blob: 5e39dcf23fdbc15e12cedcf6b75a51ccfea6cf9d [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
// Copyright (C) 2019 Andes Technology Corporation
#include <linux/pfn.h>
#include <linux/init_task.h>
#include <linux/kasan.h>
#include <linux/kernel.h>
#include <linux/memblock.h>
#include <linux/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/fixmap.h>
#include <asm/pgalloc.h>
/*
* Kasan shadow region must lie at a fixed address across sv39, sv48 and sv57
* which is right before the kernel.
*
* For sv39, the region is aligned on PGDIR_SIZE so we only need to populate
* the page global directory with kasan_early_shadow_pmd.
*
* For sv48 and sv57, the region start is aligned on PGDIR_SIZE whereas the end
* region is not and then we have to go down to the PUD level.
*/
static pgd_t tmp_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
static p4d_t tmp_p4d[PTRS_PER_P4D] __page_aligned_bss;
static pud_t tmp_pud[PTRS_PER_PUD] __page_aligned_bss;
static void __init kasan_populate_pte(pmd_t *pmd, unsigned long vaddr, unsigned long end)
{
phys_addr_t phys_addr;
pte_t *ptep, *p;
if (pmd_none(*pmd)) {
p = memblock_alloc(PTRS_PER_PTE * sizeof(pte_t), PAGE_SIZE);
set_pmd(pmd, pfn_pmd(PFN_DOWN(__pa(p)), PAGE_TABLE));
}
ptep = pte_offset_kernel(pmd, vaddr);
do {
if (pte_none(*ptep)) {
phys_addr = memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
set_pte(ptep, pfn_pte(PFN_DOWN(phys_addr), PAGE_KERNEL));
memset(__va(phys_addr), KASAN_SHADOW_INIT, PAGE_SIZE);
}
} while (ptep++, vaddr += PAGE_SIZE, vaddr != end);
}
static void __init kasan_populate_pmd(pud_t *pud, unsigned long vaddr, unsigned long end)
{
phys_addr_t phys_addr;
pmd_t *pmdp, *p;
unsigned long next;
if (pud_none(*pud)) {
p = memblock_alloc(PTRS_PER_PMD * sizeof(pmd_t), PAGE_SIZE);
set_pud(pud, pfn_pud(PFN_DOWN(__pa(p)), PAGE_TABLE));
}
pmdp = pmd_offset(pud, vaddr);
do {
next = pmd_addr_end(vaddr, end);
if (pmd_none(*pmdp) && IS_ALIGNED(vaddr, PMD_SIZE) && (next - vaddr) >= PMD_SIZE) {
phys_addr = memblock_phys_alloc(PMD_SIZE, PMD_SIZE);
if (phys_addr) {
set_pmd(pmdp, pfn_pmd(PFN_DOWN(phys_addr), PAGE_KERNEL));
memset(__va(phys_addr), KASAN_SHADOW_INIT, PMD_SIZE);
continue;
}
}
kasan_populate_pte(pmdp, vaddr, next);
} while (pmdp++, vaddr = next, vaddr != end);
}
static void __init kasan_populate_pud(p4d_t *p4d,
unsigned long vaddr, unsigned long end)
{
phys_addr_t phys_addr;
pud_t *pudp, *p;
unsigned long next;
if (p4d_none(*p4d)) {
p = memblock_alloc(PTRS_PER_PUD * sizeof(pud_t), PAGE_SIZE);
set_p4d(p4d, pfn_p4d(PFN_DOWN(__pa(p)), PAGE_TABLE));
}
pudp = pud_offset(p4d, vaddr);
do {
next = pud_addr_end(vaddr, end);
if (pud_none(*pudp) && IS_ALIGNED(vaddr, PUD_SIZE) && (next - vaddr) >= PUD_SIZE) {
