From patchwork Tue Sep 12 09:01:02 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ard Biesheuvel X-Patchwork-Id: 724057 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 1268FCA0EC3 for ; Tue, 12 Sep 2023 09:02:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233254AbjILJC4 (ORCPT ); Tue, 12 Sep 2023 05:02:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37788 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233238AbjILJB5 (ORCPT ); Tue, 12 Sep 2023 05:01:57 -0400 Received: from mail-yw1-x1149.google.com (mail-yw1-x1149.google.com [IPv6:2607:f8b0:4864:20::1149]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A8E7A1706 for ; Tue, 12 Sep 2023 02:01:53 -0700 (PDT) Received: by mail-yw1-x1149.google.com with SMTP id 00721157ae682-59b5a586da6so72362607b3.1 for ; Tue, 12 Sep 2023 02:01:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1694509313; x=1695114113; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=VKh367hgmQvZD8a+n/+xOMhd8K9Jz3TJJTXcd9sGb+U=; b=ou8mb1n8R8OfOF8DpWyJTPJjPaHy9UxdkmUcIvkT+Txd5BeGnOBv9fWe3XzLcyHJy8 gZL3Z9u7ZTCcvm3oARPD/dmE6P3ubLa986xCYhfHRQSA8IWHVQkiWZ8tsGdMyAONI+71 jTLbBUrXPEPlkV4g7xZ/uueK9l5SE8DGM0+0kH0/f8YB35X+XTgiSxV4DbnbsyC8wmAT V+1ZrzkgoD8zyXZIX4l0CTq9M6VBokzPrlXwnwkwiJEZacVu67CQaLRaoXwdYIwE2bZ8 XfjCzKxi4tNcd/2VcwvyOozrLfa+0lApg2nFLMsn6Dc3RX1pGne3v940Y3UrD6MR8Ddp n4XQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694509313; x=1695114113; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=VKh367hgmQvZD8a+n/+xOMhd8K9Jz3TJJTXcd9sGb+U=; b=MmP39pwhxLQ5xS2eHhWfxbRCqMwufrXOWCvMsgg7ZSxNAw9AMmUbnBdfdV5IHrDlIx Wf39uzMUoJLZF7StIdzCNb3AAqBcyyf4rqFW9nKSMHJQVn6hfPzIWO71rJvnVVnhm1sa 4ihHElptcQFCxJNfJ1eNJ3Qm8T2OiTULdLRvA4C4OOCedtgsZyGSlJU5mmKJ24epmrvE JsGDf6cCjZiRunB0HusyEXo1iYDZdHHP7zWRiVqemhkrhTYYxZJFAahq6Ozh5/tgXODn FXW/mXDkadWbjViA4SCTCYqnaCyDsI7tiYreEWOqZz+C018CQah0KOThUFuaCJ23yxhC ozkQ== X-Gm-Message-State: AOJu0Yzv6jpQ5K+Qv+zERNjttDPnEBHETitSmNbcIiBtfqHMI8NHn7Gg 3qEMfuyALCsedqbV8b5KuCj9r19b21CqrZBcnvFRQSIEswFDL0ceR/4C3Jv71DxSZ9vwWYsMBu9 E5LQjDaLONaN4wTodCO64unIlGsnRUmp9KxZ2ibHHsGG4vkicSJ5EZAg2iFLc X-Google-Smtp-Source: AGHT+IHwI0wHd6qPiDSN8OHNFljMj0VCSDsMSABYq2GJME5mvkxJkGZ0iTOYF3Z8sPZrkQJa2D9Zqzef X-Received: from palermo.c.googlers.com ([fda3:e722:ac3:cc00:28:9cb1:c0a8:118a]) (user=ardb job=sendgmr) by 2002:a81:c40e:0:b0:58c:e8da:4d1a with SMTP id j14-20020a81c40e000000b0058ce8da4d1amr61791ywi.2.1694509312588; Tue, 12 Sep 2023 02:01:52 -0700 (PDT) Date: Tue, 12 Sep 2023 09:01:02 +0000 In-Reply-To: <20230912090051.4014114-17-ardb@google.com> Mime-Version: 1.0 References: <20230912090051.4014114-17-ardb@google.com> X-Developer-Key: i=ardb@kernel.org; a=openpgp; fpr=F43D03328115A198C90016883D200E9CA6329909 X-Developer-Signature: