Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1# SPDX-License-Identifier: GPL-2.0-only
2config HAVE_GCC_PLUGINS
3 bool
4 help
5 An arch should select this symbol if it supports building with
6 GCC plugins.
7
8menuconfig GCC_PLUGINS
9 bool "GCC plugins"
10 depends on HAVE_GCC_PLUGINS
11 depends on CC_IS_GCC
12 depends on $(success,test -e $(shell,$(CC) -print-file-name=plugin)/include/plugin-version.h)
13 default y
14 help
15 GCC plugins are loadable modules that provide extra features to the
16 compiler. They are useful for runtime instrumentation and static analysis.
17
18 See Documentation/kbuild/gcc-plugins.rst for details.
19
20if GCC_PLUGINS
21
22config GCC_PLUGIN_SANCOV
23 bool
24 # Plugin can be removed once the kernel only supports GCC 6+
25 depends on !CC_HAS_SANCOV_TRACE_PC
26 help
27 This plugin inserts a __sanitizer_cov_trace_pc() call at the start of
28 basic blocks. It supports all gcc versions with plugin support (from
29 gcc-4.5 on). It is based on the commit "Add fuzzing coverage support"
30 by Dmitry Vyukov <dvyukov@google.com>.
31
32config GCC_PLUGIN_LATENT_ENTROPY
33 bool "Generate some entropy during boot and runtime"
34 help
35 By saying Y here the kernel will instrument some kernel code to
36 extract some entropy from both original and artificially created
37 program state. This will help especially embedded systems where
38 there is little 'natural' source of entropy normally. The cost
39 is some slowdown of the boot process (about 0.5%) and fork and
40 irq processing.
41
42 Note that entropy extracted this way is not cryptographically
43 secure!
44
45 This plugin was ported from grsecurity/PaX. More information at:
46 * https://grsecurity.net/
47 * https://pax.grsecurity.net/
48
49config GCC_PLUGIN_RANDSTRUCT
50 bool "Randomize layout of sensitive kernel structures"
51 select MODVERSIONS if MODULES
52 help
53 If you say Y here, the layouts of structures that are entirely
54 function pointers (and have not been manually annotated with
55 __no_randomize_layout), or structures that have been explicitly
56 marked with __randomize_layout, will be randomized at compile-time.
57 This can introduce the requirement of an additional information
58 exposure vulnerability for exploits targeting these structure
59 types.
60
61 Enabling this feature will introduce some performance impact,
62 slightly increase memory usage, and prevent the use of forensic
63 tools like Volatility against the system (unless the kernel
64 source tree isn't cleaned after kernel installation).
65
66 The seed used for compilation is located at
67 scripts/gcc-plugins/randomize_layout_seed.h. It remains after
68 a make clean to allow for external modules to be compiled with
69 the existing seed and will be removed by a make mrproper or
70 make distclean.
71
72 This plugin was ported from grsecurity/PaX. More information at:
73 * https://grsecurity.net/
74 * https://pax.grsecurity.net/
75
76config GCC_PLUGIN_RANDSTRUCT_PERFORMANCE
77 bool "Use cacheline-aware structure randomization"
78 depends on GCC_PLUGIN_RANDSTRUCT
79 depends on !COMPILE_TEST # do not reduce test coverage
80 help
81 If you say Y here, the RANDSTRUCT randomization will make a
82 best effort at restricting randomization to cacheline-sized
83 groups of elements. It will further not randomize bitfields
84 in structures. This reduces the performance hit of RANDSTRUCT
85 at the cost of weakened randomization.
86
87config GCC_PLUGIN_ARM_SSP_PER_TASK
88 bool
89 depends on GCC_PLUGINS && ARM
90
91endif