phys_addr = memblock_phys_alloc(PUD_SIZE, PUD_SIZE);
if (phys_addr) {
set_pud(pudp, pfn_pud(PFN_DOWN(phys_addr), PAGE_KERNEL));
memset(__va(phys_addr), KASAN_SHADOW_INIT, PUD_SIZE);
continue;
}
}
kasan_populate_pmd(pudp, vaddr, next);
} while (pudp++, vaddr = next, vaddr != end);
}
static void __init kasan_populate_p4d(pgd_t *pgd,
unsigned long vaddr, unsigned long end)
{
phys_addr_t phys_addr;
p4d_t *p4dp, *p;
unsigned long next;
if (pgd_none(*pgd)) {
p = memblock_alloc(PTRS_PER_P4D * sizeof(p4d_t), PAGE_SIZE);
set_pgd(pgd, pfn_pgd(PFN_DOWN(__pa(p)), PAGE_TABLE));
}
p4dp = p4d_offset(pgd, vaddr);
do {
next = p4d_addr_end(vaddr, end);
if (p4d_none(*p4dp) && IS_ALIGNED(vaddr, P4D_SIZE) && (next - vaddr) >= P4D_SIZE) {
phys_addr = memblock_phys_alloc(P4D_SIZE, P4D_SIZE);
if (phys_addr) {
set_p4d(p4dp, pfn_p4d(PFN_DOWN(phys_addr), PAGE_KERNEL));
memset(__va(phys_addr), KASAN_SHADOW_INIT, P4D_SIZE);
continue;
}
}
kasan_populate_pud(p4dp, vaddr, next);
} while (p4dp++, vaddr = next, vaddr != end);
}
static void __init kasan_populate_pgd(pgd_t *pgdp,
unsigned long vaddr, unsigned long end)
{
phys_addr_t phys_addr;
unsigned long next;
do {
next = pgd_addr_end(vaddr, end);
if (pgd_none(*pgdp) && IS_ALIGNED(vaddr, PGDIR_SIZE) &&
(next - vaddr) >= PGDIR_SIZE) {
phys_addr = memblock_phys_alloc(PGDIR_SIZE, PGDIR_SIZE);
if (phys_addr) {
set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_KERNEL));
memset(__va(phys_addr), KASAN_SHADOW_INIT, PGDIR_SIZE);
continue;
}
}
kasan_populate_p4d(pgdp, vaddr, next);
} while (pgdp++, vaddr = next, vaddr != end);
}
static void __init kasan_early_clear_pud(p4d_t *p4dp,
unsigned long vaddr, unsigned long end)
{
pud_t *pudp, *base_pud;
unsigned long next;
if (!pgtable_l4_enabled) {
pudp = (pud_t *)p4dp;
} else {
base_pud = pt_ops.get_pud_virt(pfn_to_phys(_p4d_pfn(*p4dp)));
pudp = base_pud + pud_index(vaddr);
}
do {
next = pud_addr_end(vaddr, end);
if (IS_ALIGNED(vaddr, PUD_SIZE) && (next - vaddr) >= PUD_SIZE) {
pud_clear(pudp);
continue;
}
BUG();
} while (pudp++, vaddr = next, vaddr != end);
}
static void __init kasan_early_clear_p4d(pgd_t *pgdp,
unsigned long vaddr, unsigned long end)
{
p4d_t *p4dp, *base_p4d;
unsigned long next;
if (!pgtable_l5_enabled) {
p4dp = (p4d_t *)pgdp;
} else {
base_p4d = pt_ops.get_p4d_virt(pfn_to_phys(_pgd_pfn(*pgdp)));
p4dp = base_p4d + p4d_index(vaddr);
}
do {
next = p4d_addr_end(vaddr, end);
if (pgtable_l4_enabled && IS_ALIGNED(vaddr, P4D_SIZE) &&
(next - vaddr) >= P4D_SIZE) {
p4d_clear(p4dp);
continue;
}
kasan_early_clear_pud(p4dp, vaddr, next);
} while (p4dp++, vaddr = next, vaddr != end);
}
static void __init kasan_early_clear_pgd(pgd_t *pgdp,
unsigned long vaddr, unsigned long end)
{
unsigned long next;
