[X2Go-User] Cannot launch GThumb (double free or corruption)

[Ulrich Sibiller]

When I start gthumb it immediately starts to scan my homedir (and
probablly more, I have not checked) for images and videos. Have tried
using a new, fresh user without any data in the home?

One question you did not answer yet: are you running Xorg or Wayland
on the client side? If Wayland then try to switch to Xorg and see if
the problem persists (or starts to appear locally).

More ideas:
>From experience I can say that Ubuntu does not always port all bug
fixes from debian. So _maybe_ it could help to try and install the
current debian package of gthumb on your system. Or you could try to
compile gthumb yourself in the most current version.

Uli

On Tue, Nov 26, 2019 at 12:47 AM Nicolas Ecarnot
<nicolas.x2go at ecarnot.net> wrote:
>
> Le 25/11/2019 à 23:13, Ulrich Sibiller a écrit :
> > Ok, that all looks fine. I have tested myself on Debian Buster and
> > Debian 8.1. No gthumb problems. So I suppose it might have to do with
> > your images.
>
> I open no images.
> I just run gthumb, with no argument nor image to show.
>
> >
> > Uli
> >
> > On Mon, Nov 25, 2019 at 3:13 PM Nicolas Ecarnot
> > <nicolas.x2go at ecarnot.net> wrote:
> >>
> >> Here are all the answers :
> >>
> >> nico at furon:~$ export MALLOC_CHECK_=0
> >> nico at furon:~$ gthumb
> >> free(): double free detected in tcache 2
> >> Abandon (core dumped)
> >> nico at furon:~$ dpkg --list|grep -i nxagent
> >> ii  libnx-x11-6:amd64                             2:3.5.99.21-3build1
> >>                 amd64        nxagent's libNX_X11 client-part library
> >> ii  nxagent                                       2:3.5.99.21-3build1
> >>                 amd64        Nested Xserver (aka NX Agent) supporting the
> >> NX compression protocol
> >>
> >> nico at furon:~$ xdpyinfo
> >> name of display:    :50.0
> >> version number:    11.0
> >> vendor string:    The X.Org Foundation
> >> vendor release number:    70000000
> >> X.Org version: 7.0.0
> >> maximum request size:  16777212 bytes
> >> motion buffer size:  256
> >> bitmap unit, bit order, padding:    32, LSBFirst, 32
> >> image byte order:    LSBFirst
> >> number of supported pixmap formats:    7
> >> supported pixmap formats:
> >>       depth 1, bits_per_pixel 1, scanline_pad 32
> >>       depth 4, bits_per_pixel 8, scanline_pad 32
> >>       depth 8, bits_per_pixel 8, scanline_pad 32
> >>       depth 15, bits_per_pixel 16, scanline_pad 32
> >>       depth 16, bits_per_pixel 16, scanline_pad 32
> >>       depth 24, bits_per_pixel 32, scanline_pad 32
> >>       depth 32, bits_per_pixel 32, scanline_pad 32
> >> keycode range:    minimum 8, maximum 255
> >> focus:  window 0x2e000ab, revert to Parent
> >> number of extensions:    23
> >>       BIG-REQUESTS
> >>       DAMAGE
> >>       DOUBLE-BUFFER
> >>       DPMS
> >>       GLX
> >>       MIT-SCREEN-SAVER
> >>       MIT-SHM
> >>       RANDR
> >>       RECORD
> >>       RENDER
> >>       SECURITY
> >>       SGI-GLX
> >>       SHAPE
> >>       SYNC
> >>       X-Resource
> >>       XC-MISC
> >>       XFIXES
> >>       XFree86-Bigfont
> >>       XINERAMA
> >>       XInputExtension
> >>       XKEYBOARD
> >>       XTEST
> >>       XVideo
> >> default screen number:    0
> >> number of screens:    1
> >>
> >> screen #0:
> >>     dimensions:    1918x1000 pixels (507x265 millimeters)
> >>     resolution:    96x96 dots per inch
> >>     depths (7):    24, 1, 4, 8, 15, 16, 32
> >>     root window id:    0x229
> >>     depth of root window:    24 planes
> >>     number of colormaps:    minimum 1, maximum 1
> >>     default colormap:    0x20d
> >>     default number of colormap cells:    256
> >>     preallocated pixels:    black 0, white 16777215
> >>     options:    backing-store YES, save-unders YES
> >>     largest cursor:    1920x1000
> >>     current input event mask:    0xfa803f
> >>       KeyPressMask             KeyReleaseMask           ButtonPressMask
> >>
> >>       ButtonReleaseMask        EnterWindowMask          LeaveWindowMask
> >>
> >>       ExposureMask             StructureNotifyMask
> >> SubstructureNotifyMask
> >>       SubstructureRedirectMask FocusChangeMask
> >> PropertyChangeMask
> >>       ColormapChangeMask
> >>     number of visuals:    8
> >>     default visual id:  0x205
> >>     visual:
> >>       visual id:    0x205
> >>       class:    TrueColor
> >>       depth:    24 planes
> >>       available colormap entries:    256 per subfield
> >>       red, green, blue masks:    0xff0000, 0xff00, 0xff
> >>       significant bits in color specification:    8 bits
> >>     visual:
> >>       visual id:    0x206
> >>       class:    TrueColor
> >>       depth:    24 planes
> >>       available colormap entries:    256 per subfield
> >>       red, green, blue masks:    0xff0000, 0xff00, 0xff
> >>       significant bits in color specification:    8 bits
> >>     visual:
> >>       visual id:    0x207
