| // 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(); |
| } |