1config HAVE_ARCH_KASAN 2 bool 3 4if HAVE_ARCH_KASAN 5 6config KASAN 7 bool "KASan: runtime memory debugger" 8 depends on SLUB_DEBUG 9 select CONSTRUCTORS 10 help 11 Enables kernel address sanitizer - runtime memory debugger, 12 designed to find out-of-bounds accesses and use-after-free bugs. 13 This is strictly a debugging feature and it requires a gcc version 14 of 4.9.2 or later. Detection of out of bounds accesses to stack or 15 global variables requires gcc 5.0 or later. 16 This feature consumes about 1/8 of available memory and brings about 17 ~x3 performance slowdown. 18 For better error detection enable CONFIG_STACKTRACE, 19 and add slub_debug=U to boot cmdline. 20 21choice 22 prompt "Instrumentation type" 23 depends on KASAN 24 default KASAN_OUTLINE 25 26config KASAN_OUTLINE 27 bool "Outline instrumentation" 28 help 29 Before every memory access compiler insert function call 30 __asan_load*/__asan_store*. These functions performs check 31 of shadow memory. This is slower than inline instrumentation, 32 however it doesn't bloat size of kernel's .text section so 33 much as inline does. 34 35config KASAN_INLINE 36 bool "Inline instrumentation" 37 help 38 Compiler directly inserts code checking shadow memory before 39 memory accesses. This is faster than outline (in some workloads 40 it gives about x2 boost over outline instrumentation), but 41 make kernel's .text size much bigger. 42 This requires a gcc version of 5.0 or later. 43 44endchoice 45 46config TEST_KASAN 47 tristate "Module for testing kasan for bug detection" 48 depends on m && KASAN 49 help 50 This is a test module doing various nasty things like 51 out of bounds accesses, use after free. It is useful for testing 52 kernel debugging features like kernel address sanitizer. 53 54endif 55