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 debugging feature. It consumes about 1/8 14 of available memory and brings about ~x3 performance slowdown. 15 For better error detection enable CONFIG_STACKTRACE, 16 and add slub_debug=U to boot cmdline. 17 18config KASAN_SHADOW_OFFSET 19 hex 20 default 0xdffffc0000000000 if X86_64 21 22choice 23 prompt "Instrumentation type" 24 depends on KASAN 25 default KASAN_OUTLINE 26 27config KASAN_OUTLINE 28 bool "Outline instrumentation" 29 help 30 Before every memory access compiler insert function call 31 __asan_load*/__asan_store*. These functions performs check 32 of shadow memory. This is slower than inline instrumentation, 33 however it doesn't bloat size of kernel's .text section so 34 much as inline does. 35 36config KASAN_INLINE 37 bool "Inline instrumentation" 38 help 39 Compiler directly inserts code checking shadow memory before 40 memory accesses. This is faster than outline (in some workloads 41 it gives about x2 boost over outline instrumentation), but 42 make kernel's .text size much bigger. 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