module.c 83.7 KB
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/*
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   Copyright (C) 2002 Richard Henderson
   Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
#include <linux/module.h>
#include <linux/moduleloader.h>
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#include <linux/ftrace_event.h>
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#include <linux/init.h>
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#include <linux/kallsyms.h>
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#include <linux/fs.h>
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#include <linux/sysfs.h>
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#include <linux/kernel.h>
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#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/elf.h>
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#include <linux/proc_fs.h>
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#include <linux/seq_file.h>
#include <linux/syscalls.h>
#include <linux/fcntl.h>
#include <linux/rcupdate.h>
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#include <linux/capability.h>
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#include <linux/cpu.h>
#include <linux/moduleparam.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/vermagic.h>
#include <linux/notifier.h>
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#include <linux/sched.h>
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#include <linux/stop_machine.h>
#include <linux/device.h>
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#include <linux/string.h>
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#include <linux/mutex.h>
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#include <linux/rculist.h>
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#include <asm/uaccess.h>
#include <asm/cacheflush.h>
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#include <asm/mmu_context.h>
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#include <linux/license.h>
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#include <asm/sections.h>
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#include <linux/tracepoint.h>
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#include <linux/ftrace.h>
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#include <linux/async.h>
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#include <linux/percpu.h>
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#include <linux/kmemleak.h>
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#define CREATE_TRACE_POINTS
#include <trace/events/module.h>

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#if 0
#define DEBUGP printk
#else
#define DEBUGP(fmt , a...)
#endif

#ifndef ARCH_SHF_SMALL
#define ARCH_SHF_SMALL 0
#endif

/* If this is set, the section belongs in the init part of the module */
#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))

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/*
 * Mutex protects:
 * 1) List of modules (also safely readable with preempt_disable),
 * 2) module_use links,
 * 3) module_addr_min/module_addr_max.
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 * (delete uses stop_machine/add uses RCU list operations). */
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DEFINE_MUTEX(module_mutex);
EXPORT_SYMBOL_GPL(module_mutex);
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static LIST_HEAD(modules);
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#ifdef CONFIG_KGDB_KDB
struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
#endif /* CONFIG_KGDB_KDB */

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/* Block module loading/unloading? */
int modules_disabled = 0;

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/* Waiting for a module to finish initializing? */
static DECLARE_WAIT_QUEUE_HEAD(module_wq);

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static BLOCKING_NOTIFIER_HEAD(module_notify_list);
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/* Bounds of module allocation, for speeding __module_address.
 * Protected by module_mutex. */
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static unsigned long module_addr_min = -1UL, module_addr_max = 0;

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int register_module_notifier(struct notifier_block * nb)
{
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	return blocking_notifier_chain_register(&module_notify_list, nb);
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}
EXPORT_SYMBOL(register_module_notifier);

int unregister_module_notifier(struct notifier_block * nb)
{
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	return blocking_notifier_chain_unregister(&module_notify_list, nb);
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}
EXPORT_SYMBOL(unregister_module_notifier);

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/* We require a truly strong try_module_get(): 0 means failure due to
   ongoing or failed initialization etc. */
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static inline int strong_try_module_get(struct module *mod)
{
	if (mod && mod->state == MODULE_STATE_COMING)
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		return -EBUSY;
	if (try_module_get(mod))
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		return 0;
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	else
		return -ENOENT;
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}

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static inline void add_taint_module(struct module *mod, unsigned flag)
{
	add_taint(flag);
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	mod->taints |= (1U << flag);
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}

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/*
 * A thread that wants to hold a reference to a module only while it
 * is running can call this to safely exit.  nfsd and lockd use this.
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 */
void __module_put_and_exit(struct module *mod, long code)
{
	module_put(mod);
	do_exit(code);
}
EXPORT_SYMBOL(__module_put_and_exit);
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/* Find a module section: 0 means not found. */
static unsigned int find_sec(Elf_Ehdr *hdr,
			     Elf_Shdr *sechdrs,
			     const char *secstrings,
			     const char *name)
{
	unsigned int i;

	for (i = 1; i < hdr->e_shnum; i++)
		/* Alloc bit cleared means "ignore it." */
		if ((sechdrs[i].sh_flags & SHF_ALLOC)
		    && strcmp(secstrings+sechdrs[i].sh_name, name) == 0)
			return i;
	return 0;
}

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/* Find a module section, or NULL. */
static void *section_addr(Elf_Ehdr *hdr, Elf_Shdr *shdrs,
			  const char *secstrings, const char *name)
{
	/* Section 0 has sh_addr 0. */
	return (void *)shdrs[find_sec(hdr, shdrs, secstrings, name)].sh_addr;
}

/* Find a module section, or NULL.  Fill in number of "objects" in section. */
static void *section_objs(Elf_Ehdr *hdr,
			  Elf_Shdr *sechdrs,
			  const char *secstrings,
			  const char *name,
			  size_t object_size,
			  unsigned int *num)
{
	unsigned int sec = find_sec(hdr, sechdrs, secstrings, name);

	/* Section 0 has sh_addr 0 and sh_size 0. */
	*num = sechdrs[sec].sh_size / object_size;
	return (void *)sechdrs[sec].sh_addr;
}

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/* 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[];
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extern const struct kernel_symbol __start___ksymtab_gpl_future[];
extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
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extern const unsigned long __start___kcrctab[];
extern const unsigned long __start___kcrctab_gpl[];
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extern const unsigned long __start___kcrctab_gpl_future[];
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#ifdef CONFIG_UNUSED_SYMBOLS
extern const struct kernel_symbol __start___ksymtab_unused[];
extern const struct kernel_symbol __stop___ksymtab_unused[];
extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
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extern const unsigned long __start___kcrctab_unused[];
extern const unsigned long __start___kcrctab_unused_gpl[];
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#endif
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#ifndef CONFIG_MODVERSIONS
#define symversion(base, idx) NULL
#else
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#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
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#endif

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static bool each_symbol_in_section(const struct symsearch *arr,
				   unsigned int arrsize,
				   struct module *owner,
				   bool (*fn)(const struct symsearch *syms,
					      struct module *owner,
					      unsigned int symnum, void *data),
				   void *data)
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{
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	unsigned int i, j;
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	for (j = 0; j < arrsize; j++) {
		for (i = 0; i < arr[j].stop - arr[j].start; i++)
			if (fn(&arr[j], owner, i, data))
				return true;
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	}
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	return false;
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}

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/* Returns true as soon as fn returns true, otherwise false. */
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bool each_symbol(bool (*fn)(const struct symsearch *arr, struct module *owner,
			    unsigned int symnum, void *data), void *data)
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{
	struct module *mod;
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	static const struct symsearch arr[] = {
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		{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
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		  NOT_GPL_ONLY, false },
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		{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
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		  __start___kcrctab_gpl,
		  GPL_ONLY, false },
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		{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
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		  __start___kcrctab_gpl_future,
		  WILL_BE_GPL_ONLY, false },
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#ifdef CONFIG_UNUSED_SYMBOLS
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		{ __start___ksymtab_unused, __stop___ksymtab_unused,
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		  __start___kcrctab_unused,
		  NOT_GPL_ONLY, true },
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		{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
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		  __start___kcrctab_unused_gpl,
		  GPL_ONLY, true },
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#endif
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	};
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	if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
		return true;
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	list_for_each_entry_rcu(mod, &modules, list) {
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		struct symsearch arr[] = {
			{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
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			  NOT_GPL_ONLY, false },
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			{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
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			  mod->gpl_crcs,
			  GPL_ONLY, false },
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			{ mod->gpl_future_syms,
			  mod->gpl_future_syms + mod->num_gpl_future_syms,
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			  mod->gpl_future_crcs,
			  WILL_BE_GPL_ONLY, false },
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#ifdef CONFIG_UNUSED_SYMBOLS
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			{ mod->unused_syms,
			  mod->unused_syms + mod->num_unused_syms,
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			  mod->unused_crcs,
			  NOT_GPL_ONLY, true },
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			{ mod->unused_gpl_syms,
			  mod->unused_gpl_syms + mod->num_unused_gpl_syms,
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			  mod->unused_gpl_crcs,
			  GPL_ONLY, true },
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#endif
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		};

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		if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
			return true;
	}
	return false;
}
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EXPORT_SYMBOL_GPL(each_symbol);
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struct find_symbol_arg {
	/* Input */
	const char *name;
	bool gplok;
	bool warn;

	/* Output */
	struct module *owner;
	const unsigned long *crc;
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	const struct kernel_symbol *sym;
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};

static bool find_symbol_in_section(const struct symsearch *syms,
				   struct module *owner,
				   unsigned int symnum, void *data)
{
	struct find_symbol_arg *fsa = data;

	if (strcmp(syms->start[symnum].name, fsa->name) != 0)
		return false;

	if (!fsa->gplok) {
		if (syms->licence == GPL_ONLY)
			return false;
		if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
			printk(KERN_WARNING "Symbol %s is being used "
			       "by a non-GPL module, which will not "
			       "be allowed in the future\n", fsa->name);
			printk(KERN_WARNING "Please see the file "
			       "Documentation/feature-removal-schedule.txt "
			       "in the kernel source tree for more details.\n");
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		}
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	}
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#ifdef CONFIG_UNUSED_SYMBOLS
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	if (syms->unused && fsa->warn) {
		printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
		       "however this module is using it.\n", fsa->name);
		printk(KERN_WARNING
		       "This symbol will go away in the future.\n");
		printk(KERN_WARNING
		       "Please evalute if this is the right api to use and if "
		       "it really is, submit a report the linux kernel "
		       "mailinglist together with submitting your code for "
		       "inclusion.\n");
	}
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#endif
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	fsa->owner = owner;
	fsa->crc = symversion(syms->crcs, symnum);
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	fsa->sym = &syms->start[symnum];
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	return true;
}

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/* Find a symbol and return it, along with, (optional) crc and
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 * (optional) module which owns it.  Needs preempt disabled or module_mutex. */
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const struct kernel_symbol *find_symbol(const char *name,
					struct module **owner,
					const unsigned long **crc,
					bool gplok,
					bool warn)
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{
	struct find_symbol_arg fsa;

	fsa.name = name;
	fsa.gplok = gplok;
	fsa.warn = warn;

	if (each_symbol(find_symbol_in_section, &fsa)) {
		if (owner)
			*owner = fsa.owner;
		if (crc)
			*crc = fsa.crc;
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		return fsa.sym;
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	}

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	DEBUGP("Failed to find symbol %s\n", name);
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	return NULL;
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}
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EXPORT_SYMBOL_GPL(find_symbol);
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/* Search for module by name: must hold module_mutex. */
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struct module *find_module(const char *name)
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{
	struct module *mod;

	list_for_each_entry(mod, &modules, list) {
		if (strcmp(mod->name, name) == 0)
			return mod;
	}
	return NULL;
}
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EXPORT_SYMBOL_GPL(find_module);
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#ifdef CONFIG_SMP
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static inline void __percpu *mod_percpu(struct module *mod)
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{
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	return mod->percpu;
}
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static int percpu_modalloc(struct module *mod,
			   unsigned long size, unsigned long align)
{
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	if (align > PAGE_SIZE) {
		printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n",
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		       mod->name, align, PAGE_SIZE);
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		align = PAGE_SIZE;
	}

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	mod->percpu = __alloc_reserved_percpu(size, align);
	if (!mod->percpu) {
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		printk(KERN_WARNING
		       "Could not allocate %lu bytes percpu data\n", size);
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		return -ENOMEM;
	}
	mod->percpu_size = size;
	return 0;
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}

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static void percpu_modfree(struct module *mod)
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{
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	free_percpu(mod->percpu);
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}

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static unsigned int find_pcpusec(Elf_Ehdr *hdr,
				 Elf_Shdr *sechdrs,
				 const char *secstrings)
{
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	return find_sec(hdr, sechdrs, secstrings, ".data..percpu");
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}

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static void percpu_modcopy(struct module *mod,
			   const void *from, unsigned long size)
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{
	int cpu;

	for_each_possible_cpu(cpu)
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		memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
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}

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/**
 * 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.
 *
 * RETURNS:
 * %true if @addr is from module static percpu area
 */
bool is_module_percpu_address(unsigned long addr)
{
	struct module *mod;
	unsigned int cpu;

	preempt_disable();

	list_for_each_entry_rcu(mod, &modules, list) {
		if (!mod->percpu_size)
			continue;
		for_each_possible_cpu(cpu) {
			void *start = per_cpu_ptr(mod->percpu, cpu);

			if ((void *)addr >= start &&
			    (void *)addr < start + mod->percpu_size) {
				preempt_enable();
				return true;
			}
		}
	}

	preempt_enable();
	return false;
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}

