Commit 03fc922f authored by Linus Torvalds's avatar Linus Torvalds

Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus

* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  module: add MODULE_STATE_GOING notifier call
  module: Enhance verify_export_symbols
  module: set unused_gpl_crcs instead of overwriting unused_crcs
  module: neaten __find_symbol, rename to find_symbol
  module: reduce module image and resident size
  module: make module_sect_attrs private to kernel/module.c
parents a0be7522 df4b565e
...@@ -190,7 +190,7 @@ void *__symbol_get_gpl(const char *symbol); ...@@ -190,7 +190,7 @@ void *__symbol_get_gpl(const char *symbol);
extern typeof(sym) sym; \ extern typeof(sym) sym; \
__CRC_SYMBOL(sym, sec) \ __CRC_SYMBOL(sym, sec) \
static const char __kstrtab_##sym[] \ static const char __kstrtab_##sym[] \
__attribute__((section("__ksymtab_strings"))) \ __attribute__((section("__ksymtab_strings"), aligned(1))) \
= MODULE_SYMBOL_PREFIX #sym; \ = MODULE_SYMBOL_PREFIX #sym; \
static const struct kernel_symbol __ksymtab_##sym \ static const struct kernel_symbol __ksymtab_##sym \
__used \ __used \
...@@ -229,23 +229,6 @@ enum module_state ...@@ -229,23 +229,6 @@ enum module_state
MODULE_STATE_GOING, MODULE_STATE_GOING,
}; };
/* Similar stuff for section attributes. */
struct module_sect_attr
{
struct module_attribute mattr;
char *name;
unsigned long address;
};
struct module_sect_attrs
{
struct attribute_group grp;
int nsections;
struct module_sect_attr attrs[0];
};
struct module_param_attrs;
struct module struct module
{ {
enum module_state state; enum module_state state;
......
...@@ -164,131 +164,140 @@ static const struct kernel_symbol *lookup_symbol(const char *name, ...@@ -164,131 +164,140 @@ static const struct kernel_symbol *lookup_symbol(const char *name,
return NULL; return NULL;
} }
static void printk_unused_warning(const char *name) static bool always_ok(bool gplok, bool warn, const char *name)
{ {
printk(KERN_WARNING "Symbol %s is marked as UNUSED, " return true;
"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");
} }
/* Find a symbol, return value, crc and module which owns it */ static bool printk_unused_warning(bool gplok, bool warn, const char *name)
static unsigned long __find_symbol(const char *name,
struct module **owner,
const unsigned long **crc,
int gplok)
{ {
struct module *mod; if (warn) {
const struct kernel_symbol *ks; printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
"however this module is using it.\n", name);
/* Core kernel first. */ printk(KERN_WARNING
*owner = NULL; "This symbol will go away in the future.\n");
ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab); printk(KERN_WARNING
if (ks) { "Please evalute if this is the right api to use and if "
*crc = symversion(__start___kcrctab, (ks - __start___ksymtab)); "it really is, submit a report the linux kernel "
return ks->value; "mailinglist together with submitting your code for "
"inclusion.\n");
} }
if (gplok) { return true;
ks = lookup_symbol(name, __start___ksymtab_gpl, }
__stop___ksymtab_gpl);
if (ks) { static bool gpl_only_unused_warning(bool gplok, bool warn, const char *name)
*crc = symversion(__start___kcrctab_gpl, {
(ks - __start___ksymtab_gpl)); if (!gplok)
return ks->value; return false;
} return printk_unused_warning(gplok, warn, name);
} }
ks = lookup_symbol(name, __start___ksymtab_gpl_future,
__stop___ksymtab_gpl_future); static bool gpl_only(bool gplok, bool warn, const char *name)
if (ks) { {
if (!gplok) { return gplok;
printk(KERN_WARNING "Symbol %s is being used " }
"by a non-GPL module, which will not "
"be allowed in the future\n", name); static bool warn_if_not_gpl(bool gplok, bool warn, const char *name)
printk(KERN_WARNING "Please see the file " {
"Documentation/feature-removal-schedule.txt " if (!gplok && warn) {
"in the kernel source tree for more " printk(KERN_WARNING "Symbol %s is being used "
"details.\n"); "by a non-GPL module, which will not "
} "be allowed in the future\n", name);
*crc = symversion(__start___kcrctab_gpl_future, printk(KERN_WARNING "Please see the file "
