock(mod);
+
+ /*
+ * Now we've got everything in the final locations, we can
+ * find optional sections.
+ */
+ err = find_module_sections(mod, info);
+ if (err)
+ goto free_unload;
+
+ err = check_module_license_and_versions(mod);
+ if (err)
+ goto free_unload;
+
+ /* Set up MODINFO_ATTR fields */
+ setup_modinfo(mod, info);
+
+ /* Fix up syms, so that st_value is a pointer to location. */
+ err = simplify_symbols(mod, info);
+ if (err < 0)
+ goto free_modinfo;
+
+ err = apply_relocations(mod, info);
+ if (err < 0)
+ goto free_modinfo;
+
+ err = post_relocation(mod, info);
+ if (err < 0)
+ goto free_modinfo;
+
+ flush_module_icache(mod);
+
+ /* Setup CFI for the module. */
+ cfi_init(mod);
+
+ /* Now copy in args */
+ mod->args = strndup_user(uargs, ~0UL >> 1);
+ if (IS_ERR(mod->args)) {
+ err = PTR_ERR(mod->args);
+ goto free_arch_cleanup;
+ }
+
+ init_build_id(mod, info);
+ dynamic_debug_setup(mod, info->debug, info->num_debug);
+
+ /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
+ ftrace_module_init(mod);
+
+ /* Finally it's fully formed, ready to start executing. */
+ err = complete_formation(mod, info);
+ if (err)
+ goto ddebug_cleanup;
+
+ err = prepare_coming_module(mod);
+ if (err)
+ goto bug_cleanup;
+
+ /* Module is ready to execute: parsing args may do that. */
+ after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
+ -32768, 32767, mod,
+ unknown_module_param_cb);
+ if (IS_ERR(after_dashes)) {
+ err = PTR_ERR(after_dashes);
+ goto coming_cleanup;
+ } else if (after_dashes) {
+ pr_warn("%s: parameters '%s' after `--' ignored\n",
+ mod->name, after_dashes);
+ }
+
+ /* Link in to sysfs. */
+ err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
+ if (err < 0)
+ goto coming_cleanup;
+
+ if (is_livepatch_module(mod)) {
+ err = copy_module_elf(mod, info);
+ if (err < 0)
+ goto sysfs_cleanup;
+ }
+
+ /* Get rid of temporary copy. */
+ free_copy(info, flags);
+
+ /* Done! */
+ trace_module_load(mod);
+
+ return do_init_module(mod);
+
+ sysfs_cleanup:
+ mod_sysfs_teardown(mod);
+ coming_cleanup:
+ mod->state = MODULE_STATE_GOING;
+ destroy_params(mod->kp, mod->num_kp);
+ blocking_notifier_call_chain(&module_notify_list,
+ MODULE_STATE_GOING, mod);
+ klp_module_going(mod);
+ bug_cleanup:
+ mod->state = MODULE_STATE_GOING;
+ /* module_bug_cleanup needs module_mutex protection */
+ mutex_lock(&module_mutex);
+ module_bug_cleanup(mod);
+ mutex_unlock(&module_mutex);
+
+ ddebug_cleanup:
+ ftrace_release_mod(mod);
+ dynamic_debug_remove(mod, info->debug);
+ synchronize_rcu();
+ kfree(mod->args);
+ free_arch_cleanup:
+ cfi_cleanup(mod);
+ module_arch_cleanup(mod);
+ free_modinfo:
+ free_modinfo(mod);
+ free_unload:
+ module_unload_free(mod);
+ unlink_mod:
+ mutex_lock(&module_mutex);
+ /* Unlink carefully: kallsyms could be walking list. */
+ list_del_rcu(&mod->list);
+ mod_tree_remove(mod);
+ wake_up_all(&module_wq);
+ /* Wait for RCU-sched synchronizing before releasing mod->list. */
+ synchronize_rcu();
+ mutex_unlock(&module_mutex);
+ free_module:
+ /* Free lock-classes; relies on the preceding sync_rcu() */
+ lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
+
+ module_deallocate(mod, info);
+ free_copy:
+ free_copy(info, flags);
+ return err;
+}
+