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#else /* ... !CONFIG_SMP */
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static inline void __percpu *mod_percpu(struct module *mod)
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{
	return NULL;
}
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static inline int percpu_modalloc(struct module *mod,
				  unsigned long size, unsigned long align)
{
	return -ENOMEM;
}
static inline void percpu_modfree(struct module *mod)
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{
}
static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
					Elf_Shdr *sechdrs,
					const char *secstrings)
{
	return 0;
}
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static inline void percpu_modcopy(struct module *mod,
				  const void *from, unsigned long size)
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{
	/* pcpusec should be 0, and size of that section should be 0. */
	BUG_ON(size != 0);
}
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bool is_module_percpu_address(unsigned long addr)
{
	return false;
}
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#endif /* CONFIG_SMP */

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#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 *mod, char *buffer)             \
{                                                                     \
	return sprintf(buffer, "%s\n", mod->field);                   \
}                                                                     \
static int modinfo_##field##_exists(struct module *mod)               \
{                                                                     \
	return mod->field != NULL;                                    \
}                                                                     \
static void free_modinfo_##field(struct module *mod)                  \
{                                                                     \
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	kfree(mod->field);                                            \
	mod->field = NULL;                                            \
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}                                                                     \
static struct module_attribute modinfo_##field = {                    \
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	.attr = { .name = __stringify(field), .mode = 0444 },         \
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	.show = show_modinfo_##field,                                 \
	.setup = setup_modinfo_##field,                               \
	.test = modinfo_##field##_exists,                             \
	.free = free_modinfo_##field,                                 \
};

MODINFO_ATTR(version);
MODINFO_ATTR(srcversion);

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static char last_unloaded_module[MODULE_NAME_LEN+1];

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#ifdef CONFIG_MODULE_UNLOAD
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EXPORT_TRACEPOINT_SYMBOL(module_get);

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/* Init the unload section of the module. */
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static int module_unload_init(struct module *mod)
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{
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	mod->refptr = alloc_percpu(struct module_ref);
	if (!mod->refptr)
		return -ENOMEM;

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	INIT_LIST_HEAD(&mod->source_list);
	INIT_LIST_HEAD(&mod->target_list);
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	/* Hold reference count during initialization. */
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	__this_cpu_write(mod->refptr->incs, 1);
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	/* Backwards compatibility macros put refcount during init. */
	mod->waiter = current;
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	return 0;
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}

/* Does a already use b? */
static int already_uses(struct module *a, struct module *b)
{
	struct module_use *use;

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	list_for_each_entry(use, &b->source_list, source_list) {
		if (use->source == a) {
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			DEBUGP("%s uses %s!\n", a->name, b->name);
			return 1;
		}
	}
	DEBUGP("%s does not use %s!\n", a->name, b->name);
	return 0;
}

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/*
 * 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;

	DEBUGP("Allocating new usage for %s.\n", a->name);
	use = kmalloc(sizeof(*use), GFP_ATOMIC);
	if (!use) {
		printk(KERN_WARNING "%s: out of memory loading\n", a->name);
		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;
}

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/* Module a uses b: caller needs module_mutex() */
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int ref_module(struct module *a, struct module *b)
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{
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	int err;
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	if (b == NULL || already_uses(a, b))
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		return 0;

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	/* If module isn't available, we fail. */
	err = strong_try_module_get(b);
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	if (err)
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		return err;
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	err = add_module_usage(a, b);
	if (err) {
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		module_put(b);
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		return err;
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	}
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	return 0;
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}
604
EXPORT_SYMBOL_GPL(ref_module);
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/* Clear the unload stuff of the module. */
static void module_unload_free(struct module *mod)
{
609
	struct module_use *use, *tmp;
L
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610

611
	mutex_lock(&module_mutex);
612 613 614 615 616 617 618
	list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
		struct module *i = use->target;
		DEBUGP("%s unusing %s\n", mod->name, i->name);
		module_put(i);
		list_del(&use->source_list);
		list_del(&use->target_list);
		kfree(use);
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619
	}
620
	mutex_unlock(&module_mutex);
621 622

	free_percpu(mod->refptr);
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}

#ifdef CONFIG_MODULE_FORCE_UNLOAD
626
static inline int try_force_unload(unsigned int flags)
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627 628 629
{
	int ret = (flags & O_TRUNC);
	if (ret)
630
		add_taint(TAINT_FORCED_RMMOD);
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	return ret;
}
#else
634
static inline int try_force_unload(unsigned int flags)
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{
	return 0;
}
#endif /* CONFIG_MODULE_FORCE_UNLOAD */

struct stopref
{
	struct module *mod;
	int flags;
	int *forced;
};

/* Whole machine is stopped with interrupts off when this runs. */
static int __try_stop_module(void *_sref)
{
	struct stopref *sref = _sref;

652 653
	/* If it's not unused, quit unless we're forcing. */
	if (module_refcount(sref->mod) != 0) {
654
		if (!(*sref->forced = try_force_unload(sref->flags)))
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			return -EWOULDBLOCK;
	}

	/* Mark it as dying. */
	sref->mod->state = MODULE_STATE_GOING;
	return 0;
}

static int try_stop_module(struct module *mod, int flags, int *forced)
{
665 666
	if (flags & O_NONBLOCK) {
		struct stopref sref = { mod, flags, forced };
L
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668
		return stop_machine(__try_stop_module, &sref, NULL);
669 670 671 672 673 674
	} else {
		/* We don't need to stop the machine for this. */
		mod->state = MODULE_STATE_GOING;
		synchronize_sched();
		return 0;
	}
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}

unsigned int module_refcount(struct module *mod)
{
679
	unsigned int incs = 0, decs = 0;
680
	int cpu;
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682
	for_each_possible_cpu(cpu)
683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700
		decs += per_cpu_ptr(mod->refptr, cpu)->decs;
	/*
	 * ensure the incs are added up after the decs.
	 * module_put ensures incs are visible before decs with smp_wmb.
	 *
	 * This 2-count scheme avoids the situation where the refcount
	 * for CPU0 is read, then CPU0 increments the module refcount,
	 * then CPU1 drops that refcount, then the refcount for CPU1 is
	 * read. We would record a decrement but not its corresponding
	 * increment so we would see a low count (disaster).
	 *
	 * Rare situation? But module_refcount can be preempted, and we
	 * might be tallying up 4096+ CPUs. So it is not impossible.
	 */
	smp_rmb();
	for_each_possible_cpu(cpu)
		incs += per_cpu_ptr(mod->refptr, cpu)->incs;
	return incs - decs;
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}
EXPORT_SYMBOL(module_refcount);

/* This exists whether we can unload or not */
static void free_module(struct module *mod);

static void wait_for_zero_refcount(struct module *mod)
{
709
	/* Since we might sleep for some time, release the mutex first */
710
	mutex_unlock(&module_mutex);
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	for (;;) {
		DEBUGP("Looking at refcount...\n");
		set_current_state(TASK_UNINTERRUPTIBLE);
		if (module_refcount(mod) == 0)
			break;
		schedule();
	}
	current->state = TASK_RUNNING;
719
	mutex_lock(&module_mutex);
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}

722 723
SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
		unsigned int, flags)
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{
	struct module *mod;
726
	char name[MODULE_NAME_LEN];
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	int ret, forced = 0;

729
	if (!capable(CAP_SYS_MODULE) || modules_disabled)
730 731 732 733 734 735
		return -EPERM;

	if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
		return -EFAULT;
	name[MODULE_NAME_LEN-1] = '\0';

736 737
	if (mutex_lock_interruptible(&module_mutex) != 0)
		return -EINTR;
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	mod = find_module(name);
	if (!mod) {
		ret = -ENOENT;
		goto out;
	}

745
	if (!list_empty(&mod->source_list)) {
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		/* 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 and wake up
                   waiter --RR */
		DEBUGP("%s already dying\n", mod->name);
		ret = -EBUSY;
		goto out;
	}

	/* If it has an init func, it must have an exit func to unload */
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	if (mod->init && !mod->exit) {
762
		forced = try_force_unload(flags);
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		if (!forced) {
			/* This module can't be removed */
			ret = -EBUSY;
			goto out;
		}
	}

	/* Set this up before setting mod->state */
	mod->waiter = current;

	/* Stop the machine so refcounts can't move and disable module. */
	ret = try_stop_module(mod, flags, &forced);
	if (ret != 0)
		goto out;

	/* Never wait if forced. */
	if (!forced && module_refcount(mod) != 0)
		wait_for_zero_refcount(mod);

782
	mutex_unlock(&module_mutex);
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	/* Final destruction now noone is using it. */
784
	if (mod->exit != NULL)
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		mod->exit();
786 787
	blocking_notifier_call_chain(&module_notify_list,
				     MODULE_STATE_GOING, mod);
788
	async_synchronize_full();
789

790
	/* Store the name of the last unloaded module for diagnostic purposes */
791
	strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
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792

793 794 795
	free_module(mod);
	return 0;
out:
796
	mutex_unlock(&module_mutex);
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797 798 799
	return ret;
}

800
static inline void print_unload_info(struct seq_file *m, struct module *mod)
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801 802 803 804 805 806 807 808
{
	struct module_use *use;
	int printed_something = 0;

	seq_printf(m, " %u ", module_refcount(mod));

	/* Always include a trailing , so userspace can differentiate
           between this and the old multi-field proc format. */
809
	list_for_each_entry(use, &mod->source_list, source_list) {
L
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810
		printed_something = 1;
811
		seq_printf(m, "%s,", use->source->name);
L
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812 813 814 815 816 817 818 819 820 821 822 823 824 825 826
	}

	if (mod->init != NULL && mod->exit == NULL) {
		printed_something = 1;
		seq_printf(m, "[permanent],");
	}

	if (!printed_something)
		seq_printf(m, "-");
}

void __symbol_put(const char *symbol)
{
	struct module *owner;

R
Rusty Russell 已提交
827
	preempt_disable();
828
	if (!find_symbol(symbol, &owner, NULL, true, false))
L
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829 830
		BUG();
	module_put(owner);
R
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831
	preempt_enable();
L
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832 833 834
}
EXPORT_SYMBOL(__symbol_put);

835
/* Note this assumes addr is a function, which it currently always is. */
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836 837
void symbol_put_addr(void *addr)
{
838
	struct module *modaddr;
839
	unsigned long a = (unsigned long)dereference_function_descriptor(addr);
L
Linus Torvalds 已提交
840

841
	if (core_kernel_text(a))
842
		return;
L
Linus Torvalds 已提交
843

844 845
	/* module_text_address is safe here: we're supposed to have reference
	 * to module from symbol_get, so it can't go away. */
846
	modaddr = __module_text_address(a);
847
	BUG_ON(!modaddr);
848
	module_put(modaddr);
L
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849 850 851 852 853 854
}
EXPORT_SYMBOL_GPL(symbol_put_addr);

static ssize_t show_refcnt(struct module_attribute *mattr,
			   struct module *mod, char *buffer)
{
855
	return sprintf(buffer, "%u\n", module_refcount(mod));
L
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856 857 858
}

static struct module_attribute refcnt = {
859
	.attr = { .name = "refcnt", .mode = 0444 },
L
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860 861 862
	.show = show_refcnt,
};

A
Al Viro 已提交
863 864 865
void module_put(struct module *module)
{
	if (module) {
866
		preempt_disable();
867 868
		smp_wmb(); /* see comment in module_refcount */
		__this_cpu_inc(module->refptr->decs);
869

870
		trace_module_put(module, _RET_IP_);
A
Al Viro 已提交
871 872 873
		/* Maybe they're waiting for us to drop reference? */
		if (unlikely(!module_is_live(module)))
			wake_up_process(module->waiter);
874
		preempt_enable();
A
Al Viro 已提交
875 876 877 878
	}
}
EXPORT_SYMBOL(module_put);

L
Linus Torvalds 已提交
879
#else /* !CONFIG_MODULE_UNLOAD */
880
static inline void print_unload_info(struct seq_file *m, struct module *mod)
L
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881 882 883 884 885 886 887 888 889
{
	/* We don't know the usage count, or what modules are using. */
	seq_printf(m, " - -");
}

static inline void module_unload_free(struct module *mod)
{
}

890
int ref_module(struct module *a, struct module *b)
L
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891
{
892
	return strong_try_module_get(b);
L
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893
}
894
EXPORT_SYMBOL_GPL(ref_module);
L
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895

896
static inline int module_unload_init(struct module *mod)
L
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897
{
898
	return 0;
L
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899 900 901
}
#endif /* CONFIG_MODULE_UNLOAD */

902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921
static ssize_t show_initstate(struct module_attribute *mattr,
			   struct module *mod, char *buffer)
{
	const char *state = "unknown";

	switch (mod->state) {
	case MODULE_STATE_LIVE:
		state = "live";
		break;
	case MODULE_STATE_COMING:
		state = "coming";
		break;
	case MODULE_STATE_GOING:
		state = "going";
		break;
	}
	return sprintf(buffer, "%s\n", state);
}

static struct module_attribute initstate = {
922
	.attr = { .name = "initstate", .mode = 0444 },
923 924 925
	.show = show_initstate,
};

926 927 928
static struct module_attribute *modinfo_attrs[] = {
	&modinfo_version,
	&modinfo_srcversion,
929
	&initstate,
930 931 932 933 934 935
#ifdef CONFIG_MODULE_UNLOAD
	&refcnt,
#endif
	NULL,
};

