| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1415121836-16241-1-git-send-email-leif.lindholm@linaro.org> Date: Tue, 4 Nov 2014 17:23:56 +0000 From: Leif Lindholm <leif.lindholm@...aro.org> To: linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org, linuxppc-dev@...ts.ozlabs.org, linux-s390@...r.kernel.org Cc: linux@....linux.org.uk, catalin.marinas@....com, will.deacon@....com, benh@...nel.crashing.org, paulus@...ba.org, mpe@...erman.id.au, schwidefsky@...ibm.com, eiko.carstens@...ibm.com, linux390@...ibm.com, metcalf@...era.com, gxt@...c.pku.edu.cn, tglx@...utronix.de, mingo@...hat.com, hpa@...or.com, x86@...nel.org, arnd@...db.de, gregkh@...uxfoundation.org, keescook@...omium.org, luto@...capital.net, oleg@...hat.com, akpm@...ux-foundation.org, dave.long@...aro.org, hch@...radead.org, arjan@...ux.intel.com Subject: [RFC PATCH] make CONFIG_STRICT_DEVMEM a core non-debug feature Most, but not all, architectures supporting CONFIG_STRICT_DEVMEM treat it as a debug feature - although its function is pretty much the opposite of debug. This patch deletes all architecture-specific config options and moves the option to core code, as a non-debug option. Signed-off-by: Leif Lindholm <leif.lindholm@...aro.org> --- Apologies for wide distribution, but this is a bit invasive, if trivial. arch/Kconfig | 3 +++ arch/arm/Kconfig | 1 + arch/arm/Kconfig.debug | 14 -------------- arch/arm64/Kconfig | 1 + arch/arm64/Kconfig.debug | 14 -------------- arch/powerpc/Kconfig | 1 + arch/powerpc/Kconfig.debug | 12 ------------ arch/s390/Kconfig | 1 + arch/s390/Kconfig.debug | 12 ------------ arch/tile/Kconfig | 4 +--- arch/unicore32/Kconfig | 1 + arch/unicore32/Kconfig.debug | 14 -------------- arch/x86/Kconfig | 1 + arch/x86/Kconfig.debug | 17 ----------------- drivers/char/Kconfig | 16 ++++++++++++++++ 15 files changed, 26 insertions(+), 86 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 05d7a8a..e5f4f03 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -484,6 +484,9 @@ config HAVE_IRQ_EXIT_ON_IRQ_STACK This spares a stack switch and improves cache usage on softirq processing. +config HAVE_ARCH_RESTRICTED_DEVMEM + bool + # # ABI hall of shame # diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 89c4b5c..e04910f 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -30,6 +30,7 @@ config ARM select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT) select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL select HAVE_ARCH_KGDB + select HAVE_ARCH_RESTRICTED_DEVMEM if MMU select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT) select HAVE_ARCH_TRACEHOOK select HAVE_BPF_JIT diff --git a/arch/arm/Kconfig.debug b/arch/arm/Kconfig.debug index d8f6a2e..2a02a7d 100644 --- a/arch/arm/Kconfig.debug +++ b/arch/arm/Kconfig.debug @@ -14,20 +14,6 @@ config ARM_PTDUMP kernel. If in doubt, say "N" -config STRICT_DEVMEM - bool "Filter access to /dev/mem" - depends on MMU - ---help--- - If this option is disabled, you allow userspace (root) access to all - of memory, including kernel and userspace memory. Accidental - access to this is obviously disastrous, but specific access can - be used by people debugging the kernel. - - If this option is switched on, the /dev/mem file only allows - userspace access to memory mapped peripherals. - - If in doubt, say Y. - # RMK wants arm kernels compiled with frame pointers or stack unwinding. # If you know what you are doing and are willing to live without stack # traces, you can get a slightly smaller kernel by setting this option to diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 9532f8d..90abbb2 