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IAR Embedded Workbench for RISC-V 3.40

MISRAC2012-Rule-18.1_d

In this section:
Synopsis

(Required) A pointer resulting from arithmetic on a pointer operand shall address an element of the same array as that pointer operand

Enabled by default

Yes

Severity/Certainty

Medium/Medium

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Full description

A pointer to an array is potentially used outside the array bounds. This check is identical to ARR-inv-index-ptr-pos, MISRAC++2008-5-0-16_f, CERT-ARR30-C_d.

Coding standards
CERT ARR33-C

Guarantee that copies are made into storage of sufficient size

CWE 119

Improper Restriction of Operations within the Bounds of a Memory Buffer

CWE 120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

CWE 121

Stack-based Buffer Overflow

CWE 122

Heap-based Buffer Overflow

CWE 124

Buffer Underwrite ('Buffer Underflow')

CWE 126

Buffer Over-read

CWE 127

Buffer Under-read

CWE 129

Improper Validation of Array Index

MISRA C:2012 Rule-18.1

(Required) A pointer resulting from arithmetic on a pointer operand shall address an element of the same array as that pointer operand

MISRA C++ 2008 5-0-16

(Required) A pointer operand and any pointer resulting from pointer arithmetic using that operand shall both address elements of the same array.

Code examples

The following code example fails the check and will give a warning:

void example(int b) {
  int arr[10];
  int *p = arr;
  int x = (b<10 ? 8 : 11);
  p[x];
}

The following code example passes the check and will not give a warning about this issue:

void example(int b) {
  int arr[12];
  int *p = arr;
  int x = (b<10 ? 8 : 11);
  p[x];
}