From bf76f73c5f6554df1bd337aea5b3ea561f09632c Mon Sep 17 00:00:00 2001
From: Daniel Axtens <dja@axtens.net>
Date: Wed, 20 Jan 2016 15:00:58 -0800
Subject: [PATCH] powerpc: enable UBSAN support

This hooks up UBSAN support for PowerPC.

So far it's found some interesting cases where we don't properly sanitise
input to shifts, including one in our futex handling.  Nothing critical,
but interesting and worth fixing.

[valentinrothberg@gmail.com: arch/powerpc/Kconfig: fix typo in select statement]
Signed-off-by: Daniel Axtens <dja@axtens.net>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 arch/powerpc/Kconfig                | 1 +
 arch/powerpc/kernel/Makefile        | 8 +++++++-
 arch/powerpc/kernel/vdso32/Makefile | 1 +
 arch/powerpc/kernel/vdso64/Makefile | 1 +
 arch/powerpc/xmon/Makefile          | 1 +
 5 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 94f6c5089e0cc..8310be4ffe312 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -158,6 +158,7 @@ config PPC
 	select ARCH_HAS_DMA_SET_COHERENT_MASK
 	select ARCH_HAS_DEVMEM_IS_ALLOWED
 	select HAVE_ARCH_SECCOMP_FILTER
+	select ARCH_HAS_UBSAN_SANITIZE_ALL
 
 config GENERIC_CSUM
 	def_bool CPU_LITTLE_ENDIAN
diff --git a/arch/powerpc/kernel/Makefile b/arch/powerpc/kernel/Makefile
index ba336930d4487..794f22adf99d4 100644
--- a/arch/powerpc/kernel/Makefile
+++ b/arch/powerpc/kernel/Makefile
@@ -136,12 +136,18 @@ endif
 obj-$(CONFIG_EPAPR_PARAVIRT)	+= epapr_paravirt.o epapr_hcalls.o
 obj-$(CONFIG_KVM_GUEST)		+= kvm.o kvm_emul.o
 
-# Disable GCOV in odd or sensitive code
+# Disable GCOV & sanitizers in odd or sensitive code
 GCOV_PROFILE_prom_init.o := n
+UBSAN_SANITIZE_prom_init.o := n
 GCOV_PROFILE_ftrace.o := n
+UBSAN_SANITIZE_ftrace.o := n
 GCOV_PROFILE_machine_kexec_64.o := n
+UBSAN_SANITIZE_machine_kexec_64.o := n
 GCOV_PROFILE_machine_kexec_32.o := n
+UBSAN_SANITIZE_machine_kexec_32.o := n
 GCOV_PROFILE_kprobes.o := n
+UBSAN_SANITIZE_kprobes.o := n
+UBSAN_SANITIZE_vdso.o := n
 
 extra-$(CONFIG_PPC_FPU)		+= fpu.o
 extra-$(CONFIG_ALTIVEC)		+= vector.o
diff --git a/arch/powerpc/kernel/vdso32/Makefile b/arch/powerpc/kernel/vdso32/Makefile
index 6abffb7a8cd98..cbabd143acae8 100644
--- a/arch/powerpc/kernel/vdso32/Makefile
+++ b/arch/powerpc/kernel/vdso32/Makefile
@@ -15,6 +15,7 @@ targets := $(obj-vdso32) vdso32.so vdso32.so.dbg
 obj-vdso32 := $(addprefix $(obj)/, $(obj-vdso32))
 
 GCOV_PROFILE := n
+UBSAN_SANITIZE := n
 
 ccflags-y := -shared -fno-common -fno-builtin
 ccflags-y += -nostdlib -Wl,-soname=linux-vdso32.so.1 \
diff --git a/arch/powerpc/kernel/vdso64/Makefile b/arch/powerpc/kernel/vdso64/Makefile
index 8c8f2ae439356..c710802b8fb68 100644
--- a/arch/powerpc/kernel/vdso64/Makefile
+++ b/arch/powerpc/kernel/vdso64/Makefile
@@ -8,6 +8,7 @@ targets := $(obj-vdso64) vdso64.so vdso64.so.dbg
 obj-vdso64 := $(addprefix $(obj)/, $(obj-vdso64))
 
 GCOV_PROFILE := n
+UBSAN_SANITIZE := n
 
 ccflags-y := -shared -fno-common -fno-builtin
 ccflags-y += -nostdlib -Wl,-soname=linux-vdso64.so.1 \
diff --git a/arch/powerpc/xmon/Makefile b/arch/powerpc/xmon/Makefile
index 1278788d96e3e..436062dbb6e2e 100644
--- a/arch/powerpc/xmon/Makefile
+++ b/arch/powerpc/xmon/Makefile
@@ -3,6 +3,7 @@
 subdir-ccflags-$(CONFIG_PPC_WERROR) := -Werror
 
 GCOV_PROFILE := n
+UBSAN_SANITIZE := n
 
 ccflags-$(CONFIG_PPC64) := $(NO_MINIMAL_TOC)
 
-- 
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