diff options
Diffstat (limited to 'arch/arm64')
-rw-r--r-- | arch/arm64/Kconfig | 1 | ||||
-rw-r--r-- | arch/arm64/Makefile | 7 | ||||
-rw-r--r-- | arch/arm64/include/asm/kasan.h | 36 | ||||
-rw-r--r-- | arch/arm64/include/asm/pgtable.h | 7 | ||||
-rw-r--r-- | arch/arm64/include/asm/string.h | 16 | ||||
-rw-r--r-- | arch/arm64/kernel/Makefile | 2 | ||||
-rw-r--r-- | arch/arm64/kernel/arm64ksyms.c | 3 | ||||
-rw-r--r-- | arch/arm64/kernel/head.S | 3 | ||||
-rw-r--r-- | arch/arm64/kernel/image.h | 6 | ||||
-rw-r--r-- | arch/arm64/kernel/module.c | 16 | ||||
-rw-r--r-- | arch/arm64/kernel/setup.c | 4 | ||||
-rw-r--r-- | arch/arm64/lib/memcpy.S | 3 | ||||
-rw-r--r-- | arch/arm64/lib/memmove.S | 7 | ||||
-rw-r--r-- | arch/arm64/lib/memset.S | 3 | ||||
-rw-r--r-- | arch/arm64/mm/Makefile | 3 | ||||
-rw-r--r-- | arch/arm64/mm/kasan_init.c | 165 |
16 files changed, 277 insertions, 5 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1b35bdbd5d74..2782c1189208 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -48,6 +48,7 @@ config ARM64 select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_BITREVERSE select HAVE_ARCH_JUMP_LABEL + select HAVE_ARCH_KASAN if SPARSEMEM_VMEMMAP select HAVE_ARCH_KGDB select HAVE_ARCH_SECCOMP_FILTER select HAVE_ARCH_TRACEHOOK diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile index f9914d7c1bb0..f41c6761ec36 100644 --- a/arch/arm64/Makefile +++ b/arch/arm64/Makefile @@ -55,6 +55,13 @@ else TEXT_OFFSET := 0x00080000 endif +# KASAN_SHADOW_OFFSET = VA_START + (1 << (VA_BITS - 3)) - (1 << 61) +# in 32-bit arithmetic +KASAN_SHADOW_OFFSET := $(shell printf "0x%08x00000000\n" $$(( \ + (0xffffffff & (-1 << ($(CONFIG_ARM64_VA_BITS) - 32))) \ + + (1 << ($(CONFIG_ARM64_VA_BITS) - 32 - 3)) \ + - (1 << (64 - 32 - 3)) )) ) + export TEXT_OFFSET GZFLAGS core-y += arch/arm64/kernel/ arch/arm64/mm/ diff --git a/arch/arm64/include/asm/kasan.h b/arch/arm64/include/asm/kasan.h new file mode 100644 index 000000000000..71dfe14acdca --- /dev/null +++ b/arch/arm64/include/asm/kasan.h @@ -0,0 +1,36 @@ +#ifndef __ASM_KASAN_H +#define __ASM_KASAN_H + +#ifndef __ASSEMBLY__ + +#ifdef CONFIG_KASAN + +#include <asm/memory.h> + +/* + * KASAN_SHADOW_START: beginning of the kernel virtual addresses. + * KASAN_SHADOW_END: KASAN_SHADOW_START + 1/8 of kernel virtual addresses. + */ +#define KASAN_SHADOW_START (VA_START) +#define KASAN_SHADOW_END (KASAN_SHADOW_START + (1UL << (VA_BITS - 3))) + +/* + * This value is used to map an address to the corresponding shadow + * address by the following formula: + * shadow_addr = (address >> 3) + KASAN_SHADOW_OFFSET; + * + * (1 << 61) shadow addresses - [KASAN_SHADOW_OFFSET,KASAN_SHADOW_END] + * cover all 64-bits of virtual addresses. So KASAN_SHADOW_OFFSET + * should satisfy the following equation: + * KASAN_SHADOW_OFFSET = KASAN_SHADOW_END - (1ULL << 61) + */ +#define KASAN_SHADOW_OFFSET (KASAN_SHADOW_END - (1ULL << (64 - 3))) + +void kasan_init(void); + +#else +static inline void kasan_init(void) { } +#endif + +#endif +#endif diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 3f481ef42c07..e3b515fbf0c2 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -41,7 +41,14 @@ * fixed mappings and modules */ #define VMEMMAP_SIZE ALIGN((1UL << (VA_BITS - PAGE_SHIFT)) * sizeof(struct page), PUD_SIZE) + +#ifndef CONFIG_KASAN #define VMALLOC_START (VA_START) +#else +#include <asm/kasan.h> +#define VMALLOC_START (KASAN_SHADOW_END + SZ_64K) +#endif + #define VMALLOC_END (PAGE_OFFSET - PUD_SIZE - VMEMMAP_SIZE - SZ_64K) #define vmemmap ((struct