5615f69bc2
This patch initializes KASan shadow region's page table and memory.
There are two stage for KASan initializing:
1. At early boot stage the whole shadow region is mapped to just
one physical page (kasan_zero_page). It is finished by the function
kasan_early_init which is called by __mmap_switched(arch/arm/kernel/
head-common.S)
2. After the calling of paging_init, we use kasan_zero_page as zero
shadow for some memory that KASan does not need to track, and we
allocate a new shadow space for the other memory that KASan need to
track. These issues are finished by the function kasan_init which is
call by setup_arch.
When using KASan we also need to increase the THREAD_SIZE_ORDER
from 1 to 2 as the extra calls for shadow memory uses quite a bit
of stack.
As we need to make a temporary copy of the PGD when setting up
shadow memory we create a helpful PGD_SIZE definition for both
LPAE and non-LPAE setups.
The KASan core code unconditionally calls pud_populate() so this
needs to be changed from BUG() to do {} while (0) when building
with KASan enabled.
After the initial development by Andre Ryabinin several modifications
have been made to this code:
Abbott Liu <liuwenliang@huawei.com>
- Add support ARM LPAE: If LPAE is enabled, KASan shadow region's
mapping table need be copied in the pgd_alloc() function.
- Change kasan_pte_populate,kasan_pmd_populate,kasan_pud_populate,
kasan_pgd_populate from .meminit.text section to .init.text section.
Reported by Florian Fainelli <f.fainelli@gmail.com>
Linus Walleij <linus.walleij@linaro.org>:
- Drop the custom mainpulation of TTBR0 and just use
cpu_switch_mm() to switch the pgd table.
- Adopt to handle 4th level page tabel folding.
- Rewrite the entire page directory and page entry initialization
sequence to be recursive based on ARM64:s kasan_init.c.
Ard Biesheuvel <ardb@kernel.org>:
- Necessary underlying fixes.
- Crucial bug fixes to the memory set-up code.
Co-developed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Co-developed-by: Abbott Liu <liuwenliang@huawei.com>
Co-developed-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: kasan-dev@googlegroups.com
Cc: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Ard Biesheuvel <ardb@kernel.org> # QEMU/KVM/mach-virt/LPAE/8G
Tested-by: Florian Fainelli <f.fainelli@gmail.com> # Brahma SoCs
Tested-by: Ahmad Fatoum <a.fatoum@pengutronix.de> # i.MX6Q
Reported-by: Russell King - ARM Linux <rmk+kernel@armlinux.org.uk>
Reported-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Abbott Liu <liuwenliang@huawei.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
150 lines
3.3 KiB
C
150 lines
3.3 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* arch/arm/include/asm/pgalloc.h
|
|
*
|
|
* Copyright (C) 2000-2001 Russell King
|
|
*/
|
|
#ifndef _ASMARM_PGALLOC_H
|
|
#define _ASMARM_PGALLOC_H
|
|
|
|
#include <linux/pagemap.h>
|
|
|
|
#include <asm/domain.h>
|
|
#include <asm/pgtable-hwdef.h>
|
|
#include <asm/processor.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/tlbflush.h>
|
|
|
|
#ifdef CONFIG_MMU
|
|
|
|
#define _PAGE_USER_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER))
|
|
#define _PAGE_KERNEL_TABLE (PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL))
|
|
|
|
#ifdef CONFIG_ARM_LPAE
|
|
#define PGD_SIZE (PTRS_PER_PGD * sizeof(pgd_t))
|
|
|
|
static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
|
|
{
|
|
set_pud(pud, __pud(__pa(pmd) | PMD_TYPE_TABLE));
|
|
}
|
|
|
|
#else /* !CONFIG_ARM_LPAE */
|
|
#define PGD_SIZE (PAGE_SIZE << 2)
|
|
|
|
/*
|
|
* Since we have only two-level page tables, these are trivial
|
|
*/
|
|
#define pmd_alloc_one(mm,addr) ({ BUG(); ((pmd_t *)2); })
|
|
#define pmd_free(mm, pmd) do { } while (0)
|
|
#ifdef CONFIG_KASAN
|
|
/* The KASan core unconditionally calls pud_populate() on all architectures */
|
|
#define pud_populate(mm,pmd,pte) do { } while (0)
|
|
#else
|
|
#define pud_populate(mm,pmd,pte) BUG()
|
|
#endif
|
|
#endif /* CONFIG_ARM_LPAE */
|
|
|
|
extern pgd_t *pgd_alloc(struct mm_struct *mm);
|
|
extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
|
|
|
|
static inline void clean_pte_table(pte_t *pte)
|
|
{
|
|
clean_dcache_area(pte + PTE_HWTABLE_PTRS, PTE_HWTABLE_SIZE);
|
|
}
|
|
|
|
/*
|
|
* Allocate one PTE table.
