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Aarch64: make section alignment larger #781

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e1fc151
post-process-pe: fix a minor getopt bug
vathpela Oct 28, 2025
f2c9c47
post-process-pe: Move file alignment to context.
vathpela Oct 28, 2025
eebf74b
post-process-pe: Add debug and tests to the FileAlignment header.
vathpela Oct 28, 2025
c83c5c0
post-process-pe: be better at section alignment complaints
vathpela Oct 28, 2025
e37e76d
post-process-pe: complain about section VMA alignment
vathpela Oct 28, 2025
85ea272
make: set PE section alignment everywhere
vathpela Oct 28, 2025
9a8b9f3
Aarch64: use bigger section alignment
vathpela Oct 22, 2025
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4 changes: 4 additions & 0 deletions Make.defaults
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Original file line number Diff line number Diff line change
Expand Up @@ -68,6 +68,7 @@ ifeq ($(ARCH),x86_64)
ARCH_SUFFIX ?= x64
ARCH_SUFFIX_UPPER ?= X64
ARCH_LDFLAGS ?=
ARCH_SECTION_ALIGNMENT ?= 0x1000
endif
ifeq ($(ARCH),ia32)
ARCH_CFLAGS ?= -mno-mmx -mno-sse -mno-red-zone -nostdinc \
Expand All @@ -78,6 +79,7 @@ ifeq ($(ARCH),ia32)
ARCH_SUFFIX_UPPER ?= IA32
ARCH_LDFLAGS ?=
ARCH_CFLAGS ?= -m32
ARCH_SECTION_ALIGNMENT ?= 0x1000
endif
ifeq ($(ARCH),aarch64)
ARCH_CFLAGS ?= -DMDE_CPU_AARCH64 -DPAGE_SIZE=4096 -mstrict-align
Expand All @@ -86,6 +88,7 @@ ifeq ($(ARCH),aarch64)
ARCH_SUFFIX_UPPER ?= AA64
ARCH_LDFLAGS ?=
ARCH_CFLAGS ?=
ARCH_SECTION_ALIGNMENT ?= 0x10000
endif
ifeq ($(ARCH),arm)
ARCH_CFLAGS ?= -DMDE_CPU_ARM -DPAGE_SIZE=4096 -mno-unaligned-access
Expand All @@ -95,6 +98,7 @@ ifeq ($(ARCH),arm)
FORMAT := -O binary
SUBSYSTEM := 0xa
ARCH_LDFLAGS += --defsym=EFI_SUBSYSTEM=$(SUBSYSTEM)
ARCH_SECTION_ALIGNMENT ?= 0x1000
endif

DEFINES = -DDEFAULT_LOADER='L"$(DEFAULT_LOADER)"' \
Expand Down
2 changes: 2 additions & 0 deletions Makefile
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Expand Up @@ -282,6 +282,7 @@ endif
-j .rela* -j .dyn -j .reloc -j .eh_frame \
-j .vendor_cert -j .sbat -j .sbatlevel \
--file-alignment 0x1000 \
--section-alignment $(ARCH_SECTION_ALIGNMENT) \
$(FORMAT) $< $@
./post-process-pe -vv $(POST_PROCESS_PE_FLAGS) $@

Expand All @@ -302,6 +303,7 @@ endif
-j .debug_line -j .debug_str -j .debug_ranges \
-j .note.gnu.build-id \
--file-alignment 0x1000 \
--section-alignment $(ARCH_SECTION_ALIGNMENT) \
$< $@

ifneq ($(origin ENABLE_SBSIGN),undefined)
Expand Down
28 changes: 14 additions & 14 deletions elf_aarch64_efi.lds
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Original file line number Diff line number Diff line change
Expand Up @@ -6,12 +6,12 @@ SECTIONS
. = 0;
ImageBase = .;
.hash : { *(.hash) } /* this MUST come first! */
. = ALIGN(4096);
. = ALIGN(65536);
.eh_frame :
{
*(.eh_frame)
}
. = ALIGN(4096);
. = ALIGN(65536);
.text :
{
_text = .;
Expand All @@ -20,26 +20,26 @@ SECTIONS
*(.gnu.linkonce.t.*)
_etext = .;
}
. = ALIGN(4096);
. = ALIGN(65536);
.reloc :
{
*(.reloc)
}
. = ALIGN(4096);
. = ALIGN(65536);
.note.gnu.build-id : {
*(.note.gnu.build-id)
}

. = ALIGN(4096);
. = ALIGN(65536);
.data.ident : {
*(.data.ident)
}
. = ALIGN(4096);
. = ALIGN(65536);
.sbatlevel : {
*(.sbatlevel)
}

. = ALIGN(4096);
. = ALIGN(65536);
.data :
{
_data = .;
Expand All @@ -58,14 +58,14 @@ SECTIONS
*(.rel.local)
}

. = ALIGN(4096);
. = ALIGN(65536);
.vendor_cert :
{
*(.vendor_cert)
}
. = ALIGN(4096);
. = ALIGN(65536);
.dynamic : { *(.dynamic) }
. = ALIGN(4096);
. = ALIGN(65536);
.rela :
{
*(.rela.data*)
Expand All @@ -74,7 +74,7 @@ SECTIONS
}
_edata = .;
_data_size = . - _data;
. = ALIGN(4096);
. = ALIGN(65536);
.sbat :
{
_sbat = .;
Expand All @@ -84,11 +84,11 @@ SECTIONS
_esbat = .;
_sbat_size = . - _sbat;

