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#include <linux/config.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <asm/module.h>
#include <asm/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/smp_lock.h>
#include <asm/pgalloc.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/kmod.h>
#include <linux/seq_file.h>
/*
* Originally by Anonymous (as far as I know...)
* Linux version by Bas Laarhoven <bas@vimec.nl>
* 0.99.14 version by Jon Tombs <jon@gtex02.us.es>,
* Heavily modified by Bjorn Ekwall <bj0rn@blox.se> May 1994 (C)
* Rewritten by Richard Henderson <rth@tamu.edu> Dec 1996
* Add MOD_INITIALIZING Keith Owens <kaos@ocs.com.au> Nov 1999
* Add kallsyms support, Keith Owens <kaos@ocs.com.au> Apr 2000
* Add asm/module support, IA64 has special requirements. Keith Owens <kaos@ocs.com.au> Sep 2000
* Fix assorted bugs in module verification. Keith Owens <kaos@ocs.com.au> Sep 2000
* Fix sys_init_module race, Andrew Morton <andrewm@uow.edu.au> Oct 2000
* http://www.uwsg.iu.edu/hypermail/linux/kernel/0008.3/0379.html
* Replace xxx_module_symbol with inter_module_xxx. Keith Owens <kaos@ocs.com.au> Oct 2000
* Add a module list lock for kernel fault race fixing. Alan Cox <alan@redhat.com>
*
* This source is covered by the GNU GPL, the same as all kernel sources.
*/
#if defined(CONFIG_MODULES) || defined(CONFIG_KALLSYMS)
extern struct module_symbol __start___ksymtab[];
extern struct module_symbol __stop___ksymtab[];
extern const struct exception_table_entry __start___ex_table[];
extern const struct exception_table_entry __stop___ex_table[];
extern const char __start___kallsyms[] __attribute__ ((weak));
extern const char __stop___kallsyms[] __attribute__ ((weak));
struct module kernel_module =
{
size_of_struct: sizeof(struct module),
name: "",
uc: {ATOMIC_INIT(1)},
flags: MOD_RUNNING,
syms: __start___ksymtab,
ex_table_start: __start___ex_table,
ex_table_end: __stop___ex_table,
kallsyms_start: __start___kallsyms,
kallsyms_end: __stop___kallsyms,
};
struct module *module_list = &kernel_module;
#endif /* defined(CONFIG_MODULES) || defined(CONFIG_KALLSYMS) */
/* inter_module functions are always available, even when the kernel is
* compiled without modules. Consumers of inter_module_xxx routines
* will always work, even when both are built into the kernel, this
* approach removes lots of #ifdefs in mainline code.
*/
static struct list_head ime_list = LIST_HEAD_INIT(ime_list);
static spinlock_t ime_lock = SPIN_LOCK_UNLOCKED;
static int kmalloc_failed;
/*
* This lock prevents modifications that might race the kernel fault
* fixups. It does not prevent reader walks that the modules code
* does. The kernel lock does that.
*
* Since vmalloc fault fixups occur in any context this lock is taken
* irqsave at all times.
*/
spinlock_t modlist_lock = SPIN_LOCK_UNLOCKED;
/**
* inter_module_register - register a new set of inter module data.
* @im_name: an arbitrary string to identify the data, must be unique
* @owner: module that is registering the data, always use THIS_MODULE
* @userdata: pointer to arbitrary userdata to be registered
*
* Description: Check that the im_name has not already been registered,
* complain if it has. For new data, add it to the inter_module_entry
* list.
*/
void inter_module_register(const char *im_name, struct module *owner, const void *userdata)
{
struct list_head *tmp;
struct inter_module_entry *ime, *ime_new;
if (!(ime_new = kmalloc(sizeof(*ime), GFP_KERNEL))) {
/* Overloaded kernel, not fatal */
printk(KERN_ERR
"Aiee, inter_module_register: cannot kmalloc entry for '%s'\n",
im_name);
kmalloc_failed = 1;
return;
}
memset(ime_new, 0, sizeof(*ime_new));
ime_new->im_name = im_name;
ime_new->owner = owner;
ime_new->userdata = userdata;
spin_lock(&ime_lock);
list_for_each(tmp, &ime_list) {
ime = list_entry(tmp, struct inter_module_entry, list);
if (strcmp(ime->im_name, im_name) == 0) {
spin_unlock(&ime_lock);
kfree(ime_new);
/* Program logic error, fatal */
printk(KERN_ERR "inter_module_register: duplicate im_name '%s'", im_name);
BUG();
}
}
list_add(&(ime_new->list), &ime_list);
spin_unlock(&ime_lock);
}
/**
* inter_module_unregister - unregister a set of inter module data.
