Problem in removing nodes on a list

Question

Good night,

I’m doing a show that’s sort of a "Candy Crush" on SDL. And I needed your help to help me remove the balls from the game, which in this case are the nodes on the list.

The program is going through the game looking for the nodes that have to remove that are marked with 1 on the field defenicoes..

I hope you were more specific this time!!!

Thanks for the help!

Errorr: segmentaion fault (Core dumped)

bolhas_ligadas *remove_bolhas(bolhas_ligadas *lista,int largura,int altura){
  bolhas_ligadas *aux,*aux4;
  int i,j;
  aux=lista;
  for(j=0;j<largura;j++){

    for(i=0;i<altura;i++){

      aux4=aux->next;
      if(aux4->defenicoes.marca==1){

        aux->next=aux4->next;  
        free(aux4);   
      }

      aux=aux->next;

    }
  } 
  return lista;
}