@@ -68,7 +68,7 @@ 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
@@ -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>
@@ -28,66 +29,6 @@
static pgd_t tmp_pg_dir[PTRS_PER_PGD] __initdata __aligned(PGD_SIZE);
-/* Creates mappings for kasan during early boot. The mapped memory is zeroed */
-static int __meminit kasan_map_populate(unsigned long start, unsigned long end,
- int node)
-{
- unsigned long addr, pfn, next;
- unsigned long long size;
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
- int ret;
-
- ret = vmemmap_populate(start, end, node);
- /*
- * We might have partially populated memory, so check for no entries,
- * and zero only those that actually exist.
- */
- for (addr = start; addr < end; addr = next) {
- pgd = pgd_offset_k(addr);
- if (pgd_none(*pgd)) {
- next = pgd_addr_end(addr, end);
- continue;
- }
-
- pud = pud_offset(pgd, addr);
- if (pud_none(*pud)) {
- next = pud_addr_end(addr, end);
- continue;
- }
- if (pud_sect(*pud)) {
- /* This is PUD size page */
- next = pud_addr_end(addr, end);
- size = PUD_SIZE;
- pfn = pud_pfn(*pud);
- } else {
- pmd = pmd_offset(pud, addr);
- if (pmd_none(*pmd)) {
- next = pmd_addr_end(addr, end);
- continue;
- }
- if (pmd_sect(*pmd)) {
- /* This is PMD size page */
- next = pmd_addr_end(addr, end);
- size = PMD_SIZE;
- pfn = pmd_pfn(*pmd);
- } else {
- pte = pte_offset_kernel(pmd, addr);
- next = addr + PAGE_SIZE;
- if (pte_none(*pte))
- continue;
- /* This is base size page */
- size = PAGE_SIZE;
- pfn = pte_pfn(*pte);
- }
- }
- memset(phys_to_virt(PFN_PHYS(pfn)), 0, size);
- }
- return ret;
-}
-
/*
* The p*d_populate functions call virt_to_phys implicitly so they can't be used
* directly on kernel symbols (bm_p*d). All the early functions are called too
@@ -95,77 +36,117 @@ static int __meminit kasan_map_populate(unsigned long start, unsigned long end,
* 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);
+}
- if (pmd_none(*pmd))
- __pmd_populate(pmd, __pa_symbol(kasan_zero_pte), PMD_TYPE_TABLE);
+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);
+}
+
+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);
}
/*
@@ -202,8 +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);
@@ -224,17 +205,6 @@ void __init kasan_init(void)
kasan_map_populate(kimg_shadow_start, kimg_shadow_end,
pfn_to_nid(virt_to_pfn(lm_alias(_text))));
- /*
- * kasan_map_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_populate_zero_shadow((void *)KASAN_SHADOW_START,
(void *)mod_shadow_start);
kasan_populate_zero_shadow((void *)kimg_shadow_end,