page *)(VMALLOC_END + SZ_64K)) diff --git a/arch/arm64/include/asm/string.h b/arch/arm64/include/asm/string.h index 64d2d4884a9d..2eb714c4639f 100644 --- a/arch/arm64/include/asm/string.h +++ b/arch/arm64/include/asm/string.h @@ -36,17 +36,33 @@ extern __kernel_size_t strnlen(const char *, __kernel_size_t); #define __HAVE_ARCH_MEMCPY extern void *memcpy(void *, const void *, __kernel_size_t); +extern void *__memcpy(void *, const void *, __kernel_size_t); #define __HAVE_ARCH_MEMMOVE extern void *memmove(void *, const void *, __kernel_size_t); +extern void *__memmove(void *, const void *, __kernel_size_t); #define __HAVE_ARCH_MEMCHR extern void *memchr(const void *, int, __kernel_size_t); #define __HAVE_ARCH_MEMSET extern void *memset(void *, int, __kernel_size_t); +extern void *__memset(void *, int, __kernel_size_t); #define __HAVE_ARCH_MEMCMP extern int memcmp(const void *, const void *, size_t); + +#if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__) + +/* + * For files that are not instrumented (e.g. mm/slub.c) we + * should use not instrumented version of mem* functions. + */ + +#define memcpy(dst, src, len) __memcpy(dst, src, len) +#define memmove(dst, src, len) __memmove(dst, src, len) +#define memset(s, c, n) __memset(s, c, n) +#endif + #endif diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 7b17f6245f1e..1b6bda2ff102 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -7,6 +7,8 @@ AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET) CFLAGS_efi-stub.o := -DTEXT_OFFSET=$(TEXT_OFFSET) CFLAGS_armv8_deprecated.o := -I$(src) +KASAN_SANITIZE_efi-stub.o := n + CFLAGS_REMOVE_ftrace.o = -pg CFLAGS_REMOVE_insn.o = -pg CFLAGS_REMOVE_return_address.o = -pg diff --git a/arch/arm64/kernel/arm64ksyms.c b/arch/arm64/kernel/arm64ksyms.c index a85843ddbde8..3b6d8cc9dfe0 100644 --- a/arch/arm64/kernel/arm64ksyms.c +++ b/arch/arm64/kernel/arm64ksyms.c @@ -51,6 +51,9 @@ EXPORT_SYMBOL(strnlen); EXPORT_SYMBOL(memset); EXPORT_SYMBOL(memcpy); EXPORT_SYMBOL(memmove); +EXPORT_SYMBOL(__memset); +EXPORT_SYMBOL(__memcpy); +EXPORT_SYMBOL(__memmove); EXPORT_SYMBOL(memchr); EXPORT_SYMBOL(memcmp); diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index 28a81e948df9..2a8c1d5b3fae 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -444,6 +444,9 @@ __mmap_switched: str_l x21, __fdt_pointer, x5 // Save FDT pointer str_l x24, memstart_addr, x6 // Save PHYS_OFFSET mov x29, #0 +#ifdef CONFIG_KASAN + bl kasan_early_init +#endif b start_kernel ENDPROC(__mmap_switched) diff --git a/arch/arm64/kernel/image.h b/arch/arm64/kernel/image.h index e083af0dd546..6eb8fee93321 100644 --- a/arch/arm64/kernel/image.h +++ b/arch/arm64/kernel/image.h @@ -80,6 +80,12 @@ __efistub_strcmp = __pi_strcmp; __efistub_strncmp = __pi_strncmp; __efistub___flush_dcache_area = __pi___flush_dcache_area; +#ifdef CONFIG_KASAN +__efistub___memcpy = __pi_memcpy; +__efistub___memmove = __pi_memmove; +__efistub___memset = __pi_memset; +#endif + __efistub__text = _text; __efistub__end = _end; __efistub__edata = _edata; diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c index 876eb8df50bf..f4bc779e62e8 100644 --- a/arch/arm64/kernel/module.c +++ b/arch/arm64/kernel/module.c @@ -21,6 +21,7 @@ #include <linux/bitops.h> #include <linux/elf.h> #include <linux/gfp.h> +#include <linux/kasan.