From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02D94C433F5 for ; Sun, 2 Sep 2018 09:48:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B1F1820837 for ; Sun, 2 Sep 2018 09:48:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B1F1820837 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727169AbeIBOC5 (ORCPT ); Sun, 2 Sep 2018 10:02:57 -0400 Received: from mga07.intel.com ([134.134.136.100]:58896 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726006AbeIBOC5 (ORCPT ); Sun, 2 Sep 2018 10:02:57 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Sep 2018 02:47:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.53,319,1531810800"; d="scan'208";a="69718292" Received: from sai-dev-mach.sc.intel.com ([143.183.140.52]) by orsmga007.jf.intel.com with ESMTP; 02 Sep 2018 02:47:46 -0700 From: Sai Praneeth Prakhya To: linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: ricardo.neri@intel.com, matt@codeblueprint.co.uk, Sai Praneeth , Lee Chun-Yi , Al Stone , Borislav Petkov , Ingo Molnar , Andy Lutomirski , Bhupesh Sharma , Peter Zijlstra , Ard Biesheuvel Subject: [PATCH V2 2/6] x86/efi: Remove __init attribute from memory mapping functions Date: Sun, 2 Sep 2018 02:46:30 -0700 Message-Id: <1535881594-25469-3-git-send-email-sai.praneeth.prakhya@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1535881594-25469-1-git-send-email-sai.praneeth.prakhya@intel.com> References: <1535881594-25469-1-git-send-email-sai.praneeth.prakhya@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sai Praneeth Buggy firmware could illegally access EFI_BOOT_SERVICES_CODE/DATA regions even after the kernel has assumed control of the platform. When "CONFIG_EFI_WARN_ON_ILLEGAL_ACCESS" is enabled, the efi page fault handler will detect/fixup these illegal accesses. The below modified functions are used by the page fault handler to fixup illegal accesses to EFI_BOOT_SERVICES_CODE/DATA regions. As the page fault handler is present during/after kernel boot it doesn't have an __init attribute, but the below functions have it and thus during kernel build, "WARNING: modpost: Found * section mismatch(es)" build warning is observed. To fix it, remove __init attribute for all these functions. In order to not keep these functions needlessly when "CONFIG_EFI_WARN_ON_ILLEGAL_ACCESS" is not selected, add a new __efi_init_fixup attribute whose value changes based on whether the config option is selected or not. Suggested-by: Matt Fleming Based-on-code-from: Ricardo Neri Signed-off-by: Sai Praneeth Prakhya Cc: Lee Chun-Yi Cc: Al Stone Cc: Borislav Petkov Cc: Ingo Molnar Cc: Andy Lutomirski Cc: Bhupesh Sharma Cc: Peter Zijlstra Cc: Ard Biesheuvel --- arch/x86/include/asm/efi.h | 11 ++++++----- arch/x86/platform/efi/efi.c | 4 ++-- arch/x86/platform/efi/efi_32.c | 2 +- arch/x86/platform/efi/efi_64.c | 9 +++++---- drivers/firmware/efi/efi.c | 6 +++--- include/linux/efi.h | 16 ++++++++++++++-- 6 files changed, 31 insertions(+), 17 deletions(-) diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h index cec5fae23eb3..9b70743400f3 100644 --- a/arch/x86/include/asm/efi.h +++ b/arch/x86/include/asm/efi.h @@ -103,8 +103,9 @@ struct efi_scratch { preempt_enable(); \ }) -extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size, - u32 type, u64 attribute); +extern void __iomem *__efi_init_fixup efi_ioremap(unsigned long addr, + unsigned long size, u32 type, + u64 attribute); #ifdef CONFIG_KASAN /* @@ -126,13 +127,13 @@ extern int __init efi_memblock_x86_reserve_range(void); extern pgd_t * __init efi_call_phys_prolog(void); extern void __init efi_call_phys_epilog(pgd_t *save_pgd); extern void __init efi_print_memmap(void); -extern void __init efi_memory_uc(u64 addr, unsigned long size); -extern void __init efi_map_region(efi_memory_desc_t *md); +extern void __efi_init_fixup efi_memory_uc(u64 addr, unsigned long size); +extern void __efi_init_fixup efi_map_region(efi_memory_desc_t *md); extern void __init efi_map_region_fixed(efi_memory_desc_t *md); extern void efi_sync_low_kernel_mappings(void); extern int __init efi_alloc_page_tables(void); extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages); -extern