module.c 60.8 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>
#include <linux/init.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>
#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/unwind.h>
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#include <asm/uaccess.h>
#include <asm/semaphore.h>
#include <asm/cacheflush.h>
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#include <linux/license.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))

/* Protects module list */
static DEFINE_SPINLOCK(modlist_lock);

/* List of modules, protected by module_mutex AND modlist_lock */
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static DEFINE_MUTEX(module_mutex);
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static LIST_HEAD(modules);

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static BLOCKING_NOTIFIER_HEAD(module_notify_list);
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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);

/* We require a truly strong try_module_get() */
static inline int strong_try_module_get(struct module *mod)
{
	if (mod && mod->state == MODULE_STATE_COMING)
		return 0;
	return try_module_get(mod);
}

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

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/* A thread that wants to hold a reference to a module only while it
 * is running can call ths to safely exit.
 * nfsd and lockd use this.
 */
void __module_put_and_exit(struct module *mod, long code)
{
	module_put(mod);
	do_exit(code);
}
EXPORT_SYMBOL(__module_put_and_exit);
	
/* 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;
}

/* 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 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[];
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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extern const unsigned long __start___kcrctab_unused[];
extern const unsigned long __start___kcrctab_unused_gpl[];
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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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/* 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;
}

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static void printk_unused_warning(const char *name)
{
	printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
		"however this module is using it.\n", 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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/* Find a symbol, return value, crc and module which owns it */
static unsigned long __find_symbol(const char *name,
				   struct module **owner,
				   const unsigned long **crc,
				   int gplok)
{
	struct module *mod;
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	const struct kernel_symbol *ks;
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	/* Core kernel first. */ 
	*owner = NULL;
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	ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
	if (ks) {
		*crc = symversion(__start___kcrctab, (ks - __start___ksymtab));
		return ks->value;
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	}
	if (gplok) {
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		ks = lookup_symbol(name, __start___ksymtab_gpl,
					 __stop___ksymtab_gpl);
		if (ks) {
			*crc = symversion(__start___kcrctab_gpl,
					  (ks - __start___ksymtab_gpl));
			return ks->value;
		}
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	}
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	ks = lookup_symbol(name, __start___ksymtab_gpl_future,
				 __stop___ksymtab_gpl_future);
	if (ks) {
		if (!gplok) {
			printk(KERN_WARNING "Symbol %s is being used "
			       "by a non-GPL module, which will not "
			       "be allowed in the future\n", name);
			printk(KERN_WARNING "Please see the file "
			       "Documentation/feature-removal-schedule.txt "
			       "in the kernel source tree for more "
			       "details.\n");
		}
		*crc = symversion(__start___kcrctab_gpl_future,
				  (ks - __start___ksymtab_gpl_future));
		return ks->value;
	}
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	ks = lookup_symbol(name, __start___ksymtab_unused,
				 __stop___ksymtab_unused);
	if (ks) {
		printk_unused_warning(name);
		*crc = symversion(__start___kcrctab_unused,
				  (ks - __start___ksymtab_unused));
		return ks->value;
	}

	if (gplok)
		ks = lookup_symbol(name, __start___ksymtab_unused_gpl,
				 __stop___ksymtab_unused_gpl);
	if (ks) {
		printk_unused_warning(name);
		*crc = symversion(__start___kcrctab_unused_gpl,
				  (ks - __start___ksymtab_unused_gpl));
		return ks->value;
	}

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	/* Now try modules. */ 
	list_for_each_entry(mod, &modules, list) {
		*owner = mod;
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		ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
		if (ks) {
			*crc = symversion(mod->crcs, (ks - mod->syms));
			return ks->value;
		}
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		if (gplok) {
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			ks = lookup_symbol(name, mod->gpl_syms,
					   mod->gpl_syms + mod->num_gpl_syms);
			if (ks) {
				*crc = symversion(mod->gpl_crcs,
						  (ks - mod->gpl_syms));
				return ks->value;
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			}
		}
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		ks = lookup_symbol(name, mod->unused_syms, mod->unused_syms + mod->num_unused_syms);
		if (ks) {
			printk_unused_warning(name);
			*crc = symversion(mod->unused_crcs, (ks - mod->unused_syms));
			return ks->value;
		}

		if (gplok) {
			ks = lookup_symbol(name, mod->unused_gpl_syms,
					   mod->unused_gpl_syms + mod->num_unused_gpl_syms);
			if (ks) {
				printk_unused_warning(name);
				*crc = symversion(mod->unused_gpl_crcs,
						  (ks - mod->unused_gpl_syms));
				return ks->value;
			}
		}
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		ks = lookup_symbol(name, mod->gpl_future_syms,
				   (mod->gpl_future_syms +
				    mod->num_gpl_future_syms));
		if (ks) {
			if (!gplok) {
				printk(KERN_WARNING "Symbol %s is being used "
				       "by a non-GPL module, which will not "
				       "be allowed in the future\n", name);
				printk(KERN_WARNING "Please see the file "
				       "Documentation/feature-removal-schedule.txt "
				       "in the kernel source tree for more "
				       "details.\n");
			}
			*crc = symversion(mod->gpl_future_crcs,
					  (ks - mod->gpl_future_syms));
			return ks->value;
		}
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	}
	DEBUGP("Failed to find symbol %s\n", name);
 	return 0;
}

/* Search for module by name: must hold module_mutex. */
static struct module *find_module(const char *name)
{
	struct module *mod;

	list_for_each_entry(mod, &modules, list) {
		if (strcmp(mod->name, name) == 0)
			return mod;
	}
	return NULL;
}

#ifdef CONFIG_SMP
/* Number of blocks used and allocated. */
static unsigned int pcpu_num_used, pcpu_num_allocated;
/* Size of each block.  -ve means used. */
static int *pcpu_size;

static int split_block(unsigned int i, unsigned short size)
{
	/* Reallocation required? */
	if (pcpu_num_used + 1 > pcpu_num_allocated) {
		int *new = kmalloc(sizeof(new[0]) * pcpu_num_allocated*2,
				   GFP_KERNEL);
		if (!new)
			return 0;

		memcpy(new, pcpu_size, sizeof(new[0])*pcpu_num_allocated);
		pcpu_num_allocated *= 2;
		kfree(pcpu_size);
		pcpu_size = new;
	}