* @im_name: an arbitrary string to identify the data, must be unique
*
* Description: Check that the im_name has been registered, complain if
* it has not. For existing data, remove it from the
* inter_module_entry list.
*/
void inter_module_unregister(const char *im_name)
{
struct list_head *tmp;
struct inter_module_entry *ime;
spin_lock(&ime_lock);
list_for_each(tmp, &ime_list) {
ime = list_entry(tmp, struct inter_module_entry, list);
if (strcmp(ime->im_name, im_name) == 0) {
list_del(&(ime->list));
spin_unlock(&ime_lock);
kfree(ime);
return;
}
}
spin_unlock(&ime_lock);
if (kmalloc_failed) {
printk(KERN_ERR
"inter_module_unregister: no entry for '%s', "
"probably caused by previous kmalloc failure\n",
im_name);
return;
}
else {
/* Program logic error, fatal */
printk(KERN_ERR "inter_module_unregister: no entry for '%s'", im_name);
BUG();
}
}
/**
* inter_module_get - return arbitrary userdata from another module.
* @im_name: an arbitrary string to identify the data, must be unique
*
* Description: If the im_name has not been registered, return NULL.
* Try to increment the use count on the owning module, if that fails
* then return NULL. Otherwise return the userdata.
*/
const void *inter_module_get(const char *im_name)
{
struct list_head *tmp;
struct inter_module_entry *ime;
const void *result = NULL;
spin_lock(&ime_lock);
list_for_each(tmp, &ime_list) {
ime = list_entry(tmp, struct inter_module_entry, list);
if (strcmp(ime->im_name, im_name) == 0) {
if (try_inc_mod_count(ime->owner))
result = ime->userdata;
break;
}
}
spin_unlock(&ime_lock);
return(result);
}
/**
* inter_module_get_request - im get with automatic request_module.
* @im_name: an arbitrary string to identify the data, must be unique
* @modname: module that is expected to register im_name
*
* Description: If inter_module_get fails, do request_module then retry.
*/
const void *inter_module_get_request(const char *im_name, const char *modname)
{
const void *result = inter_module_get(im_name);
if (!result) {
request_module(modname);
result = inter_module_get(im_name);
}
return(result);
}
/**
* inter_module_put - release use of data from another module.
* @im_name: an arbitrary string to identify the data, must be unique
*
* Description: If the im_name has not been registered, complain,
* otherwise decrement the use count on the owning module.
*/
void inter_module_put(const char *im_name)
{
struct list_head *tmp;
struct inter_module_entry *ime;
spin_lock(&ime_lock);
list_for_each(tmp, &ime_list) {
ime = list_entry(tmp, struct inter_module_entry, list);
if (strcmp(ime->im_name, im_name) == 0) {
if (ime->owner)
__MOD_DEC_USE_COUNT(ime->owner);
spin_unlock(&ime_lock);
return;
}
}
spin_unlock(&ime_lock);
printk(KERN_ERR "inter_module_put: no entry for '%s'", im_name);
BUG();
}
#if defined(CONFIG_MODULES) /* The rest of the source */
static long get_mod_name(const char *user_name, char **buf);
static void put_mod_name(char *buf);
struct module *find_module(const char *name);
void free_module(struct module *, int tag_freed);
/*
* Called at boot time
*/
void __init init_modules(void)
{
kernel_module.nsyms = __stop___ksymtab - __start___ksymtab;
arch_init_modules(&kernel_module);
}
/*
* Copy the name of a module from user space.
*/
static inline long
get_mod_name(const char *user_name, char **buf)
{
unsigned long page;
long retval;
page = __get_free_page(GFP_KERNEL);
if (!page)
return -ENOMEM;
retval = strncpy_from_user((char *)page, user_name, PAGE_SIZE);
if (retval > 0) {
if (retval < PAGE_SIZE) {
*buf = (char *)page;
return retval;
}
retval = -ENAMETOOLONG;
} else if (!retval)
retval = -EINVAL;
free_page(page);
return retval;
}
static inline void
put_mod_name(char *buf)
{
free_page((unsigned long)buf);
}
/*
* Allocate space for a module.
