1config HAVE_ARCH_KASAN 2 bool 3 4if HAVE_ARCH_KASAN 5 6config KASAN 7 bool "KASan: runtime memory debugger" 8 depends on SLUB || (SLAB && !DEBUG_SLAB) 9 select CONSTRUCTORS 10 select STACKDEPOT 11 help 12 Enables kernel address sanitizer - runtime memory debugger, 13 designed to find out-of-bounds accesses and use-after-free bugs. 14 This is strictly a debugging feature and it requires a gcc version 15 of 4.9.2 or later. Detection of out of bounds accesses to stack or 16 global variables requires gcc 5.0 or later. 17 This feature consumes about 1/8 of available memory and brings about 18 ~x3 performance slowdown. 19 For better error detection enable CONFIG_STACKTRACE. 20 Currently CONFIG_KASAN doesn't work with CONFIG_DEBUG_SLAB 21 (the resulting kernel does not boot). 22 23choice 24 prompt "Instrumentation type" 25 depends on KASAN 26 default KASAN_OUTLINE 27 28config KASAN_OUTLINE 29 bool "Outline instrumentation" 30 help 31 Before every memory access compiler insert function call 32 __asan_load*/__asan_store*. These functions performs check 33 of shadow memory. This is slower than inline instrumentation, 34 however it doesn't bloat size of kernel's .text section so 35 much as inline does. 36 37config KASAN_INLINE 38 bool "Inline instrumentation" 39 help 40 Compiler directly inserts code checking shadow memory before 41 memory accesses. This is faster than outline (in some workloads 42 it gives about x2 boost over outline instrumentation), but 43 make kernel's .text size much bigger. 44 This requires a gcc version of 5.0 or later. 45 46endchoice 47 48config TEST_KASAN 49 tristate "Module for testing kasan for bug detection" 50 depends on m && KASAN 51 help 52 This is a test module doing various nasty things like 53 out of bounds accesses, use after free. It is useful for testing 54 kernel debugging features like kernel address sanitizer. 55 56endif 57