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This rule is only applicable in cases where the character data may contain values that can be interpreted as negative values. For example, if the char type is represented by a two's complement 8-bit value, any character value greater than +127 is interpreted as a negative value.
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Noncompliant Code Example
This non-compliant noncompliant code example is taken from a vulnerability in bash versions 1.14.6 and earlier that resulted in the release of CERT Advisory CA-1996-22. This vulnerability resulted from the sign extension of character data referenced by the string pointer in the yy_string_get() function in the parse.y module of the bash source code:
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The LDRA tool suite V 7.6.0 is able to can detect violations of this rule.
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