From: Kees Cook <keescook@chromium.org> To: Ingo Molnar <mingo@kernel.org> Cc: Kees Cook <keescook@chromium.org>, Thomas Garnier <thgarnie@google.com>, Andy Lutomirski <luto@kernel.org>, x86@kernel.org, Borislav Petkov <bp@suse.de>, Baoquan He <bhe@redhat.com>, Yinghai Lu <yinghai@kernel.org>, Juergen Gross <jgross@suse.com>, Matt Fleming <matt@codeblueprint.co.uk>, Toshi Kani <toshi.kani@hpe.com>, Andrew Morton <akpm@linux-foundation.org>, Dan Williams <dan.j.williams@intel.com>, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, Dave Hansen <dave.hansen@linux.intel.com>, Xiao Guangrong <guangrong.xiao@linux.intel.com>, Martin Schwidefsky <schwidefsky@de.ibm.com>, "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>, Alexander Kuleshov <kuleshovmail@gmail.com>, Alexander Popov <alpopov@ptsecurity.com>, Dave Young <dyoung@redhat.com>, Joerg Roedel <jroedel@suse.de>, Lv Zheng <lv.zheng@intel.com>, Mark Salter <msalter@redhat.com>, Dmitry Vyukov <dvyukov@google.com>, Stephen Smalley <sds@tycho.nsa.gov>, Boris Ostrovsky <boris.ostrovsky@oracle.com>, Christian Borntraeger <borntraeger@de.ibm.com>, Jan Beulich <JBeulich@suse.com>, linux-kernel@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>, linux-doc@vger.kernel.org, kernel-hardening@lists.openwall.com Subject: [PATCH v7 9/9] x86/mm: Memory hotplug support for KASLR memory randomization (x86_64) Date: Tue, 21 Jun 2016 17:47:06 -0700 [thread overview] Message-ID: <1466556426-32664-10-git-send-email-keescook@chromium.org> (raw) In-Reply-To: <1466556426-32664-1-git-send-email-keescook@chromium.org> From: Thomas Garnier <thgarnie@google.com> Add a new option (CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING) to define the padding used for the physical memory mapping section when KASLR memory is enabled. It ensures there is enough virtual address space when CONFIG_MEMORY_HOTPLUG is used. The default value is 10 terabytes. If CONFIG_MEMORY_HOTPLUG is not used, no space is reserved increasing the entropy available. Signed-off-by: Thomas Garnier <thgarnie@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> --- arch/x86/Kconfig | 15 +++++++++++++++ arch/x86/mm/kaslr.c | 7 ++++++- 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index adab3fef3bb4..214b3fadbc11 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2010,6 +2010,21 @@ config RANDOMIZE_MEMORY If unsure, say N. +config RANDOMIZE_MEMORY_PHYSICAL_PADDING + hex "Physical memory mapping padding" if EXPERT + depends on RANDOMIZE_MEMORY + default "0xa" if MEMORY_HOTPLUG + default "0x0" + range 0x1 0x40 if MEMORY_HOTPLUG + range 0x0 0x40 + ---help--- + Define the padding in terabytes added to the existing physical + memory size during kernel memory randomization. It is useful + for memory hotplug support but reduces the entropy available for + address randomization. + + If unsure, leave at the default value. + config HOTPLUG_CPU bool "Support for hot-pluggable CPUs" depends on SMP diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 4f91dc273062..3e9875f7fdda 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -114,8 +114,13 @@ void __init kernel_randomize_memory(void) if (!kaslr_memory_enabled()) return; + /* + * Update Physical memory mapping to available and + * add padding if needed (especially for memory hotplug support). + */ BUG_ON(kaslr_regions[0].base != &page_offset_base); - memory_tb = ((max_pfn << PAGE_SHIFT) >> TB_SHIFT); + memory_tb = ((max_pfn << PAGE_SHIFT) >> TB_SHIFT) + + CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING; /* Adapt phyiscal memory region size based on available memory */ if (memory_tb < kaslr_regions[0].size_tb) -- 2.7.4
WARNING: multiple messages have this Message-ID (diff)
