Re: [PATCH 2/9 v2] Introduce nat/linux-namespaces.[ch]

[Gary Benson <gbenson at redhat dot com>]

Pedro Alves wrote:
> On 04/30/2015 01:05 PM, Gary Benson wrote:
> ...
> > +   For avoidance of doubt, if the helper process receives a
> > +   message it doesn't handle it will reply with MNSH_MSG_ERROR.
> > +   If the main process receives MNSH_MSG_ERROR at any time then
> > +   it will call internal_error.  If internal_error causes the
> > +   main process to exit, the helper will notice this and also
> > +   exit.  The helper will not exit until the main process
> > +   terminates, so if the user continues through internal_error
> > +   the helper will still be there awaiting requests from the
> > +   main process.
> ...
> > +/* Mount namespace helper message types.  */
> > +
> > +enum mnsh_msg_type
> > +  {
> > +    /* An unrecoverable communication error occurred.
> 
> I think "unrecoverable" here sounds a bit confusing, as it
> contradicts the comment above that explains that the helper
> is still awaiting requests if the user decides to continue
> after internal_error.

Ok, I'll remove the "unrecoverable" and leave the rest of the
message alone.

> > +    /* A request that the helper call readlink.  The single
> > +       argument (the filename) should be passed in BUF, and
> > +       should include a terminating NUL character. The helper
> 
> Missing double-space.

Ok.

> > +static void
> > +mnsh_main (int sock)
> > +{
> > +  while (1)
> > +    {
> > +      enum mnsh_msg_type type;
> > +      int fd, int1, int2;
> > +      char buf[PATH_MAX];
> > +      ssize_t size, response = -1;
> > +
> > +      size = mnsh_recv_message (sock, &type,
> > +				&fd, &int1, &int2,
> > +				buf, sizeof (buf));
> > +
> > +      if (size >= 0 && size < sizeof (buf))
> > +	{
> > +	  switch (type)
> > +	    {
> > +	    case MNSH_REQ_SETNS:
> > +	      if (fd > 0)
> > +		response = mnsh_handle_setns (sock, fd, int1);
> > +	      break;
> > +
> > +	    case MNSH_REQ_OPEN:
> > +	      if (buf[size - 1] == '\0')
> 
> Why these  == '\0' checks?  To protect against bugs?  In
> that case, I guess this should be:

> 	      if (size > 0 && buf[size - 1] == '\0')
> 
> > +		response = mnsh_handle_open (sock, buf, int1, int2);
> > +	      break;

Yeah, that's better, I'll change it.

> And that's it.  Really all looks good to me.  :-)

Sweet :)

Thanks,
Gary

-- 
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