@@ -42,6 +42,7 @@ $(obj)/Image.zst: $(obj)/Image FORCE
EFI_ZBOOT_PAYLOAD := Image.zboot
EFI_ZBOOT_BFD_TARGET := elf64-littleaarch64
EFI_ZBOOT_MACH_TYPE := ARM64
+EFI_ZBOOT_FORWARD_CFI := $(CONFIG_ARM64_BTI_KERNEL)
#
# The EFI zboot logic needs to know the size of the executable region in the
@@ -1,7 +1,8 @@
# SPDX-License-Identifier: GPL-2.0
# to be include'd by arch/$(ARCH)/boot/Makefile after setting
-# EFI_ZBOOT_PAYLOAD, EFI_ZBOOT_BFD_TARGET and EFI_ZBOOT_MACH_TYPE
+# EFI_ZBOOT_PAYLOAD, EFI_ZBOOT_BFD_TARGET, EFI_ZBOOT_MACH_TYPE and
+# EFI_ZBOOT_FORWARD_CFI
quiet_cmd_copy_and_pad = PAD $@
cmd_copy_and_pad = cp $< $@ && \
@@ -44,10 +45,14 @@ OBJCOPYFLAGS_vmlinuz.o := -I binary -O $(EFI_ZBOOT_BFD_TARGET) \
$(obj)/vmlinuz.o: $(obj)/vmlinuz FORCE
$(call if_changed,objcopy)
+aflags-zboot-header-$(EFI_ZBOOT_FORWARD_CFI) := \
+ -DPE_DLL_CHAR_EX=IMAGE_DLLCHARACTERISTICS_EX_FORWARD_CFI_COMPAT
+
AFLAGS_zboot-header.o += -DMACHINE_TYPE=IMAGE_FILE_MACHINE_$(EFI_ZBOOT_MACH_TYPE) \
-DZBOOT_EFI_PATH="\"$(realpath $(obj)/vmlinuz.efi.elf)\"" \
-DZBOOT_SIZE_LEN=$(zboot-size-len-y) \
- -DCOMP_TYPE="\"$(comp-type-y)\""
+ -DCOMP_TYPE="\"$(comp-type-y)\"" \
+ $(aflags-zboot-header-y)
$(obj)/zboot-header.o: $(srctree)/drivers/firmware/efi/libstub/zboot-header.S FORCE
$(call if_changed_rule,as_o_S)
@@ -78,9 +78,36 @@ __efistub_efi_zboot_header:
.quad 0 // ExceptionTable
.quad 0 // CertificationTable
.quad 0 // BaseRelocationTable
-#ifdef CONFIG_DEBUG_EFI
+#if defined(PE_DLL_CHAR_EX) || defined(CONFIG_DEBUG_EFI)
.long .Lefi_debug_table - .Ldoshdr // DebugTable
.long .Lefi_debug_table_size
+
+ .section ".rodata", "a"
+ .p2align 2
+.Lefi_debug_table:
+ // EFI_IMAGE_DEBUG_DIRECTORY_ENTRY[]
+#ifdef PE_DLL_CHAR_EX
+ .long 0 // Characteristics
+ .long 0 // TimeDateStamp
+ .short 0 // MajorVersion
+ .short 0 // MinorVersion
+ .long IMAGE_DEBUG_TYPE_EX_DLLCHARACTERISTICS // Type
+ .long 4 // SizeOfData
+ .long 0 // RVA
+ .long .Lefi_dll_characteristics_ex - .Ldoshdr // FileOffset
+#endif
+#ifdef CONFIG_DEBUG_EFI
+ .long 0 // Characteristics
+ .long 0 // TimeDateStamp
+ .short 0 // MajorVersion
+ .short 0 // MinorVersion
+ .long IMAGE_DEBUG_TYPE_CODEVIEW // Type
+ .long .Lefi_debug_entry_size // SizeOfData
+ .long 0 // RVA
+ .long .Lefi_debug_entry - .Ldoshdr // FileOffset
+#endif
+ .set .Lefi_debug_table_size, . - .Lefi_debug_table
+ .previous
#endif
.Lsection_table:
@@ -110,23 +137,11 @@ __efistub_efi_zboot_header:
.set .Lsection_count, (. - .Lsection_table) / 40
+#ifdef PE_DLL_CHAR_EX
+.Lefi_dll_characteristics_ex:
+ .long PE_DLL_CHAR_EX
+#endif
#ifdef CONFIG_DEBUG_EFI
- .section ".rodata", "a"
- .align 2
-.Lefi_debug_table:
- // EFI_IMAGE_DEBUG_DIRECTORY_ENTRY
- .long 0 // Characteristics
- .long 0 // TimeDateStamp
- .short 0 // MajorVersion
- .short 0 // MinorVersion
- .long IMAGE_DEBUG_TYPE_CODEVIEW // Type
- .long .Lefi_debug_entry_size // SizeOfData
- .long 0 // RVA
- .long .Lefi_debug_entry - .Ldoshdr // FileOffset
-
- .set .Lefi_debug_table_size, . - .Lefi_debug_table
- .previous
-
.Lefi_debug_entry:
// EFI_IMAGE_DEBUG_CODEVIEW_NB10_ENTRY
.ascii "NB10" // Signature
Add some plumbing to the zboot EFI header generation to set the newly introduced DllCharacteristicsEx flag associated with forward edge CFI enforcement instructions (BTI on arm64, IBT on x86) x86 does not currently uses the zboot infrastructure, so let's wire it up only for arm64. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> --- arch/arm64/boot/Makefile | 1 + drivers/firmware/efi/libstub/Makefile.zboot | 9 +++- drivers/firmware/efi/libstub/zboot-header.S | 49 +++++++++++++------- 3 files changed, 40 insertions(+), 19 deletions(-)