[deliverable/linux.git] / lib / Kconfig.kasan

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.

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
Commit	Line	Data
	1	config HAVE_ARCH_KASAN
	2	bool
	3
	4	if HAVE_ARCH_KASAN
	5
	6	config 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
	20	choice
	21	prompt "Instrumentation type"
	22	depends on KASAN
	23	default KASAN_OUTLINE
	24
	25	config 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
	34	config 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
	43	endchoice
	44
	45	config 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
	53	endif