From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: + arm64-mm-use-arch_has_debug_wx-instead-of-arch-defined.patch added to -mm tree Date: Sat, 25 Apr 2020 18:06:12 -0700 Message-ID: <20200426010612.41jaMSYBW%akpm@linux-foundation.org> References: <20200420181310.c18b3c0aa4dc5b3e5ec1be10@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:41350 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725962AbgDZBGO (ORCPT ); Sat, 25 Apr 2020 21:06:14 -0400 In-Reply-To: <20200420181310.c18b3c0aa4dc5b3e5ec1be10@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: bp@alien8.de, catalin.marinas@arm.com, hpa@zytor.com, mingo@redhat.com, mm-commits@vger.kernel.org, palmer@dabbelt.com, paul.walmsley@sifive.com, tglx@linutronix.de, will@kernel.org, zong.li@sifive.com The patch titled Subject: arm64: mm: use ARCH_HAS_DEBUG_WX instead of arch defined has been added to the -mm tree. Its filename is arm64-mm-use-arch_has_debug_wx-instead-of-arch-defined.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/arm64-mm-use-arch_has_debug_wx-instead-of-arch-defined.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/arm64-mm-use-arch_has_debug_wx-instead-of-arch-defined.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Zong Li Subject: 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. Link: http://lkml.kernel.org/r/e19709e7576f65e303245fe520cad5f7bae72763.1587455584.git.zong.li@sifive.com Signed-off-by: Zong Li Cc: Borislav Petkov Cc: Catalin Marinas Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Thomas Gleixner Cc: Will Deacon Signed-off-by: Andrew Morton --- arch/arm64/Kconfig | 1 + arch/arm64/Kconfig.debug | 29 ----------------------------- 2 files changed, 1 insertion(+), 29 deletions(-) --- a/arch/arm64/Kconfig~arm64-mm-use-arch_has_debug_wx-instead-of-arch-defined +++ a/arch/arm64/Kconfig @@ -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_HAS_DEBUG_VIRTUAL select ARCH_HAS_DEVMEM_IS_ALLOWED select ARCH_HAS_DMA_PREP_COHERENT --- a/arch/arm64/Kconfig.debug~arm64-mm-use-arch_has_debug_wx-instead-of-arch-defined +++ a/arch/arm64/Kconfig.debug @@ -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, 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".