1 // SPDX-License-Identifier: GPL-2.0
2
3 #define DISABLE_BRANCH_PROFILING
4
5 #include <linux/kasan.h>
6 #include <linux/memblock.h>
7 #include <linux/hugetlb.h>
8
9 static int __init
kasan_init_shadow_8M(unsigned long k_start,unsigned long k_end,void * block)10 kasan_init_shadow_8M(unsigned long k_start, unsigned long k_end, void *block)
11 {
12 pmd_t *pmd = pmd_off_k(k_start);
13 unsigned long k_cur, k_next;
14
15 for (k_cur = k_start; k_cur != k_end; k_cur = k_next, pmd += 2, block += SZ_8M) {
16 pte_basic_t *new;
17
18 k_next = pgd_addr_end(k_cur, k_end);
19 k_next = pgd_addr_end(k_next, k_end);
20 if ((void *)pmd_page_vaddr(*pmd) != kasan_early_shadow_pte)
21 continue;
22
23 new = memblock_alloc(sizeof(pte_basic_t), SZ_4K);
24 if (!new)
25 return -ENOMEM;
26
27 *new = pte_val(pte_mkhuge(pfn_pte(PHYS_PFN(__pa(block)), PAGE_KERNEL)));
28
29 hugepd_populate_kernel((hugepd_t *)pmd, (pte_t *)new, PAGE_SHIFT_8M);
30 hugepd_populate_kernel((hugepd_t *)pmd + 1, (pte_t *)new, PAGE_SHIFT_8M);
31 }
32 return 0;
33 }
34
kasan_init_region(void * start,size_t size)35 int __init kasan_init_region(void *start, size_t size)
36 {
37 unsigned long k_start = (unsigned long)kasan_mem_to_shadow(start);
38 unsigned long k_end = (unsigned long)kasan_mem_to_shadow(start + size);
39 unsigned long k_cur;
40 int ret;
41 void *block;
42
43 block = memblock_alloc(k_end - k_start, SZ_8M);
44 if (!block)
45 return -ENOMEM;
46
47 if (IS_ALIGNED(k_start, SZ_8M)) {
48 kasan_init_shadow_8M(k_start, ALIGN_DOWN(k_end, SZ_8M), block);
49 k_cur = ALIGN_DOWN(k_end, SZ_8M);
50 if (k_cur == k_end)
51 goto finish;
52 } else {
53 k_cur = k_start;
54 }
55
56 ret = kasan_init_shadow_page_tables(k_start, k_end);
57 if (ret)
58 return ret;
59
60 for (; k_cur < k_end; k_cur += PAGE_SIZE) {
61 pmd_t *pmd = pmd_off_k(k_cur);
62 void *va = block + k_cur - k_start;
63 pte_t pte = pfn_pte(PHYS_PFN(__pa(va)), PAGE_KERNEL);
64
65 if (k_cur < ALIGN_DOWN(k_end, SZ_512K))
66 pte = pte_mkhuge(pte);
67
68 __set_pte_at(&init_mm, k_cur, pte_offset_kernel(pmd, k_cur), pte, 0);
69 }
70 finish:
71 flush_tlb_kernel_range(k_start, k_end);
72 return 0;
73 }
74