[Pkg-mpd-maintainers] Bug#738831: mpd: Mpd does not start: mpdsocket: Failed to bind to '[::]:6600': Address already in use

[Niccolo Rigacci]

Package: mpd
Version: 0.18.7-1
Severity: normal
Tags: ipv6

Dear Maintainer,

Mpd does not start properly when bind_to_address option is "any" and
you have support for both ipv4 and ipv6.

This bug seems related to #563125, but it is not a problem of the resolver,
because if you specify the following in /etc/mpd.conf:

bind_to_address         "0.0.0.0"
bind_to_address         "::"

the daemon fails to start with the error:
mpdsocket: Failed to bind to '[::]:6600': Address already in use

Instead if you start the daemon with either one of the lines, the daemon starts
binding as expected on ipv4 only

  tcp   0   0 0.0.0.0:6600   0.0.0.0:*  LISTEN

or on ipv6 only:

  tcp6  0   0 :::6600        :::*       LISTEN

So it is impossible to listen on both ipv4 and ipv6 addresses.

Here it is an strace excerpt of the fail:

socket(PF_INET, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, IPPROTO_IP) = 7
setsockopt(7, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
bind(7, {sa_family=AF_INET, sin_port=htons(6600), sin_addr=inet_addr("0.0.0.0")}, 16) = 0
listen(7, 5)                            = 0
setsockopt(7, SOL_SOCKET, SO_PASSCRED, [1], 4) = 0
socket(PF_INET6, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, IPPROTO_IP) = 8
setsockopt(8, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
bind(8, {sa_family=AF_INET6, sin6_port=htons(6600), inet_pton(AF_INET6, "::", &sin6_addr), sin6_flowinfo=0, sin6_scope_id=0}, 28) = -1 EADDRINUSE (Address already in use)


-- System Information:
Debian Release: jessie/sid
  APT prefers testing
  APT policy: (500, 'testing')
Architecture: armel (armv5tel)

Kernel: Linux 3.12-1-kirkwood
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages mpd depends on:
ii  adduser                           3.113+nmu3
ii  init-system-helpers               1.14
ii  libadplug-2.2.1-0                 2.2.1+dfsg3-0.1
ii  libao4                            1.1.0-2
ii  libasound2                        1.0.27.2-3
ii  libaudiofile1                     0.3.6-2
ii  libavahi-client3                  0.6.31-4
ii  libavahi-common3                  0.6.31-4
ii  libavcodec54                      6:9.10-2
ii  libavformat54                     6:9.10-2
ii  libavutil52                       6:9.10-2
ii  libbz2-1.0                        1.0.6-5
ii  libc6                             2.17-97
ii  libcdio-cdda1                     0.83-4.1
ii  libcdio-paranoia1                 0.83-4.1
ii  libcdio13                         0.83-4.1
ii  libcurl3-gnutls                   7.35.0-1
ii  libfaad2                          2.7-8
ii  libflac8                          1.3.0-2
ii  libfluidsynth1                    1.1.6-2
ii  libgcc1                           1:4.8.2-14
ii  libglib2.0-0                      2.36.4-1
ii  libgme0                           0.5.5-2
ii  libid3tag0                        0.15.1b-10
ii  libiso9660-8                      0.83-4.1
ii  libjack-jackd2-0 [libjack-0.116]  1.9.9.5+20130622git7de15e7a-1
ii  libmad0                           0.15.1b-8
ii  libmikmod2                        3.1.16-1
ii  libmms0                           0.6.2-3
ii  libmodplug1                       1:0.8.8.4-4
ii  libmp3lame0                       3.99.5+repack1-3
ii  libmpcdec6                        2:0.1~r459-4
ii  libmpdclient2                     2.9-1
ii  libmpg123-0                       1.16.0-1
ii  libogg0                           1.3.1-1
ii  libopenal1                        1:1.14-4
ii  libopus0                          1.1-1
ii  libpulse0                         4.0-6+b1
ii  libresid-builder0c2a              2.1.1-14
ii  libroar2                          1.0~beta11-1
ii  libsamplerate0                    0.1.8-7
ii  libshout3                         2.3.1-3
ii  libsidplay2                       2.1.1-14
ii  libsidutils0                      2.1.1-14
ii  libsndfile1                       1.0.25-9
ii  libsqlite3-0                      3.8.2-1
ii  libstdc++6                        4.8.2-14
ii  libsystemd-daemon0                204-6
ii  libvorbis0a                       1.3.2-1.3
ii  libvorbisenc2                     1.3.2-1.3
ii  libvorbisidec1                    1.0.2+svn18153-0.2
ii  libwavpack1                       4.70.0-1
ii  libwildmidi1                      0.2.3.4-2.1
ii  libwrap0                          7.6.q-25
ii  libyajl2                          2.0.4-4
ii  libzzip-0-13                      0.13.62-2
ii  lsb-base                          4.1+Debian12

mpd recommends no packages.

Versions of packages mpd suggests:
pn  avahi-daemon      <none>
pn  icecast2          <none>
ii  mpc [mpd-client]  0.25-1
pn  pulseaudio        <none>

-- Configuration Files:
/etc/mpd.conf changed:
music_directory		"/home/share/media/musica"
playlist_directory		"/var/lib/mpd/playlists"
db_file			"/var/lib/mpd/tag_cache"
log_file			"/var/log/mpd/mpd.log"
pid_file			"/run/mpd/pid"
state_file			"/var/lib/mpd/state"
sticker_file                   "/var/lib/mpd/sticker.sql"
user				"mpd"
bind_to_address		"0.0.0.0"
input {
        plugin "curl"
}
audio_output {
	type		"alsa"
	name		"My ALSA Device"
}
filesystem_charset		"UTF-8"
id3v1_encoding			"UTF-8"


-- no debconf information