v=1; a=openpgp-sha256; l=5004; i=ardb@kernel.org; h=from:subject; bh=+O/KFdhMJMnIogIj3fdlcqOX6X2/aP+6Tar/b+0W/54=; b=owGbwMvMwCFmkMcZplerG8N4Wi2JIZVB46KSnd5N17n3tPfuFGZf7fRs36pVBsa7Eq2S0g/P+ CX8UUago5SFQYyDQVZMkUVg9t93O09PlKp1niULM4eVCWQIAxenAEzkMhsjw31Ws41CYrt4tKQu CtRPdEjfxbx39gx7q1VFOqk5cwwecjEynOTWYdZWnFDndK35rH7PrlXXbmoodPnF+fOzxdjxrsx kAgA= X-Mailer: git-send-email 2.42.0.283.g2d96d420d3-goog Message-ID: <20230912090051.4014114-28-ardb@google.com> Subject: [PATCH v2 11/15] x86/boot: Derive file size from _edata symbol From: Ard Biesheuvel To: linux-efi@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Ard Biesheuvel , Evgeniy Baskov , Borislav Petkov , Dave Hansen , Ingo Molnar , Thomas Gleixner , Peter Jones , Matthew Garrett , Gerd Hoffmann , Kees Cook , "H. Peter Anvin" Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org From: Ard Biesheuvel Tweak the linker script so that the value of _edata represents the decompressor binary's file size rounded up to the appropriate alignment. This removes the need to calculate it in the build tool, and will make it easier to refer to the file size from the header directly in subsequent changes to the PE header layout. While adding _edata to the sed regex that parses the compressed vmlinux's symbol list, tweak the regex a bit for conciseness. This change has no impact on the resulting bzImage binary when configured with CONFIG_EFI_STUB=y. Signed-off-by: Ard Biesheuvel --- arch/x86/boot/Makefile | 2 +- arch/x86/boot/compressed/vmlinux.lds.S | 3 ++ arch/x86/boot/header.S | 2 +- arch/x86/boot/tools/build.c | 30 +++++--------------- 4 files changed, 12 insertions(+), 25 deletions(-) diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile index 0e98bc503699..cc04917b1ac6 100644 --- a/arch/x86/boot/Makefile +++ b/arch/x86/boot/Makefile @@ -89,7 +89,7 @@ $(obj)/vmlinux.bin: $(obj)/compressed/vmlinux FORCE SETUP_OBJS = $(addprefix $(obj)/,$(setup-y)) -sed-zoffset := -e 's/^\([0-9a-fA-F]*\) [a-zA-Z] \(startup_32\|efi32_stub_entry\|efi64_stub_entry\|efi_pe_entry\|efi32_pe_entry\|input_data\|kernel_info\|_end\|_ehead\|_text\|z_.*\)$$/\#define ZO_\2 0x\1/p' +sed-zoffset := -e 's/^\([0-9a-fA-F]*\) [a-zA-Z] \(startup_32\|efi.._stub_entry\|efi\(32\)\?_pe_entry\|input_data\|kernel_info\|_end\|_ehead\|_text\|_edata\|z_.*\)$$/\#define ZO_\2 0x\1/p' quiet_cmd_zoffset = ZOFFSET $@ cmd_zoffset = $(NM) $< | sed -n $(sed-zoffset) > $@ diff --git a/arch/x86/boot/compressed/vmlinux.lds.S b/arch/x86/boot/compressed/vmlinux.lds.S index 4ff6ab1b67d9..5326f3b44194 100644 --- a/arch/x86/boot/compressed/vmlinux.lds.S +++ b/arch/x86/boot/compressed/vmlinux.lds.S @@ -47,6 +47,9 @@ SECTIONS _data = . ; *(.data) *(.data.