...
| Code Block | ||
|---|---|---|
| ||
...
char *new_secret;
size_t size = strlen(secret);
if (size == SIZE_MAX) {
/* Handle Error */
}
new_secret = calloc(size+1,sizeof(char)); /* use calloc() to zero-out allocated space */
new_secret = calloc(size+1,sizeof(char));
if (!new_secret) {
/* Handle Error */
}
strcpy(new_secret, secret);
/* Process new_secret... */
/* sanitize memory */
memset(new_secret, '\0', size); /* sanitize memory */
free(new_secret);
...
|
| Wiki Markup |
|---|
The {{calloc()}} function ensures that the newly allocated memory has also be cleared. Because {{sizeof(char)}} is guaranteed to be 1, this solution does not need to check for a numeric overflow as a result of using {{calloc()}} \[[MEM37-C | MEM37-C. Ensure that size arguments to calloc() do not result in an integer overflow]\]. |
...
| Code Block | ||
|---|---|---|
| ||
...
size_t secret_size;
...
if (secret_size > SIZE_MAX/2) {
/* handle error condition */
}
/* calloc() initializes memory to zero */
temp_buff = calloc(secret_size * 2, sizeof(char)); /* calloc() initializes memory to zero */
if (temp_buff == NULL) {
/* Handle Error */
}
memcpy(temp_buff, secret, secret_size);
/* sanitize the buffer */
memset(secret, '\0', secret_size); /* sanitize the buffer */
free(secret);
secret = temp_buff; /* install the resized buffer */
temp_buff = NULL;
...
|
...