linux-imx

# SPDX-License-Identifier: GPL-2.0-only

# This config refers to the generic KASAN mode.

config HAVE_ARCH_KASAN

    bool

​

config HAVE_ARCH_KASAN_SW_TAGS

    bool

​

config CC_HAS_KASAN_GENERIC

    def_bool $(cc-option, -fsanitize=kernel-address)

​

config CC_HAS_KASAN_SW_TAGS

    def_bool $(cc-option, -fsanitize=kernel-hwaddress)

​

config KASAN

    bool "KASAN: runtime memory debugger"

    depends on (HAVE_ARCH_KASAN && CC_HAS_KASAN_GENERIC) || \

           (HAVE_ARCH_KASAN_SW_TAGS && CC_HAS_KASAN_SW_TAGS)

    depends on (SLUB && SYSFS) || (SLAB && !DEBUG_SLAB)

    help

      Enables KASAN (KernelAddressSANitizer) - runtime memory debugger,

      designed to find out-of-bounds accesses and use-after-free bugs.

      See Documentation/dev-tools/kasan.rst for details.

​

choice

    prompt "KASAN mode"

    depends on KASAN

    default KASAN_GENERIC

    help

      KASAN has two modes: generic KASAN (similar to userspace ASan,

      x86_64/arm64/xtensa, enabled with CONFIG_KASAN_GENERIC) and

      software tag-based KASAN (a version based on software memory

      tagging, arm64 only, similar to userspace HWASan, enabled with

      CONFIG_KASAN_SW_TAGS).

      Both generic and tag-based KASAN are strictly debugging features.

​

config KASAN_GENERIC

    bool "Generic mode"

    depends on HAVE_ARCH_KASAN && CC_HAS_KASAN_GENERIC

    depends on (SLUB && SYSFS) || (SLAB && !DEBUG_SLAB)

    select SLUB_DEBUG if SLUB

    select CONSTRUCTORS

    select STACKDEPOT

    help

      Enables generic KASAN mode.

      Supported in both GCC and Clang. With GCC it requires version 4.9.2

      or later for basic support and version 5.0 or later for detection of

      out-of-bounds accesses for stack and global variables and for inline

      instrumentation mode (CONFIG_KASAN_INLINE). With Clang it requires

      version 3.7.0 or later and it doesn't support detection of

      out-of-bounds accesses for global variables yet.

      This mode consumes about 1/8th of available memory at kernel start

      and introduces an overhead of ~x1.5 for the rest of the allocations.

      The performance slowdown is ~x3.

      For better error detection enable CONFIG_STACKTRACE.

      Currently CONFIG_KASAN_GENERIC doesn't work with CONFIG_DEBUG_SLAB

      (the resulting kernel does not boot).

​

config KASAN_SW_TAGS

    bool "Software tag-based mode"

    depends on HAVE_ARCH_KASAN_SW_TAGS && CC_HAS_KASAN_SW_TAGS

    depends on (SLUB && SYSFS) || (SLAB && !DEBUG_SLAB)

    select SLUB_DEBUG if SLUB