diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-18 12:06:57 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-07-18 12:06:57 -0700 |
commit | da0acd7c656c09b362b5095dc8595f8655dc1223 (patch) | |
tree | 6e4a3bba1abc52d3593345d8617e8c874a1b708c | |
parent | 818e95c768c6607a1df4cf022c00c3c58e2f203e (diff) | |
parent | 93651f80dcb616b8c9115cdafc8e57a781af22d0 (diff) |
Merge tag 'modules-for-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:
"Summary of modules changes for the 5.3 merge window:
- Code fixes and cleanups
- Fix bug where set_memory_x() wasn't being called when rodata=n
- Fix bug where -EEXIST was being returned for going modules
- Allow arches to override module_exit_section()"
* tag 'modules-for-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
modules: fix compile error if don't have strict module rwx
ARM: module: recognize unwind exit sections
module: allow arch overrides for .exit section names
modules: fix BUG when load module with rodata=n
kernel/module: Fix mem leak in module_add_modinfo_attrs
kernel: module: Use struct_size() helper
kernel/module.c: Only return -EEXIST for modules that have finished loading
-rw-r--r-- | arch/arm/kernel/module.c | 7 | ||||
-rw-r--r-- | include/linux/moduleloader.h | 5 | ||||
-rw-r--r-- | kernel/module.c | 60 |
3 files changed, 53 insertions, 19 deletions
diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c index b3d439c41c7b..deef17f34bd2 100644 --- a/arch/arm/kernel/module.c +++ b/arch/arm/kernel/module.c @@ -55,6 +55,13 @@ void *module_alloc(unsigned long size) } #endif +bool module_exit_section(const char *name) +{ + return strstarts(name, ".exit") || + strstarts(name, ".ARM.extab.exit") || + strstarts(name, ".ARM.exidx.exit"); +} + int apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex, unsigned int relindex, struct module *module) diff --git a/include/linux/moduleloader.h b/include/linux/moduleloader.h index 31013c2effd3..5229c18025e9 100644 --- a/include/linux/moduleloader.h +++ b/include/linux/moduleloader.h @@ -29,6 +29,11 @@ void *module_alloc(unsigned long size); /* Free memory returned from module_alloc. */ void module_memfree(void *module_region); +/* Determines if the section name is an exit section (that is only used during + * module unloading) + */ +bool module_exit_section(const char *name); + /* * Apply the given relocation to the (simplified) ELF. Return -error * or 0. diff --git a/kernel/module.c b/kernel/module.c index a2cee14a83f3..5933395af9a0 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1492,8 +1492,7 @@ static void add_sect_attrs(struct module *mod, const struct load_info *info) for (i = 0; i < info->hdr->e_shnum; i++) if (!sect_empty(&info->sechdrs[i])) nloaded++; - size[0] = ALIGN(sizeof(*sect_attrs) - + nloaded * sizeof(sect_attrs->attrs[0]), + size[0] = ALIGN(struct_size(sect_attrs, attrs, nloaded), sizeof(sect_attrs->grp.attrs[0])); size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]); sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL); @@ -1697,6 +1696,8 @@ static int add_usage_links(struct module *mod) return ret; } +static void module_remove_modinfo_attrs(struct module *mod, int end); + static int module_add_modinfo_attrs(struct module *mod) { struct module_attribute *attr; @@ -1711,24 +1712,34 @@ static int module_add_modinfo_attrs(struct module *mod) return -ENOMEM; temp_attr = mod->modinfo_attrs; - for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) { + for (i = 0; (attr = modinfo_attrs[i]); i++) { if (!attr->test || attr->test(mod)) { memcpy(temp_attr, attr, sizeof(*temp_attr)); sysfs_attr_init(&temp_attr->attr); error = sysfs_create_file(&mod->mkobj.kobj, &temp_attr->attr); + if (error) + goto error_out; ++temp_attr; } } + + return 0; + +error_out: + if (i > 0) + module_remove_modinfo_attrs(mod, --i); return error; } -static void module_remove_modinfo_attrs(struct module *mod) +static void module_remove_modinfo_attrs(struct module *mod, int end) { struct module_attribute *attr; int i; for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) { + if (end >= 0 && i > end) + break; /* pick a field to test for end of list */ if (!attr->attr.name) break; @@ -1816,7 +1827,7 @@ static int mod_sysfs_setup(struct module *mod, return 0; out_unreg_modinfo_attrs: - module_remove_modinfo_attrs(mod); + module_remove_modinfo_attrs(mod, -1); out_unreg_param: module_param_sysfs_remove(mod); out_unreg_holders: @@ -1852,7 +1863,7 @@ static void mod_sysfs_fini(struct module *mod) { } -static void module_remove_modinfo_attrs(struct module *mod) +static void module_remove_modinfo_attrs(struct module *mod, int end) { } @@ -1868,14 +1879,14 @@ static void init_param_lock(struct module *mod) static void mod_sysfs_teardown(struct module *mod) { del_usage_links(mod); - module_remove_modinfo_attrs(mod); + module_remove_modinfo_attrs(mod, -1); module_param_sysfs_remove(mod); kobject_put(mod->mkobj.drivers_dir); kobject_put(mod->holders_dir); mod_sysfs_fini(mod); } -#ifdef CONFIG_STRICT_MODULE_RWX +#ifdef CONFIG_ARCH_HAS_STRICT_MODULE_RWX /* * LKM RO/NX protection: protect module's text/ro-data * from modification and any data from execution. @@ -1898,6 +1909,7 @@ static void frob_text(const struct module_layout *layout, layout->text_size >> PAGE_SHIFT); } +#ifdef CONFIG_STRICT_MODULE_RWX static void frob_rodata(const struct module_layout *layout, int (*set_memory)(unsigned long start, int num_pages)) { @@ -1949,13 +1961,9 @@ void module_enable_ro(const struct module *mod, bool after_init) set_vm_flush_reset_perms(mod->core_layout.base); set_vm_flush_reset_perms(mod->init_layout.base); frob_text(&mod->core_layout, set_memory_ro); - frob_text(&mod->core_layout, set_memory_x); frob_rodata(&mod->core_layout, set_memory_ro); - frob_text(&mod->init_layout, set_memory_ro); - frob_text(&mod->init_layout, set_memory_x); - frob_rodata(&mod->init_layout, set_memory_ro); if (after_init) @@ -2014,9 +2022,19 @@ void set_all_modules_text_ro(void) } mutex_unlock(&module_mutex); } -#else +#else /* !CONFIG_STRICT_MODULE_RWX */ static void module_enable_nx(const struct module *mod) { } -#endif +#endif /* CONFIG_STRICT_MODULE_RWX */ +static void module_enable_x(const struct module *mod) +{ + frob_text(&mod->core_layout, set_memory_x); + frob_text(&mod->init_layout, set_memory_x); +} +#else /* !CONFIG_ARCH_HAS_STRICT_MODULE_RWX */ +static void module_enable_nx(const struct module *mod) { } +static void module_enable_x(const struct module *mod) { } +#endif /* CONFIG_ARCH_HAS_STRICT_MODULE_RWX */ + #ifdef CONFIG_LIVEPATCH /* @@ -2723,6 +2741,11 @@ void * __weak module_alloc(unsigned long size) return vmalloc_exec(size); } +bool __weak module_exit_section(const char *name) +{ + return strstarts(name, ".exit"); +} + #ifdef CONFIG_DEBUG_KMEMLEAK static void kmemleak_load_module(const struct module *mod, const struct load_info *info) @@ -2912,7 +2935,7 @@ static int rewrite_section_headers(struct load_info *info, int flags) #ifndef CONFIG_MODULE_UNLOAD /* Don't load .exit sections */ - if (strstarts(info->secstrings+shdr->sh_name, ".exit")) + if (module_exit_section(info->secstrings+shdr->sh_name)) shdr->sh_flags &= ~(unsigned long)SHF_ALLOC; #endif } @@ -3390,8 +3413,7 @@ static bool finished_loading(const char *name) sched_annotate_sleep(); mutex_lock(&module_mutex); mod = find_module_all(name, strlen(name), true); - ret = !mod || mod->state == MODULE_STATE_LIVE - || mod->state == MODULE_STATE_GOING; + ret = !mod || mod->state == MODULE_STATE_LIVE; mutex_unlock(&module_mutex); return ret; @@ -3581,8 +3603,7 @@ again: mutex_lock(&module_mutex); old = find_module_all(mod->name, strlen(mod->name), true); if (old != NULL) { - if (old->state == MODULE_STATE_COMING - || old->state == MODULE_STATE_UNFORMED) { + if (old->state != MODULE_STATE_LIVE) { /* Wait in case it fails to load. */ mutex_unlock(&module_mutex); err = wait_event_interruptible(module_wq, @@ -3621,6 +3642,7 @@ static int complete_formation(struct module *mod, struct load_info *info) module_enable_ro(mod, false); module_enable_nx(mod); + module_enable_x(mod); /* Mark state as coming so strong_try_module_get() ignores us, * but kallsyms etc. can see us. */ |