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Code Block
bgColor#FFCCCC
langc
#include <stdio.h>

/* Get username and password from user, return -1 on error */
extern int do_auth(void);
enum { BUFFERSIZE = 24 }; 
void report_error(const char *msg) {
  const char *error_log;
  char buffer[BUFFERSIZE];

  sprintf(buffer, "Error: %s\n", error_log);
  puts( buffer);
}

int main(void) {
  if (do_auth() == -1) {
    report_error("Unable to login");
  }
  return 0;
}

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Code Block
bgColor#ffcccc
langc
#include <stdio.h>
enum { BUFFERSIZE = 24 }; 
void report_error(const char *msg) {
  const char *error_log = msg;
  char buffer[BUFFERSIZE];

  sprintf(buffer, "Error: %s\n", error_log);
  puts( buffer);
}

This example remains problematic because a buffer overflow will occur if the null-terminated byte string referenced by msg is greater than 17 characters, including the null terminator. (See STR31-C. Guarantee that storage for strings has sufficient space for character data and the null terminator for more information.)

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