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 8/9] x86/mm: Enable KASLR for vmemmap memory region (x86_64) Date: Tue, 21 Jun 2016 17:47:05 -0700 [thread overview] Message-ID: <1466556426-32664-9-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 vmemmap in the list of randomized memory regions. The vmemmap region holds a representation of the physical memory (through a struct page array). An attacker could use this region to disclose the kernel memory layout (walking the page linked list). Signed-off-by: Thomas Garnier <thgarnie@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> --- arch/x86/include/asm/kaslr.h | 1 + arch/x86/include/asm/pgtable_64_types.h | 4 +++- arch/x86/mm/kaslr.c | 24 +++++++++++++++++++++++- 3 files changed, 27 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/kaslr.h b/arch/x86/include/asm/kaslr.h index 2674ee3de748..1052a797d71d 100644 --- a/arch/x86/include/asm/kaslr.h +++ b/arch/x86/include/asm/kaslr.h @@ -6,6 +6,7 @@ unsigned long kaslr_get_random_long(const char *purpose); #ifdef CONFIG_RANDOMIZE_MEMORY extern unsigned long page_offset_base; extern unsigned long vmalloc_base; +extern unsigned long vmemmap_base; void kernel_randomize_memory(void); #else diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index 6fdef9eef2d5..3a264200c62f 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -57,11 +57,13 @@ typedef struct { pteval_t pte; } pte_t; #define MAXMEM _AC(__AC(1, UL) << MAX_PHYSMEM_BITS, UL) #define VMALLOC_SIZE_TB _AC(32, UL) #define __VMALLOC_BASE _AC(0xffffc90000000000, UL) -#define VMEMMAP_START _AC(0xffffea0000000000, UL) +#define __VMEMMAP_BASE _AC(0xffffea0000000000, UL) #ifdef CONFIG_RANDOMIZE_MEMORY #define VMALLOC_START vmalloc_base +#define VMEMMAP_START vmemmap_base #else #define VMALLOC_START __VMALLOC_BASE +#define VMEMMAP_START __VMEMMAP_BASE #endif /* CONFIG_RANDOMIZE_MEMORY */ #define VMALLOC_END (VMALLOC_START + _AC((VMALLOC_SIZE_TB << 40) - 1, UL)) #define MODULES_VADDR (__START_KERNEL_map + KERNEL_IMAGE_SIZE) diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index c939cfe1b516..4f91dc273062 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -44,13 +44,22 @@ * ensure that this order is correct and won't be changed. */ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE; -static const unsigned long vaddr_end = VMEMMAP_START; + +#if defined(CONFIG_X86_ESPFIX64) +static const unsigned long vaddr_end = ESPFIX_BASE_ADDR; +#elif defined(CONFIG_EFI) +static const unsigned long vaddr_end = EFI_VA_START; +#else +static const unsigned long vaddr_end = __START_KERNEL_map; +#endif /* Default values */ unsigned long page_offset_base = __PAGE_OFFSET_BASE; EXPORT_SYMBOL(page_offset_base); unsigned long vmalloc_base = __VMALLOC_BASE; EXPORT_SYMBOL(vmalloc_base); +unsigned long vmemmap_base = __VMEMMAP_BASE; +EXPORT_SYMBOL(vmemmap_base); /* * Memory regions randomized by KASLR (except modules that use a separate logic @@ -63,6 +72,7 @@ static __initdata struct kaslr_memory_region { } kaslr_regions[] = { { &page_offset_base, 64/* Maximum */ }, { &vmalloc_base, VMALLOC_SIZE_TB }, + { &vmemmap_base, 1 }, }; /* Get size in bytes used by the memory region */ @@ -89,6 +99,18 @@ void __init kernel_randomize_memory(void) struct rnd_state rand_state; unsigned long remain_entropy; + /* + * All these BUILD_BUG_ON checks ensures the memory layout is + * consistent with the vaddr_start/vaddr_end variables. + */ + BUILD_BUG_ON(vaddr_start >= vaddr_end); + BUILD_BUG_ON(config_enabled(CONFIG_X86_ESPFIX64) && + vaddr_end >= EFI_VA_START); + BUILD_BUG_ON((config_enabled(CONFIG_X86_ESPFIX64) || + config_enabled(CONFIG_EFI)) && + vaddr_end >= __START_KERNEL_map); + BUILD_BUG_ON(vaddr_end > __START_KERNEL_map); + if (!kaslr_memory_enabled()) return; -- 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 8/9] x86/mm: Enable KASLR for vmemmap memory region (x86_64) Date: Tue, 21 Jun 2016 17:47:05 -0700 [thread overview] Message-ID: <1466556426-32664-9-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 