do {
next = pgd_addr_end(vaddr, end);
if (pgtable_l5_enabled && IS_ALIGNED(vaddr, PGDIR_SIZE) &&
(next - vaddr) >= PGDIR_SIZE) {
pgd_clear(pgdp);
continue;
}
kasan_early_clear_p4d(pgdp, vaddr, next);
} while (pgdp++, vaddr = next, vaddr != end);
}
static void __init kasan_early_populate_pud(p4d_t *p4dp,
unsigned long vaddr,
unsigned long end)
{
pud_t *pudp, *base_pud;
phys_addr_t phys_addr;
unsigned long next;
if (!pgtable_l4_enabled) {
pudp = (pud_t *)p4dp;
} else {
base_pud = pt_ops.get_pud_virt(pfn_to_phys(_p4d_pfn(*p4dp)));
pudp = base_pud + pud_index(vaddr);
}
do {
next = pud_addr_end(vaddr, end);
if (pud_none(*pudp) && IS_ALIGNED(vaddr, PUD_SIZE) &&
(next - vaddr) >= PUD_SIZE) {
phys_addr = __pa((uintptr_t)kasan_early_shadow_pmd);
set_pud(pudp, pfn_pud(PFN_DOWN(phys_addr), PAGE_TABLE));
continue;
}
BUG();
} while (pudp++, vaddr = next, vaddr != end);
}
static void __init kasan_early_populate_p4d(pgd_t *pgdp,
unsigned long vaddr,
unsigned long end)
{
p4d_t *p4dp, *base_p4d;
phys_addr_t phys_addr;
unsigned long next;
/*
* We can't use pgd_page_vaddr here as it would return a linear
* mapping address but it is not mapped yet, but when populating
* early_pg_dir, we need the physical address and when populating
* swapper_pg_dir, we need the kernel virtual address so use
* pt_ops facility.
* Note that this test is then completely equivalent to
* p4dp = p4d_offset(pgdp, vaddr)
*/
if (!pgtable_l5_enabled) {
p4dp = (p4d_t *)pgdp;
} else {
base_p4d = pt_ops.get_p4d_virt(pfn_to_phys(_pgd_pfn(*pgdp)));
p4dp = base_p4d + p4d_index(vaddr);
}
do {
next = p4d_addr_end(vaddr, end);
if (p4d_none(*p4dp) && IS_ALIGNED(vaddr, P4D_SIZE) &&
(next - vaddr) >= P4D_SIZE) {
phys_addr = __pa((uintptr_t)kasan_early_shadow_pud);
set_p4d(p4dp, pfn_p4d(PFN_DOWN(phys_addr), PAGE_TABLE));
continue;
}
kasan_early_populate_pud(p4dp, vaddr, next);
} while (p4dp++, vaddr = next, vaddr != end);
}
static void __init kasan_early_populate_pgd(pgd_t *pgdp,
unsigned long vaddr,
unsigned long end)
{
phys_addr_t phys_addr;
unsigned long next;
do {
next = pgd_addr_end(vaddr, end);
if (pgd_none(*pgdp) && IS_ALIGNED(vaddr, PGDIR_SIZE) &&
(next - vaddr) >= PGDIR_SIZE) {
phys_addr = __pa((uintptr_t)kasan_early_shadow_p4d);
set_pgd(pgdp, pfn_pgd(PFN_DOWN(phys_addr), PAGE_TABLE));
continue;
}
kasan_early_populate_p4d(pgdp, vaddr, next);
} while (pgdp++, vaddr = next, vaddr != end);
}
asmlinkage void __init kasan_early_init(void)
{
uintptr_t i;
BUILD_BUG_ON(KASAN_SHADOW_OFFSET !=
KASAN_SHADOW_END - (1UL << (64 - KASAN_SHADOW_SCALE_SHIFT)));
for (i = 0; i < PTRS_PER_PTE; ++i)
set_pte(kasan_early_shadow_pte + i,
pfn_pte(virt_to_pfn(kasan_early_shadow_page), PAGE_KERNEL));
for (i = 0; i < PTRS_PER_PMD; ++i)