*/
asmlinkage unsigned long
sys_create_module(const char *name_user, size_t size)
{
char *name;
long namelen, error;
struct module *mod;
unsigned long flags;
if (!capable(CAP_SYS_MODULE))
return -EPERM;
lock_kernel();
if ((namelen = get_mod_name(name_user, &name)) < 0) {
error = namelen;
goto err0;
}
if (size < sizeof(struct module)+namelen) {
error = -EINVAL;
goto err1;
}
if (find_module(name) != NULL) {
error = -EEXIST;
goto err1;
}
if ((mod = (struct module *)module_map(size)) == NULL) {
error = -ENOMEM;
goto err1;
}
memset(mod, 0, sizeof(*mod));
mod->size_of_struct = sizeof(*mod);
mod->name = (char *)(mod + 1);
mod->size = size;
memcpy((char*)(mod+1), name, namelen+1);
put_mod_name(name);
spin_lock_irqsave(&modlist_lock, flags);
mod->next = module_list;
module_list = mod; /* link it in */
spin_unlock_irqrestore(&modlist_lock, flags);
error = (long) mod;
goto err0;
err1:
put_mod_name(name);
err0:
unlock_kernel();
return error;
}
/*
* Initialize a module.
*/
asmlinkage long
sys_init_module(const char *name_user, struct module *mod_user)
{
struct module mod_tmp, *mod;
char *name, *n_name, *name_tmp = NULL;
long namelen, n_namelen, i, error;
unsigned long mod_user_size;
struct module_ref *dep;
if (!capable(CAP_SYS_MODULE))
return -EPERM;
lock_kernel();
if ((namelen = get_mod_name(name_user, &name)) < 0) {
error = namelen;
goto err0;
}
if ((mod = find_module(name)) == NULL) {
error = -ENOENT;
goto err1;
}
/* Check module header size. We allow a bit of slop over the
size we are familiar with to cope with a version of insmod
for a newer kernel. But don't over do it. */
if ((error = get_user(mod_user_size, &mod_user->size_of_struct)) != 0)
goto err1;
if (mod_user_size < (unsigned long)&((struct module *)0L)->persist_start
|| mod_user_size > sizeof(struct module) + 16*sizeof(void*)) {
printk(KERN_ERR "init_module: Invalid module header size.\n"
KERN_ERR "A new version of the modutils is likely "
"needed.\n");
error = -EINVAL;
goto err1;
}
/* Hold the current contents while we play with the user's idea
of righteousness. */
mod_tmp = *mod;
name_tmp = kmalloc(strlen(mod->name) + 1, GFP_KERNEL); /* Where's kstrdup()? */
if (name_tmp == NULL) {
error = -ENOMEM;
goto err1;
}
strcpy(name_tmp, mod->name);
error = copy_from_user(mod, mod_user, mod_user_size);
if (error) {
error = -EFAULT;
goto err2;
}
/* Sanity check the size of the module. */
error = -EINVAL;
if (mod->size > mod_tmp.size) {
printk(KERN_ERR "init_module: Size of initialized module "
"exceeds size of created module.\n");
goto err2;
}
/* Make sure all interesting pointers are sane. */
if (!mod_bound(mod->name, namelen, mod)) {
printk(KERN_ERR "init_module: mod->name out of bounds.\n");
goto err2;
}
if (mod->nsyms && !mod_bound(mod->syms, mod->nsyms, mod)) {
printk(KERN_ERR "init_module: mod->syms out of bounds.\n");
goto err2;
}
if (mod->ndeps && !mod_bound(mod->deps, mod->ndeps, mod)) {
printk(KERN_ERR "init_module: mod->deps out of bounds.\n");
goto err2;
}
if (mod->init && !mod_bound(mod->init, 0, mod)) {
printk(KERN_ERR "init_module: mod->init out of bounds.\n");
goto err2;
}
if (mod->cleanup && !mod_bound(mod->cleanup, 0, mod)) {
printk(KERN_ERR "init_module: mod->cleanup out of bounds.\n");
goto err2;
}
if (mod->ex_table_start > mod->ex_table_end
|| (mod->ex_table_start &&
!((unsigned long)mod->ex_table_start >= ((unsigned long)mod + mod->size_of_struct)
&& ((unsigned long)mod->ex_table_end
