diff options
Diffstat (limited to 'kernel/module.c')
| -rw-r--r-- | kernel/module.c | 138 |
1 files changed, 79 insertions, 59 deletions
diff --git a/kernel/module.c b/kernel/module.c index 5432dbedf8cf..e2eec4b47143 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -46,7 +46,7 @@ #include <linux/string.h> #include <linux/mutex.h> #include <linux/rculist.h> -#include <asm/uaccess.h> +#include <linux/uaccess.h> #include <asm/cacheflush.h> #include <asm/mmu_context.h> #include <linux/license.h> @@ -314,8 +314,11 @@ struct load_info { } index; }; -/* We require a truly strong try_module_get(): 0 means failure due to - ongoing or failed initialization etc. */ +/* + * We require a truly strong try_module_get(): 0 means success. + * Otherwise an error is returned due to ongoing or failed + * initialization etc. + */ static inline int strong_try_module_get(struct module *mod) { BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED); @@ -331,7 +334,7 @@ static inline void add_taint_module(struct module *mod, unsigned flag, enum lockdep_ok lockdep_ok) { add_taint(flag, lockdep_ok); - mod->taints |= (1U << flag); + set_bit(flag, &mod->taints); } /* @@ -387,16 +390,16 @@ extern const struct kernel_symbol __start___ksymtab_gpl[]; extern const struct kernel_symbol __stop___ksymtab_gpl[]; extern const struct kernel_symbol __start___ksymtab_gpl_future[]; extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; -extern const unsigned long __start___kcrctab[]; -extern const unsigned long __start___kcrctab_gpl[]; -extern const unsigned long __start___kcrctab_gpl_future[]; +extern const s32 __start___kcrctab[]; +extern const s32 __start___kcrctab_gpl[]; +extern const s32 __start___kcrctab_gpl_future[]; #ifdef CONFIG_UNUSED_SYMBOLS extern const struct kernel_symbol __start___ksymtab_unused[]; extern const struct kernel_symbol __stop___ksymtab_unused[]; extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; -extern const unsigned long __start___kcrctab_unused[]; -extern const unsigned long __start___kcrctab_unused_gpl[]; +extern const s32 __start___kcrctab_unused[]; +extern const s32 __start___kcrctab_unused_gpl[]; #endif #ifndef CONFIG_MODVERSIONS @@ -495,7 +498,7 @@ struct find_symbol_arg { /* Output */ struct module *owner; - const unsigned long *crc; + const s32 *crc; const struct kernel_symbol *sym; }; @@ -561,7 +564,7 @@ static bool find_symbol_in_section(const struct symsearch *syms, * (optional) module which owns it. Needs preempt disabled or module_mutex. */ const struct kernel_symbol *find_symbol(const char *name, struct module **owner, - const unsigned long **crc, + const s32 **crc, bool gplok, bool warn) { @@ -1139,22 +1142,13 @@ static inline int module_unload_init(struct module *mod) static size_t module_flags_taint(struct module *mod, char *buf) { size_t l = 0; + int i; + + for (i = 0; i < TAINT_FLAGS_COUNT; i++) { + if (taint_flags[i].module && test_bit(i, &mod->taints)) + buf[l++] = taint_flags[i].c_true; + } - if (mod->taints & (1 << TAINT_PROPRIETARY_MODULE)) - buf[l++] = 'P'; - if (mod->taints & (1 << TAINT_OOT_MODULE)) - buf[l++] = 'O'; - if (mod->taints & (1 << TAINT_FORCED_MODULE)) - buf[l++] = 'F'; - if (mod->taints & (1 << TAINT_CRAP)) - buf[l++] = 'C'; - if (mod->taints & (1 << TAINT_UNSIGNED_MODULE)) - buf[l++] = 'E'; - /* - * TAINT_FORCED_RMMOD: could be added. - * TAINT_CPU_OUT_OF_SPEC, TAINT_MACHINE_CHECK, TAINT_BAD_PAGE don't - * apply to modules. - */ return l; } @@ -1256,23 +1250,17 @@ static int try_to_force_load(struct module *mod, const char *reason) } #ifdef