| # SPDX-License-Identifier: GPL-2.0-only |
| config HAVE_ARCH_KMSAN |
| bool |
| |
| config HAVE_KMSAN_COMPILER |
| # Clang versions <14.0.0 also support -fsanitize=kernel-memory, but not |
| # all the features necessary to build the kernel with KMSAN. |
| depends on CC_IS_CLANG && CLANG_VERSION >= 140000 |
| def_bool $(cc-option,-fsanitize=kernel-memory -mllvm -msan-disable-checks=1) |
| |
| config KMSAN |
| bool "KMSAN: detector of uninitialized values use" |
| depends on HAVE_ARCH_KMSAN && HAVE_KMSAN_COMPILER |
| depends on SLUB && DEBUG_KERNEL && !KASAN && !KCSAN |
| select STACKDEPOT |
| select STACKDEPOT_ALWAYS_INIT |
| help |
| KernelMemorySanitizer (KMSAN) is a dynamic detector of uses of |
| uninitialized values in the kernel. It is based on compiler |
| instrumentation provided by Clang and thus requires Clang to build. |
| |
| An important note is that KMSAN is not intended for production use, |
| because it drastically increases kernel memory footprint and slows |
| the whole system down. |
| |
| See <file:Documentation/dev-tools/kmsan.rst> for more details. |
| |
| if KMSAN |
| |
| config HAVE_KMSAN_PARAM_RETVAL |
| # -fsanitize-memory-param-retval is supported only by Clang >= 14. |
| depends on HAVE_KMSAN_COMPILER |
| def_bool $(cc-option,-fsanitize=kernel-memory -fsanitize-memory-param-retval) |
| |
| config KMSAN_CHECK_PARAM_RETVAL |
| bool "Check for uninitialized values passed to and returned from functions" |
| default y |
| depends on HAVE_KMSAN_PARAM_RETVAL |
| help |
| If the compiler supports -fsanitize-memory-param-retval, KMSAN will |
| eagerly check every function parameter passed by value and every |
| function return value. |
| |
| Disabling KMSAN_CHECK_PARAM_RETVAL will result in tracking shadow for |
| function parameters and return values across function borders. This |
| is a more relaxed mode, but it generates more instrumentation code and |
| may potentially report errors in corner cases when non-instrumented |
| functions call instrumented ones. |
| |
| config KMSAN_KUNIT_TEST |
| tristate "KMSAN integration test suite" if !KUNIT_ALL_TESTS |
| default KUNIT_ALL_TESTS |
| depends on TRACEPOINTS && KUNIT |
| help |
| Test suite for KMSAN, testing various error detection scenarios, |
| and checking that reports are correctly output to console. |
| |
| Say Y here if you want the test to be built into the kernel and run |
| during boot; say M if you want the test to build as a module; say N |
| if you are unsure. |
| |
| endif |