+SYSCALL_DEFINE3(init_module, void __user *, umod,
+ unsigned long, len, const char __user *, uargs)
+{
+ int err;
+ struct load_info info = { };
+
+ err = may_init_module();
+ if (err)
+ return err;
+
+ pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
+ umod, len, uargs);
+
+ err = copy_module_from_user(umod, len, &info);
+ if (err)
+ return err;
+
+ return load_module(&info, uargs, 0);
+}
+
+SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
+{
+ struct load_info info = { };
+ void *buf = NULL;
+ int len;
+ int err;
+
+ err = may_init_module();
+ if (err)
+ return err;
+
+ pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
+
+ if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
+ |MODULE_INIT_IGNORE_VERMAGIC
+ |MODULE_INIT_COMPRESSED_FILE))
+ return -EINVAL;
+
+ len = kernel_read_file_from_fd(fd, 0, &buf, INT_MAX, NULL,
+ READING_MODULE);
+ if (len < 0)
+ return len;
+
+ if (flags & MODULE_INIT_COMPRESSED_FILE) {
+ err = module_decompress(&info, buf, len);
+ vfree(buf); /* compressed data is no longer needed */
+ if (err)
+ return err;
+ } else {
+ info.hdr = buf;
+ info.len = len;
+ }
+
+ return load_module(&info, uargs, flags);
+}
+
+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;
+
+ cond_resched();
+ }
+ }
+out:
+ mutex_unlock(&module_mutex);
+ return ret;
+}
+#endif /* CONFIG_LIVEPATCH */
+#endif /* CONFIG_KALLSYMS */
+
+static void cfi_init(struct module *mod)
+{
+#ifdef CONFIG_CFI_CLANG
+ initcall_t *init;
+ exitcall_t *exit;
+
+ rcu_read_lock_sched();
+ mod->cfi_check = (cfi_check_fn)
+ find_kallsyms_symbol_value(mod, "__cfi_check");
+ init = (initcall_t *)
+ find_kallsyms_symbol_value(mod, "__cfi_jt_init_module");
+ exit = (exitcall_t *)
+ find_kallsyms_symbol_value(mod, "__cfi_jt_cleanup_module");
+ rcu_read_unlock_sched();
+
+ /* Fix init/exit functions to point to the CFI jump table */
+ if (init)
+ mod->init = *init;
+#ifdef CONFIG_MODULE_UNLOAD
+ if (exit)
+ mod->exit = *exit;
+#endif
+
+ cfi_module_add(mod, module_addr_min);
+#endif
+}
+
+static void cfi_cleanup(struct module *mod)
+{
+#ifdef CONFIG_CFI_CLANG
+ cfi_module_remove(mod, module_addr_min);
+#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)
+{
+ int bx = 0;
+
+ BUG_ON(mod->state == MODULE_STATE_UNFORMED);
+ if (mod->taints ||
+ mod->state == MODULE_STATE_GOING ||
+ mod->state == MODULE_STATE_COMING) {
+ buf[bx++] = '(';
+ bx += module_flags_taint(mod, buf + bx);
+ /* Show a - for module-is-being-unloaded */
+ if (mod->state == MODULE_STATE_GOING)
+ buf[bx++] = '-';
+ /* Show a + for module-is-being-loaded */
+ if (mod->state == MODULE_STATE_COMING)
+ buf[bx++] = '+';
+ buf[bx++] = ')';
+ }
+ buf[bx] = '\0';
+
+ 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)
+{
+ const struct exception_table_entry *e = NULL;
+ struct module *mod;
+
+ preempt_disable();
+ mod = __module_address(addr);
+ if (!mod)
+ goto out;
+
+ if (!mod->num_exentries)
+ goto out;
+
+ e = search_extable(mod->extable,
+ mod->num_exentries,
+ addr);
+out:
+ preempt_enable();
+
+ /*
+ * Now, if we found one, we are running inside it now, hence
+ * we cannot unload the module, hence no refcnt needed.
+ */
+ return e;
+}
+
+/**
+ * is_module_address() - is this address inside a module?
+ * @addr: the address to check.