< (unsigned long)mod + mod->size)))
|| (((unsigned long)mod->ex_table_start
- (unsigned long)mod->ex_table_end)
% sizeof(struct exception_table_entry))) {
printk(KERN_ERR "init_module: mod->ex_table_* invalid.\n");
goto err2;
}
if (mod->flags & ~MOD_AUTOCLEAN) {
printk(KERN_ERR "init_module: mod->flags invalid.\n");
goto err2;
}
if (mod_member_present(mod, can_unload)
&& mod->can_unload && !mod_bound(mod->can_unload, 0, mod)) {
printk(KERN_ERR "init_module: mod->can_unload out of bounds.\n");
goto err2;
}
if (mod_member_present(mod, kallsyms_end)) {
if (mod->kallsyms_end &&
(!mod_bound(mod->kallsyms_start, 0, mod) ||
!mod_bound(mod->kallsyms_end, 0, mod))) {
printk(KERN_ERR "init_module: mod->kallsyms out of bounds.\n");
goto err2;
}
if (mod->kallsyms_start > mod->kallsyms_end) {
printk(KERN_ERR "init_module: mod->kallsyms invalid.\n");
goto err2;
}
}
if (mod_member_present(mod, archdata_end)) {
if (mod->archdata_end &&
(!mod_bound(mod->archdata_start, 0, mod) ||
!mod_bound(mod->archdata_end, 0, mod))) {
printk(KERN_ERR "init_module: mod->archdata out of bounds.\n");
goto err2;
}
if (mod->archdata_start > mod->archdata_end) {
printk(KERN_ERR "init_module: mod->archdata invalid.\n");
goto err2;
}
}
if (mod_member_present(mod, kernel_data) && mod->kernel_data) {
printk(KERN_ERR "init_module: mod->kernel_data must be zero.\n");
goto err2;
}
/* Check that the user isn't doing something silly with the name. */
if ((n_namelen = get_mod_name(mod->name - (unsigned long)mod
+ (unsigned long)mod_user,
&n_name)) < 0) {
printk(KERN_ERR "init_module: get_mod_name failure.\n");
error = n_namelen;
goto err2;
}
if (namelen != n_namelen || strcmp(n_name, mod_tmp.name) != 0) {
printk(KERN_ERR "init_module: changed module name to "
"`%s' from `%s'\n",
n_name, mod_tmp.name);
goto err3;
}
/* Ok, that's about all the sanity we can stomach; copy the rest. */
if (copy_from_user((char *)mod+mod_user_size,
(char *)mod_user+mod_user_size,
mod->size-mod_user_size)) {
error = -EFAULT;
goto err3;
}
if (module_arch_init(mod))
goto err3;
/* On some machines it is necessary to do something here
to make the I and D caches consistent. */
flush_icache_range((unsigned long)mod, (unsigned long)mod + mod->size);
mod->next = mod_tmp.next;
mod->refs = NULL;
/* Sanity check the module's dependents */
for (i = 0, dep = mod->deps; i < mod->ndeps; ++i, ++dep) {
struct module *o, *d = dep->dep;
/* Make sure the indicated dependencies are really modules. */
if (d == mod) {
printk(KERN_ERR "init_module: self-referential "
"dependency in mod->deps.\n");
goto err3;
}
/* Scan the current modules for this dependency */
for (o = module_list; o != &kernel_module && o != d; o = o->next)
;
if (o != d) {
printk(KERN_ERR "init_module: found dependency that is "
"(no longer?) a module.\n");
goto err3;
}
}
/* Update module references. */
for (i = 0, dep = mod->deps; i < mod->ndeps; ++i, ++dep) {
struct module *d = dep->dep;
dep->ref = mod;
dep->next_ref = d->refs;
d->refs = dep;
/* Being referenced by a dependent module counts as a
use as far as kmod is concerned. */
d->flags |= MOD_USED_ONCE;
}
/* Free our temporary memory. */
put_mod_name(n_name);
put_mod_name(name);
/* Initialize the module. */
atomic_set(&mod->uc.usecount,1);
mod->flags |= MOD_INITIALIZING;
if (mod->init && (error = mod->init()) != 0) {
atomic_set(&mod->uc.usecount,0);
mod->flags &= ~MOD_INITIALIZING;
if (error > 0) /* Buggy module */