void __init old_map_region(efi_memory_desc_t *md); +extern void __efi_init_fixup old_map_region(efi_memory_desc_t *md); extern void __init runtime_code_page_mkexec(void); extern void __init efi_runtime_update_mappings(void); extern void __init efi_dump_pagetable(void); diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 9061babfbc83..439c2c40bf03 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -572,7 +572,7 @@ void __init runtime_code_page_mkexec(void) } } -void __init efi_memory_uc(u64 addr, unsigned long size) +void __efi_init_fixup efi_memory_uc(u64 addr, unsigned long size) { unsigned long page_shift = 1UL << EFI_PAGE_SHIFT; u64 npages; @@ -582,7 +582,7 @@ void __init efi_memory_uc(u64 addr, unsigned long size) set_memory_uc(addr, npages); } -void __init old_map_region(efi_memory_desc_t *md) +void __efi_init_fixup old_map_region(efi_memory_desc_t *md) { u64 start_pfn, end_pfn, end; unsigned long size; diff --git a/arch/x86/platform/efi/efi_32.c b/arch/x86/platform/efi/efi_32.c index 324b93328b37..8f31452bd204 100644 --- a/arch/x86/platform/efi/efi_32.c +++ b/arch/x86/platform/efi/efi_32.c @@ -58,7 +58,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) return 0; } -void __init efi_map_region(efi_memory_desc_t *md) +void __efi_init_fixup efi_map_region(efi_memory_desc_t *md) { old_map_region(md); } diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 448267f1c073..a04298312fdd 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -408,7 +408,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) return 0; } -static void __init __map_region(efi_memory_desc_t *md, u64 va) +static void __efi_init_fixup __map_region(efi_memory_desc_t *md, u64 va) { unsigned long flags = _PAGE_RW; unsigned long pfn; @@ -426,7 +426,7 @@ static void __init __map_region(efi_memory_desc_t *md, u64 va) md->phys_addr, va); } -void __init efi_map_region(efi_memory_desc_t *md) +void __efi_init_fixup efi_map_region(efi_memory_desc_t *md) { unsigned long size = md->num_pages << PAGE_SHIFT; u64 pa = md->phys_addr; @@ -488,8 +488,9 @@ void __init efi_map_region_fixed(efi_memory_desc_t *md) __map_region(md, md->virt_addr); } -void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size, - u32 type, u64 attribute) +void __iomem *__efi_init_fixup efi_ioremap(unsigned long phys_addr, + unsigned long size, u32 type, + u64 attribute) { unsigned long last_map_pfn; diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index d8a33a781a57..7bc3fac7bfe0 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -768,7 +768,7 @@ int __init efi_get_fdt_params(struct efi_fdt_params *params) } #endif /* CONFIG_EFI_PARAMS_FROM_FDT */ -static __initdata char memory_type_name[][20] = { +static __efi_initdata_fixup char memory_type_name[][20] = { "Reserved", "Loader Code", "Loader Data", @@ -786,8 +786,8 @@ static __initdata char memory_type_name[][20] = { "Persistent Memory", }; -char * __init efi_md_typeattr_format(char *buf, size_t size, - const efi_memory_desc_t *md) +char * __efi_init_fixup efi_md_typeattr_format(char *buf, size_t size, + const efi_memory_desc_t *md) { char *pos; int type_len; diff --git a/include/linux/efi.h b/include/linux/efi.h index 855992b15269..0ddd61b9a3e1 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1107,11 +1107,23 @@ extern int efi_memattr_apply_permissions(struct mm_struct *mm, for_each_efi_memory_desc_in_map(&efi.memmap, md) /* + * __efi_init_fixup - if CONFIG_EFI_WARN_ON_ILLEGAL_ACCESS is enabled, + * remove __init modifier. + */ +#ifdef CONFIG_EFI_WARN_ON_ILLEGAL_ACCESS +#define __efi_init_fixup +#define __efi_initdata_fixup +#else +#define __efi_init_fixup __init +#define __efi_initdata_fixup __initdata +#endif + +/* * Format an EFI memory descriptor's type and attributes to a user-provided * character buffer, as per snprintf(), and return the buffer. */ -char * __init efi_md_typeattr_format(char *buf, size_t size, - const efi_memory_desc_t *md); +char * __efi_init_fixup efi_md_typeattr_format(char *buf, size_t size, + const efi_memory_desc_t *md); /** * efi_range_is_wc - check the WC bit on an address range -- 2.7.4