2020-03-12 10:58:35 +08:00
|
|
|
// SPDX-License-Identifier: GPL-2.0-only
|
|
|
|
/*
|
|
|
|
* Copyright (C) 2019 SiFive
|
|
|
|
*/
|
|
|
|
|
2020-09-18 06:37:16 +08:00
|
|
|
#include <linux/efi.h>
|
2020-03-12 10:58:35 +08:00
|
|
|
#include <linux/init.h>
|
|
|
|
#include <linux/debugfs.h>
|
|
|
|
#include <linux/seq_file.h>
|
|
|
|
#include <linux/ptdump.h>
|
|
|
|
|
|
|
|
#include <asm/ptdump.h>
|
2020-06-09 12:32:38 +08:00
|
|
|
#include <linux/pgtable.h>
|
2020-03-12 10:58:35 +08:00
|
|
|
#include <asm/kasan.h>
|
|
|
|
|
|
|
|
#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 ptdump_state ptdump;
|
|
|
|
struct seq_file *seq;
|
|
|
|
const struct addr_marker *marker;
|
|
|
|
unsigned long start_address;
|
|
|
|
unsigned long start_pa;
|
|
|
|
unsigned long last_pa;
|
|
|
|
int level;
|
|
|
|
u64 current_prot;
|
|
|
|
bool check_wx;
|
|
|
|
unsigned long wx_pages;
|
|
|
|
};
|
|
|
|
|
|
|
|
/* Address marker */
|
|
|
|
struct addr_marker {
|
|
|
|
unsigned long start_address;
|
|
|
|
const char *name;
|
|
|
|
};
|
|
|
|
|
2020-09-18 06:37:16 +08:00
|
|
|
/* Private information for debugfs */
|
|
|
|
struct ptd_mm_info {
|
|
|
|
struct mm_struct *mm;
|
|
|
|
const struct addr_marker *markers;
|
|
|
|
unsigned long base_addr;
|
|
|
|
unsigned long end;
|
|
|
|
};
|
|
|
|
|
2021-04-12 00:41:46 +08:00
|
|
|
enum address_markers_idx {
|
|
|
|
#ifdef CONFIG_KASAN
|
|
|
|
KASAN_SHADOW_START_NR,
|
|
|
|
KASAN_SHADOW_END_NR,
|
|
|
|
#endif
|
|
|
|
FIXMAP_START_NR,
|
|
|
|
FIXMAP_END_NR,
|
|
|
|
PCI_IO_START_NR,
|
|
|
|
PCI_IO_END_NR,
|
|
|
|
#ifdef CONFIG_SPARSEMEM_VMEMMAP
|
|
|
|
VMEMMAP_START_NR,
|
|
|
|
VMEMMAP_END_NR,
|
|
|
|
#endif
|
|
|
|
VMALLOC_START_NR,
|
|
|
|
VMALLOC_END_NR,
|
|
|
|
PAGE_OFFSET_NR,
|
|
|
|
#ifdef CONFIG_64BIT
|
|
|
|
MODULES_MAPPING_NR,
|
|
|
|
KERNEL_MAPPING_NR,
|
2021-04-18 19:28:56 +08:00
|
|
|
#endif
|
2021-04-12 00:41:46 +08:00
|
|
|
END_OF_SPACE_NR
|
|
|
|
};
|
|
|
|
|
2020-03-12 10:58:35 +08:00
|
|
|
static struct addr_marker address_markers[] = {
|
|
|
|
#ifdef CONFIG_KASAN
|
2021-04-12 00:41:46 +08:00
|
|
|
{0, "Kasan shadow start"},
|
|
|
|
{0, "Kasan shadow end"},
|
2020-03-12 10:58:35 +08:00
|
|
|
#endif
|
2021-04-12 00:41:46 +08:00
|
|
|
{0, "Fixmap start"},
|
|
|
|
{0, "Fixmap end"},
|
|
|
|
{0, "PCI I/O start"},
|
|
|
|
{0, "PCI I/O end"},
|
2020-03-12 10:58:35 +08:00
|
|
|
#ifdef CONFIG_SPARSEMEM_VMEMMAP
|
2021-04-12 00:41:46 +08:00
|
|
|
{0, "vmemmap start"},
|
|
|
|
{0, "vmemmap end"},
|
|
|
|
#endif
|
|
|
|
{0, "vmalloc() area"},
|
|
|
|
{0, "vmalloc() end"},
|
|
|
|
{0, "Linear mapping"},
|
|
|
|
#ifdef CONFIG_64BIT
|
2021-06-24 20:17:21 +08:00
|
|
|
{0, "Modules/BPF mapping"},
|
|
|
|
{0, "Kernel mapping"},
|
2021-04-18 19:28:56 +08:00
|
|
|
#endif
|
2020-03-12 10:58:35 +08:00
|
|
|
{-1, NULL},
|
|
|
|
};
|
|
|
|
|
2020-09-18 06:37:16 +08:00
|
|
|
static struct ptd_mm_info kernel_ptd_info = {
|
|
|
|
.mm = &init_mm,
|
