diff options
Diffstat (limited to 'mm/ptdump.c')
| -rw-r--r-- | mm/ptdump.c | 132 |
1 files changed, 95 insertions, 37 deletions
diff --git a/mm/ptdump.c b/mm/ptdump.c index ba88ec43ff21..973020000096 100644 --- a/mm/ptdump.c +++ b/mm/ptdump.c @@ -1,10 +1,12 @@ // SPDX-License-Identifier: GPL-2.0 #include <linux/pagewalk.h> +#include <linux/debugfs.h> #include <linux/ptdump.h> #include <linux/kasan.h> +#include "internal.h" -#ifdef CONFIG_KASAN +#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) /* * This is an optimization for KASAN=y case. Since all kasan page tables * eventually point to the kasan_early_shadow_page we could call note_page() @@ -17,7 +19,7 @@ static inline int note_kasan_page_table(struct mm_walk *walk, { struct ptdump_state *st = walk->private; - st->note_page(st, addr, 4, pte_val(kasan_early_shadow_pte[0])); + st->note_page_pte(st, addr, kasan_early_shadow_pte[0]); walk->action = ACTION_CONTINUE; @@ -29,18 +31,21 @@ static int ptdump_pgd_entry(pgd_t *pgd, unsigned long addr, unsigned long next, struct mm_walk *walk) { struct ptdump_state *st = walk->private; - pgd_t val = READ_ONCE(*pgd); + pgd_t val = pgdp_get(pgd); -#if CONFIG_PGTABLE_LEVELS > 4 && defined(CONFIG_KASAN) +#if CONFIG_PGTABLE_LEVELS > 4 && \ + (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) if (pgd_page(val) == virt_to_page(lm_alias(kasan_early_shadow_p4d))) return note_kasan_page_table(walk, addr); #endif - if (st->effective_prot) - st->effective_prot(st, 0, pgd_val(val)); + if (st->effective_prot_pgd) + st->effective_prot_pgd(st, val); - if (pgd_leaf(val)) - st->note_page(st, addr, 0, pgd_val(val)); + if (pgd_leaf(val)) { + st->note_page_pgd(st, addr, val); + walk->action = ACTION_CONTINUE; + } return 0; } @@ -49,18 +54,21 @@ static int ptdump_p4d_entry(p4d_t *p4d, unsigned long addr, unsigned long next, struct mm_walk *walk) { struct ptdump_state *st = walk->private; - p4d_t val = READ_ONCE(*p4d); + p4d_t val = p4dp_get(p4d); -#if CONFIG_PGTABLE_LEVELS > 3 && defined(CONFIG_KASAN) +#if CONFIG_PGTABLE_LEVELS > 3 && \ + (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) if (p4d_page(val) == virt_to_page(lm_alias(kasan_early_shadow_pud))) return note_kasan_page_table(walk, addr); #endif - if (st->effective_prot) - st->effective_prot(st, 1, p4d_val(val)); + if (st->effective_prot_p4d) + st->effective_prot_p4d(st, val); - if (p4d_leaf(val)) - st->note_page(st, addr, 1, p4d_val(val)); + if (p4d_leaf(val)) { + st->note_page_p4d(st, addr, val); + walk->action = ACTION_CONTINUE; + } return 0; } @@ -69,18 +77,21 @@ static int ptdump_pud_entry(pud_t *pud, unsigned long addr, unsigned long next, struct mm_walk *walk) { struct ptdump_state *st = walk->private; - pud_t val = READ_ONCE(*pud); + pud_t val = pudp_get(pud); -#if CONFIG_PGTABLE_LEVELS > 2 && defined(CONFIG_KASAN) +#if CONFIG_PGTABLE_LEVELS > 2 && \ + (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) if (pud_page(val) == virt_to_page(lm_alias(kasan_early_shadow_pmd))) return note_kasan_page_table(walk, addr); #endif - if (st->effective_prot) - st->effective_prot(st, 