From: Ard Biesheuvel <ardb@google.com>
To: linux-efi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, Ard Biesheuvel <ardb@kernel.org>,
Evgeniy Baskov <baskov@ispras.ru>, Borislav Petkov <bp@alien8.de>,
Dave Hansen <dave.hansen@linux.intel.com>,
Ingo Molnar <mingo@redhat.com>,
Thomas Gleixner <tglx@linutronix.de>,
Peter Jones <pjones@redhat.com>,
Matthew Garrett <mjg59@srcf.ucam.org>,
Gerd Hoffmann <kraxel@redhat.com>,
Kees Cook <keescook@chromium.org>,
"H. Peter Anvin" <hpa@zytor.com>
Subject: [PATCH v2 14/15] x86/boot: Split off PE/COFF .data section
Date: Tue, 12 Sep 2023 09:01:05 +0000 [thread overview]
Message-ID: <20230912090051.4014114-31-ardb@google.com> (raw)
In-Reply-To: <20230912090051.4014114-17-ardb@google.com>
From: Ard Biesheuvel <ardb@kernel.org>
Describe the code and data of the decompressor binary using separate
.text and .data PE/COFF sections, so that we will be able to map them
using restricted permissions once we increase the section and file
alignment sufficiently. This avoids the need for memory mappings that
are writable and executable at the same time, which is something that
is best avoided for security reasons.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
arch/x86/boot/Makefile | 2 +-
| 19 +++++++++++++++----
2 files changed, 16 insertions(+), 5 deletions(-)
diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index cc04917b1ac6..3cece19b7473 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\|efi.._stub_entry\|efi\(32\)\?_pe_entry\|input_data\|kernel_info\|_end\|_ehead\|_text\|_edata\|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\|_e\?data\|z_.*\)$$/\#define ZO_\2 0x\1/p'
quiet_cmd_zoffset = ZOFFSET $@
cmd_zoffset = $(NM) $< | sed -n $(sed-zoffset) > $@
--git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index 9e9641e220a7..a1f986105f00 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -75,9 +75,9 @@ optional_header:
.byte 0x02 # MajorLinkerVersion
.byte 0x14 # MinorLinkerVersion
- .long setup_size + ZO__end - 0x200 # SizeOfCode
+ .long ZO__data # SizeOfCode
- .long 0 # SizeOfInitializedData
+ .long ZO__end - ZO__data # SizeOfInitializedData
.long 0 # SizeOfUninitializedData
.long setup_size + ZO_efi_pe_entry # AddressOfEntryPoint
@@ -178,9 +178,9 @@ section_table:
.byte 0
.byte 0
.byte 0
- .long ZO__end
+ .long ZO__data
.long setup_size
- .long ZO__edata # Size of initialized data
+ .long ZO__data # Size of initialized data
# on disk
.long setup_size
.long 0 # PointerToRelocations
@@ -191,6 +191,17 @@ section_table:
IMAGE_SCN_MEM_READ | \
IMAGE_SCN_MEM_EXECUTE # Characteristics
+ .ascii ".data\0\0\0"
+ .long ZO__end - ZO__data # VirtualSize
+ .long setup_size + ZO__data # VirtualAddress
+ .long ZO__edata - ZO__data # SizeOfRawData
+ .long setup_size + ZO__data # PointerToRawData
+
+ .long 0, 0, 0
+ .long IMAGE_SCN_CNT_INITIALIZED_DATA | \
+ IMAGE_SCN_MEM_READ | \
+ IMAGE_SCN_MEM_WRITE # Characteristics
+
.set section_count, (. - section_table) / 40
#endif /* CONFIG_EFI_STUB */
--
2.42.0.283.g2d96d420d3-goog
next prev parent reply other threads:[~2023-09-12 9:03 UTC|newest]