error = -EBUSY;
goto err0;
}
atomic_dec(&mod->uc.usecount);
/* And set it running. */
mod->flags = (mod->flags | MOD_RUNNING) & ~MOD_INITIALIZING;
error = 0;
goto err0;
err3:
put_mod_name(n_name);
err2:
*mod = mod_tmp;
strcpy((char *)mod->name, name_tmp); /* We know there is room for this */
err1:
put_mod_name(name);
err0:
unlock_kernel();
kfree(name_tmp);
return error;
}
static spinlock_t unload_lock = SPIN_LOCK_UNLOCKED;
int try_inc_mod_count(struct module *mod)
{
int res = 1;
if (mod) {
spin_lock(&unload_lock);
if (mod->flags & MOD_DELETED)
res = 0;
else
__MOD_INC_USE_COUNT(mod);
spin_unlock(&unload_lock);
}
return res;
}
asmlinkage long
sys_delete_module(const char *name_user)
{
struct module *mod, *next;
char *name;
long error;
int something_changed;
if (!capable(CAP_SYS_MODULE))
return -EPERM;
lock_kernel();
if (name_user) {
if ((error = get_mod_name(name_user, &name)) < 0)
goto out;
error = -ENOENT;
if ((mod = find_module(name)) == NULL) {
put_mod_name(name);
goto out;
}
put_mod_name(name);
error = -EBUSY;
if (mod->refs != NULL)
goto out;
spin_lock(&unload_lock);
if (!__MOD_IN_USE(mod)) {
mod->flags |= MOD_DELETED;
spin_unlock(&unload_lock);
free_module(mod, 0);
error = 0;
} else {
spin_unlock(&unload_lock);
}
goto out;
}
/* Do automatic reaping */
restart:
something_changed = 0;
for (mod = module_list; mod != &kernel_module; mod = next) {
next = mod->next;
spin_lock(&unload_lock);
if (mod->refs == NULL
&& (mod->flags & MOD_AUTOCLEAN)
&& (mod->flags & MOD_RUNNING)
&& !(mod->flags & MOD_DELETED)
&& (mod->flags & MOD_USED_ONCE)
&& !__MOD_IN_USE(mod)) {
if ((mod->flags & MOD_VISITED)
&& !(mod->flags & MOD_JUST_FREED)) {
spin_unlock(&unload_lock);
mod->flags &= ~MOD_VISITED;
} else {
mod->flags |= MOD_DELETED;
spin_unlock(&unload_lock);
free_module(mod, 1);
something_changed = 1;
}
} else {
spin_unlock(&unload_lock);
}
}
if (something_changed)
goto restart;
for (mod = module_list; mod != &kernel_module; mod = mod->next)
mod->flags &= ~MOD_JUST_FREED;
error = 0;
out:
unlock_kernel();
return error;
}
/* Query various bits about modules. */
static int
qm_modules(char *buf, size_t bufsize, size_t *ret)
{
struct module *mod;
size_t nmod, space, len;
nmod = space = 0;
for (mod=module_list; mod != &kernel_module; mod=mod->next, ++nmod) {
len = strlen(mod->name)+1;
if (len > bufsize)
goto calc_space_needed;
if (copy_to_user(buf, mod->name, len))
return -EFAULT;
buf += len;
bufsize -= len;
space += len;
}
if (put_user(nmod, ret))
return -EFAULT;
else
return 0;
calc_space_needed:
space += len;
while ((mod = mod->next) != &kernel_module)
space += strlen(mod->name)+1;
if (put_user(space, ret))
return -EFAULT;
else
return -ENOSPC;
}
static int
qm_deps(struct module *mod, char *buf, size_t bufsize, size_t *ret)
{
size_t i, space, len;
if (mod == &kernel_module)
return -EINVAL;
if (!MOD_CAN_QUERY(mod))
if (put_user(0, ret))
return -EFAULT;
else
return 0;
space = 0;
for (i = 0; i < mod->ndeps; ++i) {
const char *dep_name = mod->deps[i].dep->name;
len = strlen(dep_name)+1;
if (len > bufsize)
goto calc_space_needed;
if (copy_to_user(buf, dep_name, len))
return -EFAULT;
buf += len;
bufsize -= len;
space += len;
}
if (put_user(i, ret))
return -EFAULT;
else
return 0;
calc_space_needed:
space += len;
while (++i < mod->ndeps)
space += strlen(mod->deps[i].dep->name)+1;
if (put_user(space, ret))
return -EFAULT;
else
return -ENOSPC;
}
static int
qm_refs(struct module *mod, char *buf, size_t bufsize, size_t *ret)