	/* Insert a new subblock */
	memmove(&pcpu_size[i+1], &pcpu_size[i],
		sizeof(pcpu_size[0]) * (pcpu_num_used - i));
	pcpu_num_used++;

	pcpu_size[i+1] -= size;
	pcpu_size[i] = size;
	return 1;
}

static inline unsigned int block_size(int val)
{
	if (val < 0)
		return -val;
	return val;
}

/* Created by linker magic */
extern char __per_cpu_start[], __per_cpu_end[];

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static void *percpu_modalloc(unsigned long size, unsigned long align,
			     const char *name)
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{
	unsigned long extra;
	unsigned int i;
	void *ptr;

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	if (align > SMP_CACHE_BYTES) {
		printk(KERN_WARNING "%s: per-cpu alignment %li > %i\n",
		       name, align, SMP_CACHE_BYTES);
		align = SMP_CACHE_BYTES;
	}
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	ptr = __per_cpu_start;
	for (i = 0; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
		/* Extra for alignment requirement. */
		extra = ALIGN((unsigned long)ptr, align) - (unsigned long)ptr;
		BUG_ON(i == 0 && extra != 0);

		if (pcpu_size[i] < 0 || pcpu_size[i] < extra + size)
			continue;

		/* Transfer extra to previous block. */
		if (pcpu_size[i-1] < 0)
			pcpu_size[i-1] -= extra;
		else
			pcpu_size[i-1] += extra;
		pcpu_size[i] -= extra;
		ptr += extra;

		/* Split block if warranted */
		if (pcpu_size[i] - size > sizeof(unsigned long))
			if (!split_block(i, size))
				return NULL;

		/* Mark allocated */
		pcpu_size[i] = -pcpu_size[i];
		return ptr;
	}

	printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n",
	       size);
	return NULL;
}

static void percpu_modfree(void *freeme)
{
	unsigned int i;
	void *ptr = __per_cpu_start + block_size(pcpu_size[0]);

	/* First entry is core kernel percpu data. */
	for (i = 1; i < pcpu_num_used; ptr += block_size(pcpu_size[i]), i++) {
		if (ptr == freeme) {
			pcpu_size[i] = -pcpu_size[i];
			goto free;
		}
	}
	BUG();

 free:
	/* Merge with previous? */
	if (pcpu_size[i-1] >= 0) {
		pcpu_size[i-1] += pcpu_size[i];
		pcpu_num_used--;
		memmove(&pcpu_size[i], &pcpu_size[i+1],
			(pcpu_num_used - i) * sizeof(pcpu_size[0]));
		i--;
	}
	/* Merge with next? */
	if (i+1 < pcpu_num_used && pcpu_size[i+1] >= 0) {
		pcpu_size[i] += pcpu_size[i+1];
		pcpu_num_used--;
		memmove(&pcpu_size[i+1], &pcpu_size[i+2],
			(pcpu_num_used - (i+1)) * sizeof(pcpu_size[0]));
	}
}

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

static int percpu_modinit(void)
{
	pcpu_num_used = 2;
	pcpu_num_allocated = 2;
	pcpu_size = kmalloc(sizeof(pcpu_size[0]) * pcpu_num_allocated,
			    GFP_KERNEL);
	/* Static in-kernel percpu data (used). */
	pcpu_size[0] = -ALIGN(__per_cpu_end-__per_cpu_start, SMP_CACHE_BYTES);
	/* Free room. */
	pcpu_size[1] = PERCPU_ENOUGH_ROOM + pcpu_size[0];
	if (pcpu_size[1] < 0) {
		printk(KERN_ERR "No per-cpu room for modules.\n");
		pcpu_num_used = 1;
	}

	return 0;
}	
__initcall(percpu_modinit);
#else /* ... !CONFIG_SMP */
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static inline void *percpu_modalloc(unsigned long size, unsigned long align,
				    const char *name)
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{
	return NULL;
}
static inline void percpu_modfree(void *pcpuptr)
{
	BUG();
}
static inline unsigned int find_pcpusec(Elf_Ehdr *hdr,
					Elf_Shdr *sechdrs,
					const char *secstrings)
{
	return 0;
}
static inline void percpu_modcopy(void *pcpudst, const void *src,
				  unsigned long size)
{
	/* pcpusec should be 0, and size of that section should be 0. */
	BUG_ON(size != 0);
}
#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)                  \
{                                                                     \
        kfree(mod->field);                                            \
        mod->field = NULL;                                            \
}                                                                     \
static struct module_attribute modinfo_##field = {                    \
	.attr = { .name = __stringify(field), .mode = 0444,           \
		  .owner = THIS_MODULE },                             \
	.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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#ifdef CONFIG_MODULE_UNLOAD
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/* Init the unload section of the module. */
static void module_unload_init(struct module *mod)
{
	unsigned int i;

	INIT_LIST_HEAD(&mod->modules_which_use_me);
	for (i = 0; i < NR_CPUS; i++)
		local_set(&mod->ref[i].count, 0);
	/* Hold reference count during initialization. */
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	local_set(&mod->ref[raw_smp_processor_id()].count, 1);
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	/* Backwards compatibility macros put refcount during init. */
	mod->waiter = current;
}

/* modules using other modules */
struct module_use
{
	struct list_head list;
	struct module *module_which_uses;
};

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

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

/* Module a uses b */
static int use_module(struct module *a, struct module *b)
{
	struct module_use *use;
	if (b == NULL || already_uses(a, b)) return 1;

	if (!strong_try_module_get(b))
		return 0;

	DEBUGP("Allocating new usage for %s.\n", a->name);
	use = kmalloc(sizeof(*use), GFP_ATOMIC);
	if (!use) {
		printk("%s: out of memory loading\n", a->name);
		module_put(b);
		return 0;
	}

	use->module_which_uses = a;
	list_add(&use->list, &b->modules_which_use_me);
	return 1;
}

/* Clear the unload stuff of the module. */
static void module_unload_free(struct module *mod)
{
	struct module *i;

	list_for_each_entry(i, &modules, list) {
		struct module_use *use;

		list_for_each_entry(use, &i->modules_which_use_me, list) {
			if (use->module_which_uses == mod) {
				DEBUGP("%s unusing %s\n", mod->name, i->name);
				module_put(i);
				list_del(&use->list);
				kfree(use);
				/* There can be at most one match. */
				break;
			}
		}
	}
}