L
Linus Torvalds 已提交
936 937
static const char vermagic[] = VERMAGIC_STRING;

938
static int try_to_force_load(struct module *mod, const char *reason)
939 940
{
#ifdef CONFIG_MODULE_FORCE_LOAD
A
Andi Kleen 已提交
941
	if (!test_taint(TAINT_FORCED_MODULE))
942 943
		printk(KERN_WARNING "%s: %s: kernel tainted.\n",
		       mod->name, reason);
944 945 946 947 948 949 950
	add_taint_module(mod, TAINT_FORCED_MODULE);
	return 0;
#else
	return -ENOEXEC;
#endif
}

L
Linus Torvalds 已提交
951
#ifdef CONFIG_MODVERSIONS
952 953 954 955 956 957 958 959 960 961 962
/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */
static unsigned long maybe_relocated(unsigned long crc,
				     const struct module *crc_owner)
{
#ifdef ARCH_RELOCATES_KCRCTAB
	if (crc_owner == NULL)
		return crc - (unsigned long)reloc_start;
#endif
	return crc;
}

L
Linus Torvalds 已提交
963 964 965 966
static int check_version(Elf_Shdr *sechdrs,
			 unsigned int versindex,
			 const char *symname,
			 struct module *mod, 
967 968
			 const unsigned long *crc,
			 const struct module *crc_owner)
L
Linus Torvalds 已提交
969 970 971 972 973 974 975 976
{
	unsigned int i, num_versions;
	struct modversion_info *versions;

	/* Exporting module didn't supply crcs?  OK, we're already tainted. */
	if (!crc)
		return 1;

977 978 979 980
	/* No versions at all?  modprobe --force does this. */
	if (versindex == 0)
		return try_to_force_load(mod, symname) == 0;

L
Linus Torvalds 已提交
981 982 983 984 985 986 987 988
	versions = (void *) sechdrs[versindex].sh_addr;
	num_versions = sechdrs[versindex].sh_size
		/ sizeof(struct modversion_info);

	for (i = 0; i < num_versions; i++) {
		if (strcmp(versions[i].name, symname) != 0)
			continue;

989
		if (versions[i].crc == maybe_relocated(*crc, crc_owner))
L
Linus Torvalds 已提交
990 991
			return 1;
		DEBUGP("Found checksum %lX vs module %lX\n",
992
		       maybe_relocated(*crc, crc_owner), versions[i].crc);
993
		goto bad_version;
L
Linus Torvalds 已提交
994
	}
995

996 997 998
	printk(KERN_WARNING "%s: no symbol version for %s\n",
	       mod->name, symname);
	return 0;
999 1000 1001 1002 1003

bad_version:
	printk("%s: disagrees about version of symbol %s\n",
	       mod->name, symname);
	return 0;
L
Linus Torvalds 已提交
1004 1005 1006 1007 1008 1009 1010 1011
}

static inline int check_modstruct_version(Elf_Shdr *sechdrs,
					  unsigned int versindex,
					  struct module *mod)
{
	const unsigned long *crc;

1012 1013
	/* Since this should be found in kernel (which can't be removed),
	 * no locking is necessary. */
1014 1015
	if (!find_symbol(MODULE_SYMBOL_PREFIX "module_layout", NULL,
			 &crc, true, false))
L
Linus Torvalds 已提交
1016
		BUG();
1017 1018
	return check_version(sechdrs, versindex, "module_layout", mod, crc,
			     NULL);
L
Linus Torvalds 已提交
1019 1020
}

1021 1022 1023
/* 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)
L
Linus Torvalds 已提交
1024
{
1025 1026 1027 1028
	if (has_crcs) {
		amagic += strcspn(amagic, " ");
		bmagic += strcspn(bmagic, " ");
	}
L
Linus Torvalds 已提交
1029 1030 1031 1032 1033 1034 1035
	return strcmp(amagic, bmagic) == 0;
}
#else
static inline int check_version(Elf_Shdr *sechdrs,
				unsigned int versindex,
				const char *symname,
				struct module *mod, 
1036 1037
				const unsigned long *crc,
				const struct module *crc_owner)
L
Linus Torvalds 已提交
1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048
{
	return 1;
}

static inline int check_modstruct_version(Elf_Shdr *sechdrs,
					  unsigned int versindex,
					  struct module *mod)
{
	return 1;
}

1049 1050
static inline int same_magic(const char *amagic, const char *bmagic,
			     bool has_crcs)
L
Linus Torvalds 已提交
1051 1052 1053 1054 1055
{
	return strcmp(amagic, bmagic) == 0;
}
#endif /* CONFIG_MODVERSIONS */

1056
/* Resolve a symbol for this module.  I.e. if we find one, record usage. */
1057 1058 1059
static const struct kernel_symbol *resolve_symbol(Elf_Shdr *sechdrs,
						  unsigned int versindex,
						  const char *name,
1060 1061
						  struct module *mod,
						  char ownername[])
L
Linus Torvalds 已提交
1062 1063
{
	struct module *owner;
1064
	const struct kernel_symbol *sym;
L
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1065
	const unsigned long *crc;
1066
	int err;
L
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1067

1068
	mutex_lock(&module_mutex);
1069
	sym = find_symbol(name, &owner, &crc,
A
Andi Kleen 已提交
1070
			  !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
1071 1072 1073 1074 1075 1076
	if (!sym)
		goto unlock;

	if (!check_version(sechdrs, versindex, name, mod, crc, owner)) {
		sym = ERR_PTR(-EINVAL);
		goto getname;
L
Linus Torvalds 已提交
1077
	}
1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088

	err = ref_module(mod, owner);
	if (err) {
		sym = ERR_PTR(err);
		goto getname;
	}

getname:
	/* We must make copy under the lock if we failed to get ref. */
	strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
unlock:
1089
	mutex_unlock(&module_mutex);
1090
	return sym;
L
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1091 1092
}

1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111
static const struct kernel_symbol *resolve_symbol_wait(Elf_Shdr *sechdrs,
						       unsigned int versindex,
						       const char *name,
						       struct module *mod)
{
	const struct kernel_symbol *ksym;
	char ownername[MODULE_NAME_LEN];

	if (wait_event_interruptible_timeout(module_wq,
			!IS_ERR(ksym = resolve_symbol(sechdrs, versindex, name,
						      mod, ownername)) ||
			PTR_ERR(ksym) != -EBUSY,
					     30 * HZ) <= 0) {
		printk(KERN_WARNING "%s: gave up waiting for init of module %s.\n",
		       mod->name, ownername);
	}
	return ksym;
}

L
Linus Torvalds 已提交
1112 1113 1114 1115
/*
 * /sys/module/foo/sections stuff
 * J. Corbet <corbet@lwn.net>
 */
1116
#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
1117 1118 1119 1120 1121 1122

static inline bool sect_empty(const Elf_Shdr *sect)
{
	return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
}

1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136
struct module_sect_attr
{
	struct module_attribute mattr;
	char *name;
	unsigned long address;
};

struct module_sect_attrs
{
	struct attribute_group grp;
	unsigned int nsections;
	struct module_sect_attr attrs[0];
};

L
Linus Torvalds 已提交
1137 1138 1139 1140 1141 1142 1143 1144
static ssize_t module_sect_show(struct module_attribute *mattr,
				struct module *mod, char *buf)
{
	struct module_sect_attr *sattr =
		container_of(mattr, struct module_sect_attr, mattr);
	return sprintf(buf, "0x%lx\n", sattr->address);
}

1145 1146
static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
{
1147
	unsigned int section;
1148 1149 1150 1151 1152 1153

	for (section = 0; section < sect_attrs->nsections; section++)
		kfree(sect_attrs->attrs[section].name);
	kfree(sect_attrs);
}

L
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1154 1155 1156 1157 1158 1159 1160
static void add_sect_attrs(struct module *mod, unsigned int nsect,
		char *secstrings, Elf_Shdr *sechdrs)
{
	unsigned int nloaded = 0, i, size[2];
	struct module_sect_attrs *sect_attrs;
	struct module_sect_attr *sattr;
	struct attribute **gattr;
D
Daniel Walker 已提交
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L
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1162 1163
	/* Count loaded sections and allocate structures */
	for (i = 0; i < nsect; i++)
1164
		if (!sect_empty(&sechdrs[i]))
L
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1165 1166 1167 1168 1169
			nloaded++;
	size[0] = ALIGN(sizeof(*sect_attrs)
			+ nloaded * sizeof(sect_attrs->attrs[0]),
			sizeof(sect_attrs->grp.attrs[0]));
	size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
1170 1171
	sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
	if (sect_attrs == NULL)
L
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1172 1173 1174 1175 1176 1177
		return;

	/* Setup section attributes. */
	sect_attrs->grp.name = "sections";
	sect_attrs->grp.attrs = (void *)sect_attrs + size[0];

1178
	sect_attrs->nsections = 0;
L
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1179 1180 1181
	sattr = &sect_attrs->attrs[0];
	gattr = &sect_attrs->grp.attrs[0];
	for (i = 0; i < nsect; i++) {
1182
		if (sect_empty(&sechdrs[i]))
1183
			continue;
L
Linus Torvalds 已提交
1184
		sattr->address = sechdrs[i].sh_addr;
1185 1186 1187 1188 1189
		sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
					GFP_KERNEL);
		if (sattr->name == NULL)
			goto out;
		sect_attrs->nsections++;
1190
		sysfs_attr_init(&sattr->mattr.attr);
L
Linus Torvalds 已提交
1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204
		sattr->mattr.show = module_sect_show;
		sattr->mattr.store = NULL;
		sattr->mattr.attr.name = sattr->name;
		sattr->mattr.attr.mode = S_IRUGO;
		*(gattr++) = &(sattr++)->mattr.attr;
	}
	*gattr = NULL;

	if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
		goto out;

	mod->sect_attrs = sect_attrs;
	return;
  out:
1205
	free_sect_attrs(sect_attrs);
L
Linus Torvalds 已提交
1206 1207 1208 1209 1210 1211 1212 1213 1214
}

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. */
1215
		free_sect_attrs(mod->sect_attrs);
L
Linus Torvalds 已提交
1216 1217 1218 1219
		mod->sect_attrs = NULL;
	}
}

R
Roland McGrath 已提交
1220 1221 1222 1223 1224 1225 1226 1227 1228 1229
/*
 * /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[0];
};

1230
static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
R
Roland McGrath 已提交
1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247
				 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]);
1248
		kobject_put(notes_attrs->dir);
R
Roland McGrath 已提交
1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259
	}
	kfree(notes_attrs);
}

static void add_notes_attrs(struct module *mod, unsigned int nsect,
			    char *secstrings, Elf_Shdr *sechdrs)
{
	unsigned int notes, loaded, i;
	struct module_notes_attrs *notes_attrs;
	struct bin_attribute *nattr;

1260 1261 1262 1263
	/* failed to create section attributes, so can't create notes */
	if (!mod->sect_attrs)
		return;

R
Roland McGrath 已提交
1264 1265 1266
	/* Count notes sections and allocate structures.  */
	notes = 0;
	for (i = 0; i < nsect; i++)
1267
		if (!sect_empty(&sechdrs[i]) &&
R
Roland McGrath 已提交
1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282
		    (sechdrs[i].sh_type == SHT_NOTE))
			++notes;

	if (notes == 0)
		return;

	notes_attrs = kzalloc(sizeof(*notes_attrs)
			      + notes * sizeof(notes_attrs->attrs[0]),
			      GFP_KERNEL);
	if (notes_attrs == NULL)
		return;

	notes_attrs->notes = notes;
	nattr = &notes_attrs->attrs[0];
	for (loaded = i = 0; i < nsect; ++i) {
1283
		if (sect_empty(&sechdrs[i]))
R
Roland McGrath 已提交
1284 1285
			continue;
		if (sechdrs[i].sh_type == SHT_NOTE) {
1286
			sysfs_bin_attr_init(nattr);
R
Roland McGrath 已提交
1287 1288 1289 1290 1291 1292 1293 1294 1295 1296
			nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
			nattr->attr.mode = S_IRUGO;
			nattr->size = sechdrs[i].sh_size;
			nattr->private = (void *) sechdrs[i].sh_addr;
			nattr->read = module_notes_read;
			++nattr;
		}
		++loaded;
	}

1297
	notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
R
Roland McGrath 已提交
1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318
	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);
}

L
Linus Torvalds 已提交
1319
#else
1320

L
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1321 1322 1323 1324 1325 1326 1327 1328
static inline void add_sect_attrs(struct module *mod, unsigned int nsect,
		char *sectstrings, Elf_Shdr *sechdrs)
{
}

static inline void remove_sect_attrs(struct module *mod)
{
}
R
Roland McGrath 已提交
1329 1330 1331 1332 1333 1334 1335 1336 1337

static inline void add_notes_attrs(struct module *mod, unsigned int nsect,
				   char *sectstrings, Elf_Shdr *sechdrs)
{
}

static inline void remove_notes_attrs(struct module *mod)
{
}
1338
#endif
L
Linus Torvalds 已提交
1339

