Le 09/02/2023 à 18:56, Song Liu a écrit : > Three changes here: > > 1. Shorter variable names in arch/arc/kernel/unwind.c:unwind_add_table, to > make it easier to read. > 2. Rewrite free_mod_mem() so it is more obvious that MOD_DATA need to be > freed last. > 3. Clean up the use of CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC. > > Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > Cc: Guenter Roeck <linux@xxxxxxxxxxxx> > Cc: Christophe Leroy <christophe.leroy@xxxxxxxxxx> > Signed-off-by: Song Liu <song@xxxxxxxxxx> > > --- > > This is the follow up patch on top of [1]. I would recommend fold this > into [1]. With this patch folded into [1], Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx> > > [1] https://lore.kernel.org/linux-modules/20230207002802.2514802-1-song@xxxxxxxxxx/T/#u > --- > arch/arc/kernel/unwind.c | 15 ++++------ > kernel/module/main.c | 61 +++++++++++----------------------------- > 2 files changed, 22 insertions(+), 54 deletions(-) > > diff --git a/arch/arc/kernel/unwind.c b/arch/arc/kernel/unwind.c > index 933451f4494f..9270d0a713c3 100644 > --- a/arch/arc/kernel/unwind.c > +++ b/arch/arc/kernel/unwind.c > @@ -369,8 +369,8 @@ void *unwind_add_table(struct module *module, const void *table_start, > unsigned long table_size) > { > struct unwind_table *table; > - struct module_memory *mod_mem_core_text; > - struct module_memory *mod_mem_init_text; > + struct module_memory *core_text; > + struct module_memory *init_text; > > if (table_size <= 0) > return NULL; > @@ -379,14 +379,11 @@ void *unwind_add_table(struct module *module, const void *table_start, > if (!table) > return NULL; > > - mod_mem_core_text = &module->mem[MOD_TEXT]; > - mod_mem_init_text = &module->mem[MOD_INIT_TEXT]; > + core_text = &module->mem[MOD_TEXT]; > + init_text = &module->mem[MOD_INIT_TEXT]; > > - init_unwind_table(table, module->name, > - mod_mem_core_text->base, mod_mem_core_text->size, > - mod_mem_init_text->base, mod_mem_init_text->size, > - table_start, table_size, > - NULL, 0); > + init_unwind_table(table, module->name, core_text->base, core_text->size, > + init_text->base, init_text->size, table_start, table_size, NULL, 0); > > init_unwind_hdr(table, unw_hdr_alloc); > > diff --git a/kernel/module/main.c b/kernel/module/main.c > index c598f11e7016..2724bc1b9a90 100644 > --- a/kernel/module/main.c > +++ b/kernel/module/main.c > @@ -927,26 +927,17 @@ static ssize_t store_uevent(struct module_attribute *mattr, > struct module_attribute module_uevent = > __ATTR(uevent, 0200, NULL, store_uevent); > > -#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC > - > -static ssize_t show_coresize(struct module_attribute *mattr, > - struct module_kobject *mk, char *buffer) > -{ > - return sprintf(buffer, "%u\n", mk->mod->mem[MOD_TEXT].size); > -} > - > -#else > - > static ssize_t show_coresize(struct module_attribute *mattr, > struct module_kobject *mk, char *buffer) > { > - unsigned int size = 0; > + unsigned int size = mk->mod->mem[MOD_TEXT].size; > > - for_class_mod_mem_type(type, core) > - size += mk->mod->mem[type].size; > + if (!IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC)) { > + for_class_mod_mem_type(type, core_data) > + size += mk->mod->mem[type].size; > + } > return sprintf(buffer, "%u\n", size); > } > -#endif > > static struct module_attribute modinfo_coresize = > __ATTR(coresize, 0444, show_coresize, NULL); > @@ -1170,17 +1161,11 @@ void __weak module_arch_freeing_init(struct module *mod) > { > } > > -#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC > static bool mod_mem_use_vmalloc(enum mod_mem_type type) > { > - return mod_mem_type_is_core_data(type); > -} > -#else > -static bool mod_mem_use_vmalloc(enum mod_mem_type type) > -{ > - return false; > + return IS_ENABLED(CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC) && > + mod_mem_type_is_core_data(type); > } > -#endif > > static void *module_memory_alloc(unsigned int size, enum mod_mem_type type) > { > @@ -1199,34 +1184,21 @@ static void module_memory_free(void *ptr, enum mod_mem_type type) > > static void free_mod_mem(struct module *mod) > { > - /* free the memory in the right order to avoid use-after-free */ > - static enum mod_mem_type mod_mem_free_order[MOD_MEM_NUM_TYPES] = { > - /* first free init sections */ > - MOD_INIT_TEXT, > - MOD_INIT_DATA, > - MOD_INIT_RODATA, > - > - /* then core sections, except rw data */ > - MOD_TEXT, > - MOD_RODATA, > - MOD_RO_AFTER_INIT, > - > - /* rw data need to be freed last, as it hosts mod */ > - MOD_DATA, > - }; > - int i; > - > - BUILD_BUG_ON(ARRAY_SIZE(mod_mem_free_order) != MOD_MEM_NUM_TYPES); > - > - for (i = 0; i < MOD_MEM_NUM_TYPES; i++) { > - enum mod_mem_type type = mod_mem_free_order[i]; > + for_each_mod_mem_type(type) { > struct module_memory *mod_mem = &mod->mem[type]; > > + if (type == MOD_DATA) > + continue; > + > /* Free lock-classes; relies on the preceding sync_rcu(). */ > lockdep_free_key_range(mod_mem->base, mod_mem->size); > if (mod_mem->size) > module_memory_free(mod_mem->base, type); > } > + > + /* MOD_DATA hosts mod, so free it at last */ > + lockdep_free_key_range(mod->mem[MOD_DATA].base, mod->mem[MOD_DATA].size); > + module_memory_free(mod->mem[MOD_DATA].base, MOD_DATA); > } > > /* Free a module, remove from lists, etc. */ > @@ -2211,8 +2183,7 @@ static int move_module(struct module *mod, struct load_info *info) > if (!(shdr->sh_flags & SHF_ALLOC)) > continue; > > - dest = mod->mem[type].base + > - (shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK); > + dest = mod->mem[type].base + (shdr->sh_entsize & SH_ENTSIZE_OFFSET_MASK); > > if (shdr->sh_type != SHT_NOBITS) > memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