Thread overview: 41+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-12 9:00 [PATCH v2 00/15] x86/boot: Rework PE header generation Ard Biesheuvel
2023-09-12 9:00 ` [PATCH v2 01/15] x86/efi: Drop EFI stub .bss from .data section Ard Biesheuvel
2023-09-15 9:37 ` [tip: x86/boot] " tip-bot2 for Ard Biesheuvel
2023-09-12 9:00 ` [PATCH v2 02/15] x86/efi: Disregard setup header of loaded image Ard Biesheuvel
2023-09-15 9:37 ` [tip: x86/boot] " tip-bot2 for Ard Biesheuvel
2023-09-12 9:00 ` [PATCH v2 03/15] x86/efi: Drop alignment flags from PE section headers Ard Biesheuvel
2023-09-15 9:37 ` [tip: x86/boot] " tip-bot2 for Ard Biesheuvel
2023-09-12 9:00 ` [PATCH v2 04/15] x86/boot: Remove the 'bugger off' message Ard Biesheuvel
2023-09-15 9:37 ` [tip: x86/boot] " tip-bot2 for Ard Biesheuvel
2023-09-12 9:00 ` [PATCH v2 05/15] x86/boot: Omit compression buffer from PE/COFF image memory footprint Ard Biesheuvel
2023-09-15 9:37 ` [tip: x86/boot] " tip-bot2 for Ard Biesheuvel
2023-09-12 9:00 ` [PATCH v2 06/15] x86/boot: Drop redundant code setting the root device Ard Biesheuvel
2023-09-15 9:37 ` [tip: x86/boot] " tip-bot2 for Ard Biesheuvel
2023-09-12 9:00 ` [PATCH v2 07/15] x86/boot: Grab kernel_info offset from zoffset header directly Ard Biesheuvel
2023-09-12 9:00 ` [PATCH v2 08/15] x86/boot: Drop references to startup_64 Ard Biesheuvel
2023-09-15 9:15 ` Ingo Molnar
2023-09-15 13:48 ` Ard Biesheuvel
2023-09-15 15:40 ` Ingo Molnar
2023-09-15 15:45 ` Ingo Molnar
2023-09-15 15:48 ` Ard Biesheuvel
2023-09-15 9:37 ` [tip: x86/boot] " tip-bot2 for Ard Biesheuvel
2023-09-12 9:01 ` [PATCH v2 09/15] x86/boot: Set EFI handover offset directly in header asm Ard Biesheuvel
2023-09-12 9:01 ` [PATCH v2 10/15] x86/boot: Define setup size in linker script Ard Biesheuvel
2023-09-15 9:37 ` [tip: x86/boot] " tip-bot2 for Ard Biesheuvel
2023-09-12 9:01 ` [PATCH v2 11/15] x86/boot: Derive file size from _edata symbol Ard Biesheuvel
2023-09-12 9:01 ` [PATCH v2 12/15] x86/boot: Construct PE/COFF .text section from assembler Ard Biesheuvel
2023-09-12 9:01 ` [PATCH v2 13/15] x86/boot: Drop PE/COFF .reloc section Ard Biesheuvel
2023-09-12 9:01 ` Ard Biesheuvel [this message]
2023-09-12 9:01 ` [PATCH v2 15/15] x86/boot: Increase section and file alignment to 4k/512 Ard Biesheuvel
2023-09-15 9:22 ` [PATCH v2 00/15] x86/boot: Rework PE header generation Ingo Molnar
2023-09-15 11:30 ` Ingo Molnar
2023-09-15 13:21 ` Ard Biesheuvel
2023-09-15 13:28 ` Ard Biesheuvel
2023-09-16 9:10 ` Ingo Molnar
2023-09-16 19:14 ` Ard Biesheuvel
2023-09-17 17:50 ` Ingo Molnar
2023-10-03 2:02 ` Jan Hendrik Farr
2023-10-23 11:22 ` Ard Biesheuvel
2023-10-23 17:35 ` Jan Hendrik Farr
2023-10-24 8:21 ` Dave Young
2023-10-24 8:31 ` Dave Young
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20230912090051.4014114-31-ardb@google.com \
--to=ardb@google.com \
--cc=ardb@kernel.org \
--cc=baskov@ispras.ru \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=hpa@zytor.com \
--cc=keescook@chromium.org \
--cc=kraxel@redhat.com \
--cc=linux-efi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=mjg59@srcf.ucam.org \
--cc=pjones@redhat.com \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox