2018-12-28 08:31:14 +00:00
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// SPDX-License-Identifier: GPL-2.0
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2015-08-13 05:37:24 +00:00
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/*
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2020-12-22 20:00:28 +00:00
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* This file contains KASAN shadow initialization code.
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2015-08-13 05:37:24 +00:00
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*
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* Copyright (c) 2015 Samsung Electronics Co., Ltd.
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* Author: Andrey Ryabinin <ryabinin.a.a@gmail.com>
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*/
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2018-10-30 22:09:49 +00:00
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#include <linux/memblock.h>
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2015-08-13 05:37:24 +00:00
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#include <linux/init.h>
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#include <linux/kasan.h>
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#include <linux/kernel.h>
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2017-01-10 21:35:44 +00:00
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#include <linux/mm.h>
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2015-08-13 05:37:24 +00:00
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#include <linux/pfn.h>
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2018-08-17 22:47:04 +00:00
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#include <linux/slab.h>
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2015-08-13 05:37:24 +00:00
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#include <asm/page.h>
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#include <asm/pgalloc.h>
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2018-08-17 22:47:04 +00:00
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#include "kasan.h"
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2015-08-13 05:37:24 +00:00
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/*
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* This page serves two purposes:
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* - It used as early shadow memory. The entire shadow region populated
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* with this page, before we will be able to setup normal shadow memory.
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* - Latter it reused it as zero shadow to cover large ranges of memory
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* that allowed to access, but not handled by kasan (vmalloc/vmemmap ...).
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*/
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2018-12-28 08:30:01 +00:00
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unsigned char kasan_early_shadow_page[PAGE_SIZE] __page_aligned_bss;
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2015-08-13 05:37:24 +00:00
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2017-03-09 14:24:07 +00:00
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#if CONFIG_PGTABLE_LEVELS > 4
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2018-12-28 08:30:01 +00:00
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p4d_t kasan_early_shadow_p4d[MAX_PTRS_PER_P4D] __page_aligned_bss;
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2018-08-17 22:47:04 +00:00
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static inline bool kasan_p4d_table(pgd_t pgd)
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{
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2018-12-28 08:30:01 +00:00
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return pgd_page(pgd) == virt_to_page(lm_alias(kasan_early_shadow_p4d));
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2018-08-17 22:47:04 +00:00
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}
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#else
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static inline bool kasan_p4d_table(pgd_t pgd)
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{
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2019-03-05 23:41:31 +00:00
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return false;
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2018-08-17 22:47:04 +00:00
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}
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2017-03-09 14:24:07 +00:00
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#endif
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2015-08-13 05:37:24 +00:00
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#if CONFIG_PGTABLE_LEVELS > 3
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2018-12-28 08:30:01 +00:00
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pud_t kasan_early_shadow_pud[PTRS_PER_PUD] __page_aligned_bss;
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2018-08-17 22:47:04 +00:00
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static inline bool kasan_pud_table(p4d_t p4d)
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{
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2018-12-28 08:30:01 +00:00
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return p4d_page(p4d) == virt_to_page(lm_alias(kasan_early_shadow_pud));
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2018-08-17 22:47:04 +00:00
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}
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#else
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static inline bool kasan_pud_table(p4d_t p4d)
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{
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2019-03-05 23:41:31 +00:00
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return false;
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2018-08-17 22:47:04 +00:00
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}
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2015-08-13 05:37:24 +00:00
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#endif
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#if CONFIG_PGTABLE_LEVELS > 2
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2018-12-28 08:30:01 +00:00
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pmd_t kasan_early_shadow_pmd[PTRS_PER_PMD] __page_aligned_bss;
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2018-08-17 22:47:04 +00:00
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static inline bool kasan_pmd_table(pud_t pud)
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{
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2018-12-28 08:30:01 +00:00
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return pud_page(pud) == virt_to_page(lm_alias(kasan_early_shadow_pmd));
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2018-08-17 22:47:04 +00:00
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}
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#else
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static inline bool kasan_pmd_table(pud_t pud)
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{
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2019-03-05 23:41:31 +00:00