(ks - __start___ksymtab_gpl_future)); "Documentation/feature-removal-schedule.txt "
return ks->value; "in the kernel source tree for more details.\n");
} }
return true;
}
ks = lookup_symbol(name, __start___ksymtab_unused, struct symsearch {
__stop___ksymtab_unused); const struct kernel_symbol *start, *stop;
if (ks) { const unsigned long *crcs;
printk_unused_warning(name); bool (*check)(bool gplok, bool warn, const char *name);
*crc = symversion(__start___kcrctab_unused, };
(ks - __start___ksymtab_unused));
return ks->value; /* Look through this array of symbol tables for a symbol match which
* passes the check function. */
static const struct kernel_symbol *search_symarrays(const struct symsearch *arr,
unsigned int num,
const char *name,
bool gplok,
bool warn,
const unsigned long **crc)
{
unsigned int i;
const struct kernel_symbol *ks;
for (i = 0; i < num; i++) {
ks = lookup_symbol(name, arr[i].start, arr[i].stop);
if (!ks || !arr[i].check(gplok, warn, name))
continue;
if (crc)
*crc = symversion(arr[i].crcs, ks - arr[i].start);
return ks;
} }
return NULL;
}
/* Find a symbol, return value, (optional) crc and (optional) module
* which owns it */
static unsigned long find_symbol(const char *name,
struct module **owner,
const unsigned long **crc,
bool gplok,
bool warn)
{
struct module *mod;
const struct kernel_symbol *ks;
const struct symsearch arr[] = {
{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
always_ok },
{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
__start___kcrctab_gpl, gpl_only },
{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
__start___kcrctab_gpl_future, warn_if_not_gpl },
{ __start___ksymtab_unused, __stop___ksymtab_unused,
__start___kcrctab_unused, printk_unused_warning },
{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
__start___kcrctab_unused_gpl, gpl_only_unused_warning },
};
if (gplok) /* Core kernel first. */
ks = lookup_symbol(name, __start___ksymtab_unused_gpl, ks = search_symarrays(arr, ARRAY_SIZE(arr), name, gplok, warn, crc);
__stop___ksymtab_unused_gpl);
if (ks) { if (ks) {
printk_unused_warning(name); if (owner)
*crc = symversion(__start___kcrctab_unused_gpl, *owner = NULL;
(ks - __start___ksymtab_unused_gpl));
return ks->value; return ks->value;
} }
/* Now try modules. */ /* Now try modules. */
list_for_each_entry(mod, &modules, list) { list_for_each_entry(mod, &modules, list) {
*owner = mod; struct symsearch arr[] = {
ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms); { mod->syms, mod->syms + mod->num_syms, mod->crcs,
if (ks) { always_ok },
*crc = symversion(mod->crcs, (ks - mod->syms)); { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
return ks->value; mod->gpl_crcs, gpl_only },
} { mod->gpl_future_syms,
mod->gpl_future_syms + mod->num_gpl_future_syms,
if (gplok) { mod->gpl_future_crcs, warn_if_not_gpl },
ks = lookup_symbol(name, mod->gpl_syms, { mod->unused_syms,
mod->gpl_syms + mod->num_gpl_syms); mod->unused_syms + mod->num_unused_syms,
if (ks) { mod->unused_crcs, printk_unused_warning },
*crc = symversion(mod->gpl_crcs, { mod->unused_gpl_syms,
(ks - mod->gpl_syms)); mod->unused_gpl_syms + mod->num_unused_gpl_syms,
return ks->value; mod->unused_gpl_crcs, gpl_only_unused_warning },
} };
}
ks = lookup_symbol(name, mod->unused_syms, mod->unused_syms + mod->num_unused_syms); ks = search_symarrays(arr, ARRAY_SIZE(arr),
name, gplok, warn, crc);
if (ks) { if (ks) {
printk_unused_warning(name); if (owner)
*crc = symversion(mod->unused_crcs, (ks - mod->unused_syms)); *owner = mod;
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;
}
}
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; return ks->value;
} }
} }
DEBUGP("Failed to find symbol %s\n", name); DEBUGP("Failed to find symbol %s\n", name);
return -ENOENT; return -ENOENT;
} }
...@@ -736,12 +745,13 @@ sys_delete_module(const char __user *name_user, unsigned int flags) ...@@ -736,12 +745,13 @@ sys_delete_module(const char __user *name_user, unsigned int flags)
if (!forced && module_refcount(mod) != 0) if (!forced && module_refcount(mod) != 0)