. = ALIGN(4096);
. = ALIGN(65536);
.dynsym : { *(.dynsym) }
. = ALIGN(4096);
. = ALIGN(65536);
.dynstr : { *(.dynstr) }
. = ALIGN(4096);
. = ALIGN(65536);
.ignored.reloc :
{
*(.rela.reloc)
Expand Down
1 change: 1 addition & 0 deletions include/peimage.h
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Expand Up @@ -819,6 +819,7 @@ typedef struct {
UINTN SizeOfHeaders;
UINT16 ImageType;
UINT16 NumberOfSections;
UINT32 FileAlignment;
UINT32 SectionAlignment;
EFI_IMAGE_SECTION_HEADER *FirstSection;
EFI_IMAGE_DATA_DIRECTORY *RelocDir;
Expand Down
40 changes: 29 additions & 11 deletions post-process-pe.c
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Original file line number Diff line number Diff line change
Expand Up @@ -124,7 +124,6 @@ load_pe(const char *const file, void *const data, const size_t datasize,
EFI_IMAGE_DOS_HEADER *DOSHdr = data;
EFI_IMAGE_OPTIONAL_HEADER_UNION *PEHdr = data;
size_t HeaderWithoutDataDir, SectionHeaderOffset, OptHeaderSize;
size_t FileAlignment = 0;
size_t sz0 = 0, sz1 = 0;
uintptr_t loc = 0;

Expand Down Expand Up @@ -164,7 +163,7 @@ load_pe(const char *const file, void *const data, const size_t datasize,
ctx->SectionAlignment =
PEHdr->Pe32Plus.OptionalHeader.SectionAlignment;
ctx->DllCharacteristics = PEHdr->Pe32Plus.OptionalHeader.DllCharacteristics;
FileAlignment = PEHdr->Pe32Plus.OptionalHeader.FileAlignment;
ctx->FileAlignment = PEHdr->Pe32Plus.OptionalHeader.FileAlignment;
OptHeaderSize = sizeof(EFI_IMAGE_OPTIONAL_HEADER64);
} else {
debug(NOISE, "image is 32bit\n");
Expand All @@ -175,19 +174,19 @@ load_pe(const char *const file, void *const data, const size_t datasize,
ctx->SectionAlignment =
PEHdr->Pe32.OptionalHeader.SectionAlignment;
ctx->DllCharacteristics = PEHdr->Pe32.OptionalHeader.DllCharacteristics;
FileAlignment = PEHdr->Pe32.OptionalHeader.FileAlignment;
ctx->FileAlignment = PEHdr->Pe32.OptionalHeader.FileAlignment;
OptHeaderSize = sizeof(EFI_IMAGE_OPTIONAL_HEADER32);
}

if (FileAlignment % 2 != 0)
errx(1, "%s: Invalid file alignment %zu", file, FileAlignment);
if (ctx->FileAlignment % 2 != 0)
errx(1, "%s: Invalid file alignment 0x%08x", file, ctx->FileAlignment);

if (FileAlignment == 0)
FileAlignment = 0x200;
if (ctx->FileAlignment == 0)
ctx->FileAlignment = 0x200;
if (ctx->SectionAlignment == 0)
ctx->SectionAlignment = PAGE_SIZE;
if (ctx->SectionAlignment < FileAlignment)
ctx->SectionAlignment = FileAlignment;
if (ctx->SectionAlignment < ctx->FileAlignment)
ctx->SectionAlignment = ctx->FileAlignment;

ctx->NumberOfSections = PEHdr->Pe32.FileHeader.NumberOfSections;

Expand Down Expand Up @@ -382,10 +381,19 @@ validate_nx_compat(PE_COFF_LOADER_IMAGE_CONTEXT *ctx)
ret = -1;
}

debug(NOISE, "File alignment is 0x%x, page size is 0x%x\n",
ctx->FileAlignment, PAGE_SIZE);
if (ctx->FileAlignment % PAGE_SIZE != 0) {
debug(level, "File alignment is not a multiple of page size\n");
if (require_nx_compat)
ret = -1;
}

debug(NOISE, "Section alignment is 0x%x, page size is 0x%x\n",
ctx->SectionAlignment, PAGE_SIZE);
if (ctx->SectionAlignment != PAGE_SIZE) {
debug(level, "Section alignment is not page aligned\n");
if (ctx->SectionAlignment & (PAGE_SIZE - 1)) {
debug(level, "Section alignment is not page aligned: SectionAlignment & PAGE_MASK = 0x%08x & 0x%08x = 0x%08x\n",
ctx->SectionAlignment, PAGE_SIZE-1, ctx->SectionAlignment & (PAGE_SIZE-1));
if (require_nx_compat)
ret = -1;
}
Expand All @@ -402,6 +410,13 @@ validate_nx_compat(PE_COFF_LOADER_IMAGE_CONTEXT *ctx)
if (require_nx_compat)
ret = -1;
}

debug(NOISE, "Section %d has VA of 0x%08x\n", i, Section->VirtualAddress);
if (Section->VirtualAddress != 0 &&
((Section->VirtualAddress) & (ctx->SectionAlignment - 1))) {
debug(level, "Section %d has Virtual Address 0x%08x that isn't section aligned (0x%08x)\n",
i, Section->VirtualAddress, ctx->SectionAlignment);
}
}

return ret;
Expand Down Expand Up @@ -590,6 +605,9 @@ int main(int argc, char **argv)
case 'x':
require_nx_compat = true;
break;
default:
usage(1);
break;
}
}

Expand Down
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