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return false;
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2018-08-17 22:47:04 +00:00
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}
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2015-08-13 05:37:24 +00:00
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#endif
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2021-01-12 23:49:14 +00:00
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pte_t kasan_early_shadow_pte[PTRS_PER_PTE + PTE_HWTABLE_PTRS]
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__page_aligned_bss;
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2015-08-13 05:37:24 +00:00
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2018-08-17 22:47:04 +00:00
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static inline bool kasan_pte_table(pmd_t pmd)
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{
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2018-12-28 08:30:01 +00:00
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return pmd_page(pmd) == virt_to_page(lm_alias(kasan_early_shadow_pte));
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2018-08-17 22:47:04 +00:00
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}
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2018-12-28 08:30:01 +00:00
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static inline bool kasan_early_shadow_page_entry(pte_t pte)
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2018-08-17 22:47:04 +00:00
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{
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2018-12-28 08:30:01 +00:00
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return pte_page(pte) == virt_to_page(lm_alias(kasan_early_shadow_page));
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2018-08-17 22:47:04 +00:00
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}
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2015-08-13 05:37:24 +00:00
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static __init void *early_alloc(size_t size, int node)
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{
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2019-03-12 06:30:31 +00:00
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void *ptr = memblock_alloc_try_nid(size, size, __pa(MAX_DMA_ADDRESS),
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MEMBLOCK_ALLOC_ACCESSIBLE, node);
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if (!ptr)
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panic("%s: Failed to allocate %zu bytes align=%zx nid=%d from=%llx\n",
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__func__, size, size, node, (u64)__pa(MAX_DMA_ADDRESS));
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return ptr;
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2015-08-13 05:37:24 +00:00
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}
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2018-08-17 22:47:04 +00:00
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static void __ref zero_pte_populate(pmd_t *pmd, unsigned long addr,
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2015-08-13 05:37:24 +00:00
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unsigned long end)
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{
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pte_t *pte = pte_offset_kernel(pmd, addr);
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pte_t zero_pte;
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2018-12-28 08:30:01 +00:00
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zero_pte = pfn_pte(PFN_DOWN(__pa_symbol(kasan_early_shadow_page)),
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PAGE_KERNEL);
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2015-08-13 05:37:24 +00:00
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zero_pte = pte_wrprotect(zero_pte);
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while (addr + PAGE_SIZE <= end) {
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set_pte_at(&init_mm, addr, pte, zero_pte);
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addr += PAGE_SIZE;
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pte = pte_offset_kernel(pmd, addr);
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}
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}
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2018-08-17 22:47:04 +00:00
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static int __ref zero_pmd_populate(pud_t *pud, unsigned long addr,
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2015-08-13 05:37:24 +00:00
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unsigned long end)
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{
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pmd_t *pmd = pmd_offset(pud, addr);
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unsigned long next;
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do {
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next = pmd_addr_end(addr, end);
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if (IS_ALIGNED(addr, PMD_SIZE) && end - addr >= PMD_SIZE) {
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2018-12-28 08:30:01 +00:00
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pmd_populate_kernel(&init_mm, pmd,
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lm_alias(kasan_early_shadow_pte));
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2015-08-13 05:37:24 +00:00
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continue;
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}
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if (pmd_none(*pmd)) {
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2018-08-17 22:47:04 +00:00
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pte_t *p;
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if (slab_is_available())
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mm: treewide: remove unused address argument from pte_alloc functions
Patch series "Add support for fast mremap".
This series speeds up the mremap(2) syscall by copying page tables at
the PMD level even for non-THP systems. There is concern that the extra
'address' argument that mremap passes to pte_alloc may do something
subtle architecture related in the future that may make the scheme not
work. Also we find that there is no point in passing the 'address' to
pte_alloc since its unused. This patch therefore removes this argument
tree-wide resulting in a nice negative diff as well. Also ensuring
along the way that the enabled architectures do not do anything funky
with the 'address' argument that goes unnoticed by the optimization.
Build and boot tested on x86-64. Build tested on arm64. The config
enablement patch for arm64 will be posted in the future after more
testing.
The changes were obtained by applying the following Coccinelle script.
(thanks Julia for answering all Coccinelle questions!).
Following fix ups were done manually:
* Removal of address argument from pte_fragment_alloc
* Removal of pte_alloc_one_fast definitions from m68k and microblaze.
// Options: --include-headers --no-includes
// Note: I split the 'identifier fn' line, so if you are manually
// running it, please unsplit it so it runs for you.
virtual patch
@pte_alloc_func_def depends on patch exists@
identifier E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
type T2;
@@
fn(...
- , T2 E2
)
{ ... }
@pte_alloc_func_proto_noarg depends on patch exists@
type T1, T2, T3, T4;
identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@
(
- T3 fn(T1, T2);
+ T3 fn(T1);
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- T3 fn(T1, T2, T4);
+ T3 fn(T1, T2);
)
@pte_alloc_func_proto depends on patch exists@
identifier E1, E2, E4;
type T1, T2, T3, T4;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@
(
- T3 fn(T1 E1, T2 E2);
+ T3 fn(T1 E1);
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- T3 fn(T1 E1, T2 E2, T4 E4);
+ T3 fn(T1 E1, T2 E2);
)
@pte_alloc_func_call depends on patch exists@
expression E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@
fn(...
-, E2
)
@pte_alloc_macro depends on patch exists@
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
identifier a, b, c;
expression e;
position p;
@@
(
- #define fn(a, b, c) e
+ #define fn(a, b) e
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- #define fn(a, b) e
+ #define fn(a) e
)
Link: http://lkml.kernel.org/r/20181108181201.88826-2-joelaf@google.com
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Suggested-by: Kirill A. Shutemov <kirill@shutemov.name>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-03 23:28:34 +00:00
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p = pte_alloc_one_kernel(&init_mm);
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2018-08-17 22:47:04 +00:00
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else
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p = early_alloc(PAGE_SIZE, NUMA_NO_NODE);
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if (!p)
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return -ENOMEM;
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pmd_populate_kernel(&init_mm, pmd, p);
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2015-08-13 05:37:24 +00:00
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}
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zero_pte_populate(pmd, addr, next);
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} while (pmd++, addr = next, addr != end);
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2018-08-17 22:47:04 +00:00
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return 0;
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2015-08-13 05:37:24 +00:00
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}
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2018-08-17 22:47:04 +00:00
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static int __ref zero_pud_populate(p4d_t *p4d, unsigned long addr,
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2015-08-13 05:37:24 +00:00
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unsigned long end)
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{
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2017-03-09 14:24:07 +00:00
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pud_t *pud = pud_offset(p4d, addr);
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2015-08-13 05:37:24 +00:00
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unsigned long next;
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do {
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next = pud_addr_end(addr, end);
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if (IS_ALIGNED(addr, PUD_SIZE) && end - addr >= PUD_SIZE) {
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pmd_t *pmd;
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2018-12-28 08:30:01 +00:00
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pud_populate(&init_mm, pud,
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lm_alias(kasan_early_shadow_pmd));
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2015-08-13 05:37:24 +00:00
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pmd = pmd_offset(pud, addr);
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2018-12-28 08:30:01 +00:00
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pmd_populate_kernel(&init_mm, pmd,
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lm_alias(kasan_early_shadow_pte));
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2015-08-13 05:37:24 +00:00
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continue;
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}
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if (pud_none(*pud)) {
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2018-08-17 22:47:04 +00:00
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pmd_t *p;
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if (slab_is_available()) {
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p = pmd_alloc(&init_mm, pud, addr);
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if (!p)
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return -ENOMEM;
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} else {
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pud_populate(&init_mm, pud,
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early_alloc(PAGE_SIZE, NUMA_NO_NODE));
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}
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2015-08-13 05:37:24 +00:00
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}
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zero_pmd_populate(pud, addr, next);
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} while (pud++, addr = next, addr != end);
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2018-08-17 22:47:04 +00:00
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return 0;
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2015-08-13 05:37:24 +00:00
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}
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2018-08-17 22:47:04 +00:00
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static int __ref zero_p4d_populate(pgd_t *pgd, unsigned long addr,
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2017-03-09 14:24:07 +00:00
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unsigned long end)
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{
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p4d_t *p4d = p4d_offset(pgd, addr);
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unsigned long next;
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do {
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next = p4d_addr_end(addr, end);
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2017-07-10 22:50:21 +00:00
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if (IS_ALIGNED(addr, P4D_SIZE) && end - addr >= P4D_SIZE) {
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pud_t *pud;
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pmd_t *pmd;
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2018-12-28 08:30:01 +00:00
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p4d_populate(&init_mm, p4d,
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lm_alias(kasan_early_shadow_pud));
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2017-07-10 22:50:21 +00:00
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pud = pud_offset(p4d, addr);
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2018-12-28 08:30:01 +00:00
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pud_populate(&init_mm, pud,
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lm_alias(kasan_early_shadow_pmd));
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2017-07-10 22:50:21 +00:00
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pmd = pmd_offset(pud, addr);
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pmd_populate_kernel(&init_mm, pmd,
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2018-12-28 08:30:01 +00:00
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lm_alias(kasan_early_shadow_pte));
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2017-07-10 22:50:21 +00:00
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continue;
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}
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2017-03-09 14:24:07 +00:00
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if (p4d_none(*p4d)) {
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2018-08-17 22:47:04 +00:00
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pud_t *p;
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if (slab_is_available()) {
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p = pud_alloc(&init_mm, p4d, addr);
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if (!p)
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return -ENOMEM;
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} else {
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p4d_populate(&init_mm, p4d,
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early_alloc(PAGE_SIZE, NUMA_NO_NODE));
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}
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2017-03-09 14:24:07 +00:00
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}
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zero_pud_populate(p4d, addr, next);
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} while (p4d++, addr = next, addr != end);
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2018-08-17 22:47:04 +00:00
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return 0;
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2017-03-09 14:24:07 +00:00
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}
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2015-08-13 05:37:24 +00:00
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/**
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2018-12-28 08:30:01 +00:00
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* kasan_populate_early_shadow - populate shadow memory region with
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* kasan_early_shadow_page
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2015-08-13 05:37:24 +00:00
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* @shadow_start - start of the memory range to populate
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* @shadow_end - end of the memory range to populate
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*/
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2018-12-28 08:30:01 +00:00
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int __ref kasan_populate_early_shadow(const void *shadow_start,
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const void *shadow_end)
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2015-08-13 05:37:24 +00:00
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{
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unsigned long addr = (unsigned long)shadow_start;
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unsigned long end = (unsigned long)shadow_end;
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pgd_t *pgd = pgd_offset_k(addr);
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unsigned long next;
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do {
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next = pgd_addr_end(addr, end);
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if (IS_ALIGNED(addr, PGDIR_SIZE) && end - addr >= PGDIR_SIZE) {
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2017-03-09 14:24:07 +00:00
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p4d_t *p4d;
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2015-08-13 05:37:24 +00:00
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pud_t *pud;
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pmd_t *pmd;
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/*
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2018-12-28 08:30:01 +00:00
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* kasan_early_shadow_pud should be populated with pmds
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2015-08-13 05:37:24 +00:00
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* at this moment.
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* [pud,pmd]_populate*() below needed only for
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* 3,2 - level page tables where we don't have
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* puds,pmds, so pgd_populate(), pud_populate()
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* is noops.
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*/
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2018-12-28 08:30:01 +00:00
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pgd_populate(&init_mm, pgd,
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lm_alias(kasan_early_shadow_p4d));
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2017-03-09 14:24:07 +00:00
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p4d = p4d_offset(pgd, addr);
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2018-12-28 08:30:01 +00:00
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p4d_populate(&init_mm, p4d,
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lm_alias(kasan_early_shadow_pud));
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2017-03-09 14:24:07 +00:00
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pud = pud_offset(p4d, addr);
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2018-12-28 08:30:01 +00:00
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pud_populate(&init_mm, pud,
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lm_alias(kasan_early_shadow_pmd));
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2015-08-13 05:37:24 +00:00
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pmd = pmd_offset(pud, addr);
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2018-12-28 08:30:01 +00:00
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pmd_populate_kernel(&init_mm, pmd,
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lm_alias(kasan_early_shadow_pte));
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2015-08-13 05:37:24 +00:00
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continue;
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}
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if (pgd_none(*pgd)) {
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2018-08-17 22:47:04 +00:00
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p4d_t *p;
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if (slab_is_available()) {
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p = p4d_alloc(&init_mm, pgd, addr);
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if (!p)
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return -ENOMEM;
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} else {
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pgd_populate(&init_mm, pgd,
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early_alloc(PAGE_SIZE, NUMA_NO_NODE));
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}
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2015-08-13 05:37:24 +00:00
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}
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2017-03-09 14:24:07 +00:00
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zero_p4d_populate(pgd, addr, next);
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2015-08-13 05:37:24 +00:00
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} while (pgd++, addr = next, addr != end);
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2018-08-17 22:47:04 +00:00
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return 0;
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}
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static void kasan_free_pte(pte_t *pte_start, pmd_t *pmd)
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{
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pte_t *pte;
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int i;
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for (i = 0; i < PTRS_PER_PTE; i++) {
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pte = pte_start + i;
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if (!pte_none(*pte))
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return;
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}
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pte_free_kernel(&init_mm, (pte_t *)page_to_virt(pmd_page(*pmd)));
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pmd_clear(pmd);
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}
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static void kasan_free_pmd(pmd_t *pmd_start, pud_t *pud)
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{
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pmd_t *pmd;
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int i;
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for (i = 0; i < PTRS_PER_PMD; i++) {
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pmd = pmd_start + i;
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if (!pmd_none(*pmd))
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return;
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}
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pmd_free(&init_mm, (pmd_t *)page_to_virt(pud_page(*pud)));
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pud_clear(pud);
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}
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static void kasan_free_pud(pud_t *pud_start, p4d_t *p4d)
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{
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pud_t *pud;
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int i;
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for (i = 0; i < PTRS_PER_PUD; i++) {
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pud = pud_start + i;
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if (!pud_none(*pud))
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return;
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}
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pud_free(&init_mm, (pud_t *)page_to_virt(p4d_page(*p4d)));
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p4d_clear(p4d);
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}
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static void kasan_free_p4d(p4d_t *p4d_start, pgd_t *pgd)
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{
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p4d_t *p4d;
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int i;
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for (i = 0; i < PTRS_PER_P4D; i++) {
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p4d = p4d_start + i;
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if (!p4d_none(*p4d))
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return;
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}
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p4d_free(&init_mm, (p4d_t *)page_to_virt(pgd_page(*pgd)));
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pgd_clear(pgd);
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}
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static void kasan_remove_pte_table(pte_t *pte, unsigned long addr,
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unsigned long end)
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{
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unsigned long next;
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for (; addr < end; addr = next, pte++) {
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next = (addr + PAGE_SIZE) & PAGE_MASK;
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if (next > end)
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next = end;
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if (!pte_present(*pte))
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continue;
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2018-12-28 08:30:01 +00:00
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if (WARN_ON(!kasan_early_shadow_page_entry(*pte)))
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2018-08-17 22:47:04 +00:00
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continue;
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pte_clear(&init_mm, addr, pte);
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}
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}
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static void kasan_remove_pmd_table(pmd_t *pmd, unsigned long addr,
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unsigned long end)
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{
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unsigned long next;
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for (; addr < end; addr = next, pmd++) {
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pte_t *pte;
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next = pmd_addr_end(addr, end);
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if (!pmd_present(*pmd))
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continue;
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if (kasan_pte_table(*pmd)) {
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if (IS_ALIGNED(addr, PMD_SIZE) &&
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2021-01-24 05:01:25 +00:00
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IS_ALIGNED(next, PMD_SIZE)) {
|
2018-08-17 22:47:04 +00:00
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|
pmd_clear(pmd);
|
2021-01-24 05:01:25 +00:00
|
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|
continue;
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|
}
|
2018-08-17 22:47:04 +00:00
|
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|
}
|
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|
pte = pte_offset_kernel(pmd, addr);
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|
kasan_remove_pte_table(pte, addr, next);
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|
|
kasan_free_pte(pte_offset_kernel(pmd, 0), pmd);
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|
}
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|
}
|
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|
static void kasan_remove_pud_table(pud_t *pud, unsigned long addr,
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|
unsigned long end)
|
|
|
|
{
|
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|
|
unsigned long next;
|
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|
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|
for (; addr < end; addr = next, pud++) {
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|
pmd_t *pmd, *pmd_base;
|
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|
next = pud_addr_end(addr, end);
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|
if (!pud_present(*pud))
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|
|
continue;
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|
|
if (kasan_pmd_table(*pud)) {
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|
|
|
if (IS_ALIGNED(addr, PUD_SIZE) &&
|
2021-01-24 05:01:25 +00:00
|
|
|
IS_ALIGNED(next, PUD_SIZE)) {
|
2018-08-17 22:47:04 +00:00
|
|
|
pud_clear(pud);
|
2021-01-24 05:01:25 +00:00
|
|
|
continue;
|
|
|
|
}
|
2018-08-17 22:47:04 +00:00
|
|
|
}
|
|
|
|
pmd = pmd_offset(pud, addr);
|
|
|
|
pmd_base = pmd_offset(pud, 0);
|
|
|
|
kasan_remove_pmd_table(pmd, addr, next);
|
|
|
|
kasan_free_pmd(pmd_base, pud);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
static void kasan_remove_p4d_table(p4d_t *p4d, unsigned long addr,
|
|
|
|
unsigned long end)
|
|
|
|
{
|
|
|
|
unsigned long next;
|
|
|
|
|
|
|
|
for (; addr < end; addr = next, p4d++) {
|
|
|
|
pud_t *pud;
|
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|
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|
next = p4d_addr_end(addr, end);
|
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|
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|
|
|
|
if (!p4d_present(*p4d))
|
|
|
|
continue;
|
|
|
|
|
|
|
|
if (kasan_pud_table(*p4d)) {
|
|
|
|
if (IS_ALIGNED(addr, P4D_SIZE) &&
|
2021-01-24 05:01:25 +00:00
|
|
|
IS_ALIGNED(next, P4D_SIZE)) {
|
2018-08-17 22:47:04 +00:00
|
|
|
p4d_clear(p4d);
|
2021-01-24 05:01:25 +00:00
|
|
|
continue;
|
|
|
|
}
|
2018-08-17 22:47:04 +00:00
|
|
|
}
|
|
|
|
pud = pud_offset(p4d, addr);
|
|
|
|
kasan_remove_pud_table(pud, addr, next);
|
|
|
|
kasan_free_pud(pud_offset(p4d, 0), p4d);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void kasan_remove_zero_shadow(void *start, unsigned long size)
|
|
|
|
{
|
|
|
|
unsigned long addr, end, next;
|
|
|
|
pgd_t *pgd;
|
|
|
|
|
|
|
|
addr = (unsigned long)kasan_mem_to_shadow(start);
|
|
|
|
end = addr + (size >> KASAN_SHADOW_SCALE_SHIFT);
|
|
|
|
|
2020-12-22 20:00:35 +00:00
|
|
|
if (WARN_ON((unsigned long)start % KASAN_MEMORY_PER_SHADOW_PAGE) ||
|
|
|
|
WARN_ON(size % KASAN_MEMORY_PER_SHADOW_PAGE))
|
2018-08-17 22:47:04 +00:00
|
|
|
return;
|
|
|
|
|
|
|
|
for (; addr < end; addr = next) {
|
|
|
|
p4d_t *p4d;
|
|
|
|
|
|
|
|
next = pgd_addr_end(addr, end);
|
|
|
|
|
|
|
|
pgd = pgd_offset_k(addr);
|
|
|
|
if (!pgd_present(*pgd))
|
|
|
|
continue;
|
|
|
|
|
|
|
|
if (kasan_p4d_table(*pgd)) {
|
|
|
|
if (IS_ALIGNED(addr, PGDIR_SIZE) &&
|
2021-01-24 05:01:25 +00:00
|
|
|
IS_ALIGNED(next, PGDIR_SIZE)) {
|
2018-08-17 22:47:04 +00:00
|
|
|
pgd_clear(pgd);
|
2021-01-24 05:01:25 +00:00
|
|
|
continue;
|
|
|
|
}
|
2018-08-17 22:47:04 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
p4d = p4d_offset(pgd, addr);
|
|
|
|
kasan_remove_p4d_table(p4d, addr, next);
|
|
|
|
kasan_free_p4d(p4d_offset(pgd, 0), pgd);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
int kasan_add_zero_shadow(void *start, unsigned long size)
|
|
|
|
{
|
|
|
|
int ret;
|
|
|
|
void *shadow_start, *shadow_end;
|
|
|
|
|
|
|
|
shadow_start = kasan_mem_to_shadow(start);
|
|
|
|
shadow_end = shadow_start + (size >> KASAN_SHADOW_SCALE_SHIFT);
|
|
|
|
|
2020-12-22 20:00:35 +00:00
|
|
|
if (WARN_ON((unsigned long)start % KASAN_MEMORY_PER_SHADOW_PAGE) ||
|
|
|
|
WARN_ON(size % KASAN_MEMORY_PER_SHADOW_PAGE))
|
2018-08-17 22:47:04 +00:00
|
|
|
return -EINVAL;
|
|
|
|
|
2018-12-28 08:30:01 +00:00
|
|
|
ret = kasan_populate_early_shadow(shadow_start, shadow_end);
|
2018-08-17 22:47:04 +00:00
|
|
|
if (ret)
|
2021-01-24 05:01:29 +00:00
|
|
|
kasan_remove_zero_shadow(start, size);
|
2018-08-17 22:47:04 +00:00
|
|
|
return ret;
|
2015-08-13 05:37:24 +00:00
|
|
|
}
|