Synopsis

A stack address is stored outside a function via a parameter.

Enabled by default

Yes

Severity/Certainty

High/Medium

Full description

The address of a local stack variable is assigned to a location supplied by the caller via a parameter. When the function ends, this memory address will become invalid. This is particularly dangerous because the application might appear to run normally, when it is in fact accessing illegal memory. This might also lead to an application crash, or data changing unpredictably. Note that this check looks for any expression referring to the store located by the parameter, so the assignment local[*parameter] = & local; will trigger the check despite being OK. This check is identical to MISRAC++2008-7-5-2_c, MISRAC++2023-6.8.3_c, MISRAC2004-17.6_d, MISRAC2012-Rule-1.3_s, MISRAC2012-Rule-18.6_d, CERT-DCL30-C_e.

Coding standards

Code examples

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

void example(int **ppx) {
  int x;
  ppx[0] = &x;  //local address
}

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

static int y = 0;
void example3(int **ppx){
  *ppx = &y;  //OK - static address
}