{
size_t nrefs, space, len;
struct module_ref *ref;
if (mod == &kernel_module)
return -EINVAL;
if (!MOD_CAN_QUERY(mod))
if (put_user(0, ret))
return -EFAULT;
else
return 0;
space = 0;
for (nrefs = 0, ref = mod->refs; ref ; ++nrefs, ref = ref->next_ref) {
const char *ref_name = ref->ref->name;
len = strlen(ref_name)+1;
if (len > bufsize)
goto calc_space_needed;
if (copy_to_user(buf, ref_name, len))
return -EFAULT;
buf += len;
bufsize -= len;
space += len;
}
if (put_user(nrefs, ret))
return -EFAULT;
else
return 0;
calc_space_needed:
space += len;
while ((ref = ref->next_ref) != NULL)
space += strlen(ref->ref->name)+1;
if (put_user(space, ret))
return -EFAULT;
else
return -ENOSPC;
}
static int
qm_symbols(struct module *mod, char *buf, size_t bufsize, size_t *ret)
{
size_t i, space, len;
struct module_symbol *s;
char *strings;
unsigned long *vals;
if (!MOD_CAN_QUERY(mod))
if (put_user(0, ret))
return -EFAULT;
else
return 0;
space = mod->nsyms * 2*sizeof(void *);
i = len = 0;
s = mod->syms;
if (space > bufsize)
goto calc_space_needed;
if (!access_ok(VERIFY_WRITE, buf, space))
return -EFAULT;
bufsize -= space;
vals = (unsigned long *)buf;
strings = buf+space;
for (; i < mod->nsyms ; ++i, ++s, vals += 2) {
len = strlen(s->name)+1;
if (len > bufsize)
goto calc_space_needed;
if (copy_to_user(strings, s->name, len)
|| __put_user(s->value, vals+0)
|| __put_user(space, vals+1))
return -EFAULT;
strings += len;
bufsize -= len;
space += len;
}
if (put_user(i, ret))
return -EFAULT;
else
return 0;
calc_space_needed:
for (; i < mod->nsyms; ++i, ++s)
space += strlen(s->name)+1;
if (put_user(space, ret))
return -EFAULT;
else
return -ENOSPC;
}
static int
qm_info(struct module *mod, char *buf, size_t bufsize, size_t *ret)
{
int error = 0;
if (mod == &kernel_module)
return -EINVAL;
if (sizeof(struct module_info) <= bufsize) {
struct module_info info;
info.addr = (unsigned long)mod;
info.size = mod->size;
info.flags = mod->flags;
/* usecount is one too high here - report appropriately to
compensate for locking */
info.usecount = (mod_member_present(mod, can_unload)
&& mod->can_unload ? -1 : atomic_read(&mod->uc.usecount)-1);
if (copy_to_user(buf, &info, sizeof(struct module_info)))
return -EFAULT;
} else
error = -ENOSPC;
if (put_user(sizeof(struct module_info), ret))
return -EFAULT;
return error;
}
asmlinkage long
sys_query_module(const char *name_user, int which, char *buf, size_t bufsize,
size_t *ret)
{
struct module *mod;
int err;
lock_kernel();
if (name_user == NULL)
mod = &kernel_module;
else {
long namelen;
char *name;
if ((namelen = get_mod_name(name_user, &name)) < 0) {
err = namelen;
goto out;
}
err = -ENOENT;
if ((mod = find_module(name)) == NULL) {
put_mod_name(name);
goto out;
}
put_mod_name(name);
}
/* __MOD_ touches the flags. We must avoid that */
atomic_inc(&mod->uc.usecount);
switch (which)
{
case 0:
err = 0;
break;
case QM_MODULES:
err = qm_modules(buf, bufsize, ret);
break;
case QM_DEPS:
err = qm_deps(mod, buf, bufsize, ret);
break;
case QM_REFS:
err = qm_refs(mod, buf, bufsize, ret);
break;
case QM_SYMBOLS:
err = qm_symbols(mod, buf, bufsize, ret);
break;
case QM_INFO:
err = qm_info(mod, buf, bufsize, ret);
break;
default:
err = -EINVAL;
break;
}
atomic_dec(&mod->uc.usecount);
out:
unlock_kernel();
return err;
}
/*
* Copy the kernel symbol table to user space. If the argument is
* NULL, just return the size of the table.
