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 20choice 21 prompt "Instrumentation type" 22 depends on KASAN 23 default KASAN_OUTLINE 24 25config KASAN_OUTLINE 26 bool "Outline instrumentation" 27 help 28 Before every memory access compiler insert function call 29 __asan_load*/__asan_store*. These functions performs check 30 of shadow memory. This is slower than inline instrumentation, 31 however it doesn't bloat size of kernel's .text section so 32 much as inline does. 33 34config KASAN_INLINE 35 bool "Inline instrumentation" 36 help 37 Compiler directly inserts code checking shadow memory before 38 memory accesses. This is faster than outline (in some workloads 39 it gives about x2 boost over outline instrumentation), but 40 make kernel's .text size much bigger. 41 This requires a gcc version of 5.0 or later. 42 43endchoice 44 45config TEST_KASAN 46 tristate "Module for testing kasan for bug detection" 47 depends on m && KASAN 48 help 49 This is a test module doing various nasty things like 50 out of bounds accesses, use after free. It is useful for testing 51 kernel debugging features like kernel address sanitizer. 52 53endif 54