forked from Minki/linux
757b435aaa
When building with debugging symbols, take the absolute path to the vmlinux binary and add it to the special PE/COFF debug table entry. This allows a debug EFI build to find the vmlinux binary, which is very helpful in debugging, given that the offset where the Image is first loaded by EFI is highly unpredictable. On implementations of UEFI that choose to implement it, this information is exposed via the EFI debug support table, which is a UEFI configuration table that is accessible both by the firmware at boot time and by the OS at runtime, and lists all PE/COFF images loaded by the system. The format of the NB10 Codeview entry is based on the definition used by EDK2, which is our primary reference when it comes to the use of PE/COFF in the context of UEFI firmware. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [will: use realpath instead of shell invocation, as discussed on list] Signed-off-by: Will Deacon <will.deacon@arm.com>
109 lines
3.6 KiB
Plaintext
109 lines
3.6 KiB
Plaintext
menu "Kernel hacking"
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source "lib/Kconfig.debug"
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config ARM64_PTDUMP_CORE
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def_bool n
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config ARM64_PTDUMP_DEBUGFS
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bool "Export kernel pagetable layout to userspace via debugfs"
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depends on DEBUG_KERNEL
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select ARM64_PTDUMP_CORE
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select DEBUG_FS
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help
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Say Y here if you want to show the kernel pagetable layout in a
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debugfs file. This information is only useful for kernel developers
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who are working in architecture specific areas of the kernel.
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It is probably not a good idea to enable this feature in a production
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kernel.
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If in doubt, say N.
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config PID_IN_CONTEXTIDR
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bool "Write the current PID to the CONTEXTIDR register"
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help
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Enabling this option causes the kernel to write the current PID to
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the CONTEXTIDR register, at the expense of some additional
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instructions during context switch. Say Y here only if you are
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planning to use hardware trace tools with this kernel.
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config ARM64_RANDOMIZE_TEXT_OFFSET
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bool "Randomize TEXT_OFFSET at build time"
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help
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Say Y here if you want the image load offset (AKA TEXT_OFFSET)
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of the kernel to be randomized at build-time. When selected,
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this option will cause TEXT_OFFSET to be randomized upon any
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build of the kernel, and the offset will be reflected in the
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text_offset field of the resulting Image. This can be used to
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fuzz-test bootloaders which respect text_offset.
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This option is intended for bootloader and/or kernel testing
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only. Bootloaders must make no assumptions regarding the value
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of TEXT_OFFSET and platforms must not require a specific
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value.
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config DEBUG_WX
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bool "Warn on W+X mappings at boot"
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select ARM64_PTDUMP_CORE
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---help---
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Generate a warning if any W+X mappings are found at boot.
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This is useful for discovering cases where the kernel is leaving
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W+X mappings after applying NX, as such mappings are a security risk.
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This check also includes UXN, which should be set on all kernel
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mappings.
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Look for a message in dmesg output like this:
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arm64/mm: Checked W+X mappings: passed, no W+X pages found.
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or like this, if the check failed:
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arm64/mm: Checked W+X mappings: FAILED, <N> W+X pages found.
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Note that even if the check fails, your kernel is possibly
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still fine, as W+X mappings are not a security hole in
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themselves, what they do is that they make the exploitation
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of other unfixed kernel bugs easier.
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There is no runtime or memory usage effect of this option
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once the kernel has booted up - it's a one time check.
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If in doubt, say "Y".
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config DEBUG_SET_MODULE_RONX
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bool "Set loadable kernel module data as NX and text as RO"
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depends on MODULES
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default y
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help
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Is this is set, kernel module text and rodata will be made read-only.
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This is to help catch accidental or malicious attempts to change the
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kernel's executable code.
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If in doubt, say Y.
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config DEBUG_ALIGN_RODATA
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depends on DEBUG_RODATA
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bool "Align linker sections up to SECTION_SIZE"
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help
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If this option is enabled, sections that may potentially be marked as
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read only or non-executable will be aligned up to the section size of
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the kernel. This prevents sections from being split into pages and
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avoids a potential TLB penalty. The downside is an increase in
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alignment and potentially wasted space. Turn on this option if
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performance is more important than memory pressure.
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If in doubt, say N.
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config DEBUG_EFI
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depends on EFI && DEBUG_INFO
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bool "UEFI debugging"
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help
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Enable this option to include EFI specific debugging features into
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the kernel that are only useful when using a debug build of the
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UEFI firmware
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source "drivers/hwtracing/coresight/Kconfig"
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endmenu
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