Solving abo #4

Let’s move forward, this time solving abo4.c If you have no doubts on how to solve abo3, this one will be fairly easy.

First, let’s take a look at the code:

/* abo4.c
* specially crafted to feed your brain by gera@core-sdi.com */

/* After this one, the next is just an Eureka! away */

extern system,puts;
void (*fn)(char*)=(void(*)(char*))&system;

int main(int argv,char **argc) {
char *pbuf=malloc(strlen(argc[2])+1);
char buf[256];

fn=(void(*)(char*))&puts;
strcpy(buf,argc[1]);
strcpy(pbuf,argc[2]);
fn(argc[3]);
while(1);
}