1340
#ifdef CONFIG_SYSFS
1341 1342 1343 1344 1345 1346
static void add_usage_links(struct module *mod)
{
#ifdef CONFIG_MODULE_UNLOAD
	struct module_use *use;
	int nowarn;

1347
	mutex_lock(&module_mutex);
1348 1349 1350 1351
	list_for_each_entry(use, &mod->target_list, target_list) {
		nowarn = sysfs_create_link(use->target->holders_dir,
					   &mod->mkobj.kobj, mod->name);
	}
1352
	mutex_unlock(&module_mutex);
1353 1354 1355 1356 1357 1358 1359 1360
#endif
}

static void del_usage_links(struct module *mod)
{
#ifdef CONFIG_MODULE_UNLOAD
	struct module_use *use;

1361
	mutex_lock(&module_mutex);
1362 1363
	list_for_each_entry(use, &mod->target_list, target_list)
		sysfs_remove_link(use->target->holders_dir, mod->name);
1364
	mutex_unlock(&module_mutex);
1365 1366 1367
#endif
}

1368
static int module_add_modinfo_attrs(struct module *mod)
1369 1370
{
	struct module_attribute *attr;
1371
	struct module_attribute *temp_attr;
1372 1373 1374
	int error = 0;
	int i;

1375 1376 1377 1378 1379 1380 1381
	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;
1382 1383
	for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
		if (!attr->test ||
1384 1385
		    (attr->test && attr->test(mod))) {
			memcpy(temp_attr, attr, sizeof(*temp_attr));
1386
			sysfs_attr_init(&temp_attr->attr);
1387 1388 1389
			error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
			++temp_attr;
		}
1390 1391 1392 1393
	}
	return error;
}

1394
static void module_remove_modinfo_attrs(struct module *mod)
1395 1396 1397 1398
{
	struct module_attribute *attr;
	int i;

1399 1400 1401 1402
	for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
		/* pick a field to test for end of list */
		if (!attr->attr.name)
			break;
1403
		sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1404 1405
		if (attr->free)
			attr->free(mod);
1406
	}
1407
	kfree(mod->modinfo_attrs);
1408
}
L
Linus Torvalds 已提交
1409

1410
static int mod_sysfs_init(struct module *mod)
L
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1411 1412
{
	int err;
1413
	struct kobject *kobj;
L
Linus Torvalds 已提交
1414

1415 1416
	if (!module_sysfs_initialized) {
		printk(KERN_ERR "%s: module sysfs not initialized\n",
1417 1418 1419 1420
		       mod->name);
		err = -EINVAL;
		goto out;
	}
1421 1422 1423 1424 1425 1426 1427 1428 1429

	kobj = kset_find_obj(module_kset, mod->name);
	if (kobj) {
		printk(KERN_ERR "%s: module is already loaded\n", mod->name);
		kobject_put(kobj);
		err = -EINVAL;
		goto out;
	}

L
Linus Torvalds 已提交
1430
	mod->mkobj.mod = mod;
1431

1432 1433 1434 1435 1436 1437
	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)
		kobject_put(&mod->mkobj.kobj);
K
Kay Sievers 已提交
1438

1439
	/* delay uevent until full sysfs population */
K
Kay Sievers 已提交
1440 1441 1442 1443
out:
	return err;
}

1444
static int mod_sysfs_setup(struct module *mod,
K
Kay Sievers 已提交
1445 1446 1447 1448 1449
			   struct kernel_param *kparam,
			   unsigned int num_params)
{
	int err;

1450 1451 1452 1453
	err = mod_sysfs_init(mod);
	if (err)
		goto out;

1454
	mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
1455 1456
	if (!mod->holders_dir) {
		err = -ENOMEM;
K
Kay Sievers 已提交
1457
		goto out_unreg;
1458
	}
K
Kay Sievers 已提交
1459

L
Linus Torvalds 已提交
1460 1461
	err = module_param_sysfs_setup(mod, kparam, num_params);
	if (err)
K
Kay Sievers 已提交
1462
		goto out_unreg_holders;
L
Linus Torvalds 已提交
1463

1464 1465
	err = module_add_modinfo_attrs(mod);
	if (err)
1466
		goto out_unreg_param;
1467

1468 1469
	add_usage_links(mod);

1470
	kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
L
Linus Torvalds 已提交
1471 1472
	return 0;

1473 1474
out_unreg_param:
	module_param_sysfs_remove(mod);
K
Kay Sievers 已提交
1475
out_unreg_holders:
1476
	kobject_put(mod->holders_dir);
K
Kay Sievers 已提交
1477
out_unreg:
1478
	kobject_put(&mod->mkobj.kobj);
1479
out:
L
Linus Torvalds 已提交
1480 1481
	return err;
}
1482 1483 1484 1485 1486 1487 1488 1489

static void mod_sysfs_fini(struct module *mod)
{
	kobject_put(&mod->mkobj.kobj);
}

#else /* CONFIG_SYSFS */

1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510
static inline int mod_sysfs_init(struct module *mod)
{
	return 0;
}

static inline int mod_sysfs_setup(struct module *mod,
			   struct kernel_param *kparam,
			   unsigned int num_params)
{
	return 0;
}

static inline int module_add_modinfo_attrs(struct module *mod)
{
	return 0;
}

static inline void module_remove_modinfo_attrs(struct module *mod)
{
}

1511 1512 1513 1514
static void mod_sysfs_fini(struct module *mod)
{
}

1515 1516 1517 1518
static void del_usage_links(struct module *mod)
{
}

1519
#endif /* CONFIG_SYSFS */
L
Linus Torvalds 已提交
1520 1521 1522

static void mod_kobject_remove(struct module *mod)
{
1523
	del_usage_links(mod);
1524
	module_remove_modinfo_attrs(mod);
L
Linus Torvalds 已提交
1525
	module_param_sysfs_remove(mod);
1526 1527
	kobject_put(mod->mkobj.drivers_dir);
	kobject_put(mod->holders_dir);
1528
	mod_sysfs_fini(mod);
L
Linus Torvalds 已提交
1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541
}

/*
 * unlink the module with the whole machine is stopped with interrupts off
 * - this defends against kallsyms not taking locks
 */
static int __unlink_module(void *_mod)
{
	struct module *mod = _mod;
	list_del(&mod->list);
	return 0;
}

1542
/* Free a module, remove from lists, etc. */
L
Linus Torvalds 已提交
1543 1544
static void free_module(struct module *mod)
{
1545 1546
	trace_module_free(mod);

L
Linus Torvalds 已提交
1547
	/* Delete from various lists */
1548
	mutex_lock(&module_mutex);
1549
	stop_machine(__unlink_module, mod, NULL);
1550
	mutex_unlock(&module_mutex);
R
Roland McGrath 已提交
1551
	remove_notes_attrs(mod);
L
Linus Torvalds 已提交
1552 1553 1554
	remove_sect_attrs(mod);
	mod_kobject_remove(mod);

1555 1556 1557
	/* Remove dynamic debug info */
	ddebug_remove_module(mod->name);

L
Linus Torvalds 已提交
1558 1559 1560 1561 1562 1563
	/* Arch-specific cleanup. */
	module_arch_cleanup(mod);

	/* Module unload stuff */
	module_unload_free(mod);

1564 1565 1566
	/* Free any allocated parameters. */
	destroy_params(mod->kp, mod->num_kp);

L
Linus Torvalds 已提交
1567 1568 1569
	/* This may be NULL, but that's OK */
	module_free(mod, mod->module_init);
	kfree(mod->args);
1570
	percpu_modfree(mod);
1571

I
Ingo Molnar 已提交
1572 1573 1574
	/* Free lock-classes: */
	lockdep_free_key_range(mod->module_core, mod->core_size);

L
Linus Torvalds 已提交
1575 1576
	/* Finally, free the core (containing the module structure) */
	module_free(mod, mod->module_core);
1577 1578 1579 1580

#ifdef CONFIG_MPU
	update_protections(current->mm);
#endif
L
Linus Torvalds 已提交
1581 1582 1583 1584 1585
}

void *__symbol_get(const char *symbol)
{
	struct module *owner;
1586
	const struct kernel_symbol *sym;
L
Linus Torvalds 已提交
1587

R
Rusty Russell 已提交
1588
	preempt_disable();
1589 1590 1591
	sym = find_symbol(symbol, &owner, NULL, true, true);
	if (sym && strong_try_module_get(owner))
		sym = NULL;
R
Rusty Russell 已提交
1592
	preempt_enable();
L
Linus Torvalds 已提交
1593

1594
	return sym ? (void *)sym->value : NULL;
L
Linus Torvalds 已提交
1595 1596 1597
}
EXPORT_SYMBOL_GPL(__symbol_get);

1598 1599
/*
 * Ensure that an exported symbol [global namespace] does not already exist
1600
 * in the kernel or in some other module's exported symbol table.
1601 1602
 *
 * You must hold the module_mutex.
1603 1604 1605
 */
static int verify_export_symbols(struct module *mod)
{
1606
	unsigned int i;
1607
	struct module *owner;
1608 1609 1610 1611 1612 1613 1614 1615
	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 },
		{ mod->gpl_future_syms, mod->num_gpl_future_syms },
1616
#ifdef CONFIG_UNUSED_SYMBOLS
1617 1618
		{ mod->unused_syms, mod->num_unused_syms },
		{ mod->unused_gpl_syms, mod->num_unused_gpl_syms },
1619
#endif
1620
	};
1621

1622 1623
	for (i = 0; i < ARRAY_SIZE(arr); i++) {
		for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
1624
			if (find_symbol(s->name, &owner, NULL, true, false)) {
1625 1626 1627 1628 1629 1630
				printk(KERN_ERR
				       "%s: exports duplicate symbol %s"
				       " (owned by %s)\n",
				       mod->name, s->name, module_name(owner));
				return -ENOEXEC;
			}
1631
		}
1632 1633
	}
	return 0;
1634 1635
}

1636
/* Change all symbols so that st_value encodes the pointer directly. */
L
Linus Torvalds 已提交
1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647
static int simplify_symbols(Elf_Shdr *sechdrs,
			    unsigned int symindex,
			    const char *strtab,
			    unsigned int versindex,
			    unsigned int pcpuindex,
			    struct module *mod)
{
	Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
	unsigned long secbase;
	unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
	int ret = 0;
1648
	const struct kernel_symbol *ksym;
L
Linus Torvalds 已提交
1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667

	for (i = 1; i < n; i++) {
		switch (sym[i].st_shndx) {
		case SHN_COMMON:
			/* We compiled with -fno-common.  These are not
			   supposed to happen.  */
			DEBUGP("Common symbol: %s\n", strtab + sym[i].st_name);
			printk("%s: please compile with -fno-common\n",
			       mod->name);
			ret = -ENOEXEC;
			break;

		case SHN_ABS:
			/* Don't need to do anything */
			DEBUGP("Absolute symbol: 0x%08lx\n",
			       (long)sym[i].st_value);
			break;

		case SHN_UNDEF:
1668 1669 1670
			ksym = resolve_symbol_wait(sechdrs, versindex,
						   strtab + sym[i].st_name,
						   mod);
L
Linus Torvalds 已提交
1671
			/* Ok if resolved.  */
1672
			if (ksym && !IS_ERR(ksym)) {
1673
				sym[i].st_value = ksym->value;
L
Linus Torvalds 已提交
1674
				break;
1675 1676
			}

L
Linus Torvalds 已提交
1677
			/* Ok if weak.  */
1678
			if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
L
Linus Torvalds 已提交
1679 1680
				break;

1681 1682 1683 1684
			printk(KERN_WARNING "%s: Unknown symbol %s (err %li)\n",
			       mod->name, strtab + sym[i].st_name,
			       PTR_ERR(ksym));
			ret = PTR_ERR(ksym) ?: -ENOENT;
L
Linus Torvalds 已提交
1685 1686 1687 1688 1689
			break;

		default:
			/* Divert to percpu allocation if a percpu var. */
			if (sym[i].st_shndx == pcpuindex)
1690
				secbase = (unsigned long)mod_percpu(mod);
L
Linus Torvalds 已提交
1691 1692 1693 1694 1695 1696 1697 1698 1699 1700
			else
				secbase = sechdrs[sym[i].st_shndx].sh_addr;
			sym[i].st_value += secbase;
			break;
		}
	}

	return ret;
}

1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733
static int apply_relocations(struct module *mod,
			     Elf_Ehdr *hdr,
			     Elf_Shdr *sechdrs,
			     unsigned int symindex,
			     unsigned int strindex)
{
	unsigned int i;
	int err = 0;

	/* Now do relocations. */
	for (i = 1; i < hdr->e_shnum; i++) {
		const char *strtab = (char *)sechdrs[strindex].sh_addr;
		unsigned int info = sechdrs[i].sh_info;

		/* Not a valid relocation section? */
		if (info >= hdr->e_shnum)
			continue;

		/* Don't bother with non-allocated sections */
		if (!(sechdrs[info].sh_flags & SHF_ALLOC))
			continue;

		if (sechdrs[i].sh_type == SHT_REL)
			err = apply_relocate(sechdrs, strtab, symindex, i, mod);
		else if (sechdrs[i].sh_type == SHT_RELA)
			err = apply_relocate_add(sechdrs, strtab, symindex, i,
						 mod);
		if (err < 0)
			break;
	}
	return err;
}

1734 1735 1736 1737 1738 1739 1740 1741
/* 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;
}

L
Linus Torvalds 已提交
1742
/* Update size with this section: return offset. */
1743 1744
static long get_offset(struct module *mod, unsigned int *size,
		       Elf_Shdr *sechdr, unsigned int section)
L
Linus Torvalds 已提交
1745 1746 1747
{
	long ret;

1748
	*size += arch_mod_section_prepend(mod, section);
L
Linus Torvalds 已提交
1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784
	ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
	*size = ret + sechdr->sh_size;
	return ret;
}

/* 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,
			    const Elf_Ehdr *hdr,
			    Elf_Shdr *sechdrs,
			    const char *secstrings)
{
	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_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
		{ ARCH_SHF_SMALL | SHF_ALLOC, 0 }
	};
	unsigned int m, i;

	for (i = 0; i < hdr->e_shnum; i++)
		sechdrs[i].sh_entsize = ~0UL;

	DEBUGP("Core section allocation order:\n");
	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
		for (i = 0; i < hdr->e_shnum; ++i) {
			Elf_Shdr *s = &sechdrs[i];

			if ((s->sh_flags & masks[m][0]) != masks[m][0]
			    || (s->sh_flags & masks[m][1])
			    || s->sh_entsize != ~0UL
R
Rusty Russell 已提交
1785
			    || strstarts(secstrings + s->sh_name, ".init"))
L
Linus Torvalds 已提交
1786
				continue;
1787
			s->sh_entsize = get_offset(mod, &mod->core_size, s, i);
L
Linus Torvalds 已提交
1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801
			DEBUGP("\t%s\n", secstrings + s->sh_name);
		}
		if (m == 0)
			mod->core_text_size = mod->core_size;
	}

	DEBUGP("Init section allocation order:\n");
	for (m = 0; m < ARRAY_SIZE(masks); ++m) {
		for (i = 0; i < hdr->e_shnum; ++i) {
			Elf_Shdr *s = &sechdrs[i];

			if ((s->sh_flags & masks[m][0]) != masks[m][0]
			    || (s->sh_flags & masks[m][1])
			    || s->sh_entsize != ~0UL
R
Rusty Russell 已提交
1802
			    || !strstarts(secstrings + s->sh_name, ".init"))
L
Linus Torvalds 已提交
1803
				continue;
1804
			s->sh_entsize = (get_offset(mod, &mod->init_size, s, i)
L
Linus Torvalds 已提交
1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817
					 | INIT_OFFSET_MASK);
			DEBUGP("\t%s\n", secstrings + s->sh_name);
		}
		if (m == 0)
			mod->init_text_size = mod->init_size;
	}
}

static void set_license(struct module *mod, const char *license)
{
	if (!license)
		license = "unspecified";

1818
	if (!license_is_gpl_compatible(license)) {
A
Andi Kleen 已提交
1819
		if (!test_taint(TAINT_PROPRIETARY_MODULE))
1820
			printk(KERN_WARNING "%s: module license '%s' taints "
1821 1822
				"kernel.\n", mod->name, license);
		add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
L
Linus Torvalds 已提交
1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844
	}
}

/* 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;
}

1845
static char *get_modinfo(const Elf_Shdr *sechdrs,
L
Linus Torvalds 已提交
1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859
			 unsigned int info,
			 const char *tag)
{
	char *p;
	unsigned int taglen = strlen(tag);
	unsigned long size = sechdrs[info].sh_size;

	for (p = (char *)sechdrs[info].sh_addr; p; p = next_string(p, &size)) {
		if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
			return p + taglen + 1;
	}
	return NULL;
}

1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874
static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs,
			  unsigned int infoindex)
{
	struct module_attribute *attr;
	int i;

	for (i = 0; (attr = modinfo_attrs[i]); i++) {
		if (attr->setup)
			attr->setup(mod,
				    get_modinfo(sechdrs,
						infoindex,
						attr->attr.name));
	}
}

1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885
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);
	}
}

L
Linus Torvalds 已提交
1886
#ifdef CONFIG_KALLSYMS
1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899

/* lookup symbol in given range of kernel_symbols */
static const struct kernel_symbol *lookup_symbol(const char *name,
	const struct kernel_symbol *start,
	const struct kernel_symbol *stop)
{
	const struct kernel_symbol *ks = start;
	for (; ks < stop; ks++)
		if (strcmp(ks->name, name) == 0)
			return ks;
	return NULL;
}

1900 1901
static int is_exported(const char *name, unsigned long value,
		       const struct module *mod)
L
Linus Torvalds 已提交
1902
{
1903 1904 1905
	const struct kernel_symbol *ks;
	if (!mod)
		ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
1906
	else
1907 1908
		ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
	return ks != NULL && ks->value == value;
L
Linus Torvalds 已提交
1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945
}

/* As per nm */
static char elf_type(const Elf_Sym *sym,
		     Elf_Shdr *sechdrs,
		     const char *secstrings,
		     struct module *mod)
{
	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)
		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';
	}
R
Rusty Russell 已提交
1946
	if (strstarts(secstrings + sechdrs[sym->st_shndx].sh_name, ".debug"))
L
Linus Torvalds 已提交
1947 1948 1949 1950
		return 'n';
	return '?';
}

1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974
static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
                           unsigned int shnum)
{
	const Elf_Shdr *sec;

	if (src->st_shndx == SHN_UNDEF
	    || src->st_shndx >= shnum
	    || !src->st_name)
		return false;

	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;
}

static unsigned long layout_symtab(struct module *mod,
				   Elf_Shdr *sechdrs,
				   unsigned int symindex,
1975
				   unsigned int strindex,
1976
				   const Elf_Ehdr *hdr,
1977 1978 1979
				   const char *secstrings,
				   unsigned long *pstroffs,
				   unsigned long *strmap)
1980 1981 1982
{
	unsigned long symoffs;
	Elf_Shdr *symsect = sechdrs + symindex;
1983
	Elf_Shdr *strsect = sechdrs + strindex;
1984
	const Elf_Sym *src;
1985
	const char *strtab;
1986 1987 1988 1989 1990 1991 1992 1993 1994 1995
	unsigned int i, nsrc, ndst;

	/* Put symbol section at end of init part of module. */
	symsect->sh_flags |= SHF_ALLOC;
	symsect->sh_entsize = get_offset(mod, &mod->init_size, symsect,
					 symindex) | INIT_OFFSET_MASK;
	DEBUGP("\t%s\n", secstrings + symsect->sh_name);

	src = (void *)hdr + symsect->sh_offset;
	nsrc = symsect->sh_size / sizeof(*src);
1996
	strtab = (void *)hdr + strsect->sh_offset;
1997
	for (ndst = i = 1; i < nsrc; ++i, ++src)
1998 1999 2000 2001 2002
		if (is_core_symbol(src, sechdrs, hdr->e_shnum)) {
			unsigned int j = src->st_name;

			while(!__test_and_set_bit(j, strmap) && strtab[j])
				++j;
2003
			++ndst;
2004
		}
2005 2006 2007 2008 2009

	/* Append room for core symbols at end of core part. */
	symoffs = ALIGN(mod->core_size, symsect->sh_addralign ?: 1);
	mod->core_size = symoffs + ndst * sizeof(Elf_Sym);

2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
	/* Put string table section at end of init part of module. */
	strsect->sh_flags |= SHF_ALLOC;
	strsect->sh_entsize = get_offset(mod, &mod->init_size, strsect,
					 strindex) | INIT_OFFSET_MASK;
	DEBUGP("\t%s\n", secstrings + strsect->sh_name);

	/* Append room for core symbols' strings at end of core part. */
	*pstroffs = mod->core_size;
	__set_bit(0, strmap);
	mod->core_size += bitmap_weight(strmap, strsect->sh_size);

2021 2022 2023
	return symoffs;
}

L
Linus Torvalds 已提交
2024 2025
static void add_kallsyms(struct module *mod,
			 Elf_Shdr *sechdrs,
2026
			 unsigned int shnum,
L
Linus Torvalds 已提交
2027 2028
			 unsigned int symindex,
			 unsigned int strindex,
2029
			 unsigned long symoffs,
2030 2031 2032
			 unsigned long stroffs,
			 const char *secstrings,
			 unsigned long *strmap)
L
Linus Torvalds 已提交
2033
{
2034 2035 2036
	unsigned int i, ndst;
	const Elf_Sym *src;
	Elf_Sym *dst;
2037
	char *s;
L
Linus Torvalds 已提交
2038 2039 2040 2041 2042 2043 2044 2045 2046

	mod->symtab = (void *)sechdrs[symindex].sh_addr;
	mod->num_symtab = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
	mod->strtab = (void *)sechdrs[strindex].sh_addr;

	/* Set types up while we still have access to sections. */
	for (i = 0; i < mod->num_symtab; i++)
		mod->symtab[i].st_info
			= elf_type(&mod->symtab[i], sechdrs, secstrings, mod);
2047 2048 2049 2050 2051 2052 2053 2054

	mod->core_symtab = dst = mod->module_core + symoffs;
	src = mod->symtab;
	*dst = *src;
	for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
		if (!is_core_symbol(src, sechdrs, shnum))
			continue;
		dst[ndst] = *src;
2055
		dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
2056 2057 2058
		++ndst;
	}
	mod->core_num_syms = ndst;
2059 2060 2061 2062 2063

	mod->core_strtab = s = mod->module_core + stroffs;
	for (*s = 0, i = 1; i < sechdrs[strindex].sh_size; ++i)
		if (test_bit(i, strmap))
			*++s = mod->strtab[i];
L
Linus Torvalds 已提交
2064 2065
}
#else
2066 2067 2068
static inline unsigned long layout_symtab(struct module *mod,
					  Elf_Shdr *sechdrs,
					  unsigned int symindex,
2069
					  unsigned int strindex,
2070
					  const Elf_Ehdr *hdr,
2071 2072 2073
					  const char *secstrings,
					  unsigned long *pstroffs,
					  unsigned long *strmap)
2074
{
2075
	return 0;
2076
}
2077

L
Linus Torvalds 已提交
2078 2079
static inline void add_kallsyms(struct module *mod,
				Elf_Shdr *sechdrs,
2080
				unsigned int shnum,
L
Linus Torvalds 已提交
2081 2082
				unsigned int symindex,
				unsigned int strindex,
2083
				unsigned long symoffs,
2084 2085 2086
				unsigned long stroffs,
				const char *secstrings,
				const unsigned long *strmap)
L
Linus Torvalds 已提交
2087 2088 2089 2090
{
}
#endif /* CONFIG_KALLSYMS */

2091
static void dynamic_debug_setup(struct _ddebug *debug, unsigned int num)
2092
{
2093 2094 2095 2096 2097
#ifdef CONFIG_DYNAMIC_DEBUG
	if (ddebug_add_module(debug, num, debug->modname))
		printk(KERN_ERR "dynamic debug error adding module: %s\n",
					debug->modname);
#endif
R
Rusty Russell 已提交
2098
}
2099

2100 2101 2102 2103 2104 2105
static void dynamic_debug_remove(struct _ddebug *debug)
{
	if (debug)
		ddebug_remove_module(debug->modname);
}

2106 2107 2108 2109 2110
static void *module_alloc_update_bounds(unsigned long size)
{
	void *ret = module_alloc(size);

	if (ret) {
2111
		mutex_lock(&module_mutex);
2112 2113 2114 2115 2116
		/* Update module bounds. */
		if ((unsigned long)ret < module_addr_min)
			module_addr_min = (unsigned long)ret;
		if ((unsigned long)ret + size > module_addr_max)
			module_addr_max = (unsigned long)ret + size;
2117
		mutex_unlock(&module_mutex);
2118 2119 2120 2121
	}
	return ret;
}

C
Catalin Marinas 已提交
2122 2123
#ifdef CONFIG_DEBUG_KMEMLEAK
static void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2124 2125
				 const Elf_Shdr *sechdrs,
				 const char *secstrings)
C
Catalin Marinas 已提交
2126 2127 2128 2129
{
	unsigned int i;

	/* only scan the sections containing data */
2130
	kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
C
Catalin Marinas 已提交
2131 2132 2133 2134 2135 2136 2137 2138

	for (i = 1; i < hdr->e_shnum; i++) {
		if (!(sechdrs[i].sh_flags & SHF_ALLOC))
			continue;
		if (strncmp(secstrings + sechdrs[i].sh_name, ".data", 5) != 0
		    && strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) != 0)
			continue;

