Re: [review v3] Remove all loaded objects if dlopen fails, ignoring NODELETE [BZ #20839]

[Florian Weimer <fweimer@redhat.com>]

* Florian Weimer:

> +/* Mark the objects as NODELETE if required.  This is delayed until
> +   after dlopen failure is not possible, so that _dl_close can clean
> +   up objects if necessary.  */
> +static void
> +activate_nodelete (struct link_map *new, int mode)
> +{
> +  if (mode & RTLD_NODELETE || new->l_nodelete == link_map_nodelete_pending)
> +    {
> +      if (__glibc_unlikely (GLRO (dl_debug_mask) & DL_DEBUG_FILES))
> +	_dl_debug_printf ("activating NODELETE for %s [%lu]\n",
> +			  new->l_name, new->l_ns);
> +      new->l_nodelete = link_map_nodelete_active;
> +    }
> +
> +  for (unsigned int i = 0; i < new->l_searchlist.r_nlist; ++i)
> +    {
> +      struct link_map *imap = new->l_searchlist.r_list[i];
> +      if (imap->l_nodelete == link_map_nodelete_pending)
> +	{
> +	  if (__glibc_unlikely (GLRO (dl_debug_mask) & DL_DEBUG_FILES))
> +	    _dl_debug_printf ("activating NODELETE for %s [%lu]\n",
> +			      imap->l_name, imap->l_ns);
> +
> +	  /* Only new objects should have set
> +	     link_map_nodelete_pending.  Existing objects should not
> +	     have gained any new dependencies and therefore cannot
> +	     reach NODELETE status.  */
> +	  assert (!imap->l_init_called || imap->l_type != lt_loaded);

This assert is incorrect because the NODELETE markers actually go in the
other direction (from new loaded libraries to their dependencies).

I still need to write tests for this.  But I can submit a patch for the
removal of the assert immediately, if so desired.

Thanks,
Florian