[PATCH v17 5/9] x86/objtool: Add directory and file whitelists

[Josh Poimboeuf]

Tell objtool to skip validation of the following code which runs
outside the kernel's normal mode of operation:

- boot image
- vdso image
- relocation
- realmode
- efi
- head

Also, skip the following code which does the right thing with respect to
frame pointers, but is too "special" to be validated by a tool:

- entry
- mcount

Also skip the test_nx module because it modifies its exception handling
table at runtime, which objtool can't understand.  Fortunately it's
just a test module so it doesn't matter much.

Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
 arch/x86/boot/Makefile                |  3 ++-
 arch/x86/boot/compressed/Makefile     |  3 ++-
 arch/x86/entry/Makefile               |  4 ++++
 arch/x86/entry/vdso/Makefile          |  6 ++++--
 arch/x86/kernel/Makefile              | 11 ++++++++---
 arch/x86/platform/efi/Makefile        |  2 ++
 arch/x86/realmode/Makefile            |  4 +++-
 arch/x86/realmode/rm/Makefile         |  3 ++-
 drivers/firmware/efi/libstub/Makefile |  1 +
 9 files changed, 28 insertions(+), 9 deletions(-)

diff --git a/arch/x86/boot/Makefile b/arch/x86/boot/Makefile
index bbe1a62..0bf6749 100644
--- a/arch/x86/boot/Makefile
+++ b/arch/x86/boot/Makefile
@@ -9,7 +9,8 @@
 # Changed by many, many contributors over the years.
 #
 
-KASAN_SANITIZE := n
+KASAN_SANITIZE			:= n
+OBJECT_FILES_NON_STANDARD	:= y
 
 # If you want to preset the SVGA mode, uncomment the next line and
 # set SVGA_MODE to whatever number you want.
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index f9ce75d..5e1d26e 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -16,7 +16,8 @@
 #	(see scripts/Makefile.lib size_append)
 #	compressed vmlinux.bin.all + u32 size of vmlinux.bin.all
 
-KASAN_SANITIZE := n
+KASAN_SANITIZE			:= n
+OBJECT_FILES_NON_STANDARD	:= y
 
 targets := vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma \
 	vmlinux.bin.xz vmlinux.bin.lzo vmlinux.bin.lz4
diff --git a/arch/x86/entry/Makefile b/arch/x86/entry/Makefile
index bd55ded..fe91c25 100644
--- a/arch/x86/entry/Makefile
+++ b/arch/x86/entry/Makefile
@@ -1,6 +1,10 @@
 #
 # Makefile for the x86 low level entry code
 #
+
+OBJECT_FILES_NON_STANDARD_entry_$(BITS).o   := y
+OBJECT_FILES_NON_STANDARD_entry_64_compat.o := y
+
 obj-y				:= entry_$(BITS).o thunk_$(BITS).o syscall_$(BITS).o
 obj-y				+= common.o
 
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
index c854541..f9fb859 100644
--- a/arch/x86/entry/vdso/Makefile
+++ b/arch/x86/entry/vdso/Makefile
@@ -3,8 +3,9 @@
 #
 
 KBUILD_CFLAGS += $(DISABLE_LTO)
-KASAN_SANITIZE := n
-UBSAN_SANITIZE := n
+KASAN_SANITIZE			:= n
+UBSAN_SANITIZE			:= n
+OBJECT_FILES_NON_STANDARD	:= y
 
 VDSO64-$(CONFIG_X86_64)		:= y
 VDSOX32-$(CONFIG_X86_X32_ABI)	:= y
@@ -16,6 +17,7 @@ vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o
 
 # files to link into kernel
 obj-y				+= vma.o
+OBJECT_FILES_NON_STANDARD_vma.o	:= n
 
 # vDSO images to build
 vdso_img-$(VDSO64-y)		+= 64
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index b1b78ff..d5fb087 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -16,9 +16,14 @@ CFLAGS_REMOVE_ftrace.o = -pg
 CFLAGS_REMOVE_early_printk.o = -pg
 endif
 
-KASAN_SANITIZE_head$(BITS).o := n
-KASAN_SANITIZE_dumpstack.o := n
-KASAN_SANITIZE_dumpstack_$(BITS).o := n
+KASAN_SANITIZE_head$(BITS).o				:= n
+KASAN_SANITIZE_dumpstack.o				:= n
+KASAN_SANITIZE_dumpstack_$(BITS).o			:= n
+
+OBJECT_FILES_NON_STANDARD_head_$(BITS).o		:= y
+OBJECT_FILES_NON_STANDARD_relocate_kernel_$(BITS).o	:= y
+OBJECT_FILES_NON_STANDARD_mcount_$(BITS).o		:= y
+OBJECT_FILES_NON_STANDARD_test_nx.o			:= y
 
 CFLAGS_irq.o := -I$(src)/../include/asm/trace
 
diff --git a/arch/x86/platform/efi/Makefile b/arch/x86/platform/efi/Makefile
index 2846aaa..066619b 100644
--- a/arch/x86/platform/efi/Makefile
+++ b/arch/x86/platform/efi/Makefile
@@ -1,3 +1,5 @@
+OBJECT_FILES_NON_STANDARD_efi_thunk_$(BITS).o := y
+
 obj-$(CONFIG_EFI) 		+= quirks.o efi.o efi_$(BITS).o efi_stub_$(BITS).o
 obj-$(CONFIG_ACPI_BGRT) += efi-bgrt.o
 obj-$(CONFIG_EARLY_PRINTK_EFI)	+= early_printk.o
diff --git a/arch/x86/realmode/Makefile b/arch/x86/realmode/Makefile
index e02c2c6..682c895 100644
--- a/arch/x86/realmode/Makefile
+++ b/arch/x86/realmode/Makefile
@@ -6,7 +6,9 @@
 # for more details.
 #
 #
-KASAN_SANITIZE := n
+KASAN_SANITIZE			:= n
+OBJECT_FILES_NON_STANDARD	:= y
+
 subdir- := rm
 
 obj-y += init.o
diff --git a/arch/x86/realmode/rm/Makefile b/arch/x86/realmode/rm/Makefile
index 3e75fcf..053abe7b0 100644
--- a/arch/x86/realmode/rm/Makefile
+++ b/arch/x86/realmode/rm/Makefile
@@ -6,7 +6,8 @@
 # for more details.
 #
 #
-KASAN_SANITIZE := n
+KASAN_SANITIZE			:= n
+OBJECT_FILES_NON_STANDARD	:= y
 
 always := realmode.bin realmode.relocs
 
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index aaf9c0b..68fa977 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -23,6 +23,7 @@ KBUILD_CFLAGS			:= $(cflags-y) -DDISABLE_BRANCH_PROFILING \
 GCOV_PROFILE			:= n
 KASAN_SANITIZE			:= n
 UBSAN_SANITIZE			:= n
+OBJECT_FILES_NON_STANDARD	:= y
 
 lib-y				:= efi-stub-helper.o
 
-- 
2.4.3