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-rw-r--r--arch/s390/mm/kasan_init.c298
1 files changed, 0 insertions, 298 deletions
diff --git a/arch/s390/mm/kasan_init.c b/arch/s390/mm/kasan_init.c
deleted file mode 100644
index 2b20382f1bd8..000000000000
--- a/arch/s390/mm/kasan_init.c
+++ /dev/null
@@ -1,298 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-#include <linux/memblock.h>
-#include <linux/pgtable.h>
-#include <linux/kasan.h>
-#include <asm/physmem_info.h>
-#include <asm/processor.h>
-#include <asm/facility.h>
-#include <asm/pgalloc.h>
-#include <asm/sclp.h>
-
-static unsigned long pgalloc_pos __initdata;
-static unsigned long segment_pos __initdata;
-static bool has_edat __initdata;
-static bool has_nx __initdata;
-
-#define __sha(x) ((unsigned long)kasan_mem_to_shadow((void *)x))
-
-static void __init kasan_early_panic(const char *reason)
-{
- sclp_early_printk("The Linux kernel failed to boot with the KernelAddressSanitizer:\n");
- sclp_early_printk(reason);
- disabled_wait();
-}
-
-static void * __init kasan_early_alloc_segment(void)
-{
- unsigned long addr = segment_pos;
-
- segment_pos += _SEGMENT_SIZE;
- if (segment_pos > pgalloc_pos)
- kasan_early_panic("out of memory during initialisation\n");
-
- return __va(addr);
-}
-
-static void * __init kasan_early_alloc_pages(unsigned int order)
-{
- pgalloc_pos -= (PAGE_SIZE << order);
-
- if (segment_pos > pgalloc_pos)
- kasan_early_panic("out of memory during initialisation\n");
-
- return __va(pgalloc_pos);
-}
-
-static void * __init kasan_early_crst_alloc(unsigned long val)
-{
- unsigned long *table;
-
- table = kasan_early_alloc_pages(CRST_ALLOC_ORDER);
- if (table)
- crst_table_init(table, val);
- return table;
-}
-
-static pte_t * __init kasan_early_pte_alloc(void)
-{
- static void *pte_leftover;
- pte_t *pte;
-
- BUILD_BUG_ON(_PAGE_TABLE_SIZE * 2 != PAGE_SIZE);
-
- if (!pte_leftover) {
- pte_leftover = kasan_early_alloc_pages(0);
- pte = pte_leftover + _PAGE_TABLE_SIZE;
- } else {
- pte = pte_leftover;
- pte_leftover = NULL;
- }
- memset64((u64 *)pte, _PAGE_INVALID, PTRS_PER_PTE);
- return pte;
-}
-
-enum populate_mode {
- POPULATE_MAP,
- POPULATE_ZERO_SHADOW,
- POPULATE_SHALLOW
-};
-
-static inline pgprot_t pgprot_clear_bit(pgprot_t pgprot, unsigned long bit)
-{
- return __pgprot(pgprot_val(pgprot) & ~bit);
-}
-
-static void __init kasan_early_pgtable_populate(unsigned long address,
- unsigned long end,
- enum populate_mode mode)
-{
- pgprot_t pgt_prot_zero = PAGE_KERNEL_RO;
- pgprot_t pgt_prot = PAGE_KERNEL;
- pgprot_t sgt_prot = SEGMENT_KERNEL;
- pgd_t *pg_dir;
- p4d_t *p4_dir;
- pud_t *pu_dir;
- pmd_t *pm_dir;
- pte_t *pt_dir;
- pmd_t pmd;
- pte_t pte;
-
- if (!has_nx) {
- pgt_prot_zero = pgprot_clear_bit(pgt_prot_zero, _PAGE_NOEXEC);
- pgt_prot = pgprot_clear_bit(pgt_prot, _PAGE_NOEXEC);
- sgt_prot = pgprot_clear_bit(sgt_prot, _SEGMENT_ENTRY_NOEXEC);
- }
-
- while (address < end) {
- pg_dir = pgd_offset_k(address);
- if (pgd_none(*pg_dir)) {
- if (mode == POPULATE_ZERO_SHADOW &&
- IS_ALIGNED(address, PGDIR_SIZE) &&
