arm64: mm: use ARCH_HAS_DEBUG_WX instead of arch defined

Extract DEBUG_WX to mm/Kconfig.debug for shared use.  Change to use
ARCH_HAS_DEBUG_WX instead of DEBUG_WX defined by arch port.

Signed-off-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/e19709e7576f65e303245fe520cad5f7bae72763.1587455584.git.zong.li@sifive.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Zong Li 2020-06-03 16:04:02 -07:00 committed by Linus Torvalds
parent 7e01ccb43d
commit 09587a09ad
2 changed files with 1 additions and 29 deletions

View file

@ -9,6 +9,7 @@ config ARM64
select ACPI_MCFG if (ACPI && PCI)
select ACPI_SPCR_TABLE if ACPI
select ACPI_PPTT if ACPI
select ARCH_HAS_DEBUG_WX
select ARCH_BINFMT_ELF_STATE
select ARCH_HAS_DEBUG_VIRTUAL
select ARCH_HAS_DEVMEM_IS_ALLOWED

View file

@ -23,35 +23,6 @@ config ARM64_RANDOMIZE_TEXT_OFFSET
of TEXT_OFFSET and platforms must not require a specific
value.
config DEBUG_WX
bool "Warn on W+X mappings at boot"
select PTDUMP_CORE
---help---
Generate a warning if any W+X mappings are found at boot.
This is useful for discovering cases where the kernel is leaving
W+X mappings after applying NX, as such mappings are a security risk.
This check also includes UXN, which should be set on all kernel
mappings.
Look for a message in dmesg output like this:
arm64/mm: Checked W+X mappings: passed, no W+X pages found.
or like this, if the check failed:
arm64/mm: Checked W+X mappings: FAILED, <N> W+X pages found.
Note that even if the check fails, your kernel is possibly
still fine, as W+X mappings are not a security hole in
themselves, what they do is that they make the exploitation
of other unfixed kernel bugs easier.
There is no runtime or memory usage effect of this option
once the kernel has booted up - it's a one time check.
If in doubt, say "Y".
config DEBUG_EFI
depends on EFI && DEBUG_INFO
bool "UEFI debugging"