|
|
|
.markers = address_markers,
|
2021-04-12 00:41:46 +08:00
|
|
|
.base_addr = 0,
|
2020-09-18 06:37:16 +08:00
|
|
|
.end = ULONG_MAX,
|
|
|
|
};
|
|
|
|
|
|
|
|
#ifdef CONFIG_EFI
|
|
|
|
static struct addr_marker efi_addr_markers[] = {
|
|
|
|
{ 0, "UEFI runtime start" },
|
|
|
|
{ SZ_1G, "UEFI runtime end" },
|
|
|
|
{ -1, NULL }
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct ptd_mm_info efi_ptd_info = {
|
|
|
|
.mm = &efi_mm,
|
|
|
|
.markers = efi_addr_markers,
|
|
|
|
.base_addr = 0,
|
|
|
|
.end = SZ_2G,
|
|
|
|
};
|
|
|
|
#endif
|
|
|
|
|
2020-03-12 10:58:35 +08:00
|
|
|
/* Page Table Entry */
|
|
|
|
struct prot_bits {
|
|
|
|
u64 mask;
|
|
|
|
u64 val;
|
|
|
|
const char *set;
|
|
|
|
const char *clear;
|
|
|
|
};
|
|
|
|
|
|
|
|
static const struct prot_bits pte_bits[] = {
|
|
|
|
{
|
|
|
|
.mask = _PAGE_SOFT,
|
|
|
|
.val = _PAGE_SOFT,
|
|
|
|
.set = "RSW",
|
|
|
|
.clear = " ",
|
|
|
|
}, {
|
|
|
|
.mask = _PAGE_DIRTY,
|
|
|
|
.val = _PAGE_DIRTY,
|
|
|
|
.set = "D",
|
|
|
|
.clear = ".",
|
|
|
|
}, {
|
|
|
|
.mask = _PAGE_ACCESSED,
|
|
|
|
.val = _PAGE_ACCESSED,
|
|
|
|
.set = "A",
|
|
|
|
.clear = ".",
|
|
|
|
}, {
|
|
|
|
.mask = _PAGE_GLOBAL,
|
|
|
|
.val = _PAGE_GLOBAL,
|
|
|
|
.set = "G",
|
|
|
|
.clear = ".",
|
|
|
|
}, {
|
|
|
|
.mask = _PAGE_USER,
|
|
|
|
.val = _PAGE_USER,
|
|
|
|
.set = "U",
|
|
|
|
.clear = ".",
|
|
|
|
}, {
|
|
|
|
.mask = _PAGE_EXEC,
|
|
|
|
.val = _PAGE_EXEC,
|
|
|
|
.set = "X",
|
|
|
|
.clear = ".",
|
|
|
|
}, {
|
|
|
|
.mask = _PAGE_WRITE,
|
|
|
|
.val = _PAGE_WRITE,
|
|
|
|
.set = "W",
|
|
|
|
.clear = ".",
|
|
|
|
}, {
|
|
|
|
.mask = _PAGE_READ,
|
|
|
|
.val = _PAGE_READ,
|
|
|
|
.set = "R",
|
|
|
|
.clear = ".",
|
|
|
|
}, {
|
|
|
|
.mask = _PAGE_PRESENT,
|
|
|
|
.val = _PAGE_PRESENT,
|
|
|
|
.set = "V",
|
|
|
|
.clear = ".",
|
|
|
|
}
|
|
|
|
};
|
|
|
|
|
|
|
|
/* Page Level */
|
|
|
|
struct pg_level {
|
|
|
|
const char *name;
|
|
|
|
u64 mask;
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct pg_level pg_level[] = {
|
|
|
|
{ /* pgd */
|
|
|
|
.name = "PGD",
|
|
|
|
}, { /* p4d */
|
|
|
|
.name = (CONFIG_PGTABLE_LEVELS > 4) ? "P4D" : "PGD",
|
|
|
|
}, { /* pud */
|
|
|
|
.name = (CONFIG_PGTABLE_LEVELS > 3) ? "PUD" : "PGD",
|
|
|
|
}, { /* pmd */
|
|
|
|
.name = (CONFIG_PGTABLE_LEVELS > 2) ? "PMD" : "PGD",
|
|
|
|
}, { /* pte */
|
|
|
|
.name = "PTE",
|
|
|
|
},
|
|
|
|
};
|
|
|
|
|
|
|
|
static void dump_prot(struct pg_state *st)
|
|
|
|
{
|
|
|
|
unsigned int i;
|
|
|
|
|
|
|
|
for (i = 0; i < ARRAY_SIZE(pte_bits); i++) {
|
|
|
|
const char *s;
|
|
|
|
|
|
|
|
if ((st->current_prot & pte_bits[i].mask) == pte_bits[i].val)
|
|
|
|
s = pte_bits[i].set;
|
|
|
|
else
|
|
|
|
s = pte_bits[i].clear;
|
|
|
|
|
|
|
|
if (s)
|
|
|
|
pt_dump_seq_printf(st->seq, " %s", s);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
#ifdef CONFIG_64BIT
|
|
|
|
#define ADDR_FORMAT "0x%016lx"
|
|
|
|
#else
|
|
|
|
