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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6B10C00144 for ; Mon, 1 Aug 2022 16:39:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233918AbiHAQjf (ORCPT ); Mon, 1 Aug 2022 12:39:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60200 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233281AbiHAQjN (ORCPT ); Mon, 1 Aug 2022 12:39:13 -0400 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4DAA0C0B for ; Mon, 1 Aug 2022 09:39:12 -0700 (PDT) Received: from localhost.localdomain (unknown [92.49.173.143]) by mail.ispras.ru (Postfix) with ESMTPSA id 63EDA4076263; Mon, 1 Aug 2022 16:39:10 +0000 (UTC) From: Evgeniy Baskov To: Borislav Petkov Cc: Evgeniy Baskov , Dave Hansen , Ingo Molnar , Thomas Gleixner , Andy Lutomirski , Peter Zijlstra , x86@kernel.org, linux-kernel@vger.kernel.org, Alexey Khoroshilov Subject: [PATCH 7/8] x86/boot: Map memory explicitly Date: Mon, 1 Aug 2022 19:39:04 +0300 Message-Id: X-Mailer: git-send-email 2.35.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Implicit mappings hide possible memory errors, e.g. allocations for ACPI tables were not included in boot page table size. Replace all implicit mappings from page fault handler with explicit mappings. Signed-off-by: Evgeniy Baskov diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c index 9caf89063e77..633ac56262ee 100644 --- a/arch/x86/boot/compressed/acpi.c +++ b/arch/x86/boot/compressed/acpi.c @@ -93,6 +93,8 @@ static u8 *scan_mem_for_rsdp(u8 *start, u32 length) end = start + length; + kernel_add_identity_map((unsigned long)start, (unsigned long)end, 0); + /* Search from given start address for the requested length */ for (address = start; address < end; address += ACPI_RSDP_SCAN_STEP) { /* @@ -128,6 +130,9 @@ static acpi_physical_address bios_get_rsdp_addr(void) unsigned long address; u8 *rsdp; + kernel_add_identity_map((unsigned long)ACPI_EBDA_PTR_LOCATION, + (unsigned long)ACPI_EBDA_PTR_LOCATION + 2, 0); + /* Get the location of the Extended BIOS Data Area (EBDA) */ address = *(u16 *)ACPI_EBDA_PTR_LOCATION; address <<= 4; @@ -215,6 +220,9 @@ static unsigned long get_acpi_srat_table(void) if (!rsdp) return 0; + kernel_add_identity_map((unsigned long)rsdp, + (unsigned long)(rsdp + 1), 0); + /* Get ACPI root table from RSDP.*/ if (!(cmdline_find_option("acpi", arg, sizeof(arg)) == 4 && !strncmp(arg, "rsdt", 4)) && @@ -235,6 +243,9 @@ static unsigned long get_acpi_srat_table(void) if (len < sizeof(struct acpi_table_header) + size) return 0; + kernel_add_identity_map((unsigned long)header, + (unsigned long)header + len, 0); + num_entries = (len - sizeof(struct acpi_table_header)) / size; entry = (u8 *)(root_table + sizeof(struct acpi_table_header)); @@ -247,8 +258,16 @@ static unsigned long get_acpi_srat_table(void) if (acpi_table) { header = (struct acpi_table_header *)acpi_table; - if (ACPI_COMPARE_NAMESEG(header->signature, ACPI_SIG_SRAT)) + kernel_add_identity_map(acpi_table, + acpi_table + sizeof(*header), + 0); + + if (ACPI_COMPARE_NAMESEG(header->signature, ACPI_SIG_SRAT)) { + kernel_add_identity_map(acpi_table, + acpi_table + header->length, + 0); return acpi_table; + } } entry += size; } diff --git a/arch/x86/boot/compressed/efi.c b/arch/x86/boot/compressed/efi.c index 6edd034b0b30..ce70103fbbc0 100644 --- a/arch/x86/boot/compressed/efi.c +++ b/arch/x86/boot/compressed/efi.c @@ -57,10 +57,14 @@ enum efi_type efi_get_type(struct boot_params *bp) */ unsigned long efi_get_system_table(struct boot_params *bp) { - unsigned long sys_tbl_pa; + static unsigned long sys_tbl_pa __section(".data"); struct efi_info *ei; + unsigned long sys_tbl_size; enum efi_type et; + if (sys_tbl_pa) + return sys_tbl_pa; + /* Get systab from boot params. */ ei = &bp->efi_info; #ifdef CONFIG_X86_64 @@ -73,6 +77,13 @@ unsigned long efi_get_system_table(struct boot_params *bp) return 0; } + if (efi_get_type(bp) == EFI_TYPE_64) + sys_tbl_size = sizeof(efi_system_table_64_t); + else + sys_tbl_size = sizeof(efi_system_table_32_t); + + kernel_add_identity_map(sys_tbl_pa, sys_tbl_pa + sys_tbl_size, 0); + return sys_tbl_pa; } @@ -92,6 +103,10 @@ static struct efi_setup_data *get_kexec_setup_data(struct boot_params *bp, pa_data = bp->hdr.setup_data; while (pa_data) { + unsigned long pa_data_end = pa_data + sizeof(struct setup_data) + + sizeof(struct efi_setup_data); + kernel_add_identity_map(pa_data, pa_data_end, 0); + data = (struct setup_data *)pa_data; if (data->type == SETUP_EFI) { esd = (struct efi_setup_data *)(pa_data + sizeof(struct setup_data)); @@ -160,6 +175,8 @@ int efi_get_conf_table(struct boot_params *bp, unsigned long *cfg_tbl_pa, return -EINVAL; } + kernel_add_identity_map(*cfg_tbl_pa, *cfg_tbl_pa + *cfg_tbl_len, 0); + return 0; } diff --git a/arch/x86/boot/compressed/kaslr.c b/arch/x86/boot/compressed/kaslr.c index 4a3f223973f4..073c7cfbd785 100644 --- a/arch/x86/boot/compressed/kaslr.c +++ b/arch/x86/boot/compressed/kaslr.c @@ -687,6 +687,8 @@ process_efi_entries(unsigned long minimum, unsigned long image_size) u32 nr_desc; int i; + kernel_add_identity_map((unsigned long)e, (unsigned long)(e + 1), 0); + signature = (char *)&e->efi_loader_signature; if (strncmp(signature, EFI32_LOADER_SIGNATURE, 4) && strncmp(signature, EFI64_LOADER_SIGNATURE, 4)) @@ -703,6 +705,8 @@ process_efi_entries(unsigned long minimum, unsigned long image_size) pmap = (e->efi_memmap | ((__u64)e->efi_memmap_hi << 32)); #endif + kernel_add_identity_map(pmap, pmap + e->efi_memmap_size, 0); + nr_desc = e->efi_memmap_size / e->efi_memdesc_size; for (i = 0; i < nr_desc; i++) { md = efi_early_memdesc_ptr(pmap, e->efi_memdesc_size, i); -- 2.35.1