604c8e676e
The SET_MODULE_RONX protections are effectively the same as the
DEBUG_RODATA protections we enabled by default back in commit
57efac2f71 ("arm64: enable CONFIG_DEBUG_RODATA by default"). It
seems unusual to have one but not the other.
As evidenced by the help text, the rationale appears to be that
SET_MODULE_RONX interacts poorly with tracing and patching, but both of
these make use of the insn framework, which takes SET_MODULE_RONX into
account. Any remaining issues are bugs which should be fixed regardless
of the default state of the option.
This patch enables DEBUG_SET_MODULE_RONX by default, and replaces the
help text with a new wording derived from the DEBUG_RODATA help text,
which better describes the functionality. Previously, the DEBUG_RODATA
entry was inconsistently indented with spaces, which are replaced with
tabs as with the other Kconfig entries.
Additionally, the wording of recommended defaults is made consistent for
all options. These are placed in a new paragraph, unquoted, as a full
sentence (with a period/full stop) as this appears to be the most common
form per $(git grep 'in doubt').
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Laura Abbott <labbott@fedoraproject.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
78 lines
2.6 KiB
Plaintext
78 lines
2.6 KiB
Plaintext
menu "Kernel hacking"
|
|
|
|
source "lib/Kconfig.debug"
|
|
|
|
config ARM64_PTDUMP
|
|
bool "Export kernel pagetable layout to userspace via debugfs"
|
|
depends on DEBUG_KERNEL
|
|
select DEBUG_FS
|
|
help
|
|
Say Y here if you want to show the kernel pagetable layout in a
|
|
debugfs file. This information is only useful for kernel developers
|
|
who are working in architecture specific areas of the kernel.
|
|
It is probably not a good idea to enable this feature in a production
|
|
kernel.
|
|
|
|
If in doubt, say N.
|
|
|
|
config PID_IN_CONTEXTIDR
|
|
bool "Write the current PID to the CONTEXTIDR register"
|
|
help
|
|
Enabling this option causes the kernel to write the current PID to
|
|
the CONTEXTIDR register, at the expense of some additional
|
|
instructions during context switch. Say Y here only if you are
|
|
planning to use hardware trace tools with this kernel.
|
|
|
|
config ARM64_RANDOMIZE_TEXT_OFFSET
|
|
bool "Randomize TEXT_OFFSET at build time"
|
|
help
|
|
Say Y here if you want the image load offset (AKA TEXT_OFFSET)
|
|
of the kernel to be randomized at build-time. When selected,
|
|
this option will cause TEXT_OFFSET to be randomized upon any
|
|
build of the kernel, and the offset will be reflected in the
|
|
text_offset field of the resulting Image. This can be used to
|
|
fuzz-test bootloaders which respect text_offset.
|
|
|
|
This option is intended for bootloader and/or kernel testing
|
|
only. Bootloaders must make no assumptions regarding the value
|
|
of TEXT_OFFSET and platforms must not require a specific
|
|
value.
|
|
|
|
config DEBUG_SET_MODULE_RONX
|
|
bool "Set loadable kernel module data as NX and text as RO"
|
|
depends on MODULES
|
|
default y
|
|
help
|
|
Is this is set, kernel module text and rodata will be made read-only.
|
|
This is to help catch accidental or malicious attempts to change the
|
|
kernel's executable code.
|
|
|
|
If in doubt, say Y.
|
|
|
|
config DEBUG_RODATA
|
|
bool "Make kernel text and rodata read-only"
|
|
default y
|
|
help
|
|
If this is set, kernel text and rodata will be made read-only. This
|
|
is to help catch accidental or malicious attempts to change the
|
|
kernel's executable code.
|
|
|
|
If in doubt, say Y.
|
|
|
|
config DEBUG_ALIGN_RODATA
|
|
depends on DEBUG_RODATA
|
|
bool "Align linker sections up to SECTION_SIZE"
|
|
help
|
|
If this option is enabled, sections that may potentially be marked as
|
|
read only or non-executable will be aligned up to the section size of
|
|
the kernel. This prevents sections from being split into pages and
|
|
avoids a potential TLB penalty. The downside is an increase in
|
|
alignment and potentially wasted space. Turn on this option if
|
|
performance is more important than memory pressure.
|
|
|
|
If in doubt, say N.
|
|
|
|
source "drivers/hwtracing/coresight/Kconfig"
|
|
|
|
endmenu
|