2139
		kmemleak_scan_area((void *)sechdrs[i].sh_addr,
C
Catalin Marinas 已提交
2140 2141 2142 2143 2144
				   sechdrs[i].sh_size, GFP_KERNEL);
	}
}
#else
static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
2145 2146
					Elf_Shdr *sechdrs,
					const char *secstrings)
C
Catalin Marinas 已提交
2147 2148 2149 2150
{
}
#endif

L
Linus Torvalds 已提交
2151 2152 2153 2154 2155 2156 2157 2158 2159 2160
struct load_info {
	Elf_Ehdr *hdr;
	unsigned long len;
	Elf_Shdr *sechdrs;
	char *secstrings, *args, *strtab;
	struct {
		unsigned int sym, str, mod, vers, info, pcpu;
	} index;
};

2161
/* Sets info->hdr and info->len. */
L
Linus Torvalds 已提交
2162
static int copy_and_check(struct load_info *info, const void __user *umod, unsigned long len)
2163 2164 2165 2166 2167 2168 2169 2170 2171
{
	int err;
	Elf_Ehdr *hdr;

	if (len < sizeof(*hdr))
		return -ENOEXEC;

	/* Suck in entire file: we'll want most of it. */
	/* vmalloc barfs on "unusual" numbers.  Check here */
L
Linus Torvalds 已提交
2172
	if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193
		return -ENOMEM;

	if (copy_from_user(hdr, umod, len) != 0) {
		err = -EFAULT;
		goto free_hdr;
	}

	/* Sanity checks against insmoding binaries or wrong arch,
	   weird elf version */
	if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
	    || hdr->e_type != ET_REL
	    || !elf_check_arch(hdr)
	    || hdr->e_shentsize != sizeof(Elf_Shdr)) {
		err = -ENOEXEC;
		goto free_hdr;
	}

	if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
		err = -ENOEXEC;
		goto free_hdr;
	}
L
Linus Torvalds 已提交
2194 2195
	info->hdr = hdr;
	info->len = len;
2196 2197 2198 2199 2200 2201 2202
	return 0;

free_hdr:
	vfree(hdr);
	return err;
}

2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235
static int rewrite_section_headers(struct load_info *info)
{
	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];
		if (shdr->sh_type != SHT_NOBITS
		    && info->len < shdr->sh_offset + shdr->sh_size) {
			printk(KERN_ERR "Module len %lu truncated\n",
			       info->len);
			return -ENOEXEC;
		}

		/* Mark all sections sh_addr with their address in the
		   temporary image. */
		shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;

#ifndef CONFIG_MODULE_UNLOAD
		/* Don't load .exit sections */
		if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
			shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
#endif
		/* Don't keep modinfo and version sections. */
		if (!strcmp(info->secstrings+shdr->sh_name, "__versions")
		    || !strcmp(info->secstrings+shdr->sh_name, ".modinfo"))
			shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
	}
	return 0;
}

L
Linus Torvalds 已提交
2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246
/*
 * Set up our basic convenience variables (pointers to section headers,
 * search for module section index etc), and do some basic section
 * verification.
 *
 * Return the temporary module pointer (we'll replace it with the final
 * one when we move the module sections around).
 */
static struct module *setup_load_info(struct load_info *info)
{
	unsigned int i;
2247
	int err;
L
Linus Torvalds 已提交
2248 2249 2250 2251
	struct module *mod;

	/* Set up the convenience variables */
	info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
2252 2253
	info->secstrings = (void *)info->hdr
		+ info->sechdrs[info->hdr->e_shstrndx].sh_offset;
L
Linus Torvalds 已提交
2254

2255 2256 2257
	err = rewrite_section_headers(info);
	if (err)
		return ERR_PTR(err);
L
Linus Torvalds 已提交
2258

2259 2260
	/* Find internal symbols and strings. */
	for (i = 1; i < info->hdr->e_shnum; i++) {
L
Linus Torvalds 已提交
2261 2262 2263
		if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
			info->index.sym = i;
			info->index.str = info->sechdrs[i].sh_link;
2264 2265 2266
			info->strtab = (char *)info->hdr
				+ info->sechdrs[info->index.str].sh_offset;
			break;
L
Linus Torvalds 已提交
2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295
		}
	}

	info->index.mod = find_sec(info->hdr, info->sechdrs, info->secstrings,
			    ".gnu.linkonce.this_module");
	if (!info->index.mod) {
		printk(KERN_WARNING "No module found in object\n");
		return ERR_PTR(-ENOEXEC);
	}
	/* This is temporary: point mod into copy of data. */
	mod = (void *)info->sechdrs[info->index.mod].sh_addr;

	if (info->index.sym == 0) {
		printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
		       mod->name);
		return ERR_PTR(-ENOEXEC);
	}

	info->index.vers = find_sec(info->hdr, info->sechdrs, info->secstrings, "__versions");
	info->index.info = find_sec(info->hdr, info->sechdrs, info->secstrings, ".modinfo");
	info->index.pcpu = find_pcpusec(info->hdr, info->sechdrs, info->secstrings);

	/* Check module struct version now, before we try to use module. */
	if (!check_modstruct_version(info->sechdrs, info->index.vers, mod))
		return ERR_PTR(-ENOEXEC);

	return mod;
}

2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319
static int check_modinfo(struct module *mod,
			 const Elf_Shdr *sechdrs,
			 unsigned int infoindex, unsigned int versindex)
{
	const char *modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
	int err;

	/* 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, versindex)) {
		printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
		       mod->name, modmagic, vermagic);
		return -ENOEXEC;
	}

	if (get_modinfo(sechdrs, infoindex, "staging")) {
		add_taint_module(mod, TAINT_CRAP);
		printk(KERN_WARNING "%s: module is from the staging directory,"
		       " the quality is unknown, you have been warned.\n",
		       mod->name);
	}
2320 2321 2322 2323

	/* Set up license info based on the info section */
	set_license(mod, get_modinfo(sechdrs, infoindex, "license"));

2324 2325 2326
	return 0;
}

L
Linus Torvalds 已提交
2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389
static void find_module_sections(struct module *mod, Elf_Ehdr *hdr,
				 Elf_Shdr *sechdrs, const char *secstrings)
{
	mod->kp = section_objs(hdr, sechdrs, secstrings, "__param",
			       sizeof(*mod->kp), &mod->num_kp);
	mod->syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab",
				 sizeof(*mod->syms), &mod->num_syms);
	mod->crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab");
	mod->gpl_syms = section_objs(hdr, sechdrs, secstrings, "__ksymtab_gpl",
				     sizeof(*mod->gpl_syms),
				     &mod->num_gpl_syms);
	mod->gpl_crcs = section_addr(hdr, sechdrs, secstrings, "__kcrctab_gpl");
	mod->gpl_future_syms = section_objs(hdr, sechdrs, secstrings,
					    "__ksymtab_gpl_future",
					    sizeof(*mod->gpl_future_syms),
					    &mod->num_gpl_future_syms);
	mod->gpl_future_crcs = section_addr(hdr, sechdrs, secstrings,
					    "__kcrctab_gpl_future");

#ifdef CONFIG_UNUSED_SYMBOLS
	mod->unused_syms = section_objs(hdr, sechdrs, secstrings,
					"__ksymtab_unused",
					sizeof(*mod->unused_syms),
					&mod->num_unused_syms);
	mod->unused_crcs = section_addr(hdr, sechdrs, secstrings,
					"__kcrctab_unused");
	mod->unused_gpl_syms = section_objs(hdr, sechdrs, secstrings,
					    "__ksymtab_unused_gpl",
					    sizeof(*mod->unused_gpl_syms),
					    &mod->num_unused_gpl_syms);
	mod->unused_gpl_crcs = section_addr(hdr, sechdrs, secstrings,
					    "__kcrctab_unused_gpl");
#endif
#ifdef CONFIG_CONSTRUCTORS
	mod->ctors = section_objs(hdr, sechdrs, secstrings, ".ctors",
				  sizeof(*mod->ctors), &mod->num_ctors);
#endif

#ifdef CONFIG_TRACEPOINTS
	mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
					"__tracepoints",
					sizeof(*mod->tracepoints),
					&mod->num_tracepoints);
#endif
#ifdef CONFIG_EVENT_TRACING
	mod->trace_events = section_objs(hdr, sechdrs, secstrings,
					 "_ftrace_events",
					 sizeof(*mod->trace_events),
					 &mod->num_trace_events);
	/*
	 * This section contains pointers to allocated objects in the trace
	 * code and not scanning it leads to false positives.
	 */
	kmemleak_scan_area(mod->trace_events, sizeof(*mod->trace_events) *
			   mod->num_trace_events, GFP_KERNEL);
#endif
#ifdef CONFIG_FTRACE_MCOUNT_RECORD
	/* sechdrs[0].sh_size is always zero */
	mod->ftrace_callsites = section_objs(hdr, sechdrs, secstrings,
					     "__mcount_loc",
					     sizeof(*mod->ftrace_callsites),
					     &mod->num_ftrace_callsites);
#endif
2390 2391 2392 2393

	if (section_addr(hdr, sechdrs, secstrings, "__obsparm"))
		printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
		       mod->name);
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Linus Torvalds 已提交
2394 2395
}

2396 2397 2398 2399 2400 2401 2402 2403 2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422 2423 2424 2425 2426 2427 2428 2429 2430 2431 2432 2433 2434 2435 2436 2437 2438 2439 2440 2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459
static struct module *move_module(struct module *mod,
				  Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
				  const char *secstrings, unsigned modindex)
{
	int i;
	void *ptr;

	/* Do the allocs. */
	ptr = module_alloc_update_bounds(mod->core_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 ERR_PTR(-ENOMEM);

	memset(ptr, 0, mod->core_size);
	mod->module_core = ptr;

	ptr = module_alloc_update_bounds(mod->init_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 && mod->init_size) {
		module_free(mod, mod->module_core);
		return ERR_PTR(-ENOMEM);
	}
	memset(ptr, 0, mod->init_size);
	mod->module_init = ptr;

	/* Transfer each section which specifies SHF_ALLOC */
	DEBUGP("final section addresses:\n");
	for (i = 0; i < hdr->e_shnum; i++) {
		void *dest;

		if (!(sechdrs[i].sh_flags & SHF_ALLOC))
			continue;

		if (sechdrs[i].sh_entsize & INIT_OFFSET_MASK)
			dest = mod->module_init
				+ (sechdrs[i].sh_entsize & ~INIT_OFFSET_MASK);
		else
			dest = mod->module_core + sechdrs[i].sh_entsize;

		if (sechdrs[i].sh_type != SHT_NOBITS)
			memcpy(dest, (void *)sechdrs[i].sh_addr,
			       sechdrs[i].sh_size);
		/* Update sh_addr to point to copy in image. */
		sechdrs[i].sh_addr = (unsigned long)dest;
		DEBUGP("\t0x%lx %s\n",
		       sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
	}
	/* Module has been moved. */
	mod = (void *)sechdrs[modindex].sh_addr;
	kmemleak_load_module(mod, hdr, sechdrs, secstrings);
	return mod;
}

2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513
static int check_module_license_and_versions(struct module *mod,
					     Elf_Shdr *sechdrs)
{
	/*
	 * 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);

	/* driverloader was caught wrongly pretending to be under GPL */
	if (strcmp(mod->name, "driverloader") == 0)
		add_taint_module(mod, TAINT_PROPRIETARY_MODULE);

#ifdef CONFIG_MODVERSIONS
	if ((mod->num_syms && !mod->crcs)
	    || (mod->num_gpl_syms && !mod->gpl_crcs)
	    || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
#ifdef CONFIG_UNUSED_SYMBOLS
	    || (mod->num_unused_syms && !mod->unused_crcs)
	    || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
#endif
		) {
		return try_to_force_load(mod,
					 "no versions for exported symbols");
	}
#endif
	return 0;
}

static void flush_module_icache(const struct module *mod)
{
	mm_segment_t old_fs;

	/* flush the icache in correct context */
	old_fs = get_fs();
	set_fs(KERNEL_DS);

	/*
	 * 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->module_init)
		flush_icache_range((unsigned long)mod->module_init,
				   (unsigned long)mod->module_init
				   + mod->init_size);
	flush_icache_range((unsigned long)mod->module_core,
			   (unsigned long)mod->module_core + mod->core_size);

	set_fs(old_fs);
}

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2514 2515
/* Allocate and load the module: note that size of section 0 is always
   zero, and we rely on this for optional sections. */
2516
static noinline struct module *load_module(void __user *umod,
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2517 2518 2519
				  unsigned long len,
				  const char __user *uargs)
{
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2520
	struct load_info info = { NULL, };
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2521
	struct module *mod;
2522
	long err;
2523
	unsigned long symoffs, stroffs, *strmap;
2524
	void __percpu *percpu;
2525 2526
	struct _ddebug *debug = NULL;
	unsigned int num_debug = 0;
2527

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2528 2529 2530
	DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
	       umod, len, uargs);

L
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2531
	err = copy_and_check(&info, umod, len);
2532 2533
	if (err)
		return ERR_PTR(err);
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2534