#ifdef CONFIG_MODULE_FORCE_UNLOAD
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static inline int try_force_unload(unsigned int flags)
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{
	int ret = (flags & O_TRUNC);
	if (ret)
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		add_taint(TAINT_FORCED_RMMOD);
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	return ret;
}
#else
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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;

	/* If it's not unused, quit unless we are told to block. */
	if ((sref->flags & O_NONBLOCK) && module_refcount(sref->mod) != 0) {
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		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)
{
	struct stopref sref = { mod, flags, forced };

	return stop_machine_run(__try_stop_module, &sref, NR_CPUS);
}

unsigned int module_refcount(struct module *mod)
{
	unsigned int i, total = 0;

	for (i = 0; i < NR_CPUS; i++)
		total += local_read(&mod->ref[i].count);
	return total;
}
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)
{
	/* Since we might sleep for some time, drop the semaphore first */
640
	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;
649
	mutex_lock(&module_mutex);
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}

asmlinkage long
sys_delete_module(const char __user *name_user, unsigned int flags)
{
	struct module *mod;
	char name[MODULE_NAME_LEN];
	int ret, forced = 0;

	if (!capable(CAP_SYS_MODULE))
		return -EPERM;

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

666
	if (mutex_lock_interruptible(&module_mutex) != 0)
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		return -EINTR;

	mod = find_module(name);
	if (!mod) {
		ret = -ENOENT;
		goto out;
	}

	if (!list_empty(&mod->modules_which_use_me)) {
		/* 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 */
	if ((mod->init != NULL && mod->exit == NULL)
	    || mod->unsafe) {
693
		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);

	/* Final destruction now noone is using it. */
	if (mod->exit != NULL) {
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		mutex_unlock(&module_mutex);
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		mod->exit();
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		mutex_lock(&module_mutex);
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	}
	free_module(mod);

 out:
722
	mutex_unlock(&module_mutex);
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	return ret;
}

static void print_unload_info(struct seq_file *m, struct module *mod)
{
	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. */
	list_for_each_entry(use, &mod->modules_which_use_me, list) {
		printed_something = 1;
		seq_printf(m, "%s,", use->module_which_uses->name);
	}

	if (mod->unsafe) {
		printed_something = 1;
		seq_printf(m, "[unsafe],");
	}

	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;
	unsigned long flags;
	const unsigned long *crc;

	spin_lock_irqsave(&modlist_lock, flags);
	if (!__find_symbol(symbol, &owner, &crc, 1))
		BUG();
	module_put(owner);
	spin_unlock_irqrestore(&modlist_lock, flags);
}
EXPORT_SYMBOL(__symbol_put);

void symbol_put_addr(void *addr)
{
770
	struct module *modaddr;
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772 773
	if (core_kernel_text((unsigned long)addr))
		return;
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775 776 777
	if (!(modaddr = module_text_address((unsigned long)addr)))
		BUG();
	module_put(modaddr);
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}
EXPORT_SYMBOL_GPL(symbol_put_addr);

static ssize_t show_refcnt(struct module_attribute *mattr,
			   struct module *mod, char *buffer)
{
	/* sysfs holds a reference */
	return sprintf(buffer, "%u\n", module_refcount(mod)-1);
}

static struct module_attribute refcnt = {
	.attr = { .name = "refcnt", .mode = 0444, .owner = THIS_MODULE },
	.show = show_refcnt,
};

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void module_put(struct module *module)
{
	if (module) {
		unsigned int cpu = get_cpu();
		local_dec(&module->ref[cpu].count);
		/* Maybe they're waiting for us to drop reference? */
		if (unlikely(!module_is_live(module)))
			wake_up_process(module->waiter);
		put_cpu();
	}
}
EXPORT_SYMBOL(module_put);

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#else /* !CONFIG_MODULE_UNLOAD */
static void print_unload_info(struct seq_file *m, struct module *mod)
{
	/* We don't know the usage count, or what modules are using. */
	seq_printf(m, " - -");
}

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

static inline int use_module(struct module *a, struct module *b)
{
	return strong_try_module_get(b);
}

static inline void module_unload_init(struct module *mod)
{
}
#endif /* CONFIG_MODULE_UNLOAD */

827 828 829 830 831 832 833 834 835
static struct module_attribute *modinfo_attrs[] = {
	&modinfo_version,
	&modinfo_srcversion,
#ifdef CONFIG_MODULE_UNLOAD
	&refcnt,
#endif
	NULL,
};

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static const char vermagic[] = VERMAGIC_STRING;

#ifdef CONFIG_MODVERSIONS
static int check_version(Elf_Shdr *sechdrs,
			 unsigned int versindex,
			 const char *symname,
			 struct module *mod, 
			 const unsigned long *crc)
{
	unsigned int i, num_versions;
	struct modversion_info *versions;

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

	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;

		if (versions[i].crc == *crc)
			return 1;
		printk("%s: disagrees about version of symbol %s\n",
		       mod->name, symname);
		DEBUGP("Found checksum %lX vs module %lX\n",
		       *crc, versions[i].crc);
		return 0;
	}
	/* Not in module's version table.  OK, but that taints the kernel. */
869
	if (!(tainted & TAINT_FORCED_MODULE))
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		printk("%s: no version for \"%s\" found: kernel tainted.\n",
		       mod->name, symname);
872
	add_taint_module(mod, TAINT_FORCED_MODULE);
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	return 1;
}

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

	if (!__find_symbol("struct_module", &owner, &crc, 1))
		BUG();
	return check_version(sechdrs, versindex, "struct_module", mod,
			     crc);
}

/* First part is kernel version, which we ignore. */
static inline int same_magic(const char *amagic, const char *bmagic)
{
	amagic += strcspn(amagic, " ");
	bmagic += strcspn(bmagic, " ");
	return strcmp(amagic, bmagic) == 0;
}
#else
static inline int check_version(Elf_Shdr *sechdrs,
				unsigned int versindex,
				const char *symname,
				struct module *mod, 
				const unsigned long *crc)
{
	return 1;
}

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

static inline int same_magic(const char *amagic, const char *bmagic)
{
	return strcmp(amagic, bmagic) == 0;
}
#endif /* CONFIG_MODVERSIONS */

/* Resolve a symbol for this module.  I.e. if we find one, record usage.
   Must be holding module_mutex. */
static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
				    unsigned int versindex,
				    const char *name,
				    struct module *mod)
{
	struct module *owner;
	unsigned long ret;
	const unsigned long *crc;