set_pmd(kasan_early_shadow_pmd + i,
pfn_pmd(PFN_DOWN
(__pa((uintptr_t)kasan_early_shadow_pte)),
PAGE_TABLE));
if (pgtable_l4_enabled) {
for (i = 0; i < PTRS_PER_PUD; ++i)
set_pud(kasan_early_shadow_pud + i,
pfn_pud(PFN_DOWN
(__pa(((uintptr_t)kasan_early_shadow_pmd))),
PAGE_TABLE));
}
if (pgtable_l5_enabled) {
for (i = 0; i < PTRS_PER_P4D; ++i)
set_p4d(kasan_early_shadow_p4d + i,
pfn_p4d(PFN_DOWN
(__pa(((uintptr_t)kasan_early_shadow_pud))),
PAGE_TABLE));
}
kasan_early_populate_pgd(early_pg_dir + pgd_index(KASAN_SHADOW_START),
KASAN_SHADOW_START, KASAN_SHADOW_END);
local_flush_tlb_all();
}
void __init kasan_swapper_init(void)
{
kasan_early_populate_pgd(pgd_offset_k(KASAN_SHADOW_START),
KASAN_SHADOW_START, KASAN_SHADOW_END);
local_flush_tlb_all();
}
static void __init kasan_populate(void *start, void *end)
{
unsigned long vaddr = (unsigned long)start & PAGE_MASK;
unsigned long vend = PAGE_ALIGN((unsigned long)end);
kasan_populate_pgd(pgd_offset_k(vaddr), vaddr, vend);
}
static void __init kasan_shallow_populate_pud(p4d_t *p4d,
unsigned long vaddr, unsigned long end)
{
unsigned long next;
void *p;
pud_t *pud_k = pud_offset(p4d, vaddr);
do {
next = pud_addr_end(vaddr, end);
if (pud_none(*pud_k)) {
p = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
set_pud(pud_k, pfn_pud(PFN_DOWN(__pa(p)), PAGE_TABLE));
continue;
}
BUG();
} while (pud_k++, vaddr = next, vaddr != end);
}
static void __init kasan_shallow_populate_p4d(pgd_t *pgd,
unsigned long vaddr, unsigned long end)
{
unsigned long next;
void *p;
p4d_t *p4d_k = p4d_offset(pgd, vaddr);
do {
next = p4d_addr_end(vaddr, end);
if (p4d_none(*p4d_k)) {
p = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
set_p4d(p4d_k, pfn_p4d(PFN_DOWN(__pa(p)), PAGE_TABLE));
continue;
}
kasan_shallow_populate_pud(p4d_k, vaddr, end);
} while (p4d_k++, vaddr = next, vaddr != end);
}
static void __init kasan_shallow_populate_pgd(unsigned long vaddr, unsigned long end)
{
unsigned long next;
void *p;
pgd_t *pgd_k = pgd_offset_k(vaddr);
do {
next = pgd_addr_end(vaddr, end);
if (pgd_none(*pgd_k)) {
p = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
set_pgd(pgd_k, pfn_pgd(PFN_DOWN(__pa(p)), PAGE_TABLE));
continue;
}
kasan_shallow_populate_p4d(pgd_k, vaddr, next);
} while (pgd_k++, vaddr = next, vaddr != end);
}
static void __init kasan_shallow_populate(void *start, void *end)
{
unsigned long vaddr = (unsigned long)start & PAGE_MASK;
unsigned long vend = PAGE_ALIGN((unsigned long)end);
kasan_shallow_populate_pgd(vaddr, vend);
}
static void __init create_tmp_mapping(void)
{
void *ptr;
p4d_t *base_p4d;
/*
* We need to clean the early mapping: this is hard to achieve "in-place",
* so install a temporary mapping like arm64 and x86 do.