- end - address >= PGDIR_SIZE) {
- pgd_populate(&init_mm, pg_dir,
- kasan_early_shadow_p4d);
- address = (address + PGDIR_SIZE) & PGDIR_MASK;
- continue;
- }
- p4_dir = kasan_early_crst_alloc(_REGION2_ENTRY_EMPTY);
- pgd_populate(&init_mm, pg_dir, p4_dir);
- }
-
- if (mode == POPULATE_SHALLOW) {
- address = (address + P4D_SIZE) & P4D_MASK;
- continue;
- }
-
- p4_dir = p4d_offset(pg_dir, address);
- if (p4d_none(*p4_dir)) {
- if (mode == POPULATE_ZERO_SHADOW &&
- IS_ALIGNED(address, P4D_SIZE) &&
- end - address >= P4D_SIZE) {
- p4d_populate(&init_mm, p4_dir,
- kasan_early_shadow_pud);
- address = (address + P4D_SIZE) & P4D_MASK;
- continue;
- }
- pu_dir = kasan_early_crst_alloc(_REGION3_ENTRY_EMPTY);
- p4d_populate(&init_mm, p4_dir, pu_dir);
- }
-
- pu_dir = pud_offset(p4_dir, address);
- if (pud_none(*pu_dir)) {
- if (mode == POPULATE_ZERO_SHADOW &&
- IS_ALIGNED(address, PUD_SIZE) &&
- end - address >= PUD_SIZE) {
- pud_populate(&init_mm, pu_dir,
- kasan_early_shadow_pmd);
- address = (address + PUD_SIZE) & PUD_MASK;
- continue;
- }
- pm_dir = kasan_early_crst_alloc(_SEGMENT_ENTRY_EMPTY);
- pud_populate(&init_mm, pu_dir, pm_dir);
- }
-
- pm_dir = pmd_offset(pu_dir, address);
- if (pmd_none(*pm_dir)) {
- if (IS_ALIGNED(address, PMD_SIZE) &&
- end - address >= PMD_SIZE) {
- if (mode == POPULATE_ZERO_SHADOW) {
- pmd_populate(&init_mm, pm_dir, kasan_early_shadow_pte);
- address = (address + PMD_SIZE) & PMD_MASK;
- continue;
- } else if (has_edat) {
- void *page = kasan_early_alloc_segment();
-
- memset(page, 0, _SEGMENT_SIZE);
- pmd = __pmd(__pa(page));
- pmd = set_pmd_bit(pmd, sgt_prot);
- set_pmd(pm_dir, pmd);
- address = (address + PMD_SIZE) & PMD_MASK;
- continue;
- }
- }
- pt_dir = kasan_early_pte_alloc();
- pmd_populate(&init_mm, pm_dir, pt_dir);
- } else if (pmd_large(*pm_dir)) {
- address = (address + PMD_SIZE) & PMD_MASK;
- continue;
- }
-
- pt_dir = pte_offset_kernel(pm_dir, address);
- if (pte_none(*pt_dir)) {
- void *page;
-
- switch (mode) {
- case POPULATE_MAP:
- page = kasan_early_alloc_pages(0);
- memset(page, 0, PAGE_SIZE);
- pte = __pte(__pa(page));
- pte = set_pte_bit(pte, pgt_prot);
- set_pte(pt_dir, pte);
- break;
- case POPULATE_ZERO_SHADOW:
- page = kasan_early_shadow_page;
- pte = __pte(__pa(page));
- pte = set_pte_bit(pte, pgt_prot_zero);
- set_pte(pt_dir, pte);
- break;
- case POPULATE_SHALLOW:
- /* should never happen */
- break;
- }
- }
- address += PAGE_SIZE;
- }
-}
-
-static void __init kasan_early_detect_facilities(void)
-{
- if (test_facility(8)) {
- has_edat = true;
- __ctl_set_bit(0, 23);
- }
- if (!noexec_disabled && test_facility(130)) {
- has_nx = true;
- __ctl_set_bit(0, 20);
- }
-}
-
-void __init kasan_early_init(void)
-{
- pte_t pte_z = __pte(__pa(kasan_early_shadow_page) | pgprot_val(PAGE_KERNEL_RO));
- pmd_t pmd_z = __pmd(__pa(kasan_early_shadow_pte) | _SEGMENT_ENTRY);
- pud_t pud_z = __pud(__pa(kasan_early_shadow_pmd) | _REGION3_ENTRY);
- p4d_t p4d_z = __p4d(__pa(kasan_early_shadow_pud) | _REGION2_ENTRY);
- unsigned long pgalloc_pos_initial, segment_pos_initial;
