From patchwork Wed Feb 23 12:02:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christophe Leroy X-Patchwork-Id: 12756849 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 49BC7C4167E for ; Wed, 23 Feb 2022 12:03:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240356AbiBWMDb (ORCPT ); Wed, 23 Feb 2022 07:03:31 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35568 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240315AbiBWMD2 (ORCPT ); Wed, 23 Feb 2022 07:03:28 -0500 Received: from pegase2.c-s.fr (pegase2.c-s.fr [93.17.235.10]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D49789BADF; Wed, 23 Feb 2022 04:02:53 -0800 (PST) Received: from localhost (mailhub3.si.c-s.fr [172.26.127.67]) by localhost (Postfix) with ESMTP id 4K3ZRK30bWz9sSq; Wed, 23 Feb 2022 13:02:37 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from pegase2.c-s.fr ([172.26.127.65]) by localhost (pegase2.c-s.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id MIdAyq5rmbFq; Wed, 23 Feb 2022 13:02:37 +0100 (CET) Received: from messagerie.si.c-s.fr (messagerie.si.c-s.fr [192.168.25.192]) by pegase2.c-s.fr (Postfix) with ESMTP id 4K3ZRC2bzsz9sSr; Wed, 23 Feb 2022 13:02:31 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by messagerie.si.c-s.fr (Postfix) with ESMTP id 4A4ED8B77A; Wed, 23 Feb 2022 13:02:31 +0100 (CET) X-Virus-Scanned: amavisd-new at c-s.fr Received: from messagerie.si.c-s.fr ([127.0.0.1]) by localhost (messagerie.si.c-s.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id G6uKEhDENLLF; Wed, 23 Feb 2022 13:02:31 +0100 (CET) Received: from PO20335.IDSI0.si.c-s.fr (unknown [192.168.7.201]) by messagerie.si.c-s.fr (Postfix) with ESMTP id C74BB8B77D; Wed, 23 Feb 2022 13:02:30 +0100 (CET) Received: from PO20335.IDSI0.si.c-s.fr (localhost [127.0.0.1]) by PO20335.IDSI0.si.c-s.fr (8.17.1/8.16.1) with ESMTPS id 21NC2Mgv1148195 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Wed, 23 Feb 2022 13:02:22 +0100 Received: (from chleroy@localhost) by PO20335.IDSI0.si.c-s.fr (8.17.1/8.17.1/Submit) id 21NC2LQE1148194; Wed, 23 Feb 2022 13:02:21 +0100 X-Authentication-Warning: PO20335.IDSI0.si.c-s.fr: chleroy set sender to christophe.leroy@csgroup.eu using -f From: Christophe Leroy To: Luis Chamberlain , Aaron Tomlin Cc: Christophe Leroy , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kgdb-bugreport@lists.sourceforge.net, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-modules@vger.kernel.org, Jason Wessel , Daniel Thompson , Douglas Anderson Subject: [PATCH v6 4/6] module: Add CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC Date: Wed, 23 Feb 2022 13:02:14 +0100 Message-Id: X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1645617734; l=10818; s=20211009; h=from:subject:message-id; bh=ua4yghsJcnWod1SRFk39n4jnCVKFwyIXV5nTBerLwdc=; b=nN3xjrxme7kxD3xtne2y9rzZth1BJKyJZZIRRUsjW6T+cDPownfKvnrG04Odwz37nIaocSyzhY+C leSRMfTiCjhhaT69HSjY5wJeOYbmQTSs/Zo8WZ8X/FKvUVu7bDcf X-Developer-Key: i=christophe.leroy@csgroup.eu; a=ed25519; pk=HIzTzUj91asvincQGOFx6+ZF5AoUuP9GdOtQChs7Mm0= Precedence: bulk List-ID: Add CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC to allow architectures to request having modules data in vmalloc area instead of module area. This is required on powerpc book3s/32 in order to set data non executable, because it is not possible to set executability on page basis, this is done per 256 Mbytes segments. The module area has exec right, vmalloc area has noexec. This can also be useful on other powerpc/32 in order to maximize the chance of code being close enough to kernel core to avoid branch trampolines. Cc: Jason Wessel Acked-by: Daniel Thompson Cc: Douglas Anderson Signed-off-by: Christophe Leroy --- arch/Kconfig | 6 ++++ include/linux/module.h | 8 +++++ kernel/debug/kdb/kdb_main.c | 10 +++++-- kernel/module/internal.h | 3 ++ kernel/module/main.c | 58 +++++++++++++++++++++++++++++++++++-- kernel/module/procfs.c | 8 +++-- kernel/module/strict_rwx.c | 1 + kernel/module/tree_lookup.c | 8 +++++ 8 files changed, 96 insertions(+), 6 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 678a80713b21..b5d1f2c19c27 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -882,6 +882,12 @@ config MODULES_USE_ELF_REL Modules only use ELF REL relocations. Modules with ELF RELA relocations will give an error. +config ARCH_WANTS_MODULES_DATA_IN_VMALLOC + bool + help + For architectures like powerpc/32 which have constraints on module + allocation and need to allocate module data outside of module area. + config HAVE_IRQ_EXIT_ON_IRQ_STACK bool help diff --git a/include/linux/module.h b/include/linux/module.h index 7ec9715de7dc..134c1df04b14 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -422,6 +422,9 @@ struct module { /* Core layout: rbtree is accessed frequently, so keep together. */ struct module_layout core_layout __module_layout_align; struct module_layout init_layout; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + struct module_layout data_layout; +#endif /* Arch-specific module values */ struct mod_arch_specific arch; @@ -569,6 +572,11 @@ bool is_module_text_address(unsigned long addr); static inline bool within_module_core(unsigned long addr, const struct module *mod) { +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + if ((unsigned long)mod->data_layout.base <= addr && + addr < (unsigned long)mod->data_layout.base + mod->data_layout.size) + return true; +#endif return (unsigned long)mod->core_layout.base <= addr && addr < (unsigned long)mod->core_layout.base + mod->core_layout.size; } diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index 5369bf45c5d4..94de2889a062 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -2027,8 +2027,11 @@ static int kdb_lsmod(int argc, const char **argv) if (mod->state == MODULE_STATE_UNFORMED) continue; - kdb_printf("%-20s%8u 0x%px ", mod->name, - mod->core_layout.size, (void *)mod); + kdb_printf("%-20s%8u", mod->name, mod->core_layout.size); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + kdb_printf("/%8u", mod->data_layout.size); +#endif + kdb_printf(" 0x%px ", (void *)mod); #ifdef CONFIG_MODULE_UNLOAD kdb_printf("%4d ", module_refcount(mod)); #endif @@ -2039,6 +2042,9 @@ static int kdb_lsmod(int argc, const char **argv) else kdb_printf(" (Live)"); kdb_printf(" 0x%px", mod->core_layout.base); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + kdb_printf("/0x%px", mod->data_layout.base); +#endif #ifdef CONFIG_MODULE_UNLOAD { diff --git a/kernel/module/internal.h b/kernel/module/internal.h index 0aabbf5cbcd1..3e23bef5884d 100644 --- a/kernel/module/internal.h +++ b/kernel/module/internal.h @@ -20,7 +20,9 @@ /* Maximum number of characters written by module_flags() */ #define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4) +#ifndef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC #define data_layout core_layout +#endif /* * Modules' sections will be aligned on page boundaries @@ -154,6 +156,7 @@ struct mod_tree_root { }; extern struct mod_tree_root mod_tree; +extern struct mod_tree_root mod_data_tree; #ifdef CONFIG_MODULES_TREE_LOOKUP void mod_tree_insert(struct module *mod); diff --git a/kernel/module/main.c b/kernel/module/main.c index 84db7318ba2b..cf236e964cf6 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -78,6 +78,12 @@ struct mod_tree_root mod_tree __cacheline_aligned = { .addr_min = -1UL, }; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC +struct mod_tree_root mod_data_tree __cacheline_aligned = { + .addr_min = -1UL, +}; +#endif + #define module_addr_min mod_tree.addr_min #define module_addr_max mod_tree.addr_max @@ -107,6 +113,9 @@ static void mod_update_bounds(struct module *mod) __mod_update_bounds(mod->core_layout.base, mod->core_layout.size, &mod_tree); if (mod->init_layout.size) __mod_update_bounds(mod->init_layout.base, mod->init_layout.size, &mod_tree); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + __mod_update_bounds(mod->data_layout.base, mod->data_layout.size, &mod_data_tree); +#endif } static void module_assert_mutex_or_preempt(void) @@ -940,6 +949,17 @@ static ssize_t show_coresize(struct module_attribute *mattr, static struct module_attribute modinfo_coresize = __ATTR(coresize, 0444, show_coresize, NULL); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC +static ssize_t show_datasize(struct module_attribute *mattr, + struct module_kobject *mk, char *buffer) +{ + return sprintf(buffer, "%u\n", mk->mod->data_layout.size); +} + +static struct module_attribute modinfo_datasize = + __ATTR(datasize, 0444, show_datasize, NULL); +#endif + static ssize_t show_initsize(struct module_attribute *mattr, struct module_kobject *mk, char *buffer) { @@ -968,6 +988,9 @@ struct module_attribute *modinfo_attrs[] = { &modinfo_srcversion, &modinfo_initstate, &modinfo_coresize, +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + &modinfo_datasize, +#endif &modinfo_initsize, &modinfo_taint, #ifdef CONFIG_MODULE_UNLOAD @@ -1194,6 +1217,9 @@ static void free_module(struct module *mod) /* Finally, free the core (containing the module structure) */ module_memfree(mod->core_layout.base); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + vfree(mod->data_layout.base); +#endif } void *__symbol_get(const char *symbol) @@ -2124,6 +2150,24 @@ static int move_module(struct module *mod, struct load_info *info) } else mod->init_layout.base = NULL; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + /* Do the allocs. */ + ptr = vmalloc(mod->data_layout.size); + /* + * The pointer to this block is stored in the module structure + * which is inside the block. Just mark it as not being a + * leak. + */ + kmemleak_not_leak(ptr); + if (!ptr) { + module_memfree(mod->core_layout.base); + module_memfree(mod->init_layout.base); + return -ENOMEM; + } + + memset(ptr, 0, mod->data_layout.size); + mod->data_layout.base = ptr; +#endif /* Transfer each section which specifies SHF_ALLOC */ pr_debug("final section addresses:\n"); for (i = 0; i < info->hdr->e_shnum; i++) { @@ -2299,6 +2343,9 @@ static void module_deallocate(struct module *mod, struct load_info *info) module_arch_freeing_init(mod); module_memfree(mod->init_layout.base); module_memfree(mod->core_layout.base); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + vfree(mod->data_layout.base); +#endif } int __weak module_finalize(const Elf_Ehdr *hdr, @@ -3015,13 +3062,20 @@ bool is_module_address(unsigned long addr) struct module *__module_address(unsigned long addr) { struct module *mod; + struct mod_tree_root *tree; - if (addr < module_addr_min || addr > module_addr_max) + if (addr >= mod_tree.addr_min && addr <= mod_tree.addr_max) + tree = &mod_tree; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + else if (addr >= mod_data_tree.addr_min && addr <= mod_data_tree.addr_max) + tree = &mod_data_tree; +#endif + else return NULL; module_assert_mutex_or_preempt(); - mod = mod_find(addr, &mod_tree); + mod = mod_find(addr, tree); if (mod) { BUG_ON(!within_module(addr, mod)); if (mod->state == MODULE_STATE_UNFORMED) diff --git a/kernel/module/procfs.c b/kernel/module/procfs.c index 2717e130788e..9a8f4f0f6329 100644 --- a/kernel/module/procfs.c +++ b/kernel/module/procfs.c @@ -67,13 +67,17 @@ static int m_show(struct seq_file *m, void *p) struct module *mod = list_entry(p, struct module, list); char buf[MODULE_FLAGS_BUF_SIZE]; void *value; + unsigned int size; /* We always ignore unformed modules. */ if (mod->state == MODULE_STATE_UNFORMED) return 0; - seq_printf(m, "%s %u", - mod->name, mod->init_layout.size + mod->core_layout.size); + size = mod->init_layout.size + mod->core_layout.size; +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + size += mod->data_layout.size; +#endif + seq_printf(m, "%s %u", mod->name, size); print_unload_info(m, mod); /* Informative for users. */ diff --git a/kernel/module/strict_rwx.c b/kernel/module/strict_rwx.c index fe3c10891407..14fbea66f12f 100644 --- a/kernel/module/strict_rwx.c +++ b/kernel/module/strict_rwx.c @@ -75,6 +75,7 @@ bool module_check_misalignment(const struct module *mod) return false; return layout_check_misalignment(&mod->core_layout) || + layout_check_misalignment(&mod->data_layout) || layout_check_misalignment(&mod->init_layout); } diff --git a/kernel/module/tree_lookup.c b/kernel/module/tree_lookup.c index 995fe68059db..8ec5cfd60496 100644 --- a/kernel/module/tree_lookup.c +++ b/kernel/module/tree_lookup.c @@ -83,6 +83,11 @@ void mod_tree_insert(struct module *mod) __mod_tree_insert(&mod->core_layout.mtn, &mod_tree); if (mod->init_layout.size) __mod_tree_insert(&mod->init_layout.mtn, &mod_tree); + +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + mod->data_layout.mtn.mod = mod; + __mod_tree_insert(&mod->data_layout.mtn, &mod_data_tree); +#endif } void mod_tree_remove_init(struct module *mod) @@ -95,6 +100,9 @@ void mod_tree_remove(struct module *mod) { __mod_tree_remove(&mod->core_layout.mtn, &mod_tree); mod_tree_remove_init(mod); +#ifdef CONFIG_ARCH_WANTS_MODULES_DATA_IN_VMALLOC + __mod_tree_remove(&mod->data_layout.mtn, &mod_data_tree); +#endif } struct module *mod_find(unsigned long addr, struct mod_tree_root *tree)