Integer operations must result in an integer value within the range of the integer type (that is, the resulting value is the same as the result produced by unlimited-range integers). Frequently the range is more restrictive based on the use of the integer value, for example, as an index. Integer values can be verified by code review or by static analysis.
Verifiably in range operations are often preferable to treating out of range values as an error condition because the handling of these errors has been repeatedly shown to cause denial-of-service problems in actual applications. The quintessential example of this is the failure of the Ariane 5 launcher which occurred due to an improperly handled conversion error resulting in the processor being shutdown [Lions 96].
Risk Assessment
Rule |
Severity |
Likelihood |
Remediation Cost |
Priority |
Level |
|---|---|---|---|---|---|
INT08-A |
2 (medium) |
2 (probable) |
1 (high) |
P4 |
L3 |
References
[[Lions 96]]