930 931
	ret = __find_symbol(name, &owner, &crc,
			!(mod->taints & TAINT_PROPRIETARY_MODULE));
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	if (ret) {
		/* use_module can fail due to OOM, or module unloading */
		if (!check_version(sechdrs, versindex, name, mod, crc) ||
		    !use_module(mod, owner))
			ret = 0;
	}
	return ret;
}


/*
 * /sys/module/foo/sections stuff
 * J. Corbet <corbet@lwn.net>
 */
#ifdef CONFIG_KALLSYMS
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);
}

955 956 957 958 959 960 961 962 963
static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
{
	int section;

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

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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;
	
	/* Count loaded sections and allocate structures */
	for (i = 0; i < nsect; i++)
		if (sechdrs[i].sh_flags & SHF_ALLOC)
			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]);
980 981
	sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
	if (sect_attrs == NULL)
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		return;

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

988
	sect_attrs->nsections = 0;
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	sattr = &sect_attrs->attrs[0];
	gattr = &sect_attrs->grp.attrs[0];
	for (i = 0; i < nsect; i++) {
		if (! (sechdrs[i].sh_flags & SHF_ALLOC))
			continue;
		sattr->address = sechdrs[i].sh_addr;
995 996 997 998 999
		sattr->name = kstrdup(secstrings + sechdrs[i].sh_name,
					GFP_KERNEL);
		if (sattr->name == NULL)
			goto out;
		sect_attrs->nsections++;
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		sattr->mattr.show = module_sect_show;
		sattr->mattr.store = NULL;
		sattr->mattr.attr.name = sattr->name;
		sattr->mattr.attr.owner = mod;
		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:
1015
	free_sect_attrs(sect_attrs);
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}

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. */
1025
		free_sect_attrs(mod->sect_attrs);
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		mod->sect_attrs = NULL;
	}
}

#else
1031

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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)
{
}
#endif /* CONFIG_KALLSYMS */

1042 1043 1044
static int module_add_modinfo_attrs(struct module *mod)
{
	struct module_attribute *attr;
1045
	struct module_attribute *temp_attr;
1046 1047 1048
	int error = 0;
	int i;

1049 1050 1051 1052 1053 1054 1055
	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;
1056 1057
	for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
		if (!attr->test ||
1058 1059 1060 1061 1062 1063
		    (attr->test && attr->test(mod))) {
			memcpy(temp_attr, attr, sizeof(*temp_attr));
			temp_attr->attr.owner = mod;
			error = sysfs_create_file(&mod->mkobj.kobj,&temp_attr->attr);
			++temp_attr;
		}
1064 1065 1066 1067 1068 1069 1070 1071 1072
	}
	return error;
}

static void module_remove_modinfo_attrs(struct module *mod)
{
	struct module_attribute *attr;
	int i;

1073 1074 1075 1076
	for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
		/* pick a field to test for end of list */
		if (!attr->attr.name)
			break;
1077
		sysfs_remove_file(&mod->mkobj.kobj,&attr->attr);
1078 1079
		if (attr->free)
			attr->free(mod);
1080
	}
1081
	kfree(mod->modinfo_attrs);
1082
}
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static int mod_sysfs_setup(struct module *mod,
			   struct kernel_param *kparam,
			   unsigned int num_params)
{
	int err;

1090 1091 1092 1093 1094 1095
	if (!module_subsys.kset.subsys) {
		printk(KERN_ERR "%s: module_subsys not initialized\n",
		       mod->name);
		err = -EINVAL;
		goto out;
	}
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	memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
	err = kobject_set_name(&mod->mkobj.kobj, "%s", mod->name);
	if (err)
		goto out;
	kobj_set_kset_s(&mod->mkobj, module_subsys);
	mod->mkobj.mod = mod;
1102 1103 1104 1105

	/* delay uevent until full sysfs population */
	kobject_init(&mod->mkobj.kobj);
	err = kobject_add(&mod->mkobj.kobj);
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	if (err)
		goto out;

1109 1110 1111 1112
	mod->drivers_dir = kobject_add_dir(&mod->mkobj.kobj, "drivers");
	if (!mod->drivers_dir)
		goto out_unreg;

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	err = module_param_sysfs_setup(mod, kparam, num_params);
	if (err)
1115
		goto out_unreg_drivers;
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1117 1118
	err = module_add_modinfo_attrs(mod);
	if (err)
1119
		goto out_unreg_param;
1120

1121
	kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
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	return 0;

1124 1125 1126 1127
out_unreg_drivers:
	kobject_unregister(mod->drivers_dir);
out_unreg_param:
	module_param_sysfs_remove(mod);
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out_unreg:
1129 1130
	kobject_del(&mod->mkobj.kobj);
	kobject_put(&mod->mkobj.kobj);
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out:
	return err;
}

static void mod_kobject_remove(struct module *mod)
{
1137
	module_remove_modinfo_attrs(mod);
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	module_param_sysfs_remove(mod);
1139
	kobject_unregister(mod->drivers_dir);
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	kobject_unregister(&mod->mkobj.kobj);
}

/*
 * 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;
}

/* Free a module, remove from lists, etc (must hold module mutex). */
static void free_module(struct module *mod)
{
	/* Delete from various lists */
	stop_machine_run(__unlink_module, mod, NR_CPUS);
	remove_sect_attrs(mod);
	mod_kobject_remove(mod);

1163 1164
	unwind_remove_table(mod->unwind_info, 0);

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	/* Arch-specific cleanup. */
	module_arch_cleanup(mod);

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

	/* This may be NULL, but that's OK */
	module_free(mod, mod->module_init);
	kfree(mod->args);
	if (mod->percpu)
		percpu_modfree(mod->percpu);

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	/* Free lock-classes: */
	lockdep_free_key_range(mod->module_core, mod->core_size);

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	/* Finally, free the core (containing the module structure) */
	module_free(mod, mod->module_core);
}

void *__symbol_get(const char *symbol)
{
	struct module *owner;
	unsigned long value, flags;
	const unsigned long *crc;

	spin_lock_irqsave(&modlist_lock, flags);
	value = __find_symbol(symbol, &owner, &crc, 1);
	if (value && !strong_try_module_get(owner))
		value = 0;
	spin_unlock_irqrestore(&modlist_lock, flags);

	return (void *)value;
}
EXPORT_SYMBOL_GPL(__symbol_get);

