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Diffstat (limited to 'arch/arm64/mm/dump.c')
| -rw-r--r-- | arch/arm64/mm/dump.c | 423 |
1 files changed, 0 insertions, 423 deletions
diff --git a/arch/arm64/mm/dump.c b/arch/arm64/mm/dump.c deleted file mode 100644 index 0a920b538a89..000000000000 --- a/arch/arm64/mm/dump.c +++ /dev/null @@ -1,423 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * Copyright (c) 2014, The Linux Foundation. All rights reserved. - * Debug helper to dump the current kernel pagetables of the system - * so that we can see what the various memory ranges are set to. - * - * Derived from x86 and arm implementation: - * (C) Copyright 2008 Intel Corporation - * - * Author: Arjan van de Ven <arjan@linux.intel.com> - */ -#include <linux/debugfs.h> -#include <linux/errno.h> -#include <linux/fs.h> -#include <linux/io.h> -#include <linux/init.h> -#include <linux/mm.h> -#include <linux/sched.h> -#include <linux/seq_file.h> - -#include <asm/fixmap.h> -#include <asm/kasan.h> -#include <asm/memory.h> -#include <asm/pgtable.h> -#include <asm/pgtable-hwdef.h> -#include <asm/ptdump.h> - - -enum address_markers_idx { - PAGE_OFFSET_NR = 0, - PAGE_END_NR, -#ifdef CONFIG_KASAN - KASAN_START_NR, -#endif -}; - -static struct addr_marker address_markers[] = { - { PAGE_OFFSET, "Linear Mapping start" }, - { 0 /* PAGE_END */, "Linear Mapping end" }, -#ifdef CONFIG_KASAN - { 0 /* KASAN_SHADOW_START */, "Kasan shadow start" }, - { KASAN_SHADOW_END, "Kasan shadow end" }, -#endif - { MODULES_VADDR, "Modules start" }, - { MODULES_END, "Modules end" }, - { VMALLOC_START, "vmalloc() area" }, - { VMALLOC_END, "vmalloc() end" }, - { FIXADDR_START, "Fixmap start" }, - { FIXADDR_TOP, "Fixmap end" }, - { PCI_IO_START, "PCI I/O start" }, - { PCI_IO_END, "PCI I/O end" }, -#ifdef CONFIG_SPARSEMEM_VMEMMAP - { VMEMMAP_START, "vmemmap start" }, - { VMEMMAP_START + VMEMMAP_SIZE, "vmemmap end" }, -#endif - { -1, NULL }, -}; - -#define pt_dump_seq_printf(m, fmt, args...) \ -({ \ - if (m) \ - seq_printf(m, fmt, ##args); \ -}) - -#define pt_dump_seq_puts(m, fmt) \ -({ \ - if (m) \ - seq_printf(m, fmt); \ -}) - -/* - * The page dumper groups page table entries of the same type into a single - * description. It uses pg_state to track the range information while - * iterating over the pte entries. When the continuity is broken it then - * dumps out a description of the range. - */ -struct pg_state { - struct seq_file *seq; - const struct addr_marker *marker; - unsigned long start_address; - unsigned level; - u64 current_prot; - bool check_wx; - unsigned long wx_pages; - unsigned long uxn_pages; -}; - -struct prot_bits { - u64 mask; - u64 val; - const char *set; - const char *clear; -}; - -static const struct prot_bits pte_bits[] = { - { - .mask = PTE_VALID, - .val = PTE_VALID, - .set = " ", - .clear = "F", - }, { - .mask = PTE_USER, - .val = PTE_USER, - .set = "USR", - .clear = " ", - }, { - .mask = PTE_RDONLY, - .val = PTE_RDONLY, - .set = "ro", - .clear = "RW", - }, { - .mask = PTE_PXN, - .val = PTE_PXN, - .set = "NX", - .clear = "x ", - }, { - .mask = PTE_SHARED, - .val = PTE_SHARED, - .set = "SHD", - .clear = " ", - }, { - .mask = PTE_AF, - .val = PTE_AF, - .set = "AF", - .clear = " ", - }, { - .mask = PTE_NG, - .val = PTE_NG, - .set = "NG", - .clear = " ", - }, { - .mask = PTE_CONT, - .val = PTE_CONT, - .set = "CON", - .clear = " ", - }, { - .mask = PTE_TABLE_BIT, - .val = PTE_TABLE_BIT, - .set = " ", - .clear = "BLK", - }, { - .mask = PTE_UXN, - .val = PTE_UXN, - .set = "UXN", - .clear = " ", - }, { - .mask = PTE_ATTRINDX_MASK, - .val = PTE_ATTRINDX(MT_DEVICE_nGnRnE), - .set = "DEVICE/nGnRnE", - }, { - .mask = PTE_ATTRINDX_MASK, - .val = PTE_ATTRINDX(MT_DEVICE_nGnRE), - .set = "DEVICE/nGnRE", - }, { - .mask = PTE_ATTRINDX_MASK, - .val = PTE_ATTRINDX(MT_DEVICE_GRE), - .set = "DEVICE/GRE", - }, { - .mask = PTE_ATTRINDX_MASK, - .val = PTE_ATTRINDX(MT_NORMAL_NC), - .set = "MEM/NORMAL-NC", - }, { - .mask = PTE_ATTRINDX_MASK, - .val = PTE_ATTRINDX(MT_NORMAL), - .set = "MEM/NORMAL", - } -}; - -struct pg_level { - const struct prot_bits *bits; - const char *name; - size_t num; - u64 mask; -}; - -static struct pg_level pg_level[] = { - { - }, { /* pgd */ - .name = "PGD", - .bits = pte_bits, - .num = ARRAY_SIZE(pte_bits), - }, { /* pud */ - .name = (CONFIG_PGTABLE_LEVELS > 3) ? "PUD" : "PGD", - .bits = pte_bits, - .num = ARRAY_SIZE(pte_bits), - }, { /* pmd */ - .name = (CONFIG_PGTABLE_LEVELS > 2) ? "PMD" : "PGD", - .bits = pte_bits, - .num = ARRAY_SIZE(pte_bits), - }, { /* pte */ - .name = "PTE", - .bits = pte_bits, - .num = ARRAY_SIZE(pte_bits), - }, -}; - -static void dump_prot(struct pg_state *st, const struct prot_bits *bits, - size_t num) -{ - unsigned i; - - for (i = 0; i < num; i++, bits++) { - const char *s; - - if ((st->current_prot & bits->mask) == bits->val) - s = bits->set; - else - s = bits->clear; - - if (s) - pt_dump_seq_printf(st->seq, " %s", s); - } -} - -static void note_prot_uxn(struct pg_state *st, unsigned long addr) -{ - if (!st->check_wx) - return; - - if ((st->current_prot & PTE_UXN) == PTE_UXN) - return; - - WARN_ONCE(1, "arm64/mm: Found non-UXN mapping at address %p/%pS\n", - (void *)st->start_address, (void *)st->start_address); - - st->uxn_pages += (addr - st->start_address) / PAGE_SIZE; -} - -static void note_prot_wx(struct pg_state *st, unsigned long addr) -{ - if (!st->check_wx) - return; - if ((st->current_prot & PTE_RDONLY) == PTE_RDONLY) - return; - if ((st->current_prot & PTE_PXN) == PTE_PXN) - return; - - WARN_ONCE(1, "arm64/mm: Found insecure W+X mapping at address %p/%pS\n", - (void *)st->start_address, (void *)st->start_address); - - st->wx_pages += (addr - st->start_address) / PAGE_SIZE; -} - -static void note_page(struct pg_state *st, unsigned long addr, unsigned level, - u64 val) -{ - static const char units[] = "KMGTPE"; - u64 prot = val & pg_level[level].mask; - - if (!st->level) { - st->level = level; - st->current_prot = prot; - st->start_address = addr; - pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); - } else if (prot != st->current_prot || level != st->level || - addr >= st->marker[1].start_address) { - const char *unit = units; - unsigned long delta; - - if (st->current_prot) { - note_prot_uxn(st, addr); - note_prot_wx(st, addr); - pt_dump_seq_printf(st->seq, "0x%016lx-0x%016lx ", - st->start_address, addr); - - delta = (addr - st->start_address) >> 10; - while (!