*
* This call is obsolete. New programs should use query_module+QM_SYMBOLS
* which does not arbitrarily limit the length of symbols.
*/
asmlinkage long
sys_get_kernel_syms(struct kernel_sym *table)
{
struct module *mod;
int i;
struct kernel_sym ksym;
lock_kernel();
for (mod = module_list, i = 0; mod; mod = mod->next) {
/* include the count for the module name! */
i += mod->nsyms + 1;
}
if (table == NULL)
goto out;
/* So that we don't give the user our stack content */
memset (&ksym, 0, sizeof (ksym));
for (mod = module_list, i = 0; mod; mod = mod->next) {
struct module_symbol *msym;
unsigned int j;
if (!MOD_CAN_QUERY(mod))
continue;
/* magic: write module info as a pseudo symbol */
ksym.value = (unsigned long)mod;
ksym.name[0] = '#';
strncpy(ksym.name+1, mod->name, sizeof(ksym.name)-1);
ksym.name[sizeof(ksym.name)-1] = '\0';
if (copy_to_user(table, &ksym, sizeof(ksym)) != 0)
goto out;
++i, ++table;
if (mod->nsyms == 0)
continue;
for (j = 0, msym = mod->syms; j < mod->nsyms; ++j, ++msym) {
ksym.value = msym->value;
strncpy(ksym.name, msym->name, sizeof(ksym.name));
ksym.name[sizeof(ksym.name)-1] = '\0';
if (copy_to_user(table, &ksym, sizeof(ksym)) != 0)
goto out;
++i, ++table;
}
}
out:
unlock_kernel();
return i;
}
/*
* Look for a module by name, ignoring modules marked for deletion.
*/
struct module *
find_module(const char *name)
{
struct module *mod;
for (mod = module_list; mod ; mod = mod->next) {
if (mod->flags & MOD_DELETED)
continue;
if (!strcmp(mod->name, name))
break;
}
return mod;
}
/*
* Free the given module.
*/
void
free_module(struct module *mod, int tag_freed)
{
struct module_ref *dep;
unsigned i;
unsigned long flags;
/* Let the module clean up. */
if (mod->flags & MOD_RUNNING)
{
if(mod->cleanup)
mod->cleanup();
mod->flags &= ~MOD_RUNNING;
}
/* Remove the module from the dependency lists. */
for (i = 0, dep = mod->deps; i < mod->ndeps; ++i, ++dep) {
struct module_ref **pp;
for (pp = &dep->dep->refs; *pp != dep; pp = &(*pp)->next_ref)
continue;
*pp = dep->next_ref;
if (tag_freed && dep->dep->refs == NULL)
dep->dep->flags |= MOD_JUST_FREED;
}
/* And from the main module list. */
spin_lock_irqsave(&modlist_lock, flags);
if (mod == module_list) {
module_list = mod->next;
} else {
struct module *p;
for (p = module_list; p->next != mod; p = p->next)
continue;
p->next = mod->next;
}
spin_unlock_irqrestore(&modlist_lock, flags);
/* And free the memory. */
module_unmap(mod);
}
/*
* Called by the /proc file system to return a current list of modules.
