libupnp crashes with musl 1.1.20+

[diizzyy]

libupnp crashes with musl 1.1.20+

Hi,

I think that the problem is that libupnp is calling pthread_detach() on a thread which was created in the detached state (and not pthread_join() as the comment above writes). In ThreadPool.c around line 648:

	ithread_attr_init(&attr);
	ithread_attr_setstacksize(&attr, tp->attr.stackSize);
	ithread_attr_setdetachstate(&attr, ITHREAD_CREATE_DETACHED);
	rc = ithread_create(&temp, &attr, WorkerThread, tp);
	ithread_attr_destroy(&attr);
	if (rc == 0) {
		rc = ithread_detach(temp);
		/* ithread_detach will return EINVAL if thread has been
		 successfully detached by ithread_create */
		if (rc == EINVAL)
			rc = 0;

I don't see the point of the supplementary ithread_detach() (if there is one they should have added a comment :) )

According to the man page:

       Attempting to detach an already detached thread results in unspecified behavior.

So I think that it would be reasonable to just get rid of the ithread_detach() call and the following lines.