diff options
| -rw-r--r-- | arch/arm64/Kconfig | 2 | ||||
| -rw-r--r-- | arch/arm64/mm/kasan_init.c | 130 |
2 files changed, 81 insertions, 51 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index ba6aab55d464..a93339f5178f 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -85,7 +85,7 @@ config ARM64 select HAVE_ARCH_BITREVERSE select HAVE_ARCH_HUGE_VMAP select HAVE_ARCH_JUMP_LABEL - select HAVE_ARCH_KASAN if SPARSEMEM_VMEMMAP && !(ARM64_16K_PAGES && ARM64_VA_BITS_48) + select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48) select HAVE_ARCH_KGDB select HAVE_ARCH_MMAP_RND_BITS select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c index 81f03959a4ab..acba49fb5aac 100644 --- a/arch/arm64/mm/kasan_init.c +++ b/arch/arm64/mm/kasan_init.c @@ -11,6 +11,7 @@ */ #define pr_fmt(fmt) "kasan: " fmt +#include <linux/bootmem.h> #include <linux/kasan.h> #include <linux/kernel.h> #include <linux/sched/task.h> @@ -35,77 +36,117 @@ static pgd_t tmp_pg_dir[PTRS_PER_PGD] __initdata __aligned(PGD_SIZE); * with the physical address from __pa_symbol. */ -static void __init kasan_early_pte_populate(pmd_t *pmd, unsigned long addr, - unsigned long end) +static phys_addr_t __init kasan_alloc_zeroed_page(int node) { - pte_t *pte; - unsigned long next; + void *p = memblock_virt_alloc_try_nid(PAGE_SIZE, PAGE_SIZE, + __pa(MAX_DMA_ADDRESS), + MEMBLOCK_ALLOC_ACCESSIBLE, node); + return __pa(p); +} + +static pte_t *__init kasan_pte_offset(pmd_t *pmd, unsigned long addr, int node, + bool early) +{ + if (pmd_none(*pmd)) { + phys_addr_t pte_phys = early ? __pa_symbol(kasan_zero_pte) + : kasan_alloc_zeroed_page(node); + __pmd_populate(pmd, pte_phys, PMD_TYPE_TABLE); + } + + return early ? pte_offset_kimg(pmd, addr) + : pte_offset_kernel(pmd, addr); +} - if (pmd_none(*pmd)) - __pmd_populate(pmd, __pa_symbol(kasan_zero_pte), PMD_TYPE_TABLE); +static pmd_t *__init kasan_pmd_offset(pud_t *pud, unsigned long addr, int node, + bool early) +{ + if (pud_none(*pud)) { + phys_addr_t pmd_phys = early ? __pa_symbol(kasan_zero_pmd) + : kasan_alloc_zeroed_page(node); + __pud_populate(pud, pmd_phys, PMD_TYPE_TABLE); + } + + return early ? pmd_offset_kimg(pud, addr) : pmd_offset(pud, addr); +} + +static pud_t *__init kasan_pud_offset(pgd_t *pgd, unsigned long addr, int node, + bool early) +{ + if (pgd_none(*pgd)) { + phys_addr_t pud_phys = early ? __pa_symbol(kasan_zero_pud) + : kasan_alloc_zeroed_page(node); + __pgd_populate(pgd, pud_phys, PMD_TYPE_TABLE); + } + + return early ? pud_offset_kimg(pgd, addr) : pud_offset(pgd, addr); +} + +static void __init kasan_pte_populate(pmd_t *pmd, unsigned long addr, + unsigned long end, int node, bool early) +{ + unsigned long next; + pte_t *pte = kasan_pte_offset(pmd, addr, node, early); - pte = pte_offset_kimg(pmd, addr); do { + phys_addr_t page_phys = early ? __pa_symbol(kasan_zero_page) + : kasan_alloc_zeroed_page(node); next = addr + PAGE_SIZE; - set_pte(pte, pfn_pte(sym_to_pfn(kasan_zero_page), - PAGE_KERNEL)); + set_pte(pte, pfn_pte(__phys_to_pfn(page_phys), 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) +static void __init kasan_pmd_populate(pud_t *pud, unsigned long addr, + unsigned long end, int node, bool early) { - pmd_t *pmd; unsigned long next; + pmd_t *pmd = kasan_pmd_offset(pud, addr, node, early); - if (pud_none(*pud)) - __pud_populate(pud, __pa_symbol(kasan_zero_pmd), PMD_TYPE_TABLE); - - pmd = pmd_offset_kimg(pud, addr); do { next = pmd_addr_end(addr, end); - kasan_early_pte_populate(pmd, addr, next); + kasan_pte_populate(pmd, addr, next, node, early); } 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) +static void __init kasan_pud_populate(pgd_t *pgd, unsigned long addr, + unsigned long end, int node, bool early) { - pud_t *pud; unsigned long next; + pud_t *pud = kasan_pud_offset(pgd, addr, node, early); - if (pgd_none(*pgd)) - __pgd_populate(pgd, __pa_symbol(kasan_zero_pud), PUD_TYPE_TABLE); - - pud = pud_offset_kimg(pgd, addr); do { next = pud_addr_end(addr, end); - kasan_early_pmd_populate(pud, addr, next); + kasan_pmd_populate(pud, addr, next, node, early); } while (pud++, addr = next, addr != end && pud_none(*pud)); } -static void __init kasan_map_early_shadow(void) +static void __init kasan_pgd_populate(unsigned long addr, unsigned long end, + int node, bool early) { - 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); + kasan_pud_populate(pgd, addr, next, node, early); } while (pgd++, addr = next, addr != end); } +/* The early shadow maps everything to a single page of zeroes */ asmlinkage 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(); + kasan_pgd_populate(KASAN_SHADOW_START, KASAN_SHADOW_END, NUMA_NO_NODE, + true); +} + +/* Set up full kasan mappings, ensuring that the mapped pages are zeroed */ +static void __init kasan_map_populate(unsigned long start, unsigned long end, + int node) +{ + kasan_pgd_populate(start & PAGE_MASK, PAGE_ALIGN(end), node, false); } /* @@ -142,8 +183,8 @@ void __init kasan_init(void) struct memblock_region *reg; int i; - kimg_shadow_start = (u64)kasan_mem_to_shadow(_text); - kimg_shadow_end = (u64)kasan_mem_to_shadow(_end); + kimg_shadow_start = (u64)kasan_mem_to_shadow(_text) & PAGE_MASK; + kimg_shadow_end = PAGE_ALIGN((u64)kasan_mem_to_shadow(_end)); mod_shadow_start = (u64)kasan_mem_to_shadow((void *)MODULES_VADDR); mod_shadow_end = (u64)kasan_mem_to_shadow((void *)MODULES_END); @@ -161,19 +202,8 @@ void __init kasan_init(void) clear_pgds(KASAN_SHADOW_START, KASAN_SHADOW_END); - vmemmap_populate(kimg_shadow_start, kimg_shadow_end, - pfn_to_nid(virt_to_pfn(lm_alias(_text)))); - - /* - * vmemmap_populate() has populated the shadow region that covers the - * kernel image with SWAPPER_BLOCK_SIZE mappings, so we have to round - * the start and end addresses to SWAPPER_BLOCK_SIZE as well, to prevent - * kasan_populate_zero_shadow() from replacing the page table entries - * (PMD or PTE) at the edges of the shadow region for the kernel - * image. - */ - kimg_shadow_start = round_down(kimg_shadow_start, SWAPPER_BLOCK_SIZE); - kimg_shadow_end = round_up(kimg_shadow_end, SWAPPER_BLOCK_SIZE); + kasan_map_populate(kimg_shadow_start, kimg_shadow_end, + pfn_to_nid(virt_to_pfn(lm_alias(_text)))); kasan_populate_zero_shadow((void *)KASAN_SHADOW_START, (void *)mod_shadow_start); @@ -191,9 +221,9 @@ void __init kasan_init(void) if (start >= end) break; - vmemmap_populate((unsigned long)kasan_mem_to_shadow(start), - (unsigned long)kasan_mem_to_shadow(end), - pfn_to_nid(virt_to_pfn(start))); + kasan_map_populate((unsigned long)kasan_mem_to_shadow(start), + (unsigned long)kasan_mem_to_shadow(end), + pfn_to_nid(virt_to_pfn(start))); } /* |