*/
int get_module_list(char *p)
{
size_t left = PAGE_SIZE;
struct module *mod;
char tmpstr[64];
struct module_ref *ref;
for (mod = module_list; mod != &kernel_module; mod = mod->next) {
long len;
const char *q;
#define safe_copy_str(str, len) \
do { \
if (left < len) \
goto fini; \
memcpy(p, str, len); p += len, left -= len; \
} while (0)
#define safe_copy_cstr(str) safe_copy_str(str, sizeof(str)-1)
len = strlen(mod->name);
safe_copy_str(mod->name, len);
if ((len = 20 - len) > 0) {
if (left < len)
goto fini;
memset(p, ' ', len);
p += len;
left -= len;
}
len = sprintf(tmpstr, "%8lu", mod->size);
safe_copy_str(tmpstr, len);
if (mod->flags & MOD_RUNNING) {
len = sprintf(tmpstr, "%4ld",
(mod_member_present(mod, can_unload)
&& mod->can_unload
? -1L : (long)atomic_read(&mod->uc.usecount)));
safe_copy_str(tmpstr, len);
}
if (mod->flags & MOD_DELETED)
safe_copy_cstr(" (deleted)");
else if (mod->flags & MOD_RUNNING) {
if (mod->flags & MOD_AUTOCLEAN)
safe_copy_cstr(" (autoclean)");
if (!(mod->flags & MOD_USED_ONCE))
safe_copy_cstr(" (unused)");
}
else if (mod->flags & MOD_INITIALIZING)
safe_copy_cstr(" (initializing)");
else
safe_copy_cstr(" (uninitialized)");
if ((ref = mod->refs) != NULL) {
safe_copy_cstr(" [");
while (1) {
q = ref->ref->name;
len = strlen(q);
safe_copy_str(q, len);
if ((ref = ref->next_ref) != NULL)
safe_copy_cstr(" ");
else
break;
}
safe_copy_cstr("]");
}
safe_copy_cstr("\n");
#undef safe_copy_str
#undef safe_copy_cstr
}
fini:
return PAGE_SIZE - left;
}
/*
* Called by the /proc file system to return a current list of ksyms.
*/
struct mod_sym {
struct module *mod;
int index;
};
/* iterator */
static void *s_start(struct seq_file *m, loff_t *pos)
{
struct mod_sym *p = kmalloc(sizeof(*p), GFP_KERNEL);
struct module *v;
loff_t n = *pos;
if (!p)
return ERR_PTR(-ENOMEM);
lock_kernel();
for (v = module_list, n = *pos; v; n -= v->nsyms, v = v->next) {
if (n < v->nsyms) {
p->mod = v;
p->index = n;
return p;
}
}
unlock_kernel();
kfree(p);
return NULL;
}
static void *s_next(struct seq_file *m, void *p, loff_t *pos)
{
struct mod_sym *v = p;
(*pos)++;
if (++v->index >= v->mod->nsyms) {
do {
v->mod = v->mod->next;
if (!v->mod) {
unlock_kernel();
kfree(p);
return NULL;
}
} while (!v->mod->nsyms);
v->index = 0;
}
return p;
}
static void s_stop(struct seq_file *m, void *p)
{
if (p && !IS_ERR(p)) {
unlock_kernel();
kfree(p);
}
}
static int s_show(struct seq_file *m, void *p)
{
struct mod_sym *v = p;
struct module_symbol *sym;
if (!MOD_CAN_QUERY(v->mod))
return 0;
sym = &v->mod->syms[v->index];
if (*v->mod->name)
seq_printf(m, "%0*lx %s\t[%s]\n", (int)(2*sizeof(void*)),
sym->value, sym->name, v->mod->name);
else
seq_printf(m, "%0*lx %s\n", (int)(2*sizeof(void*)),
sym->value, sym->name);
return 0;
}
struct seq_operations ksyms_op = {
start: s_start,
next: s_next,
stop: s_stop,
show: s_show
};
#else /* CONFIG_MODULES */
/* Dummy syscalls for people who don't want modules */
asmlinkage unsigned long
sys_create_module(const char *name_user, size_t size)
{
return -ENOSYS;
}
asmlinkage long
sys_init_module(const char *name_user, struct module *mod_user)
{
return -ENOSYS;
}
asmlinkage long
sys_delete_module(const char *name_user)
{
return -ENOSYS;
}
asmlinkage long
sys_query_module(const char *name_user, int which, char *buf, size_t bufsize,
size_t *ret)
{
/* Let the program know about the new interface. Not that
it'll do them much good. */
if (which == 0)
return 0;
return -ENOSYS;
}
asmlinkage long
sys_get_kernel_syms(struct kernel_sym *table)
{
return -ENOSYS;
}
int try_inc_mod_count(struct module *mod)
{
return 1;
}
#endif /* CONFIG_MODULES */
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