wait_for_zero_refcount(mod); wait_for_zero_refcount(mod);
mutex_unlock(&module_mutex);
/* Final destruction now noone is using it. */ /* Final destruction now noone is using it. */
if (mod->exit != NULL) { if (mod->exit != NULL)
mutex_unlock(&module_mutex);
mod->exit(); mod->exit();
mutex_lock(&module_mutex); blocking_notifier_call_chain(&module_notify_list,
} MODULE_STATE_GOING, mod);
mutex_lock(&module_mutex);
/* Store the name of the last unloaded module for diagnostic purposes */ /* Store the name of the last unloaded module for diagnostic purposes */
strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module)); strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
free_module(mod); free_module(mod);
...@@ -777,10 +787,9 @@ static void print_unload_info(struct seq_file *m, struct module *mod) ...@@ -777,10 +787,9 @@ static void print_unload_info(struct seq_file *m, struct module *mod)
void __symbol_put(const char *symbol) void __symbol_put(const char *symbol)
{ {
struct module *owner; struct module *owner;
const unsigned long *crc;
preempt_disable(); preempt_disable();
if (IS_ERR_VALUE(__find_symbol(symbol, &owner, &crc, 1))) if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false)))
BUG(); BUG();
module_put(owner); module_put(owner);
preempt_enable(); preempt_enable();
...@@ -924,13 +933,10 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs, ...@@ -924,13 +933,10 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs,
struct module *mod) struct module *mod)
{ {
const unsigned long *crc; const unsigned long *crc;
struct module *owner;
if (IS_ERR_VALUE(__find_symbol("struct_module", if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false)))
&owner, &crc, 1)))
BUG(); BUG();
return check_version(sechdrs, versindex, "struct_module", mod, return check_version(sechdrs, versindex, "struct_module", mod, crc);
crc);
} }
/* First part is kernel version, which we ignore. */ /* First part is kernel version, which we ignore. */
...@@ -974,8 +980,8 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs, ...@@ -974,8 +980,8 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
unsigned long ret; unsigned long ret;
const unsigned long *crc; const unsigned long *crc;
ret = __find_symbol(name, &owner, &crc, ret = find_symbol(name, &owner, &crc,
!(mod->taints & TAINT_PROPRIETARY_MODULE)); !(mod->taints & TAINT_PROPRIETARY_MODULE), true);
if (!IS_ERR_VALUE(ret)) { if (!IS_ERR_VALUE(ret)) {
/* use_module can fail due to OOM, /* use_module can fail due to OOM,
or module initialization or unloading */ or module initialization or unloading */
...@@ -991,6 +997,20 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs, ...@@ -991,6 +997,20 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
* J. Corbet <corbet@lwn.net> * J. Corbet <corbet@lwn.net>
*/ */
#if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS) #if defined(CONFIG_KALLSYMS) && defined(CONFIG_SYSFS)
struct module_sect_attr
{
struct module_attribute mattr;
char *name;
unsigned long address;
};
struct module_sect_attrs
{
struct attribute_group grp;
unsigned int nsections;
struct module_sect_attr attrs[0];
};
static ssize_t module_sect_show(struct module_attribute *mattr, static ssize_t module_sect_show(struct module_attribute *mattr,
struct module *mod, char *buf) struct module *mod, char *buf)
{ {
...@@ -1001,7 +1021,7 @@ static ssize_t module_sect_show(struct module_attribute *mattr, ...@@ -1001,7 +1021,7 @@ static ssize_t module_sect_show(struct module_attribute *mattr,
static void free_sect_attrs(struct module_sect_attrs *sect_attrs) static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
{ {
int section; unsigned int section;
for (section = 0; section < sect_attrs->nsections; section++) for (section = 0; section < sect_attrs->nsections; section++)
kfree(sect_attrs->attrs[section].name); kfree(sect_attrs->attrs[section].name);
...@@ -1362,10 +1382,9 @@ void *__symbol_get(const char *symbol) ...@@ -1362,10 +1382,9 @@ void *__symbol_get(const char *symbol)
{ {
struct module *owner; struct module *owner;