1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232
/*
 * Ensure that an exported symbol [global namespace] does not already exist
 * in the Kernel or in some other modules exported symbol table.
 */
static int verify_export_symbols(struct module *mod)
{
	const char *name = NULL;
	unsigned long i, ret = 0;
	struct module *owner;
	const unsigned long *crc;

	for (i = 0; i < mod->num_syms; i++)
	        if (__find_symbol(mod->syms[i].name, &owner, &crc, 1)) {
			name = mod->syms[i].name;
			ret = -ENOEXEC;
			goto dup;
		}

	for (i = 0; i < mod->num_gpl_syms; i++)
	        if (__find_symbol(mod->gpl_syms[i].name, &owner, &crc, 1)) {
			name = mod->gpl_syms[i].name;
			ret = -ENOEXEC;
			goto dup;
		}

dup:
	if (ret)
		printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
			mod->name, name, module_name(owner));

	return ret;
}

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/* Change all symbols so that sh_value encodes the pointer directly. */
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;

	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:
			sym[i].st_value
			  = resolve_symbol(sechdrs, versindex,
					   strtab + sym[i].st_name, mod);

			/* Ok if resolved.  */
			if (sym[i].st_value != 0)
				break;
			/* Ok if weak.  */
			if (ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
				break;

			printk(KERN_WARNING "%s: Unknown symbol %s\n",
			       mod->name, strtab + sym[i].st_name);
			ret = -ENOENT;
			break;

		default:
			/* Divert to percpu allocation if a percpu var. */
			if (sym[i].st_shndx == pcpuindex)
				secbase = (unsigned long)mod->percpu;
			else
				secbase = sechdrs[sym[i].st_shndx].sh_addr;
			sym[i].st_value += secbase;
			break;
		}
	}

	return ret;
}

/* Update size with this section: return offset. */
static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
{
	long ret;

	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
			    || strncmp(secstrings + s->sh_name,
				       ".init", 5) == 0)
				continue;
			s->sh_entsize = get_offset(&mod->core_size, s);
			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
			    || strncmp(secstrings + s->sh_name,
				       ".init", 5) != 0)
				continue;
			s->sh_entsize = (get_offset(&mod->init_size, s)
					 | 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";

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	if (!license_is_gpl_compatible(license)) {
		if (!(tainted & TAINT_PROPRIETARY_MODULE))
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			printk(KERN_WARNING "%s: module license '%s' taints "
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				"kernel.\n", mod->name, license);
		add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
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	}
}

/* Parse tag=value strings from .modinfo section */
static char *next_string(char *string, unsigned long *secsize)
{
	/* Skip non-zero chars */
	while (string[0]) {
		string++;
		if ((*secsize)-- <= 1)
			return NULL;
	}

	/* Skip any zero padding. */
	while (!string[0]) {
		string++;
		if ((*secsize)-- <= 1)
			return NULL;
	}
	return string;
}

static char *get_modinfo(Elf_Shdr *sechdrs,
			 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;
}

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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));
	}
}

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#ifdef CONFIG_KALLSYMS
int is_exported(const char *name, const struct module *mod)
{
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	if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
		return 1;
	else
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		if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
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			return 1;
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		else
			return 0;
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}

/* 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';
	}
	if (strncmp(secstrings + sechdrs[sym->st_shndx].sh_name,
		    ".debug", strlen(".debug")) == 0)
		return 'n';
	return '?';
}

static void add_kallsyms(struct module *mod,
			 Elf_Shdr *sechdrs,
			 unsigned int symindex,
			 unsigned int strindex,
			 const char *secstrings)
{
	unsigned int i;

	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);
}
#else
static inline void add_kallsyms(struct module *mod,
				Elf_Shdr *sechdrs,
				unsigned int symindex,
				unsigned int strindex,
				const char *secstrings)
{
}
#endif /* CONFIG_KALLSYMS */

/* Allocate and load the module: note that size of section 0 is always
   zero, and we rely on this for optional sections. */
static struct module *load_module(void __user *umod,
				  unsigned long len,
				  const char __user *uargs)
{
	Elf_Ehdr *hdr;
	Elf_Shdr *sechdrs;
	char *secstrings, *args, *modmagic, *strtab = NULL;
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	unsigned int i;
	unsigned int symindex = 0;
	unsigned int strindex = 0;
	unsigned int setupindex;
	unsigned int exindex;
	unsigned int exportindex;
	unsigned int modindex;
	unsigned int obsparmindex;
	unsigned int infoindex;
	unsigned int gplindex;
	unsigned int crcindex;
	unsigned int gplcrcindex;
	unsigned int versindex;
	unsigned int pcpuindex;
	unsigned int gplfutureindex;
	unsigned int gplfuturecrcindex;
	unsigned int unwindex = 0;
	unsigned int unusedindex;
	unsigned int unusedcrcindex;
	unsigned int unusedgplindex;
	unsigned int unusedgplcrcindex;
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	struct module *mod;
	long err = 0;
	void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */
	struct exception_table_entry *extable;
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	mm_segment_t old_fs;
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	DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
	       umod, len, uargs);
	if (len < sizeof(*hdr))
		return ERR_PTR(-ENOEXEC);

	/* Suck in entire file: we'll want most of it. */
	/* vmalloc barfs on "unusual" numbers.  Check here */
	if (len > 64 * 1024 * 1024 || (hdr = vmalloc(len)) == NULL)
		return ERR_PTR(-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, 4) != 0
	    || hdr->e_type != ET_REL
	    || !elf_check_arch(hdr)
	    || hdr->e_shentsize != sizeof(*sechdrs)) {
		err = -ENOEXEC;
		goto free_hdr;
	}

	if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr))
		goto truncated;

	/* Convenience variables */
	sechdrs = (void *)hdr + hdr->e_shoff;
	secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
	sechdrs[0].sh_addr = 0;

	for (i = 1; i < hdr->e_shnum; i++) {
		if (sechdrs[i].sh_type != SHT_NOBITS
		    && len < sechdrs[i].sh_offset + sechdrs[i].sh_size)
			goto truncated;

		/* Mark all sections sh_addr with their address in the
		   temporary image. */
		sechdrs[i].sh_addr = (size_t)hdr + sechdrs[i].sh_offset;