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -37,6 +37,7 @@ config ARM64 select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_KGDB + select HAVE_ARCH_RESTRICTED_DEVMEM if MMU select HAVE_ARCH_TRACEHOOK select HAVE_BPF_JIT select HAVE_C_RECORDMCOUNT diff --git a/arch/arm64/Kconfig.debug b/arch/arm64/Kconfig.debug index 0a12933..d0036dd 100644 --- a/arch/arm64/Kconfig.debug +++ b/arch/arm64/Kconfig.debug @@ -6,20 +6,6 @@ config FRAME_POINTER bool default y -config STRICT_DEVMEM - bool "Filter access to /dev/mem" - depends on MMU - help - If this option is disabled, you allow userspace (root) access to all - of memory, including kernel and userspace memory. Accidental - access to this is obviously disastrous, but specific access can - be used by people debugging the kernel. - - If this option is switched on, the /dev/mem file only allows - userspace access to memory mapped peripherals. - - If in doubt, say Y. - config PID_IN_CONTEXTIDR bool "Write the current PID to the CONTEXTIDR register" help diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 88eace4..cd35068 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -148,6 +148,7 @@ config PPC select HAVE_ARCH_AUDITSYSCALL select ARCH_SUPPORTS_ATOMIC_RMW select DCACHE_WORD_ACCESS if PPC64 && CPU_LITTLE_ENDIAN + select HAVE_ARCH_RESTRICTED_DEVMEM config GENERIC_CSUM def_bool CPU_LITTLE_ENDIAN diff --git a/arch/powerpc/Kconfig.debug b/arch/powerpc/Kconfig.debug index ec2e40f..6f11382 100644 --- a/arch/powerpc/Kconfig.debug +++ b/arch/powerpc/Kconfig.debug @@ -334,18 +334,6 @@ config PPC_EARLY_DEBUG_CPM_ADDR platform probing is done, all platforms selected must share the same address. -config STRICT_DEVMEM - def_bool y - prompt "Filter access to /dev/mem" - help - This option restricts access to /dev/mem. If this option is - disabled, you allow userspace access to all memory, including - kernel and userspace memory. Accidental memory access is likely - to be disastrous. - Memory access is required for experts who want to debug the kernel. - - If you are unsure, say Y. - config FAIL_IOMMU bool "Fault-injection capability for IOMMU" depends on FAULT_INJECTION diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index f2cf1f9..fe92272 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -109,6 +109,7 @@ config S390 select HAVE_ALIGNED_STRUCT_PAGE if SLUB select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_JUMP_LABEL if !MARCH_G5 + select HAVE_ARCH_RESTRICTED_DEVMEM select HAVE_ARCH_SECCOMP_FILTER select HAVE_ARCH_TRACEHOOK select HAVE_ARCH_TRANSPARENT_HUGEPAGE if 64BIT diff --git a/arch/s390/Kconfig.debug b/arch/s390/Kconfig.debug index c56878e..26c5d5be 100644 --- a/arch/s390/Kconfig.debug +++ b/arch/s390/Kconfig.debug @@ -5,18 +5,6 @@ config TRACE_IRQFLAGS_SUPPORT source "lib/Kconfig.debug" -config STRICT_DEVMEM - def_bool y - prompt "Filter access to /dev/mem" - ---help--- - This option restricts access to /dev/mem. If this option is - disabled, you allow userspace access to all memory, including - kernel and userspace memory. Accidental memory access is likely - to be disastrous. - Memory access is required for experts who want to debug the kernel. - - If you are unsure, say Y. - config S390_PTDUMP bool "Export kernel pagetable layout to userspace via debugfs" depends on DEBUG_KERNEL diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig index 7cca418..f881168 100644 --- a/arch/tile/Kconfig +++ b/arch/tile/Kconfig @@ -27,6 +27,7 @@ config TILE select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE select HAVE_DEBUG_STACKOVERFLOW select ARCH_WANT_FRAME_POINTERS + select HAVE_ARCH_RESTRICTED_DEVMEM # FIXME: investigate whether we need/want these options. # select HAVE_IOREMAP_PROT @@ -110,9 +111,6 @@ config ARCH_DISCONTIGMEM_DEFAULT config TRACE_IRQFLAGS_SUPPORT def_bool y -config STRICT_DEVMEM - def_bool y - # SMP is required for Tilera Linux. config SMP def_bool y diff --git a/arch/unicore32/Kconfig b/arch/unicore32/Kconfig index 928237a..574b07f 100644 --- a/arch/unicore32/Kconfig +++ b/arch/unicore32/Kconfig @@ -18,6 +18,7 @@ config UNICORE32 select ARCH_WANT_FRAME_POINTERS select GENERIC_IOMAP select MODULES_USE_ELF_REL + select HAVE_ARCH_RESTRICTED_DEVMEM if MMU help UniCore-32 is 32-bit Instruction Set Architecture, including a series of low-power-consumption RISC chip diff --git a/arch/unicore32/Kconfig.debug b/arch/unicore32/Kconfig.debug index 1a36262..f075bbe 100644 --- a/arch/unicore32/Kconfig.debug +++ b/arch/unicore32/Kconfig.debug @@ -2,20 +2,6 @@ menu "Kernel hacking" source "lib/Kconfig.debug" -config STRICT_DEVMEM - bool "Filter access to /dev/mem" - depends on MMU - ---help--- - If this option is disabled, you allow userspace (root) access to all - of memory, including kernel and userspace memory. Accidental - access to this is obviously disastrous, but specific access can - be used by people debugging the kernel. - - If this option is switched on, the /dev/mem file only allows - userspace access to memory mapped peripherals. - - If in doubt, say Y. - config EARLY_PRINTK def_bool DEBUG_OCD help diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index ded8a67..91392bf 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -137,6 +137,7 @@ config X86 select HAVE_ACPI_APEI_NMI if ACPI select ACPI_LEGACY_TABLES_LOOKUP if ACPI select X86_FEATURE_NAMES if PROC_FS + select HAVE_ARCH_RESTRICTED_DEVMEM config INSTRUCTION_DECODER def_bool y diff --git a/arch/x86/Kconfig.debug b/arch/x86/Kconfig.debug index 61bd2ad..e35d4a1 100644 --- a/arch/x86/Kconfig.debug +++ b/arch/x86/Kconfig.debug @@ -5,23 +5,6 @@ config TRACE_IRQFLAGS_SUPPORT source "lib/Kconfig.debug" -config STRICT_DEVMEM - bool "Filter access to /dev/mem" - ---help--- - If this option is disabled, you allow userspace (root) access to all - of memory, including kernel and userspace memory. Accidental - access to this is obviously disastrous, but specific access can - be used by people debugging the kernel. Note that with PAT support - enabled, even in this case there are restrictions on /dev/mem - use due to the cache aliasing requirements. - - If this option is switched on, the /dev/mem file only allows - userspace access to PCI space and the BIOS code and data regions. - This is sufficient for dosemu and X and all common users of - /dev/mem. - - If in doubt, say Y. - config X86_VERBOSE_BOOTUP bool "Enable verbose x86 bootup info messages" default y diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig index efefd12..39f7817 100644 --- a/drivers/char/Kconfig +++ b/drivers/char/Kconfig @@ -6,6 +6,22 @@ menu "Character devices" source "drivers/tty/Kconfig" +config STRICT_DEVMEM + bool "Reduced access to /dev/mem" + depends on HAVE_ARCH_RESTRICTED_DEVMEM + default y + help + If this option is disabled, you allow userspace (root) access to all + of memory, including kernel and userspace memory. Accidental + access to this is obviously disastrous, but specific access can + be used by people debugging the kernel. + + If this option is switched on, the /dev/mem file restricts userspace + access to an architecture-specific subset of the physical address + space. + + If in doubt, say Y. + config DEVKMEM bool "/dev/kmem virtual device support" default y -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists