linux/arch/arm64/include/asm/memory.h
Laura Abbott ca219452c6 arm64: Correctly bounds check virt_addr_valid
virt_addr_valid is supposed to return true if and only if virt_to_page
returns a valid page structure. The current macro does math on whatever
address is given and passes that to pfn_valid to verify. vmalloc and
module addresses can happen to generate a pfn that 'happens' to be
valid. Fix this by only performing the pfn_valid check on addresses that
have the potential to be valid.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-22 10:17:22 +01:00

237 lines
7.3 KiB
C

/*
* Based on arch/arm/include/asm/memory.h
*
* Copyright (C) 2000-2002 Russell King
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Note: this file should not be included by non-asm/.h files
*/
#ifndef __ASM_MEMORY_H
#define __ASM_MEMORY_H
#include <linux/compiler.h>
#include <linux/const.h>
#include <linux/types.h>
#include <asm/bug.h>
#include <asm/sizes.h>
/*
* Allow for constants defined here to be used from assembly code
* by prepending the UL suffix only with actual C code compilation.
*/
#define UL(x) _AC(x, UL)
/*
* Size of the PCI I/O space. This must remain a power of two so that
* IO_SPACE_LIMIT acts as a mask for the low bits of I/O addresses.
*/
#define PCI_IO_SIZE SZ_16M
/*
* Log2 of the upper bound of the size of a struct page. Used for sizing
* the vmemmap region only, does not affect actual memory footprint.
* We don't use sizeof(struct page) directly since taking its size here
* requires its definition to be available at this point in the inclusion
* chain, and it may not be a power of 2 in the first place.
*/
#define STRUCT_PAGE_MAX_SHIFT 6
/*
* VMEMMAP_SIZE - allows the whole linear region to be covered by
* a struct page array
*/
#define VMEMMAP_SIZE (UL(1) << (VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT))
/*
* PAGE_OFFSET - the virtual address of the start of the linear map (top
* (VA_BITS - 1))
* KIMAGE_VADDR - the virtual address of the start of the kernel image
* VA_BITS - the maximum number of bits for virtual addresses.
* VA_START - the first kernel virtual address.
* TASK_SIZE - the maximum size of a user space task.
* TASK_UNMAPPED_BASE - the lower boundary of the mmap VM area.
*/
#define VA_BITS (CONFIG_ARM64_VA_BITS)
#define VA_START (UL(0xffffffffffffffff) << VA_BITS)
#define PAGE_OFFSET (UL(0xffffffffffffffff) << (VA_BITS - 1))
#define KIMAGE_VADDR (MODULES_END)
#define MODULES_END (MODULES_VADDR + MODULES_VSIZE)
#define MODULES_VADDR (VA_START + KASAN_SHADOW_SIZE)
#define MODULES_VSIZE (SZ_128M)
#define VMEMMAP_START (PAGE_OFFSET - VMEMMAP_SIZE)
#define PCI_IO_END (VMEMMAP_START - SZ_2M)
#define PCI_IO_START (PCI_IO_END - PCI_IO_SIZE)
#define FIXADDR_TOP (PCI_IO_START - SZ_2M)
#define TASK_SIZE_64 (UL(1) << VA_BITS)
#ifdef CONFIG_COMPAT
#define TASK_SIZE_32 UL(0x100000000)
#define TASK_SIZE (test_thread_flag(TIF_32BIT) ? \
TASK_SIZE_32 : TASK_SIZE_64)
#define TASK_SIZE_OF(tsk) (test_tsk_thread_flag(tsk, TIF_32BIT) ? \
TASK_SIZE_32 : TASK_SIZE_64)
#else
#define TASK_SIZE TASK_SIZE_64
#endif /* CONFIG_COMPAT */
#define TASK_UNMAPPED_BASE (PAGE_ALIGN(TASK_SIZE / 4))
#define KERNEL_START _text
#define KERNEL_END _end
/*
* The size of the KASAN shadow region. This should be 1/8th of the
* size of the entire kernel virtual address space.
*/
#ifdef CONFIG_KASAN
#define KASAN_SHADOW_SIZE (UL(1) << (VA_BITS - 3))
#else
#define KASAN_SHADOW_SIZE (0)
#endif
/*
* Physical vs virtual RAM address space conversion. These are
* private definitions which should NOT be used outside memory.h
* files. Use virt_to_phys/phys_to_virt/__pa/__va instead.