		/* Internal symbols and strings. */
		if (sechdrs[i].sh_type == SHT_SYMTAB) {
			symindex = i;
			strindex = sechdrs[i].sh_link;
			strtab = (char *)hdr + sechdrs[strindex].sh_offset;
		}
#ifndef CONFIG_MODULE_UNLOAD
		/* Don't load .exit sections */
		if (strncmp(secstrings+sechdrs[i].sh_name, ".exit", 5) == 0)
			sechdrs[i].sh_flags &= ~(unsigned long)SHF_ALLOC;
#endif
	}

	modindex = find_sec(hdr, sechdrs, secstrings,
			    ".gnu.linkonce.this_module");
	if (!modindex) {
		printk(KERN_WARNING "No module found in object\n");
		err = -ENOEXEC;
		goto free_hdr;
	}
	mod = (void *)sechdrs[modindex].sh_addr;

	if (symindex == 0) {
		printk(KERN_WARNING "%s: module has no symbols (stripped?)\n",
		       mod->name);
		err = -ENOEXEC;
		goto free_hdr;
	}

	/* Optional sections */
	exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab");
	gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl");
1616
	gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future");
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	unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused");
	unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl");
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	crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab");
	gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl");
1621
	gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future");
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	unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused");
	unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl");
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	setupindex = find_sec(hdr, sechdrs, secstrings, "__param");
	exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table");
	obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm");
	versindex = find_sec(hdr, sechdrs, secstrings, "__versions");
	infoindex = find_sec(hdr, sechdrs, secstrings, ".modinfo");
	pcpuindex = find_pcpusec(hdr, sechdrs, secstrings);
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#ifdef ARCH_UNWIND_SECTION_NAME
	unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
#endif
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	/* Don't keep modinfo section */
	sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
#ifdef CONFIG_KALLSYMS
	/* Keep symbol and string tables for decoding later. */
	sechdrs[symindex].sh_flags |= SHF_ALLOC;
	sechdrs[strindex].sh_flags |= SHF_ALLOC;
#endif
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	if (unwindex)
		sechdrs[unwindex].sh_flags |= SHF_ALLOC;
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	/* Check module struct version now, before we try to use module. */
	if (!check_modstruct_version(sechdrs, versindex, mod)) {
		err = -ENOEXEC;
		goto free_hdr;
	}

	modmagic = get_modinfo(sechdrs, infoindex, "vermagic");
	/* This is allowed: modprobe --force will invalidate it. */
	if (!modmagic) {
1653
		add_taint_module(mod, TAINT_FORCED_MODULE);
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		printk(KERN_WARNING "%s: no version magic, tainting kernel.\n",
		       mod->name);
	} else if (!same_magic(modmagic, vermagic)) {
		printk(KERN_ERR "%s: version magic '%s' should be '%s'\n",
		       mod->name, modmagic, vermagic);
		err = -ENOEXEC;
		goto free_hdr;
	}

	/* Now copy in args */
1664 1665 1666
	args = strndup_user(uargs, ~0UL >> 1);
	if (IS_ERR(args)) {
		err = PTR_ERR(args);
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		goto free_hdr;
	}
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	if (find_module(mod->name)) {
		err = -EEXIST;
		goto free_mod;
	}

	mod->state = MODULE_STATE_COMING;

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

	if (pcpuindex) {
		/* We have a special allocation for this section. */
		percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
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					 sechdrs[pcpuindex].sh_addralign,
					 mod->name);
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		if (!percpu) {
			err = -ENOMEM;
			goto free_mod;
		}
		sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
		mod->percpu = percpu;
	}

	/* Determine total sizes, and put offsets in sh_entsize.  For now
	   this is done generically; there doesn't appear to be any
	   special cases for the architectures. */
	layout_sections(mod, hdr, sechdrs, secstrings);

	/* Do the allocs. */
	ptr = module_alloc(mod->core_size);
	if (!ptr) {
		err = -ENOMEM;
		goto free_percpu;
	}
	memset(ptr, 0, mod->core_size);
	mod->module_core = ptr;

	ptr = module_alloc(mod->init_size);
	if (!ptr && mod->init_size) {
		err = -ENOMEM;
		goto free_core;
	}
	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;

	/* Now we've moved module, initialize linked lists, etc. */
	module_unload_init(mod);

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

1747
	if (strcmp(mod->name, "ndiswrapper") == 0)
1748
		add_taint(TAINT_PROPRIETARY_MODULE);
1749 1750
	if (strcmp(mod->name, "driverloader") == 0)
		add_taint_module(mod, TAINT_PROPRIETARY_MODULE);
1751

1752 1753 1754
	/* Set up MODINFO_ATTR fields */
	setup_modinfo(mod, sechdrs, infoindex);

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	/* Fix up syms, so that st_value is a pointer to location. */
	err = simplify_symbols(sechdrs, symindex, strtab, versindex, pcpuindex,
			       mod);
	if (err < 0)
		goto cleanup;

	/* Set up EXPORTed & EXPORT_GPLed symbols (section 0 is 0 length) */
	mod->num_syms = sechdrs[exportindex].sh_size / sizeof(*mod->syms);
	mod->syms = (void *)sechdrs[exportindex].sh_addr;
	if (crcindex)
		mod->crcs = (void *)sechdrs[crcindex].sh_addr;
	mod->num_gpl_syms = sechdrs[gplindex].sh_size / sizeof(*mod->gpl_syms);
	mod->gpl_syms = (void *)sechdrs[gplindex].sh_addr;
	if (gplcrcindex)
		mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr;
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	mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size /
					sizeof(*mod->gpl_future_syms);
1772 1773 1774 1775
	mod->num_unused_syms = sechdrs[unusedindex].sh_size /
					sizeof(*mod->unused_syms);
	mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size /
					sizeof(*mod->unused_gpl_syms);
1776 1777 1778
	mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr;
	if (gplfuturecrcindex)
		mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr;
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1780 1781 1782 1783 1784 1785 1786
	mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr;
	if (unusedcrcindex)
		mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
	mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
	if (unusedgplcrcindex)
		mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr;