#define ADDR_FORMAT "0x%08lx"
|
|
|
|
#endif
|
|
|
|
static void dump_addr(struct pg_state *st, unsigned long addr)
|
|
|
|
{
|
|
|
|
static const char units[] = "KMGTPE";
|
|
|
|
const char *unit = units;
|
|
|
|
unsigned long delta;
|
|
|
|
|
|
|
|
pt_dump_seq_printf(st->seq, ADDR_FORMAT "-" ADDR_FORMAT " ",
|
|
|
|
st->start_address, addr);
|
|
|
|
|
|
|
|
pt_dump_seq_printf(st->seq, " " ADDR_FORMAT " ", st->start_pa);
|
|
|
|
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);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void note_prot_wx(struct pg_state *st, unsigned long addr)
|
|
|
|
{
|
|
|
|
if (!st->check_wx)
|
|
|
|
return;
|
|
|
|
|
|
|
|
if ((st->current_prot & (_PAGE_WRITE | _PAGE_EXEC)) !=
|
|
|
|
(_PAGE_WRITE | _PAGE_EXEC))
|
|
|
|
return;
|
|
|
|
|
|
|
|
WARN_ONCE(1, "riscv/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 ptdump_state *pt_st, unsigned long addr,
|
2020-06-02 12:50:01 +08:00
|
|
|
int level, u64 val)
|
2020-03-12 10:58:35 +08:00
|
|
|
{
|
|
|
|
struct pg_state *st = container_of(pt_st, struct pg_state, ptdump);
|
|
|
|
u64 pa = PFN_PHYS(pte_pfn(__pte(val)));
|
|
|
|
u64 prot = 0;
|
|
|
|
|
|
|
|
if (level >= 0)
|
|
|
|
prot = val & pg_level[level].mask;
|
|
|
|
|
|
|
|
if (st->level == -1) {
|
|
|
|
st->level = level;
|
|
|
|
st->current_prot = prot;
|
|
|
|
st->start_address = addr;
|
|
|
|
st->start_pa = pa;
|
|
|
|
st->last_pa = pa;
|
|
|
|
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) {
|
|
|
|
if (st->current_prot) {
|
|
|
|
note_prot_wx(st, addr);
|
|
|
|
dump_addr(st, addr);
|
|
|
|
dump_prot(st);
|
|
|
|
pt_dump_seq_puts(st->seq, "\n");
|
|
|
|
}
|
|
|
|
|
|
|
|
while (addr >= st->marker[1].start_address) {
|
|
|
|
st->marker++;
|
|
|
|
pt_dump_seq_printf(st->seq, "---[ %s ]---\n",
|
|
|
|
st->marker->name);
|
|
|
|
}
|
|
|
|
|
|
|
|
st->start_address = addr;
|
|
|
|
st->start_pa = pa;
|
|
|
|
st->last_pa = pa;
|
|
|
|
st->current_prot = prot;
|
|
|
|
st->level = level;
|
|
|
|
} else {
|
|
|
|
st->last_pa = pa;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2020-09-18 06:37:16 +08:00
|
|
|
static void ptdump_walk(struct seq_file *s, struct ptd_mm_info *pinfo)
|
2020-03-12 10:58:35 +08:00
|
|
|
{
|
|
|
|
struct pg_state st = {
|
|
|
|
.seq = s,
|
2020-09-18 06:37:16 +08:00
|
|
|
.marker = pinfo->markers,
|
2020-03-12 10:58:35 +08:00
|
|
|
.level = -1,
|
|
|
|
.ptdump = {
|
|
|
|
.note_page = note_page,
|
|
|
|
.range = (struct ptdump_range[]) {
|
2020-09-18 06:37:16 +08:00
|
|
|
{pinfo->base_addr, pinfo->end},
|
2020-03-12 10:58:35 +08:00
|
|
|
{0, 0}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
};
|
|
|
|
|
2020-09-18 06:37:16 +08:00
|
|
|
ptdump_walk_pgd(&st.ptdump, pinfo->mm, NULL);
|
2020-03-12 10:58:35 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
void ptdump_check_wx(void)
|
|
|
|
{
|
|
|
|
struct pg_state st = {
|
|
|
|
.seq = NULL,
|
|
|
|
.marker = (struct addr_marker[]) {
|
