Segfault when freeing a method

[Julien ÉLIE]

Hi,

I see that readers.conf handles group blocks like:

group {
  hosts: "*"

  auth test {
    python_auth: "script"
  }

  auth test2 {
    perl_auth: "/path/to/script.pl"
    key: "test"
  }
}


but when I play with it, I sometimes obtain:
*** glibc detected *** double free or corruption (out): 0xb7afd4f8 ***



It comes from here:

typedef struct _METHOD {
    char *name;
    char *program;
    int  type;          /* type of auth (perl, python or external) */
    char *users;        /* only used for auth_methods, not for res_methods. */
    char **extra_logs;
} METHOD;

static void
free_method(METHOD *del)
{
    if (del->program)
        free(del->program);
    free(del->name);
    free(del);
}

gdb shows me that del->name is an empty string (del->name[0] = '\0').
It sefaults when it is freed.
del->name comes from a previous xstrdup() during copy_method().
However, even if I put "if (del->name)" or "if (del->name != NULL)",
it is also freed and segfaults...

--> What is the condition to put for it not to be freed?
    I believe I should not put (*del->name != NULL), shouldn't I?
    Otherwise, it is the whole file which has a problem...

-- 
Julien ÉLIE

« Les idées fausses ne sont pas toujours mauvaises. » (Marcel Aymé)