2, pud_val(val)); + if (st->effective_prot_pud) + st->effective_prot_pud(st, val); - if (pud_leaf(val)) - st->note_page(st, addr, 2, pud_val(val)); + if (pud_leaf(val)) { + st->note_page_pud(st, addr, val); + walk->action = ACTION_CONTINUE; + } return 0; } @@ -89,17 +100,19 @@ static int ptdump_pmd_entry(pmd_t *pmd, unsigned long addr, unsigned long next, struct mm_walk *walk) { struct ptdump_state *st = walk->private; - pmd_t val = READ_ONCE(*pmd); + pmd_t val = pmdp_get(pmd); -#if defined(CONFIG_KASAN) +#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS) if (pmd_page(val) == virt_to_page(lm_alias(kasan_early_shadow_pte))) return note_kasan_page_table(walk, addr); #endif - if (st->effective_prot) - st->effective_prot(st, 3, pmd_val(val)); - if (pmd_leaf(val)) - st->note_page(st, addr, 3, pmd_val(val)); + if (st->effective_prot_pmd) + st->effective_prot_pmd(st, val); + if (pmd_leaf(val)) { + st->note_page_pmd(st, addr, val); + walk->action = ACTION_CONTINUE; + } return 0; } @@ -108,12 +121,12 @@ static int ptdump_pte_entry(pte_t *pte, unsigned long addr, unsigned long next, struct mm_walk *walk) { struct ptdump_state *st = walk->private; - pte_t val = READ_ONCE(*pte); + pte_t val = ptep_get(pte); - if (st->effective_prot) - st->effective_prot(st, 4, pte_val(val)); + if (st->effective_prot_pte) + st->effective_prot_pte(st, val); - st->note_page(st, addr, 4, pte_val(val)); + st->note_page_pte(st, addr, val); return 0; } @@ -122,9 +135,31 @@ static int ptdump_hole(unsigned long addr, unsigned long next, int depth, struct mm_walk *walk) { struct ptdump_state *st = walk->private; - - st->note_page(st, addr, depth, 0); - + pte_t pte_zero = {0}; + pmd_t pmd_zero = {0}; + pud_t pud_zero = {0}; + p4d_t p4d_zero = {0}; + pgd_t pgd_zero = {0}; + + switch (depth) { + case 4: + st->note_page_pte(st, addr, pte_zero); + break; + case 3: + st->note_page_pmd(st, addr, pmd_zero); + break; + case 2: + st->note_page_pud(st, addr, pud_zero); + break; + case 1: + st->note_page_p4d(st, addr, p4d_zero); + break; + case 0: + st->note_page_pgd(st, addr, pgd_zero); + break; + default: + break; + } return 0; } @@ -141,14 +176,37 @@ void ptdump_walk_pgd(struct ptdump_state *st, struct mm_struct *mm, pgd_t *pgd) { const struct ptdump_range *range = st->range; - mmap_read_lock(mm); + get_online_mems(); + mmap_write_lock(mm); while (range->start != range->end) { - walk_page_range_novma(mm, range->start, range->end, + walk_page_range_debug(mm, range->start, range->end, &ptdump_ops, pgd, st); range++; } - mmap_read_unlock(mm); + mmap_write_unlock(mm); + put_online_mems(); /* Flush out the last page */ - st->note_page(st, 0, -1, 0); + st->note_page_flush(st); } + +static int check_wx_show(struct seq_file *m, void *v) +{ + if (ptdump_check_wx()) + seq_puts(m, "SUCCESS\n"); + else + seq_puts(m, "FAILED\n"); + + return 0; +} + +DEFINE_SHOW_ATTRIBUTE(check_wx); + +static int ptdump_debugfs_init(void) +{ + debugfs_create_file("check_wx_pages", 0400, NULL, NULL, &check_wx_fops); + + return 0; +} + +device_initcall(ptdump_debugfs_init); |