diff options
| -rw-r--r-- | arch/x86/boot/compressed/pagetable.c | 3 | ||||
| -rw-r--r-- | arch/x86/include/asm/kaslr.h | 2 | ||||
| -rw-r--r-- | arch/x86/include/asm/page_64_types.h | 11 | ||||
| -rw-r--r-- | arch/x86/kernel/head_64.S | 2 | ||||
| -rw-r--r-- | arch/x86/mm/kaslr.c | 18 |
5 files changed, 31 insertions, 5 deletions
diff --git a/arch/x86/boot/compressed/pagetable.c b/arch/x86/boot/compressed/pagetable.c index 6e31a6a..56589d0 100644 --- a/arch/x86/boot/compressed/pagetable.c +++ b/arch/x86/boot/compressed/pagetable.c @@ -20,6 +20,9 @@ /* These actually do the work of building the kernel identity maps. */ #include <asm/init.h> #include <asm/pgtable.h> +/* Use the static base for this part of the boot process */ +#undef __PAGE_OFFSET +#define __PAGE_OFFSET __PAGE_OFFSET_BASE #include "../../mm/ident_map.c" /* Used by pgtable.h asm code to force instruction serialization. */ diff --git a/arch/x86/include/asm/kaslr.h b/arch/x86/include/asm/kaslr.h index 683c9d7..62b1b81 100644 --- a/arch/x86/include/asm/kaslr.h +++ b/arch/x86/include/asm/kaslr.h @@ -4,6 +4,8 @@ unsigned long kaslr_get_random_long(const char *purpose); #ifdef CONFIG_RANDOMIZE_MEMORY +extern unsigned long page_offset_base; + void kernel_randomize_memory(void); #else static inline void kernel_randomize_memory(void) { } diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h index d5c2f8b..9215e05 100644 --- a/arch/x86/include/asm/page_64_types.h +++ b/arch/x86/include/asm/page_64_types.h @@ -1,6 +1,10 @@ #ifndef _ASM_X86_PAGE_64_DEFS_H #define _ASM_X86_PAGE_64_DEFS_H +#ifndef __ASSEMBLY__ +#include <asm/kaslr.h> +#endif + #ifdef CONFIG_KASAN #define KASAN_STACK_ORDER 1 #else @@ -32,7 +36,12 @@ * hypervisor to fit. Choosing 16 slots here is arbitrary, but it's * what Xen requires. */ -#define __PAGE_OFFSET _AC(0xffff880000000000, UL) +#define __PAGE_OFFSET_BASE _AC(0xffff880000000000, UL) +#ifdef CONFIG_RANDOMIZE_MEMORY +#define __PAGE_OFFSET page_offset_base +#else +#define __PAGE_OFFSET __PAGE_OFFSET_BASE +#endif /* CONFIG_RANDOMIZE_MEMORY */ #define __START_KERNEL_map _AC(0xffffffff80000000, UL) diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S index c7920ba..9f8efc9 100644 --- a/arch/x86/kernel/head_64.S +++ b/arch/x86/kernel/head_64.S @@ -38,7 +38,7 @@ #define pud_index(x) (((x) >> PUD_SHIFT) & (PTRS_PER_PUD-1)) -L4_PAGE_OFFSET = pgd_index(__PAGE_OFFSET) +L4_PAGE_OFFSET = pgd_index(__PAGE_OFFSET_BASE) L4_START_KERNEL = pgd_index(__START_KERNEL_map) L3_START_KERNEL = pud_index(__START_KERNEL_map) diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index d5380a4..609ecf2 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -43,8 +43,12 @@ * before. You also need to add a BUILD_BUG_ON in kernel_randomize_memory to * ensure that this order is correct and won't be changed. */ -static const unsigned long vaddr_start; -static const unsigned long vaddr_end; +static const unsigned long vaddr_start = __PAGE_OFFSET_BASE; +static const unsigned long vaddr_end = VMALLOC_START; + +/* Default values */ +unsigned long page_offset_base = __PAGE_OFFSET_BASE; +EXPORT_SYMBOL(page_offset_base); /* * Memory regions randomized by KASLR (except modules that use a separate logic @@ -55,6 +59,7 @@ static __initdata struct kaslr_memory_region { unsigned long *base; unsigned long size_tb; } kaslr_regions[] = { + { &page_offset_base, 64/* Maximum */ }, }; /* Get size in bytes used by the memory region */ @@ -77,13 +82,20 @@ void __init kernel_randomize_memory(void) { size_t i; unsigned long vaddr = vaddr_start; - unsigned long rand; + unsigned long rand, memory_tb; struct rnd_state rand_state; unsigned long remain_entropy; if (!kaslr_memory_enabled()) return; + BUG_ON(kaslr_regions[0].base != &page_offset_base); + memory_tb = ((max_pfn << PAGE_SHIFT) >> TB_SHIFT); + + /* Adapt phyiscal memory region size based on available memory */ + if (memory_tb < kaslr_regions[0].size_tb) + kaslr_regions[0].size_tb = memory_tb; + /* Calculate entropy available between regions */ remain_entropy = vaddr_end - vaddr_start; for (i = 0; i < ARRAY_SIZE(kaslr_regions); i++) |