Commit 32749085 authored by Yang Tse's avatar Yang Tse
Browse files

avoid a couple of potential zero size memory allocations

parent c7309344

ares/CHANGES

+2 −0
Original line number Diff line number Diff line
@@ -2,6 +2,8 @@ 


* November 6



- Yang Tse removed a couple of potential zero size memory allocations.



- Andreas Rieke fixed the line endings in the areslib.dsp file that I (Daniel)

  broke in the 1.3.2 release. We should switch to a system where that file is

  auto-generated. We could rip some code for that from curl...

ares/ares_cancel.c

+5 −2
Original line number Diff line number Diff line
@@ -38,8 +38,11 @@ void ares_cancel(ares_channel channel) 
  }

  channel->queries = NULL;

  if (!(channel->flags & ARES_FLAG_STAYOPEN))

  {

    if (channel->servers)

    {

      for (i = 0; i < channel->nservers; i++)

        ares__close_sockets(channel, &channel->servers[i]);

    }

  }

}

ares/ares_destroy.c

+28 −14
Original line number Diff line number Diff line
@@ -25,23 +25,37 @@ void ares_destroy(ares_channel channel) 
  int i;

  struct query *query;



  if (!channel)

    return;



  if (channel->servers) {

    for (i = 0; i < channel->nservers; i++)

      ares__close_sockets(channel, &channel->servers[i]);

    free(channel->servers);

  }



  if (channel->domains) {

    for (i = 0; i < channel->ndomains; i++)

      free(channel->domains[i]);

    free(channel->domains);

  }



  if(channel->sortlist)

    free(channel->sortlist);



  if (channel->lookups)

    free(channel->lookups);

  while (channel->queries)

    {



  while (channel->queries) {

    query = channel->queries;

    channel->queries = query->next;

    query->callback(query->arg, ARES_EDESTRUCTION, NULL, 0);

    if (query->tcpbuf)

      free(query->tcpbuf);

    if (query->skip_server)

      free(query->skip_server);

    free(query);

  }



  free(channel);

}

ares/ares_init.c

+35 −19
Original line number Diff line number Diff line
@@ -125,7 +125,9 @@ int ares_init_options(ares_channel *channelptr, struct ares_options *options, 
  channel->queries = NULL;

  channel->domains = NULL;

  channel->sortlist = NULL;

  channel->servers = NULL;

  channel->sock_state_cb = NULL;

  channel->sock_state_cb_data = NULL;



  /* Initialize configuration by each of the four sources, from highest

   * precedence to lowest.
@@ -140,7 +142,7 @@ int ares_init_options(ares_channel *channelptr, struct ares_options *options, 
  if (status != ARES_SUCCESS)

    {

      /* Something failed; clean up memory we may have allocated. */

      if (channel->nservers != -1)

      if (channel->servers)

        free(channel->servers);

      if (channel->domains)

        {
@@ -213,13 +215,17 @@ static int init_by_options(ares_channel channel, struct ares_options *options, 


  /* Copy the servers, if given. */

  if ((optmask & ARES_OPT_SERVERS) && channel->nservers == -1)

    {

      /* Avoid zero size allocations at any cost */

      if (options->nservers > 0)

        {

          channel->servers =

            malloc(options->nservers * sizeof(struct server_state));

      if (!channel->servers && options->nservers != 0)

          if (!channel->servers)

            return ARES_ENOMEM;

          for (i = 0; i < options->nservers; i++)

            channel->servers[i].addr = options->servers[i];

        }

      channel->nservers = options->nservers;

    }
@@ -227,9 +233,12 @@ static int init_by_options(ares_channel channel, struct ares_options *options, 
   * we can clean up in case of error.

   */

  if ((optmask & ARES_OPT_DOMAINS) && channel->ndomains == -1)

    {

      /* Avoid zero size allocations at any cost */

      if (options->ndomains > 0)

      {

        channel->domains = malloc(options->ndomains * sizeof(char *));

      if (!channel->domains && options->ndomains != 0)

        if (!channel->domains)

          return ARES_ENOMEM;

        for (i = 0; i < options->ndomains; i++)

          {
@@ -238,6 +247,7 @@ static int init_by_options(ares_channel channel, struct ares_options *options, 
            if (!channel->domains[i])

              return ARES_ENOMEM;

          }

      }

      channel->ndomains = options->ndomains;

    }
@@ -711,7 +721,6 @@ static int init_by_defaults(ares_channel channel) 
      if (gethostname(hostname, sizeof(hostname)) == -1

          || !strchr(hostname, '.'))

        {

          channel->domains = malloc(0);

          channel->ndomains = 0;

        }

      else
@@ -940,6 +949,7 @@ static int set_search(ares_channel channel, const char *str) 
    for(n=0; n < channel->ndomains; n++)

      free(channel->domains[n]);

    free(channel->domains);

    channel->domains = NULL;

    channel->ndomains = -1;

  }
@@ -955,8 +965,14 @@ static int set_search(ares_channel channel, const char *str) 
      n++;

    }



  if (!n)

    {

      channel->ndomains = 0;

      return ARES_SUCCESS;

    }



  channel->domains = malloc(n * sizeof(char *));

  if (!channel->domains && n)

  if (!channel->domains)

    return ARES_ENOMEM;



  /* Now copy the domains. */