> >>       class:    TrueColor
> >>       depth:    24 planes
> >>       available colormap entries:    256 per subfield
> >>       red, green, blue masks:    0xff0000, 0xff00, 0xff
> >>       significant bits in color specification:    8 bits
> >>     visual:
> >>       visual id:    0x208
> >>       class:    TrueColor
> >>       depth:    24 planes
> >>       available colormap entries:    256 per subfield
> >>       red, green, blue masks:    0xff0000, 0xff00, 0xff
> >>       significant bits in color specification:    8 bits
> >>     visual:
> >>       visual id:    0x209
> >>       class:    DirectColor
> >>       depth:    24 planes
> >>       available colormap entries:    256 per subfield
> >>       red, green, blue masks:    0xff0000, 0xff00, 0xff
> >>       significant bits in color specification:    8 bits
> >>     visual:
> >>       visual id:    0x20a
> >>       class:    DirectColor
> >>       depth:    24 planes
> >>       available colormap entries:    256 per subfield
> >>       red, green, blue masks:    0xff0000, 0xff00, 0xff
> >>       significant bits in color specification:    8 bits
> >>     visual:
> >>       visual id:    0x20b
> >>       class:    DirectColor
> >>       depth:    24 planes
> >>       available colormap entries:    256 per subfield
> >>       red, green, blue masks:    0xff0000, 0xff00, 0xff
> >>       significant bits in color specification:    8 bits
> >>     visual:
> >>       visual id:    0x20c
> >>       class:    DirectColor
> >>       depth:    24 planes
> >>       available colormap entries:    256 per subfield
> >>       red, green, blue masks:    0xff0000, 0xff00, 0xff
> >>       significant bits in color specification:    8 bits
> >> nico at furon:~$
> >>
> >> nico at furon:~$ cat /etc/x2go/x2goagent.options
> >> #
> >> # This file can be used to specify default options that are passed to
> >> nxagent.
> >> #
> >> # These options can be overridden by the client!
> >> #
> >> # See the output of `nxagent -help` for the full list of options.
> >> #
> >> # Remember:
> >> # "-extension" disables an extension.
> >> # "+extension" enables an extension.
> >>
> >> X2GO_NXAGENT_DEFAULT_OPTIONS=""
> >>
> >> # Uncomment to disable GLX, the old mesa version is hopelessly outdated
> >> anyways.
> >> # Unbreaks the gnome3 control center
> >> #
> >> #X2GO_NXAGENT_DEFAULT_OPTIONS+=" -extension GLX"
> >>
> >> # Launch X2Go's X-server x2goagent with option "-nolisten tcp".
> >> #
> >> # This is the default setting and the X2Go developers really recommend
> >> not to
> >> # touch this. However, if you play with this (i.e. if you comment it
> >> out) you
> >> # should really know what you are doing.
> >> #
> >> # For everyone else: don't touch the line below!!!
> >> X2GO_NXAGENT_DEFAULT_OPTIONS+=" -nolisten tcp"
> >>
> >> # Enforce clipboard behaviour in X2Go sessions globally (for all
> >> connecting clients)
> >> # Possible values for the -clipboard option: both, server, client, none
> >> # If this option stays commented out, clients can choose the sessions'
> >> clipboard behaviour...
> >> #X2GO_NXAGENT_DEFAULT_OPTIONS+=" -clipboard both"
> >>
> >> # BIG-REQUESTS can be problematic. Older versions of nx-libs did not
> >> implement
> >> # this extension correctly, leading to all sorts of weird crashes if left
> >> # enabled.
> >> # Newer versions should handle this extension much better, but if you see
> >> # crashes related to BIG-REQUESTS, uncomment this line to disable the
> >> # extension.
> >> #X2GO_NXAGENT_DEFAULT_OPTIONS+=" -extension BIG-REQUESTS"
> >>
> >> # Extra nxagent nx/nx options, separated by commas.  For example: sleep=0
> >> X2GO_NXOPTIONS=""
> >>
> >>
> >> Le 25/11/2019 à 14:38, Ulrich Sibiller a écrit :
> >>> On Mon, Nov 25, 2019 at 1:49 PM Nicolas Ecarnot
> >>> <nicolas.x2go at ecarnot.net> wrote:
> >>>> I tried this, to no avail.
> >>>>
> >>>> I still don't understand why it fails while in the x2go context, and
> >>>> runs when being run locally.
> >>>>
> >>>> Are there env. params I should check / compare ?
> >>>
> >>>
> >>> This is interesting. So setting MALLOC_CHECK_=0 does not change
> >>> anything? (have you checked that you included the _ at the end of the
> >>> variable name?).
> >>>
> >>> X2go is using nxagent. nxagent is an Xserver. It is - feature-wise -
> >>> not on par with the current (local) X server you are probably using
> >>> (or maybe you are using wayland locally?). So maybe gthumb is not
> >>> correctly checking if the X server feature set is the one it expects.
> >>>
> >>> What version of nxagent are you using?
> >>>
> >>> Am I right that your X2go connection is not dying?
> >>>
> >>> Can you run xdpyinfo inside your session and post the output regarding
> >>> extensions? Can you also please post your server-side
> >>> /etc/x2go/x2goagent.options?
> >>>
> >>> Uli
> >>>
> >>
> >>
> >>
> >> --
> >> Nicolas ECARNOT
>
>
> --
> Nicolas ECARNOT