*/
memcpy(tmp_pg_dir, swapper_pg_dir, sizeof(pgd_t) * PTRS_PER_PGD);
/* Copy the last p4d since it is shared with the kernel mapping. */
if (pgtable_l5_enabled) {
ptr = (p4d_t *)pgd_page_vaddr(*pgd_offset_k(KASAN_SHADOW_END));
memcpy(tmp_p4d, ptr, sizeof(p4d_t) * PTRS_PER_P4D);
set_pgd(&tmp_pg_dir[pgd_index(KASAN_SHADOW_END)],
pfn_pgd(PFN_DOWN(__pa(tmp_p4d)), PAGE_TABLE));
base_p4d = tmp_p4d;
} else {
base_p4d = (p4d_t *)tmp_pg_dir;
}
/* Copy the last pud since it is shared with the kernel mapping. */
if (pgtable_l4_enabled) {
ptr = (pud_t *)p4d_page_vaddr(*(base_p4d + p4d_index(KASAN_SHADOW_END)));
memcpy(tmp_pud, ptr, sizeof(pud_t) * PTRS_PER_PUD);
set_p4d(&base_p4d[p4d_index(KASAN_SHADOW_END)],
pfn_p4d(PFN_DOWN(__pa(tmp_pud)), PAGE_TABLE));
}
}
void __init kasan_init(void)
{
phys_addr_t p_start, p_end;
u64 i;
create_tmp_mapping();
csr_write(CSR_SATP, PFN_DOWN(__pa(tmp_pg_dir)) | satp_mode);
kasan_early_clear_pgd(pgd_offset_k(KASAN_SHADOW_START),
KASAN_SHADOW_START, KASAN_SHADOW_END);
kasan_populate_early_shadow((void *)kasan_mem_to_shadow((void *)FIXADDR_START),
(void *)kasan_mem_to_shadow((void *)VMALLOC_START));
if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
kasan_shallow_populate(
(void *)kasan_mem_to_shadow((void *)VMALLOC_START),
(void *)kasan_mem_to_shadow((void *)VMALLOC_END));
/* Shallow populate modules and BPF which are vmalloc-allocated */
kasan_shallow_populate(
(void *)kasan_mem_to_shadow((void *)MODULES_VADDR),
(void *)kasan_mem_to_shadow((void *)MODULES_END));
} else {
kasan_populate_early_shadow((void *)kasan_mem_to_shadow((void *)VMALLOC_START),
(void *)kasan_mem_to_shadow((void *)VMALLOC_END));
}
/* Populate the linear mapping */
for_each_mem_range(i, &p_start, &p_end) {
void *start = (void *)__va(p_start);
void *end = (void *)__va(p_end);
if (start >= end)
break;
kasan_populate(kasan_mem_to_shadow(start), kasan_mem_to_shadow(end));
}
/* Populate kernel */
kasan_populate(kasan_mem_to_shadow((const void *)MODULES_END),
kasan_mem_to_shadow((const void *)MODULES_VADDR + SZ_2G));
for (i = 0; i < PTRS_PER_PTE; i++)
set_pte(&kasan_early_shadow_pte[i],
mk_pte(virt_to_page(kasan_early_shadow_page),
__pgprot(_PAGE_PRESENT | _PAGE_READ |
_PAGE_ACCESSED)));
memset(kasan_early_shadow_page, KASAN_SHADOW_INIT, PAGE_SIZE);
init_task.kasan_depth = 0;
csr_write(CSR_SATP, PFN_DOWN(__pa(swapper_pg_dir)) | satp_mode);
local_flush_tlb_all();
}