vmemmap in the list of randomized memory regions. The vmemmap region holds a representation of the physical memory (through a struct page array). An attacker could use this region to disclose the kernel memory layout (walking the page linked list). Signed-off-by: Thomas Garnier <thgarnie@google.com> Signed-off-by: Kees Cook <keescook@chromium.org> --- arch/x86/include/asm/kaslr.h | 1 + arch/x86/include/asm/pgtable_64_types.h | 4 +++- arch/x86/mm/kaslr.c | 24 +++++++++++++++++++++++- 3 files changed, 27 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/kaslr.h b/arch/x86/include/asm/kaslr.h index 2674ee3de748..1052a797d71d 100644 --- a/arch/x86/include/asm/kaslr.h +++ b/arch/x86/include/asm/kaslr.h @@ -6,6 +6,7 @@ unsigned long kaslr_get_random_long(const char *purpose); #ifdef CONFIG_RANDOMIZE_MEMORY extern unsigned long page_offset_base; extern unsigned long vmalloc_base; +extern unsigned long vmemmap_base; void kernel_randomize_memory(void); #else diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h index 6fdef9eef2d5..3a264200c62f 100644 --- a/arch/x86/include/asm/pgtable_64_types.h +++ b/arch/x86/include/asm/pgtable_64_types.h @@ -57,11 +57,13 @@ typedef struct { pteval_t pte; } pte_t; #define MAXMEM _AC(__AC(1, UL) << MAX_PHYSMEM_BITS, UL) #define VMALLOC_SIZE_TB _AC(32, UL) #define __VMALLOC_BASE _AC(0xffffc90000000000, UL) -#define VMEMMAP_START _AC(0xffffea0000000000, UL) +#define __VMEMMAP_BASE _AC(0xffffea0000000000, UL) #ifdef CONFIG_RANDOMIZE_MEMORY #define VMALLOC_START vmalloc_base +#define VMEMMAP_START vmemmap_base #else #define VMALLOC_START __VMALLOC_BASE +#define VMEMMAP_START __VMEMMAP_BASE #endif /* CONFIG_RANDOMIZE_MEMORY */ #define VMALLOC_END (VMALLOC_START + _AC((VMALLOC_SIZE_TB << 40) - 1, UL)) #define MODULES_VADDR (__START_KERNEL_map + KERNEL_IMAGE_SIZE) diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index c939cfe1b516..4f91dc273062 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -44,13 +44,22 @@ * ensure that this order is correct and won't be changed. */ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE; -static const unsigned long vaddr_end = VMEMMAP_START; + +#if defined(CONFIG_X86_ESPFIX64) +static const unsigned long vaddr_end = ESPFIX_BASE_ADDR; +#elif defined(CONFIG_EFI) +static const unsigned long vaddr_end = EFI_VA_START; +#else +static const unsigned long vaddr_end = __START_KERNEL_map; +#endif /* Default values */ unsigned long page_offset_base = __PAGE_OFFSET_BASE; EXPORT_SYMBOL(page_offset_base); unsigned long vmalloc_base = __VMALLOC_BASE; EXPORT_SYMBOL(vmalloc_base); +unsigned long vmemmap_base = __VMEMMAP_BASE; +EXPORT_SYMBOL(vmemmap_base); /* * Memory regions randomized by KASLR (except modules that use a separate logic @@ -63,6 +72,7 @@ static __initdata struct kaslr_memory_region { } kaslr_regions[] = { { &page_offset_base, 64/* Maximum */ }, { &vmalloc_base, VMALLOC_SIZE_TB }, + { &vmemmap_base, 1 }, }; /* Get size in bytes used by the memory region */ @@ -89,6 +99,18 @@ void __init kernel_randomize_memory(void) struct rnd_state rand_state; unsigned long remain_entropy; + /* + * All these BUILD_BUG_ON checks ensures the memory layout is + * consistent with the vaddr_start/vaddr_end variables. + */ + BUILD_BUG_ON(vaddr_start >= vaddr_end); + BUILD_BUG_ON(config_enabled(CONFIG_X86_ESPFIX64) && + vaddr_end >= EFI_VA_START); + BUILD_BUG_ON((config_enabled(CONFIG_X86_ESPFIX64) || + config_enabled(CONFIG_EFI)) && + vaddr_end >= __START_KERNEL_map); + BUILD_BUG_ON(vaddr_end > __START_KERNEL_map); + if (!kaslr_memory_enabled()) return; -- 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 ` Kees Cook [this message] 2016-06-22 0:47 ` [kernel-hardening] [PATCH v7 8/9] x86/mm: Enable KASLR for vmemmap memory region (x86_64) Kees Cook 2016-06-22 0:47 ` [PATCH v7 9/9] x86/mm: Memory hotplug support for KASLR memory randomization (x86_64) Kees Cook 2016-06-22 0:47 ` [kernel-hardening] " 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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