- unsigned long untracked_end = MODULES_VADDR;
- unsigned long start, end;
- int i;
-
- kasan_early_detect_facilities();
- if (!has_nx)
- pte_z = clear_pte_bit(pte_z, __pgprot(_PAGE_NOEXEC));
-
- BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, P4D_SIZE));
- BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, P4D_SIZE));
-
- /* init kasan zero shadow */
- crst_table_init((unsigned long *)kasan_early_shadow_p4d, p4d_val(p4d_z));
- crst_table_init((unsigned long *)kasan_early_shadow_pud, pud_val(pud_z));
- crst_table_init((unsigned long *)kasan_early_shadow_pmd, pmd_val(pmd_z));
- memset64((u64 *)kasan_early_shadow_pte, pte_val(pte_z), PTRS_PER_PTE);
-
- /* segment allocations go bottom up -> <- pgalloc go top down */
- segment_pos_initial = physmem_info.reserved[RR_KASAN].start;
- segment_pos = segment_pos_initial;
- pgalloc_pos_initial = physmem_info.reserved[RR_KASAN].end;
- pgalloc_pos = pgalloc_pos_initial;
- /*
- * Current memory layout:
- * +- 0 -------------+ +- shadow start -+
- * |1:1 ident mapping| /|1/8 of ident map|
- * | | / | |
- * +-end of ident map+ / +----------------+
- * | ... gap ... | / | kasan |
- * | | / | zero page |
- * +- vmalloc area -+ / | mapping |
- * | vmalloc_size | / | (untracked) |
- * +- modules vaddr -+ / +----------------+
- * | 2Gb |/ | unmapped | allocated per module
- * +- shadow start -+ +----------------+
- * | 1/8 addr space | | zero pg mapping| (untracked)
- * +- shadow end ----+---------+- shadow end ---+
- *
- * Current memory layout (KASAN_VMALLOC):
- * +- 0 -------------+ +- shadow start -+
- * |1:1 ident mapping| /|1/8 of ident map|
- * | | / | |
- * +-end of ident map+ / +----------------+
- * | ... gap ... | / | kasan zero page| (untracked)
- * | | / | mapping |
- * +- vmalloc area -+ / +----------------+
- * | vmalloc_size | / |shallow populate|
- * +- modules vaddr -+ / +----------------+
- * | 2Gb |/ |shallow populate|
- * +- shadow start -+ +----------------+
- * | 1/8 addr space | | zero pg mapping| (untracked)
- * +- shadow end ----+---------+- shadow end ---+
- */
- /* populate kasan shadow (for identity mapping and zero page mapping) */
- for_each_physmem_usable_range(i, &start, &end)
- kasan_early_pgtable_populate(__sha(start), __sha(end), POPULATE_MAP);
- if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
- untracked_end = VMALLOC_START;
- /* shallowly populate kasan shadow for vmalloc and modules */
- kasan_early_pgtable_populate(__sha(VMALLOC_START), __sha(MODULES_END),
- POPULATE_SHALLOW);
- }
- /* populate kasan shadow for untracked memory */
- kasan_early_pgtable_populate(__sha(ident_map_size), __sha(untracked_end),
- POPULATE_ZERO_SHADOW);
- kasan_early_pgtable_populate(__sha(MODULES_END), __sha(_REGION1_SIZE),
- POPULATE_ZERO_SHADOW);
- /* enable kasan */
- init_task.kasan_depth = 0;
- sclp_early_printk("KernelAddressSanitizer initialized\n");
- memblock_reserve(segment_pos_initial, segment_pos - segment_pos_initial);
- memblock_reserve(pgalloc_pos, pgalloc_pos_initial - pgalloc_pos);
-}
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