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int nums[SIZE];
char *strings[SIZE];
int next_num_ptr = nums;
int free_spacebytes;

/*perform operations on next_num_ptr as array fills */

free_spacebytes = strings - next_num_ptr;

In this non-compliant code example pointer subtraction is used to determine how many free elements are left in the nums array. The first incorrect assumption is that nums and strings arrays will be next to each other in memory. The second is that free_bytes will be the number of bytes available. The subtraction will return the number of elements between next_num_ptr and strings.

Compliant Solution

nt nums[SIZE];
char *strings[SIZE];
int next_num_ptr = nums;
int free_spaceelements =SIZE;

/*perform operations on next_num_ptr as array fills 
  decrement free_spaceelements as it fills */

In the compliant solution, the number of free elements is kept as a counter and adjusted on every array operation. It is also calculated in terms of free elements instead if bytes. This prevents further mathematical errors.

Risk Assessment

Related Vulnerabilities

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