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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 | // SPDX-License-Identifier: GPL-2.0-only /// do_div() does a 64-by-32 division. /// When the divisor is long, unsigned long, u64, or s64, /// do_div() truncates it to 32 bits, this means it can test /// non-zero and be truncated to 0 for division on 64bit platforms. /// //# This makes an effort to find those inappropriate do_div() calls. // // Confidence: Moderate // Copyright: (C) 2020 Wen Yang, Alibaba. // Comments: // Options: --no-includes --include-headers virtual context virtual org virtual report @initialize:python@ @@ def get_digit_type_and_value(str): is_digit = False value = 0 try: if (str.isdigit()): is_digit = True value = int(str, 0) elif (str.upper().endswith('ULL')): is_digit = True value = int(str[:-3], 0) elif (str.upper().endswith('LL')): is_digit = True value = int(str[:-2], 0) elif (str.upper().endswith('UL')): is_digit = True value = int(str[:-2], 0) elif (str.upper().endswith('L')): is_digit = True value = int(str[:-1], 0) elif (str.upper().endswith('U')): is_digit = True value = int(str[:-1], 0) except Exception as e: print('Error:',e) is_digit = False value = 0 finally: return is_digit, value def filter_out_safe_constants(str): is_digit, value = get_digit_type_and_value(str) if (is_digit): if (value >= 0x100000000): return True else: return False else: return True def construct_warnings(suggested_fun): msg="WARNING: do_div() does a 64-by-32 division, please consider using %s instead." return msg % suggested_fun @depends on context@ expression f; long l: script:python() { filter_out_safe_constants(l) }; unsigned long ul : script:python() { filter_out_safe_constants(ul) }; u64 ul64 : script:python() { filter_out_safe_constants(ul64) }; s64 sl64 : script:python() { filter_out_safe_constants(sl64) }; @@ ( * do_div(f, l); | * do_div(f, ul); | * do_div(f, ul64); | * do_div(f, sl64); ) @r depends on (org || report)@ expression f; position p; long l: script:python() { filter_out_safe_constants(l) }; unsigned long ul : script:python() { filter_out_safe_constants(ul) }; u64 ul64 : script:python() { filter_out_safe_constants(ul64) }; s64 sl64 : script:python() { filter_out_safe_constants(sl64) }; @@ ( do_div@p(f, l); | do_div@p(f, ul); | do_div@p(f, ul64); | do_div@p(f, sl64); ) @script:python depends on org@ p << r.p; ul << r.ul; @@ coccilib.org.print_todo(p[0], construct_warnings("div64_ul")) @script:python depends on org@ p << r.p; l << r.l; @@ coccilib.org.print_todo(p[0], construct_warnings("div64_long")) @script:python depends on org@ p << r.p; ul64 << r.ul64; @@ coccilib.org.print_todo(p[0], construct_warnings("div64_u64")) @script:python depends on org@ p << r.p; sl64 << r.sl64; @@ coccilib.org.print_todo(p[0], construct_warnings("div64_s64")) @script:python depends on report@ p << r.p; ul << r.ul; @@ coccilib.report.print_report(p[0], construct_warnings("div64_ul")) @script:python depends on report@ p << r.p; l << r.l; @@ coccilib.report.print_report(p[0], construct_warnings("div64_long")) @script:python depends on report@ p << r.p; sl64 << r.sl64; @@ coccilib.report.print_report(p[0], construct_warnings("div64_s64")) @script:python depends on report@ p << r.p; ul64 << r.ul64; @@ coccilib.report.print_report(p[0], construct_warnings("div64_u64")) |