Division and remainder operations performed on integers are susceptible to divide-by-zero errors. Consequently, the divisor in a division or remainder operation on integer types must be checked for zero prior to the operation. Division and remainder operations performed on floating-point numbers are not subject to this rule.
Noncompliant Code Example (Division)
The result of the
/ operator is the quotient from the division of the first arithmetic operand by the second arithmetic operand. Division operations are susceptible to divide-by-zero errors. Overflow can also occur during two's-complement signed integer division when the dividend is equal to the minimum (negative) value for the signed integer type and the divisor is equal to −1 (see NUM00-J. Detect or prevent integer overflow for more information). This noncompliant code example can result in a divide-by-zero error during the division of the signed operands
Compliant Solution (Division)
This compliant solution tests the divisor to guarantee there is no possibility of divide-by-zero errors:
Noncompliant Code Example (Remainder)
% operator provides the remainder when two operands of integer type are divided. This noncompliant code example can result in a divide-by-zero error during the remainder operation on the signed operands
Compliant Solution (Remainder)
This compliant solution tests the divisor to guarantee there is no possibility of a divide-by-zero error:
A division or remainder by zero can result in abnormal program termination and denial-of-service (DoS).
|CERT.NUM02.ZERO||Avoid division by zero|
|S3518||Zero should not be a possible denominator|
CWE-369, Divide by Zero
Subclause 6.5.5, "Multiplicative Operators"
Chapter 5, "Integers"
Chapter 2, "Basics"