CONFIG_MODVERSIONS -/* If the arch applies (non-zero) relocations to kernel kcrctab, unapply it. */ -static unsigned long maybe_relocated(unsigned long crc, - const struct module *crc_owner) + +static u32 resolve_rel_crc(const s32 *crc) { -#ifdef ARCH_RELOCATES_KCRCTAB - if (crc_owner == NULL) - return crc - (unsigned long)reloc_start; -#endif - return crc; + return *(u32 *)((void *)crc + *crc); } static int check_version(Elf_Shdr *sechdrs, unsigned int versindex, const char *symname, struct module *mod, - const unsigned long *crc, - const struct module *crc_owner) + const s32 *crc) { unsigned int i, num_versions; struct modversion_info *versions; @@ -1290,18 +1278,25 @@ static int check_version(Elf_Shdr *sechdrs, / sizeof(struct modversion_info); for (i = 0; i < num_versions; i++) { + u32 crcval; + if (strcmp(versions[i].name, symname) != 0) continue; - if (versions[i].crc == maybe_relocated(*crc, crc_owner)) + if (IS_ENABLED(CONFIG_MODULE_REL_CRCS)) + crcval = resolve_rel_crc(crc); + else + crcval = *crc; + if (versions[i].crc == crcval) return 1; - pr_debug("Found checksum %lX vs module %lX\n", - maybe_relocated(*crc, crc_owner), versions[i].crc); + pr_debug("Found checksum %X vs module %lX\n", + crcval, versions[i].crc); goto bad_version; } - pr_warn("%s: no symbol version for %s\n", mod->name, symname); - return 0; + /* Broken toolchain. Warn once, then let it go.. */ + pr_warn_once("%s: no symbol version for %s\n", mod->name, symname); + return 1; bad_version: pr_warn("%s: disagrees about version of symbol %s\n", @@ -1313,7 +1308,7 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs, unsigned int versindex, struct module *mod) { - const unsigned long *crc; + const s32 *crc; /* * Since this should be found in kernel (which can't be removed), no @@ -1327,8 +1322,7 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs, } preempt_enable(); return check_version(sechdrs, versindex, - VMLINUX_SYMBOL_STR(module_layout), mod, crc, - NULL); + VMLINUX_SYMBOL_STR(module_layout), mod, crc); } /* First part is kernel version, which we ignore if module has crcs. */ @@ -1346,8 +1340,7 @@ static inline int check_version(Elf_Shdr *sechdrs, unsigned int versindex, const char *symname, struct module *mod, - const unsigned long *crc, - const struct module *crc_owner) + const s32 *crc) { return 1; } @@ -1374,7 +1367,7 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod, { struct module *owner; const struct kernel_symbol *sym; - const unsigned long *crc; + const s32 *crc; int err; /* @@ -1389,8 +1382,7 @@ static const struct kernel_symbol *resolve_symbol(struct module *mod, if (!sym) goto unlock; - if (!check_version(info->sechdrs, info->index.vers, name, mod, crc, - owner)) { + if (!check_version(info->sechdrs, info->index.vers, name, mod, crc)) { sym = ERR_PTR(-EINVAL); goto getname; } @@ -1909,6 +1901,9 @@ static void frob_writable_data(const struct module_layout *layout, /* livepatching wants to disable read-only so it can frob module. */ void module_disable_ro(const struct module *mod) { + if (!rodata_enabled) + return; + frob_text(&mod->core_layout, set_memory_rw); frob_rodata(&mod->core_layout, set_memory_rw); frob_ro_after_init(&mod->core_layout, set_memory_rw); @@ -1918,6 +1913,9 @@ void module_disable_ro(const struct module *mod) void module_enable_ro(const struct module *mod, bool after_init) { + if (!rodata_enabled) + return; + frob_text(&mod->core_layout, set_memory_ro); frob_rodata(&mod->core_layout, set_memory_ro); frob_text(&mod->init_layout, set_memory_ro); @@ -1950,6 +1948,9 @@ void set_all_modules_text_rw(void) { struct module *mod; + if (!rodata_enabled) + return; + mutex_lock(&module_mutex); list_for_each_entry_rcu(mod, &modules, list) { if (mod->state == MODULE_STATE_UNFORMED) @@ -1966,9 +1967,18 @@ void set_all_modules_text_ro(void) { struct module *mod; + if (!rodata_enabled) + return; + mutex_lock(&module_mutex); list_for_each_entry_rcu(mod, &modules, list) { - if (mod->state == MODULE_STATE_UNFORMED) + /* + * Ignore going modules since it's possible that ro + * protection has already been disabled, otherwise we'll + * run into protection faults at module deallocation. + */ + if (mod->state == MODULE_STATE_UNFORMED || + mod->state == MODULE_STATE_GOING) continue; frob_text(&mod->core_layout, set_memory_ro); @@ -1979,10 +1989,12 @@ void set_all_modules_text_ro(void) static void disable_ro_nx(const struct module_layout *layout) { - frob_text(layout, set_memory_rw); - frob_rodata(layout, set_memory_rw); + if (rodata_enabled) { + frob_text(layout, set_memory_rw); + frob_rodata(layout, set_memory_rw); + frob_ro_after_init(layout, set_memory_rw); + } frob_rodata(layout, set_memory_x); - frob_ro_after_init(layout, set_memory_rw); frob_ro_after_init(layout, set_memory_x); frob_writable_data(layout, set_memory_x); } @@ -2793,14 +2805,17 @@ static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned l } #ifdef CONFIG_LIVEPATCH -static int find_livepatch_modinfo(struct module *mod, struct load_info *info) +static int check_modinfo_livepatch(struct module *mod, struct load_info *info) { - mod->klp = get_modinfo(info, "livepatch") ? true : false; + if (get_modinfo(info, "livepatch")) { + mod->klp = true; + add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK); + } return 0; } #else /* !CONFIG_LIVEPATCH */ -static int find_livepatch_modinfo(struct module *mod, struct load_info *info) +static int check_modinfo_livepatch(struct module *mod, struct load_info *info) { if (get_modinfo(info, "livepatch")) { pr_err("%s: module is marked as livepatch module, but livepatch support is disabled", @@ -2970,7 +2985,7 @@ static int check_modinfo(struct module *mod, struct load_info *info, int flags) "is unknown, you have been warned.\n", mod->name); } - err = find_livepatch_modinfo(mod, info); + err = check_modinfo_livepatch(mod, info); if (err) return err; @@ -3706,6 +3721,7 @@ static int load_module(struct load_info *info, const char __user *uargs, sysfs_cleanup: mod_sysfs_teardown(mod); coming_cleanup: + mod->state = MODULE_STATE_GOING; blocking_notifier_call_chain(&module_notify_list, MODULE_STATE_GOING, mod); klp_module_going(mod); @@ -4039,6 +4055,10 @@ int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *, } #endif /* CONFIG_KALLSYMS */ +/* Maximum number of characters written by module_flags() */ +#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) + +/* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */ static char *module_flags(struct module *mod, char *buf) { int bx = 0; @@ -4083,7 +4103,7 @@ static void m_stop(struct seq_file *m, void *p) static int m_show(struct seq_file *m, void *p) { struct module *mod = list_entry(p, struct module, list); - char buf[8]; + char buf[MODULE_FLAGS_BUF_SIZE]; /* We always ignore unformed modules. */ if (mod->state == MODULE_STATE_UNFORMED) @@ -4254,7 +4274,7 @@ EXPORT_SYMBOL_GPL(__module_text_address); void print_modules(void) { struct module *mod; - char buf[8]; + char buf[MODULE_FLAGS_BUF_SIZE]; printk(KERN_DEFAULT "Modules linked in:"); /* Most callers should already have preempt disabled, but make sure */ |