From 5f3da8c08508df82823566c32f753071c8ad36af Mon Sep 17 00:00:00 2001
From: Josh Poimboeuf <jpoimboe@redhat.com>
Date: Tue, 19 Apr 2022 09:05:09 -0700
Subject: [PATCH] objtool: Add CONFIG_HAVE_UACCESS_VALIDATION
Allow an arch specify that it has objtool uaccess validation with
CONFIG_HAVE_UACCESS_VALIDATION. For now, doing so unconditionally
selects CONFIG_OBJTOOL.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/d393d5e2fe73aec6e8e41d5c24f4b6fe8583f2d8.1650384225.git.jpoimboe@redhat.com
---
arch/Kconfig | 4 ++++
arch/x86/Kconfig | 1 +
scripts/Makefile.build | 2 +-
scripts/link-vmlinux.sh | 4 +++-
4 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/arch/Kconfig b/arch/Kconfig
index 904ed51736d4f..cb2954027d102 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1050,6 +1050,10 @@ config HAVE_NOINSTR_HACK
config HAVE_NOINSTR_VALIDATION
bool
+config HAVE_UACCESS_VALIDATION
+ bool
+ select OBJTOOL
+
config HAVE_STACK_VALIDATION
bool
help
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index cf531fbcd2295..5f41f3c3df9a2 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -258,6 +258,7 @@ config X86
select HAVE_PREEMPT_DYNAMIC_CALL
select HAVE_RSEQ
select HAVE_SYSCALL_TRACEPOINTS
+ select HAVE_UACCESS_VALIDATION if HAVE_OBJTOOL
select HAVE_UNSTABLE_SCHED_CLOCK
select HAVE_USER_RETURN_NOTIFIER
select HAVE_GENERIC_VDSO
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 06400504150b3..6a663b27b2868 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -218,7 +218,7 @@ objtool_args = \
$(if $(CONFIG_SLS), --sls) \
$(if $(CONFIG_STACK_VALIDATION), --stackval) \
$(if $(CONFIG_HAVE_STATIC_CALL_INLINE), --static-call) \
- --uaccess \
+ $(if $(CONFIG_HAVE_UACCESS_VALIDATION), --uaccess) \
$(if $(linked-object), --link) \
$(if $(part-of-module), --module) \
$(if $(CONFIG_GCOV_KERNEL), --no-unreachable)
diff --git a/scripts/link-vmlinux.sh b/scripts/link-vmlinux.sh
index a7f6196c7e411..fd578c3809193 100755
--- a/scripts/link-vmlinux.sh
+++ b/scripts/link-vmlinux.sh
@@ -134,7 +134,9 @@ objtool_link()
objtoolopt="${objtoolopt} --static-call"
fi
- objtoolopt="${objtoolopt} --uaccess"
+ if is_enabled CONFIG_HAVE_UACCESS_VALIDATION; then
+ objtoolopt="${objtoolopt} --uaccess"
+ fi
fi
if is_enabled CONFIG_NOINSTR_VALIDATION; then
--
2.30.2