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2535 2536 2537
	mod = setup_load_info(&info);
	if (IS_ERR(mod)) {
		err = PTR_ERR(mod);
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2538 2539 2540
		goto free_hdr;
	}

L
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2541
	err = check_modinfo(mod, info.sechdrs, info.index.info, info.index.vers);
2542
	if (err)
L
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2543
		goto free_hdr;
2544

L
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2545
	/* Now copy in args */
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2546 2547 2548
	info.args = strndup_user(uargs, ~0UL >> 1);
	if (IS_ERR(info.args)) {
		err = PTR_ERR(info.args);
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2549 2550
		goto free_hdr;
	}
2551

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2552
	strmap = kzalloc(BITS_TO_LONGS(info.sechdrs[info.index.str].sh_size)
2553 2554 2555 2556 2557 2558
			 * sizeof(long), GFP_KERNEL);
	if (!strmap) {
		err = -ENOMEM;
		goto free_mod;
	}

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2559 2560 2561
	mod->state = MODULE_STATE_COMING;

	/* Allow arches to frob section contents and sizes.  */
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2562
	err = module_frob_arch_sections(info.hdr, info.sechdrs, info.secstrings, mod);
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2563 2564 2565
	if (err < 0)
		goto free_mod;

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2566
	if (info.index.pcpu) {
L
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2567
		/* We have a special allocation for this section. */
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2568 2569
		err = percpu_modalloc(mod, info.sechdrs[info.index.pcpu].sh_size,
				      info.sechdrs[info.index.pcpu].sh_addralign);
2570
		if (err)
2571
			goto free_mod;
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2572
		info.sechdrs[info.index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
L
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2573
	}
2574 2575
	/* Keep this around for failure path. */
	percpu = mod_percpu(mod);
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2576 2577 2578 2579

	/* 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. */
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2580 2581 2582
	layout_sections(mod, info.hdr, info.sechdrs, info.secstrings);
	symoffs = layout_symtab(mod, info.sechdrs, info.index.sym, info.index.str, info.hdr,
				info.secstrings, &stroffs, strmap);
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2583

2584
	/* Allocate and move to the final place */
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2585
	mod = move_module(mod, info.hdr, info.sechdrs, info.secstrings, info.index.mod);
2586 2587
	if (IS_ERR(mod)) {
		err = PTR_ERR(mod);
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2588 2589 2590 2591
		goto free_percpu;
	}

	/* Now we've moved module, initialize linked lists, etc. */
2592 2593 2594
	err = module_unload_init(mod);
	if (err)
		goto free_init;
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2595

2596 2597
	/* Now we've got everything in the final locations, we can
	 * find optional sections. */
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2598
	find_module_sections(mod, info.hdr, info.sechdrs, info.secstrings);
2599

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2600
	err = check_module_license_and_versions(mod, info.sechdrs);
2601 2602
	if (err)
		goto free_unload;
2603

2604
	/* Set up MODINFO_ATTR fields */
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2605
	setup_modinfo(mod, info.sechdrs, info.index.info);
2606

L
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2607
	/* Fix up syms, so that st_value is a pointer to location. */
L
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2608
	err = simplify_symbols(info.sechdrs, info.index.sym, info.strtab, info.index.vers, info.index.pcpu,
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2609 2610 2611 2612
			       mod);
	if (err < 0)
		goto cleanup;

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2613
	err = apply_relocations(mod, info.hdr, info.sechdrs, info.index.sym, info.index.str);
2614 2615
	if (err < 0)
		goto cleanup;
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2616 2617

  	/* Set up and sort exception table */
L
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2618
	mod->extable = section_objs(info.hdr, info.sechdrs, info.secstrings, "__ex_table",
R
Rusty Russell 已提交
2619 2620
				    sizeof(*mod->extable), &mod->num_exentries);
	sort_extable(mod->extable, mod->extable + mod->num_exentries);
L
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2621 2622

	/* Finally, copy percpu area over. */
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2623 2624
	percpu_modcopy(mod, (void *)info.sechdrs[info.index.pcpu].sh_addr,
		       info.sechdrs[info.index.pcpu].sh_size);
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2625

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2626 2627
	add_kallsyms(mod, info.sechdrs, info.hdr->e_shnum, info.index.sym, info.index.str,
		     symoffs, stroffs, info.secstrings, strmap);
2628 2629
	kfree(strmap);
	strmap = NULL;
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2630

2631
	if (!mod->taints)
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2632
		debug = section_objs(info.hdr, info.sechdrs, info.secstrings, "__verbose",
R
Rusty Russell 已提交
2633
				     sizeof(*debug), &num_debug);
2634

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2635
	err = module_finalize(info.hdr, info.sechdrs, mod);
L
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2636 2637 2638
	if (err < 0)
		goto cleanup;

2639
	flush_module_icache(mod);
2640

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2641
	mod->args = info.args;
R
Rusty Russell 已提交
2642

2643
	/* Now sew it into the lists so we can get lockdep and oops
2644 2645 2646 2647 2648 2649
	 * info during argument parsing.  Noone should access us, since
	 * strong_try_module_get() will fail.
	 * lockdep/oops can run asynchronous, so use the RCU list insertion
	 * function to insert in a way safe to concurrent readers.
	 * The mutex protects against concurrent writers.
	 */
2650
	mutex_lock(&module_mutex);
2651 2652
	if (find_module(mod->name)) {
		err = -EEXIST;
2653
		goto unlock;
2654 2655
	}

2656 2657 2658
	if (debug)
		dynamic_debug_setup(debug, num_debug);

2659 2660 2661
	/* Find duplicate symbols */
	err = verify_export_symbols(mod);
	if (err < 0)
2662
		goto ddebug;
2663

2664
	list_add_rcu(&mod->list, &modules);
2665
	mutex_unlock(&module_mutex);
2666

2667
	err = parse_args(mod->name, mod->args, mod->kp, mod->num_kp, NULL);
L
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2668
	if (err < 0)
2669
		goto unlink;
L
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2670

2671
	err = mod_sysfs_setup(mod, mod->kp, mod->num_kp);
L
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2672
	if (err < 0)
2673
		goto unlink;
2674

L
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2675 2676
	add_sect_attrs(mod, info.hdr->e_shnum, info.secstrings, info.sechdrs);
	add_notes_attrs(mod, info.hdr->e_shnum, info.secstrings, info.sechdrs);
L
Linus Torvalds 已提交
2677 2678

	/* Get rid of temporary copy */
L
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2679
	vfree(info.hdr);
L
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2680

2681 2682
	trace_module_load(mod);

L
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2683 2684 2685
	/* Done! */
	return mod;

2686
 unlink:
2687
	mutex_lock(&module_mutex);
2688 2689
	/* Unlink carefully: kallsyms could be walking list. */
	list_del_rcu(&mod->list);
2690 2691
 ddebug:
	dynamic_debug_remove(debug);
2692
 unlock:
2693
	mutex_unlock(&module_mutex);
2694
	synchronize_sched();
L
Linus Torvalds 已提交
2695 2696
	module_arch_cleanup(mod);
 cleanup:
2697
	free_modinfo(mod);
2698
 free_unload:
L
Linus Torvalds 已提交
2699
	module_unload_free(mod);
2700
 free_init:
L
Linus Torvalds 已提交
2701 2702
	module_free(mod, mod->module_init);
	module_free(mod, mod->module_core);
2703
	/* mod will be freed with core. Don't access it beyond this line! */
L
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2704
 free_percpu:
2705
	free_percpu(percpu);
L
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2706
 free_mod:
L
Linus Torvalds 已提交
2707
	kfree(info.args);
2708
	kfree(strmap);
L
Linus Torvalds 已提交
2709
 free_hdr:
L
Linus Torvalds 已提交
2710
	vfree(info.hdr);
2711
	return ERR_PTR(err);
L
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2712 2713
}

2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724
/* 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
}

L
Linus Torvalds 已提交
2725
/* This is where the real work happens */
2726 2727
SYSCALL_DEFINE3(init_module, void __user *, umod,
		unsigned long, len, const char __user *, uargs)
L
Linus Torvalds 已提交
2728 2729 2730 2731 2732
{
	struct module *mod;
	int ret = 0;

	/* Must have permission */
2733
	if (!capable(CAP_SYS_MODULE) || modules_disabled)
L
Linus Torvalds 已提交
2734 2735 2736 2737
		return -EPERM;

	/* Do all the hard work */
	mod = load_module(umod, len, uargs);
2738
	if (IS_ERR(mod))
L
Linus Torvalds 已提交
2739 2740
		return PTR_ERR(mod);

2741 2742
	blocking_notifier_call_chain(&module_notify_list,
			MODULE_STATE_COMING, mod);
L
Linus Torvalds 已提交
2743

2744
	do_mod_ctors(mod);
L
Linus Torvalds 已提交
2745 2746
	/* Start the module */
	if (mod->init != NULL)
2747
		ret = do_one_initcall(mod->init);
L
Linus Torvalds 已提交
2748 2749 2750 2751
	if (ret < 0) {
		/* Init routine failed: abort.  Try to protect us from
                   buggy refcounters. */
		mod->state = MODULE_STATE_GOING;
2752
		synchronize_sched();
R
Rusty Russell 已提交
2753
		module_put(mod);
2754 2755
		blocking_notifier_call_chain(&module_notify_list,
					     MODULE_STATE_GOING, mod);
R
Rusty Russell 已提交
2756
		free_module(mod);
2757
		wake_up(&module_wq);
L
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2758 2759
		return ret;
	}
2760
	if (ret > 0) {
2761 2762 2763
		printk(KERN_WARNING
"%s: '%s'->init suspiciously returned %d, it should follow 0/-E convention\n"
"%s: loading module anyway...\n",
2764 2765 2766 2767
		       __func__, mod->name, ret,
		       __func__);
		dump_stack();
	}
L
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2768

2769
	/* Now it's a first class citizen!  Wake up anyone waiting for it. */
L
Linus Torvalds 已提交
2770
	mod->state = MODULE_STATE_LIVE;
2771
	wake_up(&module_wq);
2772 2773
	blocking_notifier_call_chain(&module_notify_list,
				     MODULE_STATE_LIVE, mod);
2774

2775 2776 2777
	/* We need to finish all async code before the module init sequence is done */
	async_synchronize_full();

2778
	mutex_lock(&module_mutex);
L
Linus Torvalds 已提交
2779 2780
	/* Drop initial reference. */
	module_put(mod);
2781
	trim_init_extable(mod);
2782 2783 2784
#ifdef CONFIG_KALLSYMS
	mod->num_symtab = mod->core_num_syms;
	mod->symtab = mod->core_symtab;
2785
	mod->strtab = mod->core_strtab;
2786
#endif
L
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2787 2788 2789 2790
	module_free(mod, mod->module_init);
	mod->module_init = NULL;
	mod->init_size = 0;
	mod->init_text_size = 0;
2791
	mutex_unlock(&module_mutex);
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2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807

	return 0;
}

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 $d.
 */
static inline int is_arm_mapping_symbol(const char *str)
{
D
Daniel Walker 已提交
2808
	return str[0] == '$' && strchr("atd", str[1])
L
Linus Torvalds 已提交
2809 2810 2811 2812 2813 2814 2815 2816 2817 2818 2819 2820
	       && (str[2] == '\0' || str[2] == '.');
}

static const char *get_ksymbol(struct module *mod,
			       unsigned long addr,
			       unsigned long *size,
			       unsigned long *offset)
{
	unsigned int i, best = 0;
	unsigned long nextval;

	/* At worse, next value is at end of module */
2821
	if (within_module_init(addr, mod))
L
Linus Torvalds 已提交
2822
		nextval = (unsigned long)mod->module_init+mod->init_text_size;
D
Daniel Walker 已提交
2823
	else
L
Linus Torvalds 已提交
2824 2825 2826
		nextval = (unsigned long)mod->module_core+mod->core_text_size;

	/* Scan for closest preceeding symbol, and next symbol. (ELF
D
Daniel Walker 已提交
2827
	   starts real symbols at 1). */
L
Linus Torvalds 已提交
2828 2829 2830 2831 2832 2833 2834 2835 2836 2837 2838 2839 2840 2841 2842 2843 2844 2845 2846 2847 2848
	for (i = 1; i < mod->num_symtab; i++) {
		if (mod->symtab[i].st_shndx == SHN_UNDEF)
			continue;

		/* We ignore unnamed symbols: they're uninformative
		 * and inserted at a whim. */
		if (mod->symtab[i].st_value <= addr
		    && mod->symtab[i].st_value > mod->symtab[best].st_value
		    && *(mod->strtab + mod->symtab[i].st_name) != '\0'
		    && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
			best = i;
		if (mod->symtab[i].st_value > addr
		    && mod->symtab[i].st_value < nextval
		    && *(mod->strtab + mod->symtab[i].st_name) != '\0'
		    && !is_arm_mapping_symbol(mod->strtab + mod->symtab[i].st_name))
			nextval = mod->symtab[i].st_value;
	}

	if (!best)
		return NULL;