|
|
*
|
|
* This actually allocates two hardware PTE tables, but we wrap this up
|
|
* into one table thus:
|
|
*
|
|
* +------------+
|
|
* | Linux pt 0 |
|
|
* +------------+
|
|
* | Linux pt 1 |
|
|
* +------------+
|
|
* | h/w pt 0 |
|
|
* +------------+
|
|
* | h/w pt 1 |
|
|
* +------------+
|
|
*/
|
|
|
|
#define __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL
|
|
#define __HAVE_ARCH_PTE_ALLOC_ONE
|
|
#define __HAVE_ARCH_PGD_FREE
|
|
#include <asm-generic/pgalloc.h>
|
|
|
|
static inline pte_t *
|
|
pte_alloc_one_kernel(struct mm_struct *mm)
|
|
{
|
|
pte_t *pte = __pte_alloc_one_kernel(mm);
|
|
|
|
if (pte)
|
|
clean_pte_table(pte);
|
|
|
|
return pte;
|
|
}
|
|
|
|
#ifdef CONFIG_HIGHPTE
|
|
#define PGTABLE_HIGHMEM __GFP_HIGHMEM
|
|
#else
|
|
#define PGTABLE_HIGHMEM 0
|
|
#endif
|
|
|
|
static inline pgtable_t
|
|
pte_alloc_one(struct mm_struct *mm)
|
|
{
|
|
struct page *pte;
|
|
|
|
pte = __pte_alloc_one(mm, GFP_PGTABLE_USER | PGTABLE_HIGHMEM);
|
|
if (!pte)
|
|
return NULL;
|
|
if (!PageHighMem(pte))
|
|
clean_pte_table(page_address(pte));
|
|
return pte;
|
|
}
|
|
|
|
static inline void __pmd_populate(pmd_t *pmdp, phys_addr_t pte,
|
|
pmdval_t prot)
|
|
{
|
|
pmdval_t pmdval = (pte + PTE_HWTABLE_OFF) | prot;
|
|
pmdp[0] = __pmd(pmdval);
|
|
#ifndef CONFIG_ARM_LPAE
|
|
pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
|
|
#endif
|
|
flush_pmd_entry(pmdp);
|
|
}
|
|
|
|
/*
|
|
* Populate the pmdp entry with a pointer to the pte. This pmd is part
|
|
* of the mm address space.
|
|
*
|
|
* Ensure that we always set both PMD entries.
|
|
*/
|
|
static inline void
|
|
pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
|
|
{
|
|
/*
|
|
* The pmd must be loaded with the physical address of the PTE table
|
|
*/
|
|
__pmd_populate(pmdp, __pa(ptep), _PAGE_KERNEL_TABLE);
|
|
}
|
|
|
|
static inline void
|
|
pmd_populate(struct mm_struct *mm, pmd_t *pmdp, pgtable_t ptep)
|
|
{
|
|
extern pmdval_t user_pmd_table;
|
|
pmdval_t prot;
|
|
|
|
if (__LINUX_ARM_ARCH__ >= 6 && !IS_ENABLED(CONFIG_ARM_LPAE))
|
|
prot = user_pmd_table;
|
|
else
|
|
prot = _PAGE_USER_TABLE;
|
|
|
|
__pmd_populate(pmdp, page_to_phys(ptep), prot);
|
|
}
|
|
#define pmd_pgtable(pmd) pmd_page(pmd)
|
|
|
|
#endif /* CONFIG_MMU */
|
|
|
|
#endif
|