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8 | 8 | #include <linux/ratelimit.h> |
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9 | 9 | #include <linux/kasan.h> |
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10 | 10 | |
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11 | | -static bool want_page_poisoning __read_mostly; |
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| 11 | +bool _page_poisoning_enabled_early; |
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| 12 | +EXPORT_SYMBOL(_page_poisoning_enabled_early); |
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| 13 | +DEFINE_STATIC_KEY_FALSE(_page_poisoning_enabled); |
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| 14 | +EXPORT_SYMBOL(_page_poisoning_enabled); |
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12 | 15 | |
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13 | 16 | static int __init early_page_poison_param(char *buf) |
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14 | 17 | { |
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15 | | - if (!buf) |
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16 | | - return -EINVAL; |
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17 | | - return strtobool(buf, &want_page_poisoning); |
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| 18 | + return kstrtobool(buf, &_page_poisoning_enabled_early); |
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18 | 19 | } |
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19 | 20 | early_param("page_poison", early_page_poison_param); |
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20 | | - |
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21 | | -/** |
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22 | | - * page_poisoning_enabled - check if page poisoning is enabled |
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23 | | - * |
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24 | | - * Return true if page poisoning is enabled, or false if not. |
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25 | | - */ |
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26 | | -bool page_poisoning_enabled(void) |
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27 | | -{ |
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28 | | - /* |
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29 | | - * Assumes that debug_pagealloc_enabled is set before |
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30 | | - * free_all_bootmem. |
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31 | | - * Page poisoning is debug page alloc for some arches. If |
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32 | | - * either of those options are enabled, enable poisoning. |
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33 | | - */ |
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34 | | - return (want_page_poisoning || |
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35 | | - (!IS_ENABLED(CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC) && |
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36 | | - debug_pagealloc_enabled())); |
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37 | | -} |
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38 | | -EXPORT_SYMBOL_GPL(page_poisoning_enabled); |
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39 | 21 | |
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40 | 22 | static void poison_page(struct page *page) |
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41 | 23 | { |
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.. | .. |
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43 | 25 | |
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44 | 26 | /* KASAN still think the page is in-use, so skip it. */ |
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45 | 27 | kasan_disable_current(); |
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46 | | - memset(addr, PAGE_POISON, PAGE_SIZE); |
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| 28 | + memset(kasan_reset_tag(addr), PAGE_POISON, PAGE_SIZE); |
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47 | 29 | kasan_enable_current(); |
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48 | 30 | kunmap_atomic(addr); |
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49 | 31 | } |
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50 | 32 | |
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51 | | -static void poison_pages(struct page *page, int n) |
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| 33 | +void __kernel_poison_pages(struct page *page, int n) |
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52 | 34 | { |
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53 | 35 | int i; |
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54 | 36 | |
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.. | .. |
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68 | 50 | static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 10); |
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69 | 51 | unsigned char *start; |
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70 | 52 | unsigned char *end; |
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71 | | - |
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72 | | - if (IS_ENABLED(CONFIG_PAGE_POISONING_NO_SANITY)) |
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73 | | - return; |
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74 | 53 | |
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75 | 54 | start = memchr_inv(mem, PAGE_POISON, bytes); |
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76 | 55 | if (!start) |
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.. | .. |
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98 | 77 | void *addr; |
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99 | 78 | |
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100 | 79 | addr = kmap_atomic(page); |
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| 80 | + kasan_disable_current(); |
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101 | 81 | /* |
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102 | 82 | * Page poisoning when enabled poisons each and every page |
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103 | 83 | * that is freed to buddy. Thus no extra check is done to |
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104 | | - * see if a page was posioned. |
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| 84 | + * see if a page was poisoned. |
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105 | 85 | */ |
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106 | | - check_poison_mem(addr, PAGE_SIZE); |
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| 86 | + check_poison_mem(kasan_reset_tag(addr), PAGE_SIZE); |
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| 87 | + kasan_enable_current(); |
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107 | 88 | kunmap_atomic(addr); |
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108 | 89 | } |
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109 | 90 | |
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110 | | -static void unpoison_pages(struct page *page, int n) |
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| 91 | +void __kernel_unpoison_pages(struct page *page, int n) |
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111 | 92 | { |
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112 | 93 | int i; |
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113 | 94 | |
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114 | 95 | for (i = 0; i < n; i++) |
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115 | 96 | unpoison_page(page + i); |
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116 | | -} |
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117 | | - |
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118 | | -void kernel_poison_pages(struct page *page, int numpages, int enable) |
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119 | | -{ |
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120 | | - if (!page_poisoning_enabled()) |
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121 | | - return; |
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122 | | - |
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123 | | - if (enable) |
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124 | | - unpoison_pages(page, numpages); |
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125 | | - else |
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126 | | - poison_pages(page, numpages); |
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127 | 97 | } |
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128 | 98 | |
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129 | 99 | #ifndef CONFIG_ARCH_SUPPORTS_DEBUG_PAGEALLOC |
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