*/
#define __virt_to_phys(x) ({ \
phys_addr_t __x = (phys_addr_t)(x); \
__x & BIT(VA_BITS - 1) ? (__x & ~PAGE_OFFSET) + PHYS_OFFSET : \
(__x - kimage_voffset); })
#define __phys_to_virt(x) ((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET)
#define __phys_to_kimg(x) ((unsigned long)((x) + kimage_voffset))
/*
* Convert a page to/from a physical address
*/
#define page_to_phys(page) (__pfn_to_phys(page_to_pfn(page)))
#define phys_to_page(phys) (pfn_to_page(__phys_to_pfn(phys)))
/*
* Memory types available.
*/
#define MT_DEVICE_nGnRnE 0
#define MT_DEVICE_nGnRE 1
#define MT_DEVICE_GRE 2
#define MT_NORMAL_NC 3
#define MT_NORMAL 4
#define MT_NORMAL_WT 5
/*
* Memory types for Stage-2 translation
*/
#define MT_S2_NORMAL 0xf
#define MT_S2_DEVICE_nGnRE 0x1
#ifdef CONFIG_ARM64_4K_PAGES
#define IOREMAP_MAX_ORDER (PUD_SHIFT)
#else
#define IOREMAP_MAX_ORDER (PMD_SHIFT)
#endif
#ifdef CONFIG_BLK_DEV_INITRD
#define __early_init_dt_declare_initrd(__start, __end) \
do { \
initrd_start = (__start); \
initrd_end = (__end); \
} while (0)
#endif
#ifndef __ASSEMBLY__
#include <linux/bitops.h>
#include <linux/mmdebug.h>
extern s64 memstart_addr;
/* PHYS_OFFSET - the physical address of the start of memory. */
#define PHYS_OFFSET ({ VM_BUG_ON(memstart_addr & 1); memstart_addr; })
/* the virtual base of the kernel image (minus TEXT_OFFSET) */
extern u64 kimage_vaddr;
/* the offset between the kernel virtual and physical mappings */
extern u64 kimage_voffset;
/*
* Allow all memory at the discovery stage. We will clip it later.
*/
#define MIN_MEMBLOCK_ADDR 0
#define MAX_MEMBLOCK_ADDR U64_MAX
/*
* PFNs are used to describe any physical page; this means
* PFN 0 == physical address 0.
*
* This is the PFN of the first RAM page in the kernel
* direct-mapped view. We assume this is the first page
* of RAM in the mem_map as well.
*/
#define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT)
/*
* Note: Drivers should NOT use these. They are the wrong
* translation for translating DMA addresses. Use the driver
* DMA support - see dma-mapping.h.
*/
#define virt_to_phys virt_to_phys
static inline phys_addr_t virt_to_phys(const volatile void *x)
{
return __virt_to_phys((unsigned long)(x));
}
#define phys_to_virt phys_to_virt
static inline void *phys_to_virt(phys_addr_t x)
{
return (void *)(__phys_to_virt(x));
}
/*
* Drivers should NOT use these either.
*/
#define __pa(x) __virt_to_phys((unsigned long)(x))
#define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x)))
#define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
#define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys(x))
/*
* virt_to_page(k) convert a _valid_ virtual address to struct page *
* virt_addr_valid(k) indicates whether a virtual address is valid
*/
#define ARCH_PFN_OFFSET ((unsigned long)PHYS_PFN_OFFSET)
#ifndef CONFIG_SPARSEMEM_VMEMMAP
#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
#define _virt_addr_valid(kaddr) pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
#else
#define __virt_to_pgoff(kaddr) (((u64)(kaddr) & ~PAGE_OFFSET) / PAGE_SIZE * sizeof(struct page))
#define __page_to_voff(kaddr) (((u64)(page) & ~VMEMMAP_START) * PAGE_SIZE / sizeof(struct page))
#define page_to_virt(page) ((void *)((__page_to_voff(page)) | PAGE_OFFSET))
#define virt_to_page(vaddr) ((struct page *)((__virt_to_pgoff(vaddr)) | VMEMMAP_START))
#define _virt_addr_valid(kaddr) pfn_valid((((u64)(kaddr) & ~PAGE_OFFSET) \
+ PHYS_OFFSET) >> PAGE_SHIFT)
#endif
#endif
#define _virt_addr_is_linear(kaddr) (((u64)(kaddr)) >= PAGE_OFFSET)
#define virt_addr_valid(kaddr) (_virt_addr_is_linear(kaddr) && \
_virt_addr_valid(kaddr))
#include <asm-generic/memory_model.h>
#endif