[Spice-devel] [PATCH server v2 05/13] red-channel: send marshaller message fd

[Marc-André Lureau]

Hi

On Fri, Jan 15, 2016 at 11:44 AM, Frediano Ziglio <fziglio at redhat.com> wrote:
>>
>> From: Marc-André Lureau <mlureau at redhat.com>
>>
>> Send the fd associated to the last message sent.
>>
>> Even if the fd is invalid, the sendfd msg is appended to the protocol,
>> for 2 reasons:
>> - trying to send an invalid fd does not have to close the connection (it
>>   would with an invalid fd)
>> - even if the fd is invalid, the protocol expects an extra byte for the
>>   ancillary data
>>
>> Signed-off-by: Marc-André Lureau <marcandre.lureau at gmail.com>
>> ---
>>  server/red-channel.c | 16 ++++++++++++++++
>>  1 file changed, 16 insertions(+)
>>
>> diff --git a/server/red-channel.c b/server/red-channel.c
>> index 306c87d..b33c91d 100644
>> --- a/server/red-channel.c
>> +++ b/server/red-channel.c
>> @@ -608,8 +608,24 @@ static inline void
>> red_channel_client_release_sent_item(RedChannelClient *rcc)
>>  static void red_channel_peer_on_out_msg_done(void *opaque)
>>  {
>>      RedChannelClient *rcc = (RedChannelClient *)opaque;
>> +    int fd = spice_marshaller_get_fd(rcc->send_data.marshaller);
>>
>>      rcc->send_data.size = 0;
>> +
>> +    if (fd != -1) {
>> +        if (fcntl(fd, F_GETFD) == -1) {
>
> Is not clear what's the reason for this test.
> Why should fail?

It should not fail, but if the caller has set an invalid fd (or it
became invalid), I think it is better to deal with it and not
disconnect the client. (trying to send an invalid fd over sendmsg
closes the connection)

>
>> +            close(fd);
>> +            fd = -1;
>> +        }
>> +
>> +        if (reds_stream_send_msgfd(rcc->stream, fd) < 0) {
>> +            perror("sendfd");
>> +            red_channel_client_disconnect(rcc);
>> +            return;
>
> I think here you should close the file descriptor too to avoid leak.
>

agreed

>> +        }
>> +        close(fd);
>> +    }
>> +
>>      red_channel_client_release_sent_item(rcc);
>>      if (rcc->send_data.blocked) {
>>          rcc->send_data.blocked = FALSE;
>> --
>> 2.5.0
>>
>>
>
> Frediano



-- 
Marc-André Lureau