unsigned long value; unsigned long value;
const unsigned long *crc;
preempt_disable(); preempt_disable();
value = __find_symbol(symbol, &owner, &crc, 1); value = find_symbol(symbol, &owner, NULL, true, true);
if (IS_ERR_VALUE(value)) if (IS_ERR_VALUE(value))
value = 0; value = 0;
else if (strong_try_module_get(owner)) else if (strong_try_module_get(owner))
...@@ -1382,33 +1401,33 @@ EXPORT_SYMBOL_GPL(__symbol_get); ...@@ -1382,33 +1401,33 @@ EXPORT_SYMBOL_GPL(__symbol_get);
*/ */
static int verify_export_symbols(struct module *mod) static int verify_export_symbols(struct module *mod)
{ {
const char *name = NULL; unsigned int i;
unsigned long i, ret = 0;
struct module *owner; struct module *owner;
const unsigned long *crc; const struct kernel_symbol *s;
struct {
for (i = 0; i < mod->num_syms; i++) const struct kernel_symbol *sym;
if (!IS_ERR_VALUE(__find_symbol(mod->syms[i].name, unsigned int num;
&owner, &crc, 1))) { } arr[] = {
name = mod->syms[i].name; { mod->syms, mod->num_syms },
ret = -ENOEXEC; { mod->gpl_syms, mod->num_gpl_syms },
goto dup; { mod->gpl_future_syms, mod->num_gpl_future_syms },
} { mod->unused_syms, mod->num_unused_syms },
{ mod->unused_gpl_syms, mod->num_unused_gpl_syms },
};
for (i = 0; i < mod->num_gpl_syms; i++) for (i = 0; i < ARRAY_SIZE(arr); i++) {
if (!IS_ERR_VALUE(__find_symbol(mod->gpl_syms[i].name, for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
&owner, &crc, 1))) { if (!IS_ERR_VALUE(find_symbol(s->name, &owner,
name = mod->gpl_syms[i].name; NULL, true, false))) {
ret = -ENOEXEC; printk(KERN_ERR
goto dup; "%s: exports duplicate symbol %s"
" (owned by %s)\n",
mod->name, s->name, module_name(owner));
return -ENOEXEC;
}
} }
}
dup: return 0;
if (ret)
printk(KERN_ERR "%s: exports duplicate symbol %s (owned by %s)\n",
mod->name, name, module_name(owner));
return ret;
} }
/* Change all symbols so that st_value encodes the pointer directly. */ /* Change all symbols so that st_value encodes the pointer directly. */
...@@ -1814,8 +1833,9 @@ static struct module *load_module(void __user *umod, ...@@ -1814,8 +1833,9 @@ static struct module *load_module(void __user *umod,
unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME); unwindex = find_sec(hdr, sechdrs, secstrings, ARCH_UNWIND_SECTION_NAME);
#endif #endif
/* Don't keep modinfo section */ /* Don't keep modinfo and version sections. */
sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC; sechdrs[infoindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
sechdrs[versindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
#ifdef CONFIG_KALLSYMS #ifdef CONFIG_KALLSYMS
/* Keep symbol and string tables for decoding later. */ /* Keep symbol and string tables for decoding later. */
sechdrs[symindex].sh_flags |= SHF_ALLOC; sechdrs[symindex].sh_flags |= SHF_ALLOC;
...@@ -1977,7 +1997,8 @@ static struct module *load_module(void __user *umod, ...@@ -1977,7 +1997,8 @@ static struct module *load_module(void __user *umod,
mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr; mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr;
mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr; mod->unused_gpl_syms = (void *)sechdrs[unusedgplindex].sh_addr;
if (unusedgplcrcindex) if (unusedgplcrcindex)
mod->unused_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr; mod->unused_gpl_crcs
= (void *)sechdrs[unusedgplcrcindex].sh_addr;
#ifdef CONFIG_MODVERSIONS #ifdef CONFIG_MODVERSIONS
if ((mod->num_syms && !crcindex) || if ((mod->num_syms && !crcindex) ||
...@@ -2171,6 +2192,8 @@ sys_init_module(void __user *umod, ...@@ -2171,6 +2192,8 @@ sys_init_module(void __user *umod,
mod->state = MODULE_STATE_GOING; mod->state = MODULE_STATE_GOING;
synchronize_sched(); synchronize_sched();
module_put(mod); module_put(mod);
blocking_notifier_call_chain(&module_notify_list,
MODULE_STATE_GOING, mod);
mutex_lock(&module_mutex); mutex_lock(&module_mutex);
free_module(mod); free_module(mod);
mutex_unlock(&module_mutex); mutex_unlock(&module_mutex);
......
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