|
|
|
{0, NULL},
|
|
|
|
{-1, NULL},
|
|
|
|
},
|
|
|
|
.level = -1,
|
|
|
|
.check_wx = true,
|
|
|
|
.ptdump = {
|
|
|
|
.note_page = note_page,
|
|
|
|
.range = (struct ptdump_range[]) {
|
|
|
|
{KERN_VIRT_START, ULONG_MAX},
|
|
|
|
{0, 0}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
};
|
|
|
|
|
|
|
|
ptdump_walk_pgd(&st.ptdump, &init_mm, NULL);
|
|
|
|
|
|
|
|
if (st.wx_pages)
|
|
|
|
pr_warn("Checked W+X mappings: failed, %lu W+X pages found\n",
|
|
|
|
st.wx_pages);
|
|
|
|
else
|
|
|
|
pr_info("Checked W+X mappings: passed, no W+X pages found\n");
|
|
|
|
}
|
|
|
|
|
|
|
|
static int ptdump_show(struct seq_file *m, void *v)
|
|
|
|
{
|
2020-09-18 06:37:16 +08:00
|
|
|
ptdump_walk(m, m->private);
|
2020-03-12 10:58:35 +08:00
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
DEFINE_SHOW_ATTRIBUTE(ptdump);
|
|
|
|
|
2021-03-30 02:22:21 +08:00
|
|
|
static int __init ptdump_init(void)
|
2020-03-12 10:58:35 +08:00
|
|
|
{
|
|
|
|
unsigned int i, j;
|
|
|
|
|
2021-04-12 00:41:46 +08:00
|
|
|
#ifdef CONFIG_KASAN
|
|
|
|
address_markers[KASAN_SHADOW_START_NR].start_address = KASAN_SHADOW_START;
|
|
|
|
address_markers[KASAN_SHADOW_END_NR].start_address = KASAN_SHADOW_END;
|
|
|
|
#endif
|
|
|
|
address_markers[FIXMAP_START_NR].start_address = FIXADDR_START;
|
|
|
|
address_markers[FIXMAP_END_NR].start_address = FIXADDR_TOP;
|
|
|
|
address_markers[PCI_IO_START_NR].start_address = PCI_IO_START;
|
|
|
|
address_markers[PCI_IO_END_NR].start_address = PCI_IO_END;
|
|
|
|
#ifdef CONFIG_SPARSEMEM_VMEMMAP
|
|
|
|
address_markers[VMEMMAP_START_NR].start_address = VMEMMAP_START;
|
|
|
|
address_markers[VMEMMAP_END_NR].start_address = VMEMMAP_END;
|
|
|
|
#endif
|
|
|
|
address_markers[VMALLOC_START_NR].start_address = VMALLOC_START;
|
|
|
|
address_markers[VMALLOC_END_NR].start_address = VMALLOC_END;
|
|
|
|
address_markers[PAGE_OFFSET_NR].start_address = PAGE_OFFSET;
|
|
|
|
#ifdef CONFIG_64BIT
|
|
|
|
address_markers[MODULES_MAPPING_NR].start_address = MODULES_VADDR;
|
2021-06-17 21:53:07 +08:00
|
|
|
address_markers[KERNEL_MAPPING_NR].start_address = kernel_map.virt_addr;
|
2021-04-18 19:28:56 +08:00
|
|
|
#endif
|
2021-04-12 00:41:46 +08:00
|
|
|
|
|
|
|
kernel_ptd_info.base_addr = KERN_VIRT_START;
|
|
|
|
|
2020-03-12 10:58:35 +08:00
|
|
|
for (i = 0; i < ARRAY_SIZE(pg_level); i++)
|
|
|
|
for (j = 0; j < ARRAY_SIZE(pte_bits); j++)
|
|
|
|
pg_level[i].mask |= pte_bits[j].mask;
|
|
|
|
|
2020-09-18 06:37:16 +08:00
|
|
|
debugfs_create_file("kernel_page_tables", 0400, NULL, &kernel_ptd_info,
|
2020-03-12 10:58:35 +08:00
|
|
|
&ptdump_fops);
|
2020-09-18 06:37:16 +08:00
|
|
|
#ifdef CONFIG_EFI
|
|
|
|
if (efi_enabled(EFI_RUNTIME_SERVICES))
|
|
|
|
debugfs_create_file("efi_page_tables", 0400, NULL, &efi_ptd_info,
|
|
|
|
&ptdump_fops);
|
|
|
|
#endif
|
2020-03-12 10:58:35 +08:00
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
device_initcall(ptdump_init);
|