[PATCH 1/2] kasan: Improve and simplify Kconfig.kasan

From: Marco Elver
Date: Mon Jun 29 2020 - 16:57:55 EST


Turn 'KASAN' into a menuconfig, to avoid cluttering its parent menu with
the suboptions if enabled. Use 'if KASAN ... endif' instead of having
to 'depend on KASAN' for each entry.

Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
---
lib/Kconfig.kasan | 15 ++++++++-------
1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
index 34b84bcbd3d9..89053defc0d9 100644
--- a/lib/Kconfig.kasan
+++ b/lib/Kconfig.kasan
@@ -18,7 +18,7 @@ config CC_HAS_KASAN_SW_TAGS
config CC_HAS_WORKING_NOSANITIZE_ADDRESS
def_bool !CC_IS_GCC || GCC_VERSION >= 80300

-config KASAN
+menuconfig KASAN
bool "KASAN: runtime memory debugger"
depends on (HAVE_ARCH_KASAN && CC_HAS_KASAN_GENERIC) || \
(HAVE_ARCH_KASAN_SW_TAGS && CC_HAS_KASAN_SW_TAGS)
@@ -29,9 +29,10 @@ config KASAN
designed to find out-of-bounds accesses and use-after-free bugs.
See Documentation/dev-tools/kasan.rst for details.

+if KASAN
+
choice
prompt "KASAN mode"
- depends on KASAN
default KASAN_GENERIC
help
KASAN has two modes: generic KASAN (similar to userspace ASan,
@@ -88,7 +89,6 @@ endchoice

choice
prompt "Instrumentation type"
- depends on KASAN
default KASAN_OUTLINE

config KASAN_OUTLINE
@@ -113,7 +113,6 @@ endchoice

config KASAN_STACK_ENABLE
bool "Enable stack instrumentation (unsafe)" if CC_IS_CLANG && !COMPILE_TEST
- depends on KASAN
help
The LLVM stack address sanitizer has a know problem that
causes excessive stack usage in a lot of functions, see
@@ -134,7 +133,7 @@ config KASAN_STACK

config KASAN_S390_4_LEVEL_PAGING
bool "KASan: use 4-level paging"
- depends on KASAN && S390
+ depends on S390
help
Compiling the kernel with KASan disables automatic 3-level vs
4-level paging selection. 3-level paging is used by default (up
@@ -151,7 +150,7 @@ config KASAN_SW_TAGS_IDENTIFY

config KASAN_VMALLOC
bool "Back mappings in vmalloc space with real shadow memory"
- depends on KASAN && HAVE_ARCH_KASAN_VMALLOC
+ depends on HAVE_ARCH_KASAN_VMALLOC
help
By default, the shadow region for vmalloc space is the read-only
zero page. This means that KASAN cannot detect errors involving
@@ -164,8 +163,10 @@ config KASAN_VMALLOC

config TEST_KASAN
tristate "Module for testing KASAN for bug detection"
- depends on m && KASAN
+ depends on m
help
This is a test module doing various nasty things like
out of bounds accesses, use after free. It is useful for testing
kernel debugging features like KASAN.
+
+endif # KASAN
--
2.27.0.212.ge8ba1cc988-goog