The C Standard identifies the following condition under which division and remainder operations result in undefined behavior (UB):
The value of the second operand of the
Ensure that division and remainder operations do not result in divide-by-zero errors.
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 (most negative) value for the signed integer type and the divisor is equal to
−1. (See INT32-C. Ensure that operations on signed integers do not result in overflow.)
Noncompliant Code Example
This noncompliant code example prevents signed integer overflow in compliance with INT32-C. Ensure that operations on signed integers do not result in overflow but fails to prevent a divide-by-zero error during the division of the signed operands
This compliant solution tests the division operation to guarantee there is no possibility of divide-by-zero errors or signed overflow:
The remainder operator provides the remainder when two operands of integer type are divided.
Noncompliant Code Example
This noncompliant code example prevents signed integer overflow in compliance with INT32-C. Ensure that operations on signed integers do not result in overflow but fails to prevent a divide-by-zero error during the remainder operation on the signed operands
This compliant solution tests the remainder operand to guarantee there is no possibility of a divide-by-zero error or an overflow error:
A divide-by-zero error can result in abnormal program termination and denial of service.
|Division by zero|
Float Division By Zero
Can detect some violations of this rule (In particular, it ensures that all operations involving division or modulo are preceded by a check ensuring that the second operand is nonzero.)
Context sensitive analysis of division by zero
|LDRA tool suite|
43 D, 127 D, 248 S, 629 S, 80 X
|Avoid division by zero|
|Parasoft Insure++||Runtime analysis|
|Polyspace Bug Finder|
Rule fully covered.
2830 [C], 2831 [D], 2832 [A]
2833 [S], 2834 [P]
|2831, 2832, 2833, 2834|
|SonarQube C/C++ Plugin|
Exhaustively verified (see one compliant and one non-compliant example).
Key here (explains table format and definitions)
|CERT C||INT32-C. Ensure that operations on signed integers do not result in overflow||Prior to 2018-01-12: CERT: Unspecified Relationship|
|CERT Oracle Secure Coding Standard for Java||NUM02-J. Ensure that division and remainder operations do not result in divide-by-zero errors||Prior to 2018-01-12: CERT: Unspecified Relationship|
|ISO/IEC TS 17961||Integer division errors [diverr]||Prior to 2018-01-12: CERT: Unspecified Relationship|
|CWE 2.11||CWE-369, Divide By Zero||2017-07-07: CERT: Exact|
CERT-CWE Mapping Notes
Key here for mapping notes
CWE-682 and INT33-C
CWE-682 = Union( INT33-C, list) where list =
- Incorrect calculations that do not involve division by zero