*) + + /* add 4 bytes of extra space for a CRC-32 checksum */ + . = ALIGN(. + 4, 0x20); _edata = . ; } . = ALIGN(L1_CACHE_BYTES); diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S index 06bd72a324c1..34e9b35b827c 100644 --- a/arch/x86/boot/header.S +++ b/arch/x86/boot/header.S @@ -233,7 +233,7 @@ sentinel: .byte 0xff, 0xff /* Used to detect broken loaders */ hdr: .byte setup_sects - 1 root_flags: .word ROOT_RDONLY -syssize: .long 0 /* Filled in by build.c */ +syssize: .long ZO__edata / 16 ram_size: .word 0 /* Obsolete */ vid_mode: .word SVGA_MODE root_dev: .word 0 /* Default to major/minor 0/0 */ diff --git a/arch/x86/boot/tools/build.c b/arch/x86/boot/tools/build.c index 745d64b6d930..e792c6c5a634 100644 --- a/arch/x86/boot/tools/build.c +++ b/arch/x86/boot/tools/build.c @@ -52,6 +52,7 @@ u8 buf[SETUP_SECT_MAX*512]; static unsigned long efi_pe_entry; static unsigned long efi32_pe_entry; +static unsigned long _edata; static unsigned long _end; /*----------------------------------------------------------------------*/ @@ -308,6 +309,7 @@ static void parse_zoffset(char *fname) while (p && *p) { PARSE_ZOFS(p, efi_pe_entry); PARSE_ZOFS(p, efi32_pe_entry); + PARSE_ZOFS(p, _edata); PARSE_ZOFS(p, _end); p = strchr(p, '\n'); @@ -320,7 +322,6 @@ int main(int argc, char ** argv) { unsigned int i, sz, setup_sectors; int c; - u32 sys_size; struct stat sb; FILE *file, *dest; int fd; @@ -368,24 +369,14 @@ int main(int argc, char ** argv) die("Unable to open `%s': %m", argv[2]); if (fstat(fd, &sb)) die("Unable to stat `%s': %m", argv[2]); - sz = sb.st_size; + if (_edata != sb.st_size) + die("Unexpected file size `%s': %u != %u", argv[2], _edata, + sb.st_size); + sz = _edata - 4; kernel = mmap(NULL, sz, PROT_READ, MAP_SHARED, fd, 0); if (kernel == MAP_FAILED) die("Unable to mmap '%s': %m", argv[2]); - /* Number of 16-byte paragraphs, including space for a 4-byte CRC */ - sys_size = (sz + 15 + 4) / 16; -#ifdef CONFIG_EFI_STUB - /* - * COFF requires minimum 32-byte alignment of sections, and - * adding a signature is problematic without that alignment. - */ - sys_size = (sys_size + 1) & ~1; -#endif - - /* Patch the setup code with the appropriate size parameters */ - put_unaligned_le32(sys_size, &buf[0x1f4]); - - update_pecoff_text(setup_sectors * 512, i + (sys_size * 16)); + update_pecoff_text(setup_sectors * 512, i + _edata); crc = partial_crc32(buf, i, crc); @@ -397,13 +388,6 @@ int main(int argc, char ** argv) if (fwrite(kernel, 1, sz, dest) != sz) die("Writing kernel failed"); - /* Add padding leaving 4 bytes for the checksum */ - while (sz++ < (sys_size*16) - 4) { - crc = partial_crc32_one('\0', crc); - if (fwrite("\0", 1, 1, dest) != 1) - die("Writing padding failed"); - } - /* Write the CRC */ put_unaligned_le32(crc, buf); if (fwrite(buf, 1, 4, dest) != 4)