From: Kees Cook <keescook@chromium.org> To: Ingo Molnar <mingo@kernel.org> Cc: Kees Cook <keescook@chromium.org>, Thomas Garnier <thgarnie@google.com>, Andy Lutomirski <luto@kernel.org>, x86@kernel.org, Borislav Petkov <bp@suse.de>, Baoquan He <bhe@redhat.com>, Yinghai Lu <yinghai@kernel.org>, Juergen Gross <jgross@suse.com>, Matt Fleming <matt@codeblueprint.co.uk>, Toshi Kani <toshi.kani@hpe.com>, Andrew Morton <akpm@linux-foundation.org>, Dan Williams <dan.j.williams@intel.com>, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, Dave Hansen <dave.hansen@linux.intel.com>, Xiao Guangrong <guangrong.xiao@linux.intel.com>, Martin Schwidefsky <schwidefsky@de.ibm.com>, "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>, Alexander Kuleshov <kuleshovmail@gmail.com>, Alexander Popov <alpopov@ptsecurity.com>, Dave Young <dyoung@redhat.com>, Joerg Roedel <jroedel@suse.de>, Lv Zheng <lv.zheng@intel.com>, Mark Salter <msalter@redhat.com>, Dmitry Vyukov <dvyukov@google.com>, Stephen Smalley <sds@tycho.nsa.gov>, Boris Ostrovsky <boris.ostrovsky@oracle.com>, Christian Borntraeger <borntraeger@de.ibm.com>, Jan Beulich <JBeulich@suse.com>, linux-kernel@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>, linux-doc@vger.kernel.org, kernel-hardening@lists.openwall.com Subject: [kernel-hardening] [PATCH v7 9/9] x86/mm: Memory hotplug support for KASLR memory randomization (x86_64) Date: Tue, 21 Jun 2016 17:47:06 -0700 [thread overview] Message-ID: <1466556426-32664-10-git-send-email-keescook@chromium.org> (raw) In-Reply-To: <1466556426-32664-1-git-send-email-keescook@chromium.org> From: Thomas Garnier <thgarnie@google.com> Add a new option (CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING) to define the padding used for the physical memory mapping section when KASLR memory is enabled. It ensures there is enough virtual address space when CONFIG_MEMORY_HOTPLUG is used. The default value is 10 terabytes. If CONFIG_MEMORY_HOTPLUG is not used, no space is reserved increasing the entropy available. Signed-off-by: Thomas Garnier <thgarnie@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> --- arch/x86/Kconfig | 15 +++++++++++++++ arch/x86/mm/kaslr.c | 7 ++++++- 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index adab3fef3bb4..214b3fadbc11 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2010,6 +2010,21 @@ config RANDOMIZE_MEMORY If unsure, say N. +config RANDOMIZE_MEMORY_PHYSICAL_PADDING + hex "Physical memory mapping padding" if EXPERT + depends on RANDOMIZE_MEMORY + default "0xa" if MEMORY_HOTPLUG + default "0x0" + range 0x1 0x40 if MEMORY_HOTPLUG + range 0x0 0x40 + ---help--- + Define the padding in terabytes added to the existing physical + memory size during kernel memory randomization. It is useful + for memory hotplug support but reduces the entropy available for + address randomization. + + If unsure, leave at the default value. + config HOTPLUG_CPU bool "Support for hot-pluggable CPUs" depends on SMP diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 4f91dc273062..3e9875f7fdda 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -114,8 +114,13 @@ void __init kernel_randomize_memory(void) if (!kaslr_memory_enabled()) return; + /* + * Update Physical memory mapping to available and + * add padding if needed (especially for memory hotplug support). + */ BUG_ON(kaslr_regions[0].base != &page_offset_base); - memory_tb = ((max_pfn << PAGE_SHIFT) >> TB_SHIFT); + memory_tb = ((max_pfn << PAGE_SHIFT) >> TB_SHIFT) + + CONFIG_RANDOMIZE_MEMORY_PHYSICAL_PADDING; /* Adapt phyiscal memory region size based on available memory */ if (memory_tb < kaslr_regions[0].size_tb) -- 2.7.4
