forked from Minki/linux
58cc6b72a2
The Device-GRE memory type is unused, so remove it and reclaim a MAIR. Cc: Christoph Hellwig <hch@lst.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Suggested-by: Catalin Marinas <catalin.marinas@arm.com> Link: https://lore.kernel.org/r/20210505180228.GA3874@arm.com Link: https://lore.kernel.org/r/20210527110319.22157-2-will@kernel.org Signed-off-by: Will Deacon <will@kernel.org>
389 lines
8.6 KiB
C
389 lines
8.6 KiB
C
// 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/ptdump.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-hwdef.h>
|
|
#include <asm/ptdump.h>
|
|
|
|
|
|
enum address_markers_idx {
|
|
PAGE_OFFSET_NR = 0,
|
|
PAGE_END_NR,
|
|
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
|
|
KASAN_START_NR,
|
|
#endif
|
|
};
|
|
|
|
static struct addr_marker address_markers[] = {
|
|
{ PAGE_OFFSET, "Linear Mapping start" },
|
|
{ 0 /* PAGE_END */, "Linear Mapping end" },
|
|
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
|
|
{ 0 /* KASAN_SHADOW_START */, "Kasan shadow start" },
|
|
{ KASAN_SHADOW_END, "Kasan shadow end" },
|
|
#endif
|
|
{ BPF_JIT_REGION_START, "BPF start" },
|
|
{ BPF_JIT_REGION_END, "BPF end" },
|
|
{ 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" },
|
|
{ VMEMMAP_START, "vmemmap start" },
|
|
{ VMEMMAP_START + VMEMMAP_SIZE, "vmemmap end" },
|
|
{ -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 ptdump_state ptdump;
|
|
struct seq_file *seq;
|
|
const struct addr_marker *marker;
|
|
unsigned long start_address;
|
|
int 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_GP,
|
|
.val = PTE_GP,
|
|
.set = "GP",
|
|
.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_NORMAL_NC),
|
|
.set = "MEM/NORMAL-NC",
|
|
}, {
|
|
.mask = PTE_ATTRINDX_MASK,
|
|
.val = PTE_ATTRINDX(MT_NORMAL),
|
|
.set = "MEM/NORMAL",
|
|
}, {
|
|
.mask = PTE_ATTRINDX_MASK,
|
|
.val = PTE_ATTRINDX(MT_NORMAL_TAGGED),
|
|
.set = "MEM/NORMAL-TAGGED",
|
|
}
|
|
};
|
|
|
|
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),
|
|
}, { /* p4d */
|
|
.name = "P4D",
|
|
.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 ptdump_state *pt_st, unsigned long addr, int level,
|
|
u64 val)
|
|
{
|
|
struct pg_state *st = container_of(pt_st, struct pg_state, ptdump);
|
|
static const char units[] = "KMGTPE";
|
|
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;
|
|
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 (st->current_prot && 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);
|
|
}
|
|
|
|
}
|
|
|
|
void ptdump_walk(struct seq_file *s, struct ptdump_info *info)
|
|
{
|
|
unsigned long end = ~0UL;
|
|
struct pg_state st;
|
|
|
|
if (info->base_addr < TASK_SIZE_64)
|
|
end = TASK_SIZE_64;
|
|
|
|
st = (struct pg_state){
|
|
.seq = s,
|
|
.marker = info->markers,
|
|
.level = -1,
|
|
.ptdump = {
|
|
.note_page = note_page,
|
|
.range = (struct ptdump_range[]){
|
|
{info->base_addr, end},
|
|
{0, 0}
|
|
}
|
|
}
|
|
};
|
|
|
|
ptdump_walk_pgd(&st.ptdump, info->mm, NULL);
|
|
}
|
|
|
|
static void __init 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},
|
|
},
|
|
.level = -1,
|
|
.check_wx = true,
|
|
.ptdump = {
|
|
.note_page = note_page,
|
|
.range = (struct ptdump_range[]) {
|
|
{PAGE_OFFSET, ~0UL},
|
|
{0, 0}
|
|
}
|
|
}
|
|
};
|
|
|
|
ptdump_walk_pgd(&st.ptdump, &init_mm, NULL);
|
|
|
|
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 __init ptdump_init(void)
|
|
{
|
|
address_markers[PAGE_END_NR].start_address = PAGE_END;
|
|
#if defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)
|
|
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);
|