A
Alexey Dobriyan 已提交
2849 2850 2851 2852
	if (size)
		*size = nextval - mod->symtab[best].st_value;
	if (offset)
		*offset = addr - mod->symtab[best].st_value;
L
Linus Torvalds 已提交
2853 2854 2855
	return mod->strtab + mod->symtab[best].st_name;
}

2856 2857
/* For kallsyms to ask for address resolution.  NULL means not found.  Careful
 * not to lock to avoid deadlock on oopses, simply disable preemption. */
2858
const char *module_address_lookup(unsigned long addr,
2859 2860 2861 2862
			    unsigned long *size,
			    unsigned long *offset,
			    char **modname,
			    char *namebuf)
L
Linus Torvalds 已提交
2863 2864
{
	struct module *mod;
2865
	const char *ret = NULL;
L
Linus Torvalds 已提交
2866

2867
	preempt_disable();
2868
	list_for_each_entry_rcu(mod, &modules, list) {
2869 2870
		if (within_module_init(addr, mod) ||
		    within_module_core(addr, mod)) {
2871 2872
			if (modname)
				*modname = mod->name;
2873 2874
			ret = get_ksymbol(mod, addr, size, offset);
			break;
L
Linus Torvalds 已提交
2875 2876
		}
	}
2877 2878 2879 2880 2881
	/* Make a copy in here where it's safe */
	if (ret) {
		strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
		ret = namebuf;
	}
2882
	preempt_enable();
2883
	return ret;
L
Linus Torvalds 已提交
2884 2885
}

2886 2887 2888 2889
int lookup_module_symbol_name(unsigned long addr, char *symname)
{
	struct module *mod;

2890
	preempt_disable();
2891
	list_for_each_entry_rcu(mod, &modules, list) {
2892 2893
		if (within_module_init(addr, mod) ||
		    within_module_core(addr, mod)) {
2894 2895 2896 2897 2898
			const char *sym;

			sym = get_ksymbol(mod, addr, NULL, NULL);
			if (!sym)
				goto out;
2899
			strlcpy(symname, sym, KSYM_NAME_LEN);
2900
			preempt_enable();
2901 2902 2903 2904
			return 0;
		}
	}
out:
2905
	preempt_enable();
2906 2907 2908
	return -ERANGE;
}

2909 2910 2911 2912 2913
int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
			unsigned long *offset, char *modname, char *name)
{
	struct module *mod;

2914
	preempt_disable();
2915
	list_for_each_entry_rcu(mod, &modules, list) {
2916 2917
		if (within_module_init(addr, mod) ||
		    within_module_core(addr, mod)) {
2918 2919 2920 2921 2922 2923
			const char *sym;

			sym = get_ksymbol(mod, addr, size, offset);
			if (!sym)
				goto out;
			if (modname)
2924
				strlcpy(modname, mod->name, MODULE_NAME_LEN);
2925
			if (name)
2926
				strlcpy(name, sym, KSYM_NAME_LEN);
2927
			preempt_enable();
2928 2929 2930 2931
			return 0;
		}
	}
out:
2932
	preempt_enable();
2933 2934 2935
	return -ERANGE;
}

2936 2937
int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
			char *name, char *module_name, int *exported)
L
Linus Torvalds 已提交
2938 2939 2940
{
	struct module *mod;

2941
	preempt_disable();
2942
	list_for_each_entry_rcu(mod, &modules, list) {
L
Linus Torvalds 已提交
2943 2944 2945
		if (symnum < mod->num_symtab) {
			*value = mod->symtab[symnum].st_value;
			*type = mod->symtab[symnum].st_info;
2946
			strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
2947 2948
				KSYM_NAME_LEN);
			strlcpy(module_name, mod->name, MODULE_NAME_LEN);
2949
			*exported = is_exported(name, *value, mod);
2950
			preempt_enable();
2951
			return 0;
L
Linus Torvalds 已提交
2952 2953 2954
		}
		symnum -= mod->num_symtab;
	}
2955
	preempt_enable();
2956
	return -ERANGE;
L
Linus Torvalds 已提交
2957 2958 2959 2960 2961 2962 2963
}

static unsigned long mod_find_symname(struct module *mod, const char *name)
{
	unsigned int i;

	for (i = 0; i < mod->num_symtab; i++)
2964 2965
		if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
		    mod->symtab[i].st_info != 'U')
L
Linus Torvalds 已提交
2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977
			return mod->symtab[i].st_value;
	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. */
2978
	preempt_disable();
L
Linus Torvalds 已提交
2979 2980 2981 2982 2983 2984
	if ((colon = strchr(name, ':')) != NULL) {
		*colon = '\0';
		if ((mod = find_module(name)) != NULL)
			ret = mod_find_symname(mod, colon+1);
		*colon = ':';
	} else {
2985
		list_for_each_entry_rcu(mod, &modules, list)
L
Linus Torvalds 已提交
2986 2987 2988
			if ((ret = mod_find_symname(mod, name)) != 0)
				break;
	}
2989
	preempt_enable();
L
Linus Torvalds 已提交
2990 2991
	return ret;
}
2992 2993 2994 2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010

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;

	list_for_each_entry(mod, &modules, list) {
		for (i = 0; i < mod->num_symtab; i++) {
			ret = fn(data, mod->strtab + mod->symtab[i].st_name,
				 mod, mod->symtab[i].st_value);
			if (ret != 0)
				return ret;
		}
	}
	return 0;
}
L
Linus Torvalds 已提交
3011 3012
#endif /* CONFIG_KALLSYMS */

3013
static char *module_flags(struct module *mod, char *buf)
3014 3015 3016
{
	int bx = 0;

3017 3018 3019
	if (mod->taints ||
	    mod->state == MODULE_STATE_GOING ||
	    mod->state == MODULE_STATE_COMING) {
3020
		buf[bx++] = '(';
A
Andi Kleen 已提交
3021
		if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE))
3022
			buf[bx++] = 'P';
A
Andi Kleen 已提交
3023
		if (mod->taints & (1 << TAINT_FORCED_MODULE))
3024
			buf[bx++] = 'F';
3025
		if (mod->taints & (1 << TAINT_CRAP))
3026
			buf[bx++] = 'C';
3027 3028 3029 3030 3031
		/*
		 * TAINT_FORCED_RMMOD: could be added.
		 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
		 * apply to modules.
		 */
3032 3033 3034 3035 3036 3037 3038

		/* 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++] = '+';
3039 3040 3041 3042 3043 3044 3045
		buf[bx++] = ')';
	}
	buf[bx] = '\0';

	return buf;
}

3046 3047 3048 3049 3050 3051 3052 3053 3054 3055 3056 3057 3058 3059 3060 3061 3062 3063
#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);
}

L
Linus Torvalds 已提交
3064 3065 3066
static int m_show(struct seq_file *m, void *p)
{
	struct module *mod = list_entry(p, struct module, list);
3067 3068
	char buf[8];

3069
	seq_printf(m, "%s %u",
L
Linus Torvalds 已提交
3070 3071 3072 3073 3074 3075 3076 3077 3078 3079 3080
		   mod->name, mod->init_size + mod->core_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. */
	seq_printf(m, " 0x%p", mod->module_core);

3081 3082
	/* Taints info */
	if (mod->taints)
3083
		seq_printf(m, " %s", module_flags(mod, buf));
3084

L
Linus Torvalds 已提交
3085 3086 3087 3088 3089 3090 3091 3092 3093
	seq_printf(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 -.
*/
3094
static const struct seq_operations modules_op = {
L
Linus Torvalds 已提交
3095 3096 3097 3098 3099 3100
	.start	= m_start,
	.next	= m_next,
	.stop	= m_stop,
	.show	= m_show
};

3101 3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120
static int modules_open(struct inode *inode, struct file *file)
{
	return seq_open(file, &modules_op);
}

static const struct file_operations proc_modules_operations = {
	.open		= modules_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= seq_release,
};

static int __init proc_modules_init(void)
{
	proc_create("modules", 0, NULL, &proc_modules_operations);
	return 0;
}
module_init(proc_modules_init);
#endif

L
Linus Torvalds 已提交
3121 3122 3123 3124 3125 3126
/* 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;

R
Rusty Russell 已提交
3127
	preempt_disable();
3128
	list_for_each_entry_rcu(mod, &modules, list) {
L
Linus Torvalds 已提交
3129 3130
		if (mod->num_exentries == 0)
			continue;
D
Daniel Walker 已提交
3131

L
Linus Torvalds 已提交
3132 3133 3134 3135 3136 3137
		e = search_extable(mod->extable,
				   mod->extable + mod->num_exentries - 1,
				   addr);
		if (e)
			break;
	}
R
Rusty Russell 已提交
3138
	preempt_enable();
L
Linus Torvalds 已提交
3139 3140

	/* Now, if we found one, we are running inside it now, hence
D
Daniel Walker 已提交
3141
	   we cannot unload the module, hence no refcnt needed. */
L
Linus Torvalds 已提交
3142 3143 3144
	return e;
}

3145
/*
R
Rusty Russell 已提交
3146 3147 3148 3149 3150
 * 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).
3151
 */
R
Rusty Russell 已提交
3152
bool is_module_address(unsigned long addr)
3153
{
R
Rusty Russell 已提交
3154
	bool ret;
3155

R
Rusty Russell 已提交
3156
	preempt_disable();
R
Rusty Russell 已提交
3157
	ret = __module_address(addr) != NULL;
R
Rusty Russell 已提交
3158
	preempt_enable();
3159

R
Rusty Russell 已提交
3160
	return ret;
3161 3162
}

R
Rusty Russell 已提交
3163 3164 3165 3166 3167 3168 3169
/*
 * __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.
 */
3170
struct module *__module_address(unsigned long addr)
L
Linus Torvalds 已提交
3171 3172 3173
{
	struct module *mod;

3174 3175 3176
	if (addr < module_addr_min || addr > module_addr_max)
		return NULL;

3177
	list_for_each_entry_rcu(mod, &modules, list)
R
Rusty Russell 已提交
3178 3179
		if (within_module_core(addr, mod)
		    || within_module_init(addr, mod))
L
Linus Torvalds 已提交
3180 3181 3182
			return mod;
	return NULL;
}
3183
EXPORT_SYMBOL_GPL(__module_address);
L
Linus Torvalds 已提交
3184

R
Rusty Russell 已提交
3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221
/*
 * 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->module_init, mod->init_text_size)
		    && !within(addr, mod->module_core, mod->core_text_size))
			mod = NULL;
	}
	return mod;
}
3222
EXPORT_SYMBOL_GPL(__module_text_address);
R
Rusty Russell 已提交
3223

L
Linus Torvalds 已提交
3224 3225 3226 3227
/* Don't grab lock, we're oopsing. */
void print_modules(void)
{
	struct module *mod;
3228
	char buf[8];
L
Linus Torvalds 已提交
3229

3230
	printk(KERN_DEFAULT "Modules linked in:");
3231 3232 3233
	/* Most callers should already have preempt disabled, but make sure */
	preempt_disable();
	list_for_each_entry_rcu(mod, &modules, list)
3234
		printk(" %s%s", mod->name, module_flags(mod, buf));
3235
	preempt_enable();
3236 3237
	if (last_unloaded_module[0])
		printk(" [last unloaded: %s]", last_unloaded_module);
L
Linus Torvalds 已提交
3238 3239 3240 3241
	printk("\n");
}

#ifdef CONFIG_MODVERSIONS
3242 3243 3244 3245 3246 3247 3248 3249 3250 3251
/* 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 *tp)
{
}
EXPORT_SYMBOL(module_layout);
L
Linus Torvalds 已提交
3252
#endif
M
Mathieu Desnoyers 已提交
3253

M
Mathieu Desnoyers 已提交
3254 3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299
#ifdef CONFIG_TRACEPOINTS
void module_update_tracepoints(void)
{
	struct module *mod;

	mutex_lock(&module_mutex);
	list_for_each_entry(mod, &modules, list)
		if (!mod->taints)
			tracepoint_update_probe_range(mod->tracepoints,
				mod->tracepoints + mod->num_tracepoints);
	mutex_unlock(&module_mutex);
}

/*
 * Returns 0 if current not found.
 * Returns 1 if current found.
 */
int module_get_iter_tracepoints(struct tracepoint_iter *iter)
{
	struct module *iter_mod;
	int found = 0;

	mutex_lock(&module_mutex);
	list_for_each_entry(iter_mod, &modules, list) {
		if (!iter_mod->taints) {
			/*
			 * Sorted module list
			 */
			if (iter_mod < iter->module)
				continue;
			else if (iter_mod > iter->module)
				iter->tracepoint = NULL;
			found = tracepoint_get_iter_range(&iter->tracepoint,
				iter_mod->tracepoints,
				iter_mod->tracepoints
					+ iter_mod->num_tracepoints);
			if (found) {
				iter->module = iter_mod;
				break;
			}
		}
	}
	mutex_unlock(&module_mutex);
	return found;
}
#endif