next prev parent reply other threads:[~2016-06-22 0:47 UTC|newest] Thread overview: 74+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-06-22 0:46 [PATCH v7 0/9] x86/mm: memory area address KASLR Kees Cook 2016-06-22 0:46 ` [kernel-hardening] " Kees Cook 2016-06-22 0:46 ` [PATCH v7 1/9] x86/mm: Refactor KASLR entropy functions Kees Cook 2016-06-22 0:46 ` [kernel-hardening] " Kees Cook 2016-07-08 20:33 ` [tip:x86/boot] " tip-bot for Thomas Garnier 2016-06-22 0:46 ` [PATCH v7 2/9] x86/mm: Update physical mapping variable names (x86_64) Kees Cook 2016-06-22 0:46 ` [kernel-hardening] " Kees Cook 2016-07-08 20:34 ` [tip:x86/boot] x86/mm: Update physical mapping variable names tip-bot for Thomas Garnier 2016-06-22 0:47 ` [PATCH v7 3/9] x86/mm: PUD VA support for physical mapping (x86_64) Kees Cook 2016-06-22 0:47 ` [kernel-hardening] " Kees Cook 2016-07-08 20:34 ` [tip:x86/boot] x86/mm: Add PUD VA support for physical mapping tip-bot for Thomas Garnier 2016-06-22 0:47 ` [PATCH v7 4/9] x86/mm: Separate variable for trampoline PGD (x86_64) Kees Cook 2016-06-22 0:47 ` [kernel-hardening] " Kees Cook 2016-07-08 20:35 ` [tip:x86/boot] x86/mm: Separate variable for trampoline PGD tip-bot for Thomas Garnier 2016-06-22 0:47 ` [PATCH v7 5/9] x86/mm: Implement ASLR for kernel memory regions (x86_64) Kees Cook 2016-06-22 0:47 ` [kernel-hardening] " Kees Cook 2016-07-08 20:35 ` [tip:x86/boot] x86/mm: Implement ASLR for kernel memory regions tip-bot for Thomas Garnier 2016-06-22 0:47 ` [PATCH v7 6/9] x86/mm: Enable KASLR for physical mapping memory region (x86_64) Kees Cook 2016-06-22 0:47 ` [kernel-hardening] " Kees Cook 2016-07-08 20:35 ` [tip:x86/boot] x86/mm: Enable KASLR for physical mapping memory regions tip-bot for Thomas Garnier 2016-08-14 4:25 ` Brian Gerst 2016-08-14 23:26 ` Baoquan He 2016-08-16 11:31 ` Brian Gerst 2016-08-16 13:42 ` Borislav Petkov 2016-08-16 13:49 ` Borislav Petkov 2016-08-16 15:54 ` Borislav Petkov 2016-08-16 17:50 ` Borislav Petkov 2016-08-16 19:49 ` Kees Cook 2016-08-16 21:01 ` Borislav Petkov 2016-08-17 0:31 ` Brian Gerst 2016-08-17 9:11 ` Borislav Petkov 2016-08-17 10:19 ` Ingo Molnar 2016-08-17 11:33 ` Borislav Petkov 2016-08-18 10:49 ` [tip:x86/urgent] x86/microcode/AMD: Fix initrd loading with CONFIG_RANDOMIZE_MEMORY=y tip-bot for Borislav Petkov 2016-06-22 0:47 ` [PATCH v7 7/9] x86/mm: Enable KASLR for vmalloc memory region (x86_64) Kees Cook 2016-06-22 0:47 ` [kernel-hardening] " Kees Cook 2016-07-08 20:36 ` [tip:x86/boot] x86/mm: Enable KASLR for vmalloc memory regions tip-bot for Thomas Garnier 2016-06-22 0:47 ` [PATCH v7 8/9] x86/mm: Enable KASLR for vmemmap memory region (x86_64) Kees Cook 2016-06-22 0:47 ` [kernel-hardening] " Kees Cook 2016-06-22 0:47 ` Kees Cook [this message] 2016-06-22 0:47 ` [kernel-hardening] [PATCH v7 9/9] x86/mm: Memory hotplug support for KASLR memory randomization (x86_64) Kees Cook 2016-07-08 20:36 ` [tip:x86/boot] x86/mm: Add memory hotplug support for KASLR memory randomization tip-bot for Thomas Garnier 2016-06-22 12:47 ` [kernel-hardening] [PATCH v7 0/9] x86/mm: memory area address KASLR Jason Cooper 2016-06-22 15:59 ` Thomas Garnier 2016-06-22 17:05 ` Kees Cook 2016-06-22 17:05 ` Kees Cook 2016-06-23 19:33 ` Jason Cooper 2016-06-23 19:33 ` Jason Cooper 2016-06-23 19:45 ` Sandy Harris 2016-06-23 19:59 ` Kees Cook 2016-06-23 19:59 ` Kees Cook 2016-06-23 20:19 ` Jason Cooper 2016-06-23 20:16 ` Jason Cooper 2016-06-23 19:58 ` Kees Cook 2016-06-23 19:58 ` Kees Cook 2016-06-23 20:05 ` Ard Biesheuvel 2016-06-23 20:05 ` Ard Biesheuvel 2016-06-24 1:11 ` Jason Cooper 2016-06-24 1:11 ` Jason Cooper 2016-06-24 10:54 ` Ard Biesheuvel 2016-06-24 10:54 ` Ard Biesheuvel 2016-06-24 16:02 ` devicetree random-seed properties, was: "Re: [PATCH v7 0/9] x86/mm: memory area address KASLR" Jason Cooper 2016-06-24 16:02 ` [kernel-hardening] " Jason Cooper 2016-06-24 19:04 ` Kees Cook 2016-06-24 19:04 ` [kernel-hardening] " Kees Cook 2016-06-24 20:40 ` Andy Lutomirski 2016-06-24 20:40 ` [kernel-hardening] " Andy Lutomirski 2016-06-30 21:48 ` Jason Cooper 2016-06-30 21:48 ` [kernel-hardening] " Jason Cooper 2016-06-30 21:56 ` Thomas Garnier 2016-06-30 21:48 ` Jason Cooper 2016-06-30 21:48 ` [kernel-hardening] " Jason Cooper 2016-07-07 22:24 ` [PATCH v7 0/9] x86/mm: memory area address KASLR Kees Cook 2016-07-07 22:24 ` [kernel-hardening] " Kees Cook
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