diff options
| -rw-r--r-- | kernel/module.c | 246 |
1 files changed, 125 insertions, 121 deletions
diff --git a/kernel/module.c b/kernel/module.c index 031bf26..679e4c8 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -164,131 +164,140 @@ static const struct kernel_symbol *lookup_symbol(const char *name, 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, " - "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"); + return true; } -/* 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) +static bool printk_unused_warning(bool gplok, bool warn, const char *name) { - struct module *mod; - const struct kernel_symbol *ks; - - /* Core kernel first. */ - *owner = NULL; - ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab); - if (ks) { - *crc = symversion(__start___kcrctab, (ks - __start___ksymtab)); - return ks->value; + if (warn) { + 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"); } - if (gplok) { - ks = lookup_symbol(name, __start___ksymtab_gpl, - __stop___ksymtab_gpl); - if (ks) { - *crc = symversion(__start___kcrctab_gpl, - (ks - __start___ksymtab_gpl)); - return ks->value; - } - } - 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; + return true; +} + +static bool gpl_only_unused_warning(bool gplok, bool warn, const char *name) +{ + if (!gplok) + return false; + return printk_unused_warning(gplok, warn, name); +} + +static bool gpl_only(bool gplok, bool warn, const char *name) +{ + return gplok; +} + +static bool warn_if_not_gpl(bool gplok, bool warn, const char *name) +{ + if (!gplok && warn) { + 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"); } + return true; +} - 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; +struct symsearch { + const struct kernel_symbol *start, *stop; + const unsigned long *crcs; + bool (*check)(bool gplok, bool warn, const char *name); +}; + +/* 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; +} - if (gplok) - ks = lookup_symbol(name, __start___ksymtab_unused_gpl, - __stop___ksymtab_unused_gpl); +/* 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 }, + }; + + /* Core kernel first. */ + ks = search_symarrays(arr, ARRAY_SIZE(arr), name, gplok, warn, crc); if (ks) { - printk_unused_warning(name); - *crc = symversion(__start___kcrctab_unused_gpl, - (ks - __start___ksymtab_unused_gpl)); + if (owner) + *owner = NULL; return ks->value; } /* Now try modules. */ list_for_each_entry(mod, &modules, list) { - *owner = mod; - ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms); + struct symsearch arr[] = { + { mod->syms, mod->syms + mod->num_syms, mod->crcs, + always_ok }, + { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms, + mod->gpl_crcs, gpl_only }, + { mod->gpl_future_syms, + mod->gpl_future_syms + mod->num_gpl_future_syms, + mod->gpl_future_crcs, warn_if_not_gpl }, + { mod->unused_syms, + mod->unused_syms + mod->num_unused_syms, + mod->unused_crcs, printk_unused_warning }, + { mod->unused_gpl_syms, + mod->unused_gpl_syms + mod->num_unused_gpl_syms, + mod->unused_gpl_crcs, gpl_only_unused_warning }, + }; + + ks = search_symarrays(arr, ARRAY_SIZE(arr), + name, gplok, warn, crc); if (ks) { - *crc = symversion(mod->crcs, (ks - mod->syms)); - return ks->value; - } - - if (gplok) { - 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; - } - } - 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; - } - } - 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)); + if (owner) + *owner = mod; return ks->value; } } + DEBUGP("Failed to find symbol %s\n", name); return -ENOENT; } @@ -777,10 +786,9 @@ static void print_unload_info(struct seq_file *m, struct module *mod) void __symbol_put(const char *symbol) { struct module *owner; - const unsigned long *crc; preempt_disable(); - if (IS_ERR_VALUE(__find_symbol(symbol, &owner, &crc, 1))) + if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false))) BUG(); module_put(owner); preempt_enable(); @@ -924,13 +932,10 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs, struct module *mod) { const unsigned long *crc; - struct module *owner; - if (IS_ERR_VALUE(__find_symbol("struct_module", - &owner, &crc, 1))) + if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false))) BUG(); - return check_version(sechdrs, versindex, "struct_module", mod, - crc); + return check_version(sechdrs, versindex, "struct_module", mod, crc); } /* First part is kernel version, which we ignore. */ @@ -974,8 +979,8 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs, unsigned long ret; const unsigned long *crc; - ret = __find_symbol(name, &owner, &crc, - !(mod->taints & TAINT_PROPRIETARY_MODULE)); + ret = find_symbol(name, &owner, &crc, + !(mod->taints & TAINT_PROPRIETARY_MODULE), true); if (!IS_ERR_VALUE(ret)) { /* use_module can fail due to OOM, or module initialization or unloading */ @@ -1376,10 +1381,9 @@ void *__symbol_get(const char *symbol) { struct module *owner; unsigned long value; - const unsigned long *crc; preempt_disable(); - value = __find_symbol(symbol, &owner, &crc, 1); + value = find_symbol(symbol, &owner, NULL, true, true); if (IS_ERR_VALUE(value)) value = 0; else if (strong_try_module_get(owner)) @@ -1402,16 +1406,16 @@ static int verify_export_symbols(struct module *mod) const unsigned long *crc; for (i = 0; i < mod->num_syms; i++) - if (!IS_ERR_VALUE(__find_symbol(mod->syms[i].name, - &owner, &crc, 1))) { + if (!IS_ERR_VALUE(find_symbol(mod->syms[i].name, + &owner, &crc, true, false))) { name = mod->syms[i].name; ret = -ENOEXEC; goto dup; } for (i = 0; i < mod->num_gpl_syms; i++) - if (!IS_ERR_VALUE(__find_symbol(mod->gpl_syms[i].name, - &owner, &crc, 1))) { + if (!IS_ERR_VALUE(find_symbol(mod->gpl_syms[i].name, + &owner, &crc, true, false))) { name = mod->gpl_syms[i].name; ret = -ENOEXEC; goto dup; |
