huge commit

2026/cscg/pwn/intro-pwn-2/intro-fmt.c

@@ -0,0 +1,43 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+// --------------------------------------------------- SETUP
+
+void ignore_me_init_buffering()
+{
+    setvbuf(stdin, NULL, _IONBF, 0);
+    setvbuf(stdout, NULL, _IONBF, 0);
+    setvbuf(stderr, NULL, _IONBF, 0);
+}
+
+// --------------------------------------------------- VULNERABLE FUNCTION
+
+int bug = 0;
+void vuln()
+{
+    char name[1024];
+    printf("What is your name?\n");
+    int number_read = read(STDIN_FILENO, name, sizeof(name) - 1);
+    name[number_read-1] = 0;
+    printf("Thank you ");
+    printf(name);
+    printf("!\n");
+    if(bug){
+        printf("Oh, you got here somehow, you must have triggered a bug.. Here is the flag: ");
+        system("cat /flag");
+        exit(0);
+    }
+    printf("But our flag is in another branch!\n");
+}
+
+// --------------------------------------------------- MAIN
+
+int main(int argc, char **argv)
+{
+    (void)argc;
+    (void)argv;
+    ignore_me_init_buffering();
+
+    vuln();
+}