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#ifdef CONFIG_MODVERSIONS
	if ((mod->num_syms && !crcindex) || 
1789
	    (mod->num_gpl_syms && !gplcrcindex) ||
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	    (mod->num_gpl_future_syms && !gplfuturecrcindex) ||
	    (mod->num_unused_syms && !unusedcrcindex) ||
	    (mod->num_unused_gpl_syms && !unusedgplcrcindex)) {
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		printk(KERN_WARNING "%s: No versions for exported symbols."
		       " Tainting kernel.\n", mod->name);
1795
		add_taint_module(mod, TAINT_FORCED_MODULE);
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	}
#endif

	/* 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)
			goto cleanup;
	}

1821 1822 1823 1824 1825 1826
        /* Find duplicate symbols */
	err = verify_export_symbols(mod);

	if (err < 0)
		goto cleanup;

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  	/* Set up and sort exception table */
	mod->num_exentries = sechdrs[exindex].sh_size / sizeof(*mod->extable);
	mod->extable = extable = (void *)sechdrs[exindex].sh_addr;
	sort_extable(extable, extable + mod->num_exentries);

	/* Finally, copy percpu area over. */
	percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr,
		       sechdrs[pcpuindex].sh_size);

	add_kallsyms(mod, sechdrs, symindex, strindex, secstrings);

	err = module_finalize(hdr, sechdrs, mod);
	if (err < 0)
		goto cleanup;

1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859
	/* 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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	mod->args = args;
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	if (obsparmindex)
		printk(KERN_WARNING "%s: Ignoring obsolete parameters\n",
		       mod->name);

	/* Size of section 0 is 0, so this works well if no params */
	err = parse_args(mod->name, mod->args,
			 (struct kernel_param *)
			 sechdrs[setupindex].sh_addr,
			 sechdrs[setupindex].sh_size
			 / sizeof(struct kernel_param),
			 NULL);
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	if (err < 0)
		goto arch_cleanup;

	err = mod_sysfs_setup(mod, 
			      (struct kernel_param *)
			      sechdrs[setupindex].sh_addr,
			      sechdrs[setupindex].sh_size
			      / sizeof(struct kernel_param));
	if (err < 0)
		goto arch_cleanup;
	add_sect_attrs(mod, hdr->e_shnum, secstrings, sechdrs);

1884 1885 1886 1887 1888
	/* Size of section 0 is 0, so this works well if no unwind info. */
	mod->unwind_info = unwind_add_table(mod,
	                                    (void *)sechdrs[unwindex].sh_addr,
	                                    sechdrs[unwindex].sh_size);

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	/* Get rid of temporary copy */
	vfree(hdr);

	/* Done! */
	return mod;

 arch_cleanup:
	module_arch_cleanup(mod);
 cleanup:
	module_unload_free(mod);
	module_free(mod, mod->module_init);
 free_core:
	module_free(mod, mod->module_core);
 free_percpu:
	if (percpu)
		percpu_modfree(percpu);
 free_mod:
	kfree(args);
 free_hdr:
	vfree(hdr);
1909
	return ERR_PTR(err);
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 truncated:
	printk(KERN_ERR "Module len %lu truncated\n", len);
	err = -ENOEXEC;
	goto free_hdr;
}

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

/* This is where the real work happens */
asmlinkage long
sys_init_module(void __user *umod,
		unsigned long len,
		const char __user *uargs)
{
	struct module *mod;
	int ret = 0;

	/* Must have permission */
	if (!capable(CAP_SYS_MODULE))
		return -EPERM;

	/* Only one module load at a time, please */
1942
	if (mutex_lock_interruptible(&module_mutex) != 0)
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		return -EINTR;

	/* Do all the hard work */
	mod = load_module(umod, len, uargs);
	if (IS_ERR(mod)) {
1948
		mutex_unlock(&module_mutex);
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		return PTR_ERR(mod);
	}

	/* Now sew it into the lists.  They won't access us, since
           strong_try_module_get() will fail. */
	stop_machine_run(__link_module, mod, NR_CPUS);

	/* Drop lock so they can recurse */
1957
	mutex_unlock(&module_mutex);
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	blocking_notifier_call_chain(&module_notify_list,
			MODULE_STATE_COMING, mod);
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	/* Start the module */
	if (mod->init != NULL)
		ret = mod->init();
	if (ret < 0) {
		/* Init routine failed: abort.  Try to protect us from
                   buggy refcounters. */
		mod->state = MODULE_STATE_GOING;
1969
		synchronize_sched();
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		if (mod->unsafe)
			printk(KERN_ERR "%s: module is now stuck!\n",
			       mod->name);
		else {
			module_put(mod);
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			mutex_lock(&module_mutex);
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			free_module(mod);
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			mutex_unlock(&module_mutex);
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		}
		return ret;
	}

	/* Now it's a first class citizen! */
1983
	mutex_lock(&module_mutex);
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	mod->state = MODULE_STATE_LIVE;
	/* Drop initial reference. */
	module_put(mod);
1987
	unwind_remove_table(mod->unwind_info, 1);
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	module_free(mod, mod->module_init);
	mod->module_init = NULL;
	mod->init_size = 0;
	mod->init_text_size = 0;
1992
	mutex_unlock(&module_mutex);
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	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 $d.
 */
static inline int is_arm_mapping_symbol(const char *str)
{
	return str[0] == '$' && strchr("atd", str[1]) 
	       && (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 */
	if (within(addr, mod->module_init, mod->init_size))
		nextval = (unsigned long)mod->module_init+mod->init_text_size;
	else 
		nextval = (unsigned long)mod->module_core+mod->core_text_size;

	/* Scan for closest preceeding symbol, and next symbol. (ELF
           starts real symbols at 1). */
	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;

	*size = nextval - mod->symtab[best].st_value;
	*offset = addr - mod->symtab[best].st_value;
	return mod->strtab + mod->symtab[best].st_name;
}

/* For kallsyms to ask for address resolution.  NULL means not found.
   We don't lock, as this is used for oops resolution and races are a
   lesser concern. */
const char *module_address_lookup(unsigned long addr,
				  unsigned long *size,
				  unsigned long *offset,
				  char **modname)
{
	struct module *mod;

	list_for_each_entry(mod, &modules, list) {
		if (within(addr, mod->module_init, mod->init_size)
		    || within(addr, mod->module_core, mod->core_size)) {
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			if (modname)
				*modname = mod->name;
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			return get_ksymbol(mod, addr, size, offset);
		}
	}
	return NULL;
}