(delta & 1023) && unit[1]) { - delta >>= 10; - unit++; - } - pt_dump_seq_printf(st->seq, "%9lu%c %s", delta, *unit, - pg_level[st->level].name); - if (pg_level[st->level].bits) - dump_prot(st, pg_level[st->level].bits, - pg_level[st->level].num); - pt_dump_seq_puts(st->seq, "\n"); - } - - if (addr >= st->marker[1].start_address) { - st->marker++; - pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); - } - - st->start_address = addr; - st->current_prot = prot; - st->level = level; - } - - if (addr >= st->marker[1].start_address) { - st->marker++; - pt_dump_seq_printf(st->seq, "---[ %s ]---\n", st->marker->name); - } - -} - -static void walk_pte(struct pg_state *st, pmd_t *pmdp, unsigned long start, - unsigned long end) -{ - unsigned long addr = start; - pte_t *ptep = pte_offset_kernel(pmdp, start); - - do { - note_page(st, addr, 4, READ_ONCE(pte_val(*ptep))); - } while (ptep++, addr += PAGE_SIZE, addr != end); -} - -static void walk_pmd(struct pg_state *st, pud_t *pudp, unsigned long start, - unsigned long end) -{ - unsigned long next, addr = start; - pmd_t *pmdp = pmd_offset(pudp, start); - - do { - pmd_t pmd = READ_ONCE(*pmdp); - next = pmd_addr_end(addr, end); - - if (pmd_none(pmd) || pmd_sect(pmd)) { - note_page(st, addr, 3, pmd_val(pmd)); - } else { - BUG_ON(pmd_bad(pmd)); - walk_pte(st, pmdp, addr, next); - } - } while (pmdp++, addr = next, addr != end); -} - -static void walk_pud(struct pg_state *st, pgd_t *pgdp, unsigned long start, - unsigned long end) -{ - unsigned long next, addr = start; - pud_t *pudp = pud_offset(pgdp, start); - - do { - pud_t pud = READ_ONCE(*pudp); - next = pud_addr_end(addr, end); - - if (pud_none(pud) || pud_sect(pud)) { - note_page(st, addr, 2, pud_val(pud)); - } else { - BUG_ON(pud_bad(pud)); - walk_pmd(st, pudp, addr, next); - } - } while (pudp++, addr = next, addr != end); -} - -static void walk_pgd(struct pg_state *st, struct mm_struct *mm, - unsigned long start) -{ - unsigned long end = (start < TASK_SIZE_64) ? TASK_SIZE_64 : 0; - unsigned long next, addr = start; - pgd_t *pgdp = pgd_offset(mm, start); - - do { - pgd_t pgd = READ_ONCE(*pgdp); - next = pgd_addr_end(addr, end); - - if (pgd_none(pgd)) { - note_page(st, addr, 1, pgd_val(pgd)); - } else { - BUG_ON(pgd_bad(pgd)); - walk_pud(st, pgdp, addr, next); - } - } while (pgdp++, addr = next, addr != end); -} - -void ptdump_walk_pgd(struct seq_file *m, struct ptdump_info *info) -{ - struct pg_state st = { - .seq = m, - .marker = info->markers, - }; - - walk_pgd(&st, info->mm, info->base_addr); - - note_page(&st, 0, 0, 0); -} - -static void ptdump_initialize(void) -{ - unsigned i, j; - - for (i = 0; i < ARRAY_SIZE(pg_level); i++) - if (pg_level[i].bits) - for (j = 0; j < pg_level[i].num; j++) - pg_level[i].mask |= pg_level[i].bits[j].mask; -} - -static struct ptdump_info kernel_ptdump_info = { - .mm = &init_mm, - .markers = address_markers, - .base_addr = PAGE_OFFSET, -}; - -void ptdump_check_wx(void) -{ - struct pg_state st = { - .seq = NULL, - .marker = (struct addr_marker[]) { - { 0, NULL}, - { -1, NULL}, - }, - .check_wx = true, - }; - - walk_pgd(&st, &init_mm, PAGE_OFFSET); - note_page(&st, 0, 0, 0); - if (st.wx_pages || st.uxn_pages) - pr_warn("Checked W+X mappings: FAILED, %lu W+X pages found, %lu non-UXN pages found\n", - st.wx_pages, st.uxn_pages); - else - pr_info("Checked W+X mappings: passed, no W+X pages found\n"); -} - -static int ptdump_init(void) -{ - address_markers[PAGE_END_NR].start_address = PAGE_END; -#ifdef CONFIG_KASAN - address_markers[KASAN_START_NR].start_address = KASAN_SHADOW_START; -#endif - ptdump_initialize(); - ptdump_debugfs_register(&kernel_ptdump_info, "kernel_page_tables"); - return 0; -} -device_initcall(ptdump_init); |