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/moduleloader.h> @@ -34,9 +35,18 @@ void *module_alloc(unsigned long size) { - return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END, - GFP_KERNEL, PAGE_KERNEL_EXEC, 0, - NUMA_NO_NODE, __builtin_return_address(0)); + void *p; + + p = __vmalloc_node_range(size, MODULE_ALIGN, MODULES_VADDR, MODULES_END, + GFP_KERNEL, PAGE_KERNEL_EXEC, 0, + NUMA_NO_NODE, __builtin_return_address(0)); + + if (p && (kasan_module_alloc(p, size) < 0)) { + vfree(p); + return NULL; + } + + return p; } enum aarch64_reloc_op { diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c index 6bab21f84a9f..79df79a2ea61 100644 --- a/arch/arm64/kernel/setup.c +++ b/arch/arm64/kernel/setup.c @@ -54,6 +54,7 @@ #include <asm/elf.h> #include <asm/cpufeature.h> #include <asm/cpu_ops.h> +#include <asm/kasan.h> #include <asm/sections.h> #include <asm/setup.h> #include <asm/smp_plat.h> @@ -434,6 +435,9 @@ void __init setup_arch(char **cmdline_p) paging_init(); relocate_initrd(); + + kasan_init(); + request_standard_resources(); early_ioremap_reset(); diff --git a/arch/arm64/lib/memcpy.S b/arch/arm64/lib/memcpy.S index 36a6a62cf263..67613937711f 100644 --- a/arch/arm64/lib/memcpy.S +++ b/arch/arm64/lib/memcpy.S @@ -68,7 +68,10 @@ stp \ptr, \regB, [\regC], \val .endm + .weak memcpy +ENTRY(__memcpy) ENTRY(memcpy) #include "copy_template.S" ret ENDPIPROC(memcpy) +ENDPROC(__memcpy) diff --git a/arch/arm64/lib/memmove.S b/arch/arm64/lib/memmove.S index 68e2f2035e23..a5a4459013b1 100644 --- a/arch/arm64/lib/memmove.S +++ b/arch/arm64/lib/memmove.S @@ -57,12 +57,14 @@ C_h .req x12 D_l .req x13 D_h .req x14 + .weak memmove +ENTRY(__memmove) ENTRY(memmove) cmp dstin, src - b.lo memcpy + b.lo __memcpy add tmp1, src, count cmp dstin, tmp1 - b.hs memcpy /* No overlap. */ + b.hs __memcpy /* No overlap. */ add dst, dstin, count add src, src, count @@ -195,3 +197,4 @@ ENTRY(memmove) b.ne .Ltail63 ret ENDPIPROC(memmove) +ENDPROC(__memmove) diff --git a/arch/arm64/lib/memset.S b/arch/arm64/lib/memset.S index 29f405f08792..f2670a9f218c 100644 --- a/arch/arm64/lib/memset.S +++ b/arch/arm64/lib/memset.S @@ -54,6 +54,8 @@ dst .req x8 tmp3w .req w9 tmp3 .req x9 + .weak memset +ENTRY(__memset) ENTRY(memset) mov dst, dstin /* Preserve return value. */ and A_lw, val, #255 @@ -214,3 +216,4 @@ ENTRY(memset) b.ne .Ltail_maybe_long ret ENDPIPROC(memset) +ENDPROC(__memset) diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile index 773d37a14039..57f57fde5722 100644 --- a/arch/arm64/mm/Makefile +++ b/arch/arm64/mm/Makefile @@ -4,3 +4,6 @@ obj-y := dma-mapping.o extable.o fault.o init.o \ context.o proc.o pageattr.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o obj-$(CONFIG_ARM64_PTDUMP) += dump.o + +obj-$(CONFIG_KASAN) += kasan_init.o +KASAN_SANITIZE_kasan_init.o := n diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c new file mode 100644 index 000000000000..b6a92f5dd568 --- /dev/null +++ b/arch/arm64/mm/kasan_init.c @@ -0,0 +1,165 @@ +/* + * This file contains kasan initialization code for ARM64. + * + * Copyright (c) 2015 Samsung Electronics Co., Ltd. + * Author: Andrey Ryabinin <ryabinin.a.a@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#define pr_fmt(fmt) "kasan: " fmt +#include <linux/kasan.h> +#include <linux/kernel.h> +#include <linux/memblock.h> +#include <linux/start_kernel.h> + +#include <asm/page.h> +#include <asm/pgalloc.h> +#include <asm/pgtable.h> +#include <asm/tlbflush.h> + +static pgd_t tmp_pg_dir[PTRS_PER_PGD] __initdata __aligned(PGD_SIZE); + +static void __init kasan_early_pte_populate(pmd_t *pmd, unsigned long addr, + unsigned long end) +{ + pte_t *pte; + unsigned long next; + + if (pmd_none(*pmd)) + pmd_populate_kernel(&init_mm, pmd, kasan_zero_pte); + + pte = pte_offset_kernel(pmd, addr); + do { + next = addr + PAGE_SIZE; + set_pte(pte, pfn_pte(virt_to_pfn(kasan_zero_page), + PAGE_KERNEL)); + } while (pte++, addr = next, addr != end && pte_none(*pte)); +} + +static void __init kasan_early_pmd_populate(pud_t *pud, + unsigned long addr, + unsigned long end) +{ + pmd_t *pmd; + unsigned long next; + + if (pud_none(*pud)) + pud_populate(&init_mm, pud, kasan_zero_pmd); + + pmd = pmd_offset(pud, addr); + do { + next = pmd_addr_end(addr, end); + kasan_early_pte_populate(pmd, addr, next); + } while (pmd++, addr = next, addr != end && pmd_none(*pmd)); +} + +static void __init kasan_early_pud_populate(pgd_t *pgd, + unsigned long addr, + unsigned long end) +{ + pud_t *pud; + unsigned long next; + + if (pgd_none(*pgd)) + pgd_populate(&init_mm, pgd, kasan_zero_pud); + + pud = pud_offset(pgd, addr); + do { + next = pud_addr_end(addr, end); + kasan_early_pmd_populate(pud, addr, next); + } while (pud++, addr = next, addr != end && pud_none(*pud)); +} + +static void __init kasan_map_early_shadow(void) +{ + unsigned long addr = KASAN_SHADOW_START; + unsigned long end = KASAN_SHADOW_END; + unsigned long next; + pgd_t *pgd; + + pgd = pgd_offset_k(addr); + do { + next = pgd_addr_end(addr, end); + kasan_early_pud_populate(pgd, addr, next); + } while (pgd++, addr = next, addr != end); +} + +void __init kasan_early_init(void) +{ + BUILD_BUG_ON(KASAN_SHADOW_OFFSET != KASAN_SHADOW_END - (1UL << 61)); + BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, PGDIR_SIZE)); + BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PGDIR_SIZE)); + kasan_map_early_shadow(); +} + +static void __init clear_pgds(unsigned long start, + unsigned long end) +{ + /* + * Remove references to kasan page tables from + * swapper_pg_dir. pgd_clear() can't be used + * here because it's nop on 2,3-level pagetable setups + */ + for (; start < end; start += PGDIR_SIZE) + set_pgd(pgd_offset_k(start), __pgd(0)); +} + +static void __init cpu_set_ttbr1(unsigned long ttbr1) +{ + asm( + " msr ttbr1_el1, %0\n" + " isb" + : + : "r" (ttbr1)); +} + +void __init kasan_init(void) +{ + struct memblock_region *reg; + + /* + * We are going to perform proper setup of shadow memory. + * At first we should unmap early shadow (clear_pgds() call bellow). + * However, instrumented code couldn't execute without shadow memory. + * tmp_pg_dir used to keep early shadow mapped until full shadow + * setup will be finished. + */ + memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(tmp_pg_dir)); + cpu_set_ttbr1(__pa(tmp_pg_dir)); + flush_tlb_all(); + + clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END); + + kasan_populate_zero_shadow((void *)KASAN_SHADOW_START, + kasan_mem_to_shadow((void *)MODULES_VADDR)); + + for_each_memblock(memory, reg) { + void *start = (void *)__phys_to_virt(reg->base); + void *end = (void *)__phys_to_virt(reg->base + reg->size); + + if (start >= end) + break; + + /* + * end + 1 here is intentional. We check several shadow bytes in + * advance to slightly speed up fastpath. In some rare cases + * we could cross boundary of mapped shadow, so we just map + * some more here. + */ + vmemmap_populate((unsigned long)kasan_mem_to_shadow(start), + (unsigned long)kasan_mem_to_shadow(end) + 1, + pfn_to_nid(virt_to_pfn(start))); + } + + memset(kasan_zero_page, 0, PAGE_SIZE); + cpu_set_ttbr1(__pa(swapper_pg_dir)); + flush_tlb_all(); + + /* At this point kasan is fully initialized. Enable error messages */ + init_task.kasan_depth = 0; + pr_info("KernelAddressSanitizer initialized\n"); +} |