+ *
+ * See is_module_text_address() if you simply want to see if the address
+ * is code (not data).
+ */
+bool is_module_address(unsigned long addr)
+{
+ bool ret;
+
+ preempt_disable();
+ ret = __module_address(addr) != NULL;
+ preempt_enable();
+
+ return ret;
+}
+
+/**
+ * __module_address() - get the module which contains an address.
+ * @addr: the address.
+ *
+ * Must be called with preempt disabled or module mutex held so that
+ * module doesn't get freed during this.
+ */
+struct module *__module_address(unsigned long addr)
+{
+ struct module *mod;
+
+ if (addr < module_addr_min || addr > module_addr_max)
+ return NULL;
+
+ module_assert_mutex_or_preempt();
+
+ mod = mod_find(addr);
+ if (mod) {
+ BUG_ON(!within_module(addr, mod));
+ if (mod->state == MODULE_STATE_UNFORMED)
+ mod = NULL;
+ }
+ return mod;
+}
+
+/**
+ * is_module_text_address() - is this address inside module code?
+ * @addr: the address to check.
+ *
+ * See is_module_address() if you simply want to see if the address is
+ * anywhere in a module. See kernel_text_address() for testing if an
+ * address corresponds to kernel or module code.
+ */
+bool is_module_text_address(unsigned long addr)
+{
+ bool ret;
+
+ preempt_disable();
+ ret = __module_text_address(addr) != NULL;
+ preempt_enable();
+
+ return ret;
+}
+
+/**
+ * __module_text_address() - get the module whose code contains an address.
+ * @addr: the address.
+ *
+ * Must be called with preempt disabled or module mutex held so that
+ * module doesn't get freed during this.
+ */
+struct module *__module_text_address(unsigned long addr)
+{
+ struct module *mod = __module_address(addr);
+ if (mod) {
+ /* Make sure it's within the text section. */
+ if (!within(addr, mod->init_layout.base, mod->init_layout.text_size)
+ && !within(addr, mod->core_layout.base, mod->core_layout.text_size))
+ mod = NULL;
+ }
+ return mod;
+}
+
+/* Don't grab lock, we're oopsing. */
+void print_modules(void)
+{
+ struct module *mod;
+ char buf[MODULE_FLAGS_BUF_SIZE];
+
+ printk(KERN_DEFAULT "Modules linked in:");
+ /* Most callers should already have preempt disabled, but make sure */
+ preempt_disable();
+ list_for_each_entry_rcu(mod, &modules, list) {
+ if (mod->state == MODULE_STATE_UNFORMED)
+ continue;
+ pr_cont(" %s%s", mod->name, module_flags(mod, buf));
+ }
+ preempt_enable();
+ if (last_unloaded_module[0])
+ 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/signing.c b/kernel/module/signing.c
new file mode 100644
index 000000000000..8aeb6d2ee94b
--- /dev/null
+++ b/kernel/module/signing.c
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Module signature checker
+ *
+ * Copyright (C) 2012 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <linux/module_signature.h>
+#include <linux/string.h>
+#include <linux/verification.h>
+#include <crypto/public_key.h>
+#include "internal.h"
+
+/*
+ * Verify the signature on a module.
+ */
+int mod_verify_sig(const void *mod, struct load_info *info)
+{
+ struct module_signature ms;
+ size_t sig_len, modlen = info->len;
+ int ret;
+
+ pr_devel("==>%s(,%zu)\n", __func__, modlen);
+
+ if (modlen <= sizeof(ms))
+ return -EBADMSG;
+
+ memcpy(&ms, mod + (modlen - sizeof(ms)), sizeof(ms));
+
+ ret = mod_check_sig(&ms, modlen, "module");
+ if (ret)
+ return ret;
+
+ sig_len = be32_to_cpu(ms.sig_len);
+ modlen -= sig_len + sizeof(ms);
+ info->len = modlen;
+
+ return verify_pkcs7_signature(mod, modlen, mod + modlen, sig_len,
+ VERIFY_USE_SECONDARY_KEYRING,
+ VERIFYING_MODULE_SIGNATURE,
+ NULL, NULL);
+}