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struct module *module_get_kallsym(unsigned int symnum, unsigned long *value,
				char *type, char *name, size_t namelen)
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{
	struct module *mod;

2081
	mutex_lock(&module_mutex);
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	list_for_each_entry(mod, &modules, list) {
		if (symnum < mod->num_symtab) {
			*value = mod->symtab[symnum].st_value;
			*type = mod->symtab[symnum].st_info;
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			strlcpy(name, mod->strtab + mod->symtab[symnum].st_name,
				namelen);
2088
			mutex_unlock(&module_mutex);
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			return mod;
		}
		symnum -= mod->num_symtab;
	}
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	mutex_unlock(&module_mutex);
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	return NULL;
}

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

	for (i = 0; i < mod->num_symtab; i++)
2102 2103
		if (strcmp(name, mod->strtab+mod->symtab[i].st_name) == 0 &&
		    mod->symtab[i].st_info != 'U')
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			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. */
	if ((colon = strchr(name, ':')) != NULL) {
		*colon = '\0';
		if ((mod = find_module(name)) != NULL)
			ret = mod_find_symname(mod, colon+1);
		*colon = ':';
	} else {
		list_for_each_entry(mod, &modules, list)
			if ((ret = mod_find_symname(mod, name)) != 0)
				break;
	}
	return ret;
}
#endif /* CONFIG_KALLSYMS */

/* Called by the /proc file system to return a list of modules. */
static void *m_start(struct seq_file *m, loff_t *pos)
{
	struct list_head *i;
	loff_t n = 0;

2136
	mutex_lock(&module_mutex);
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	list_for_each(i, &modules) {
		if (n++ == *pos)
			break;
	}
	if (i == &modules)
		return NULL;
	return i;
}

static void *m_next(struct seq_file *m, void *p, loff_t *pos)
{
	struct list_head *i = p;
	(*pos)++;
	if (i->next == &modules)
		return NULL;
	return i->next;
}

static void m_stop(struct seq_file *m, void *p)
{
2157
	mutex_unlock(&module_mutex);
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}

2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181
static char *taint_flags(unsigned int taints, char *buf)
{
	int bx = 0;

	if (taints) {
		buf[bx++] = '(';
		if (taints & TAINT_PROPRIETARY_MODULE)
			buf[bx++] = 'P';
		if (taints & TAINT_FORCED_MODULE)
			buf[bx++] = 'F';
		/*
		 * TAINT_FORCED_RMMOD: could be added.
		 * TAINT_UNSAFE_SMP, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't
		 * apply to modules.
		 */
		buf[bx++] = ')';
	}
	buf[bx] = '\0';

	return buf;
}

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static int m_show(struct seq_file *m, void *p)
{
	struct module *mod = list_entry(p, struct module, list);
2185 2186
	char buf[8];

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	seq_printf(m, "%s %lu",
		   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);

2199 2200 2201 2202
	/* Taints info */
	if (mod->taints)
		seq_printf(m, " %s", taint_flags(mod->taints, buf));

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	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 -.
*/
2212
const struct seq_operations modules_op = {
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	.start	= m_start,
	.next	= m_next,
	.stop	= m_stop,
	.show	= m_show
};

/* Given an address, look for it in the module exception tables. */
const struct exception_table_entry *search_module_extables(unsigned long addr)
{
	unsigned long flags;
	const struct exception_table_entry *e = NULL;
	struct module *mod;

	spin_lock_irqsave(&modlist_lock, flags);
	list_for_each_entry(mod, &modules, list) {
		if (mod->num_exentries == 0)
			continue;
				
		e = search_extable(mod->extable,
				   mod->extable + mod->num_exentries - 1,
				   addr);
		if (e)
			break;
	}
	spin_unlock_irqrestore(&modlist_lock, flags);

	/* Now, if we found one, we are running inside it now, hence
           we cannot unload the module, hence no refcnt needed. */
	return e;
}

2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266
/*
 * Is this a valid module address?
 */
int is_module_address(unsigned long addr)
{
	unsigned long flags;
	struct module *mod;

	spin_lock_irqsave(&modlist_lock, flags);

	list_for_each_entry(mod, &modules, list) {
		if (within(addr, mod->module_core, mod->core_size)) {
			spin_unlock_irqrestore(&modlist_lock, flags);
			return 1;
		}
	}

	spin_unlock_irqrestore(&modlist_lock, flags);

	return 0;
}


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/* Is this a valid kernel address?  We don't grab the lock: we are oopsing. */
struct module *__module_text_address(unsigned long addr)
{
	struct module *mod;

	list_for_each_entry(mod, &modules, list)
		if (within(addr, mod->module_init, mod->init_text_size)
		    || within(addr, mod->module_core, mod->core_text_size))
			return mod;
	return NULL;
}

struct module *module_text_address(unsigned long addr)
{
	struct module *mod;
	unsigned long flags;

	spin_lock_irqsave(&modlist_lock, flags);
	mod = __module_text_address(addr);
	spin_unlock_irqrestore(&modlist_lock, flags);

	return mod;
}

/* Don't grab lock, we're oopsing. */
void print_modules(void)
{
	struct module *mod;
2295
	char buf[8];
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	printk("Modules linked in:");
	list_for_each_entry(mod, &modules, list)
2299
		printk(" %s%s", mod->name, taint_flags(mod->taints, buf));
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	printk("\n");
}

void module_add_driver(struct module *mod, struct device_driver *drv)
{
2305 2306
	int no_warn;

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	if (!mod || !drv)
		return;

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	/* Don't check return codes; these calls are idempotent */
	no_warn = sysfs_create_link(&drv->kobj, &mod->mkobj.kobj, "module");
	no_warn = sysfs_create_link(mod->drivers_dir, &drv->kobj, drv->name);
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}
EXPORT_SYMBOL(module_add_driver);

void module_remove_driver(struct device_driver *drv)
{
	if (!drv)
		return;
	sysfs_remove_link(&drv->kobj, "module");
2321 2322
	if (drv->owner && drv->owner->drivers_dir)
		sysfs_remove_link(drv->owner->drivers_dir, drv->name);
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}
EXPORT_SYMBOL(module_remove_driver);

#ifdef CONFIG_MODVERSIONS
/* Generate the signature for struct module here, too, for modversions. */
void struct_module(struct module *mod) { return; }
EXPORT_SYMBOL(struct_module);
#endif