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Diffstat (limited to 'lib/Kconfig.kasan')
| -rw-r--r-- | lib/Kconfig.kasan | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan new file mode 100644 index 000000000..777eda7d1 --- /dev/null +++ b/lib/Kconfig.kasan @@ -0,0 +1,58 @@ +config HAVE_ARCH_KASAN + bool + +if HAVE_ARCH_KASAN + +config KASAN + bool "KASan: runtime memory debugger" + depends on SLUB_DEBUG + select CONSTRUCTORS + help + Enables kernel address sanitizer - runtime memory debugger, + designed to find out-of-bounds accesses and use-after-free bugs. + This is strictly a debugging feature and it requires a gcc version + of 4.9.2 or later. Detection of out of bounds accesses to stack or + global variables requires gcc 5.0 or later. + This feature consumes about 1/8 of available memory and brings about + ~x3 performance slowdown. + For better error detection enable CONFIG_STACKTRACE, + and add slub_debug=U to boot cmdline. + +config KASAN_SHADOW_OFFSET + hex + default 0xdffffc0000000000 if X86_64 + +choice + prompt "Instrumentation type" + depends on KASAN + default KASAN_OUTLINE + +config KASAN_OUTLINE + bool "Outline instrumentation" + help + Before every memory access compiler insert function call + __asan_load*/__asan_store*. These functions performs check + of shadow memory. This is slower than inline instrumentation, + however it doesn't bloat size of kernel's .text section so + much as inline does. + +config KASAN_INLINE + bool "Inline instrumentation" + help + Compiler directly inserts code checking shadow memory before + memory accesses. This is faster than outline (in some workloads + it gives about x2 boost over outline instrumentation), but + make kernel's .text size much bigger. + This requires a gcc version of 5.0 or later. + +endchoice + +config TEST_KASAN + tristate "Module for testing kasan for bug detection" + depends on m && KASAN + help + This is a test module doing various nasty things like + out of bounds accesses, use after free. It is useful for testing + kernel debugging features like kernel address sanitizer. + +endif |