How to avoid long chain of free's (or deletes) after every error check in C?

Suppose I write my code very defensively and always check the return types from all the functions that I call.

So I go like:

char* function() {
    char* mem = get_memory(100);  // first allocation
    if (!mem) return NULL;

    struct binder* b = get_binder('regular binder');  // second allocation
    if (!b) {
        free(mem);
        return NULL;
    }

    struct file* f = mk_file();  // third allocation
    if (!f) {
        free(mem);
        free_binder(b);
        return NULL;
    }

    // ...
}

Notice how quickly free() things get out of control. If some of the function fails, I have to free every single allocation before. The code quickly becomes ugly and all I do is copy paste everything over. I become a copy/paste programmer, even worse, if someone adds a statement somewhere in between, he has to modify all the code below to call the free() for his addition.

How do experienced C programmers go about this problem? I can't figure anything out.

Thanks, Boda Cydo.