diff options
Diffstat (limited to 'arch/s390/mm/kasan_init.c')
| -rw-r--r-- | arch/s390/mm/kasan_init.c | 382 |
1 files changed, 0 insertions, 382 deletions
diff --git a/arch/s390/mm/kasan_init.c b/arch/s390/mm/kasan_init.c deleted file mode 100644 index 460f25572940..000000000000 --- a/arch/s390/mm/kasan_init.c +++ /dev/null @@ -1,382 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -#include <linux/kasan.h> -#include <linux/sched/task.h> -#include <linux/memblock.h> -#include <asm/pgalloc.h> -#include <asm/pgtable.h> -#include <asm/kasan.h> -#include <asm/mem_detect.h> -#include <asm/processor.h> -#include <asm/sclp.h> -#include <asm/facility.h> -#include <asm/sections.h> -#include <asm/setup.h> - -static unsigned long segment_pos __initdata; -static unsigned long segment_low __initdata; -static unsigned long pgalloc_pos __initdata; -static unsigned long pgalloc_low __initdata; -static unsigned long pgalloc_freeable __initdata; -static bool has_edat __initdata; -static bool has_nx __initdata; - -#define __sha(x) ((unsigned long)kasan_mem_to_shadow((void *)x)) - -static pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); - -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) -{ - segment_pos -= _SEGMENT_SIZE; - - if (segment_pos < segment_low) - kasan_early_panic("out of memory during initialisation\n"); - - return (void *)segment_pos; -} - -static void * __init kasan_early_alloc_pages(unsigned int order) -{ - pgalloc_pos -= (PAGE_SIZE << order); - - if (pgalloc_pos < pgalloc_low) - kasan_early_panic("out of memory during initialisation\n"); - - return (void *)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_ONE2ONE, - POPULATE_MAP, - POPULATE_ZERO_SHADOW -}; -static void __init kasan_early_vmemmap_populate(unsigned long address, - unsigned long end, - enum populate_mode mode) -{ - unsigned long pgt_prot_zero, pgt_prot, sgt_prot; - pgd_t *pg_dir; - p4d_t *p4_dir; - pud_t *pu_dir; - pmd_t *pm_dir; - pte_t *pt_dir; - - pgt_prot_zero = pgprot_val(PAGE_KERNEL_RO); - if (!has_nx) - pgt_prot_zero &= ~_PAGE_NOEXEC; - pgt_prot = pgprot_val(PAGE_KERNEL_EXEC); - sgt_prot = pgprot_val(SEGMENT_KERNEL_EXEC); - - 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); - } - - 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 (mode == POPULATE_ZERO_SHADOW && - IS_ALIGNED(address, PMD_SIZE) && - end - address >= PMD_SIZE) { - pmd_populate(&init_mm, pm_dir, - kasan_early_shadow_pte); - address = (address + PMD_SIZE) & PMD_MASK; - continue; - } - /* the first megabyte of 1:1 is mapped with 4k pages */ - if (has_edat && address && end - address >= PMD_SIZE && - mode != POPULATE_ZERO_SHADOW) { - void *page; - - if (mode == POPULATE_ONE2ONE) { - page = (void *)address; - } else { - page = kasan_early_alloc_segment(); - memset(page, 0, _SEGMENT_SIZE); - } - pmd_val(*pm_dir) = __pa(page) | sgt_prot; - 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_ONE2ONE: - page = (void *)address; - pte_val(*pt_dir) = __pa(page) | pgt_prot; - break; - case POPULATE_MAP: - page = kasan_early_alloc_pages(0); - memset(page, 0, PAGE_SIZE); - pte_val(*pt_dir) = __pa(page) | pgt_prot; - break; - case POPULATE_ZERO_SHADOW: - page = kasan_early_shadow_page; - pte_val(*pt_dir) = __pa(page) | pgt_prot_zero; - break; - } - } - address += PAGE_SIZE; - } -} - -static void __init kasan_set_pgd(pgd_t *pgd, unsigned long asce_type) -{ - unsigned long asce_bits; - - asce_bits = asce_type | _ASCE_TABLE_LENGTH; - S390_lowcore.kernel_asce = (__pa(pgd) & PAGE_MASK) | asce_bits; - S390_lowcore.user_asce = S390_lowcore.kernel_asce; - - __ctl_load(S390_lowcore.kernel_asce, 1, 1); - __ctl_load(S390_lowcore.kernel_asce, 7, 7); - __ctl_load(S390_lowcore.kernel_asce, 13, 13); -} - -static void __init kasan_enable_dat(void) -{ - psw_t psw; - - psw.mask = __extract_psw(); - psw_bits(psw).dat = 1; - psw_bits(psw).as = PSW_BITS_AS_HOME; - __load_psw_mask(psw.mask); -} - -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) -{ - unsigned long untracked_mem_end; - unsigned long shadow_alloc_size; - unsigned long initrd_end; - unsigned long asce_type; - unsigned long memsize; - unsigned long vmax; - unsigned long pgt_prot = pgprot_val(PAGE_KERNEL_RO); - pte_t pte_z; - 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); - - kasan_early_detect_facilities(); - if (!has_nx) - pgt_prot &= ~_PAGE_NOEXEC; - pte_z = __pte(__pa(kasan_early_shadow_page) | pgt_prot); - - memsize = get_mem_detect_end(); - if (!memsize) - kasan_early_panic("cannot detect physical memory size\n"); - /* respect mem= cmdline parameter */ - if (memory_end_set && memsize > memory_end) - memsize = memory_end; - if (IS_ENABLED(CONFIG_CRASH_DUMP) && OLDMEM_BASE) - memsize = min(memsize, OLDMEM_SIZE); - memsize = min(memsize, KASAN_SHADOW_START); - - if (IS_ENABLED(CONFIG_KASAN_S390_4_LEVEL_PAGING)) { - /* 4 level paging */ - BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, P4D_SIZE)); - BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, P4D_SIZE)); - crst_table_init((unsigned long *)early_pg_dir, - _REGION2_ENTRY_EMPTY); - untracked_mem_end = vmax = _REGION1_SIZE; - asce_type = _ASCE_TYPE_REGION2; - } else { - /* 3 level paging */ - BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_START, PUD_SIZE)); - BUILD_BUG_ON(!IS_ALIGNED(KASAN_SHADOW_END, PUD_SIZE)); - crst_table_init((unsigned long *)early_pg_dir, - _REGION3_ENTRY_EMPTY); - untracked_mem_end = vmax = _REGION2_SIZE; - asce_type = _ASCE_TYPE_REGION3; - } - - /* 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); - - shadow_alloc_size = memsize >> KASAN_SHADOW_SCALE_SHIFT; - pgalloc_low = round_up((unsigned long)_end, _SEGMENT_SIZE); - if (IS_ENABLED(CONFIG_BLK_DEV_INITRD)) { - initrd_end = - round_up(INITRD_START + INITRD_SIZE, _SEGMENT_SIZE); - pgalloc_low = max(pgalloc_low, initrd_end); - } - - if (pgalloc_low + shadow_alloc_size > memsize) - kasan_early_panic("out of memory during initialisation\n"); - - if (has_edat) { - segment_pos = round_down(memsize, _SEGMENT_SIZE); - segment_low = segment_pos - shadow_alloc_size; - pgalloc_pos = segment_low; - } else { - pgalloc_pos = memsize; - } - init_mm.pgd = early_pg_dir; - /* - * Current memory layout: - * +- 0 -------------+ +- shadow start -+ - * | 1:1 ram mapping | /| 1/8 ram | - * +- end of ram ----+ / +----------------+ - * | ... gap ... |/ | kasan | - * +- shadow start --+ | zero | - * | 1/8 addr space | | page | - * +- shadow end -+ | mapping | - * | ... gap ... |\ | (untracked) | - * +- modules vaddr -+ \ +----------------+ - * | 2Gb | \| unmapped | allocated per module - * +-----------------+ +- shadow end ---+ - */ - /* populate kasan shadow (for identity mapping and zero page mapping) */ - kasan_early_vmemmap_populate(__sha(0), __sha(memsize), POPULATE_MAP); - if (IS_ENABLED(CONFIG_MODULES)) - untracked_mem_end = vmax - MODULES_LEN; - kasan_early_vmemmap_populate(__sha(max_physmem_end), - __sha(untracked_mem_end), - POPULATE_ZERO_SHADOW); - /* memory allocated for identity mapping structs will be freed later */ - pgalloc_freeable = pgalloc_pos; - /* populate identity mapping */ - kasan_early_vmemmap_populate(0, memsize, POPULATE_ONE2ONE); - kasan_set_pgd(early_pg_dir, asce_type); - kasan_enable_dat(); - /* enable kasan */ - init_task.kasan_depth = 0; - memblock_reserve(pgalloc_pos, memsize - pgalloc_pos); - sclp_early_printk("KernelAddressSanitizer initialized\n"); -} - -void __init kasan_copy_shadow(pgd_t *pg_dir) -{ - /* - * At this point we are still running on early pages setup early_pg_dir, - * while swapper_pg_dir has just been initialized with identity mapping. - * Carry over shadow memory region from early_pg_dir to swapper_pg_dir. - */ - - pgd_t *pg_dir_src; - pgd_t *pg_dir_dst; - p4d_t *p4_dir_src; - p4d_t *p4_dir_dst; - pud_t *pu_dir_src; - pud_t *pu_dir_dst; - - pg_dir_src = pgd_offset_raw(early_pg_dir, KASAN_SHADOW_START); - pg_dir_dst = pgd_offset_raw(pg_dir, KASAN_SHADOW_START); - p4_dir_src = p4d_offset(pg_dir_src, KASAN_SHADOW_START); - p4_dir_dst = p4d_offset(pg_dir_dst, KASAN_SHADOW_START); - if (!p4d_folded(*p4_dir_src)) { - /* 4 level paging */ - memcpy(p4_dir_dst, p4_dir_src, - (KASAN_SHADOW_SIZE >> P4D_SHIFT) * sizeof(p4d_t)); - return; - } - /* 3 level paging */ - pu_dir_src = pud_offset(p4_dir_src, KASAN_SHADOW_START); - pu_dir_dst = pud_offset(p4_dir_dst, KASAN_SHADOW_START); - memcpy(pu_dir_dst, pu_dir_src, - (KASAN_SHADOW_SIZE >> PUD_SHIFT) * sizeof(pud_t)); -} - -void __init kasan_free_early_identity(void) -{ - memblock_free(pgalloc_pos, pgalloc_freeable - pgalloc_pos); -} |