saver_xscreensaver broken with xscreensaver version 6+

[themariusus]

My xscreensaver was a glslideshow, and because the saver_xscreensaver script calls the glslideshow binary directly it now fail with xscreensaver version 6+.

XIO:  fatal IO error 2 (No such file or directory) on X server ":0"
      after 217 requests (217 known processed) with 0 events remaining.
X connection to :0 broken (explicit kill or server shutdown).

I'm guessing xscreensaver does some magic before calling glslideshow that xsecurelock doesn't know about.

[doggodanubus]

glslideshow -debug from a terminal will show it's failing to load images. xscreensaver-getimage is supposed to be called to do that and it should pull up the picture folder but is not. I think you have to make a new root window, capture it's ID then call xscreensaver-getimage. I have no workaround. :(

[themariusus]

I switched to saver_mpv for my image slideshow. mpv has less features than glslideshow but it does the job.
I don't think I'm going to switch back to xscreensaver.
I think I'm going to mark the issue as closed.
Thank you for your input.

[divVerent]

Let's keep this issue open though as this is absolutely worth reproducing and fixing.

Screensavers that use xscreensaver-getimage are out of scope though, as they reveal screen content - the very thing xsecurelock tries to prevent.

[petersohn]

Since upgrading to xscreensaver 6, images fail to load for me too. I tried running the individual saver program (for example glslideshow or carousel) from terminal without arguments, images fail to load, although I get no error message. However, when I run it in a preview from xscreensaver-demo, the images load fine.

[ghost]

I might have similar issue with xscreensaver+xsecurelock tried using export XSECURELOCK_SAVER=saver_xscreensaver and have xscreensaver running. But when I lock the screen screensaver won't show. I selected my screen saver with xscreensaver-settings . I use xscreensaver 6.05.1-2 with xsecurelock-1.8-0-1

[razor-x]

Not sure which issue should be preferred (or new issue?): #48

I might have similar issue with xscreensaver+xsecurelock tried using export XSECURELOCK_SAVER=saver_xscreensaver and have xscreensaver running. But when I lock the screen screensaver won't show. I selected my screen saver with xscreensaver-settings . I use xscreensaver 6.05.1-2 with xsecurelock-1.8-0-1

@tuxy I just happened to be trying to get this to work today on Arch and had the same issue.

I can confirm that /usr/lib/xsecurelock/saver_xscreensaver does not exist in the package contents. I tried to build xsecurelock locally, and confirmed that even with xscreensaver installed, xsecurelock ./configure does not detect it and thus does not include saver_xscreensaver in the build. (I also tried to force it with a flag, and even though I was able to get saver_xscreensaver in the local package, xsecurelock was unable to use it, giving xsecurelock: No saver selected. Giving up.).

[divVerent]

Likely cause is a different saver location for xscreensaver 6.

[divVerent]

Still working fine on Debian for me with this version:

$ apt policy xscreensaver
xscreensaver:
  Installed: 6.02+dfsg1-2+b1
  Candidate: 6.02+dfsg1-2+b1
  Version table:
 *** 6.02+dfsg1-2+b1 500
        500 http://deb.debian.org/debian bookworm/main amd64 Packages
        100 /var/lib/dpkg/status

Maybe distro-specific? If needed, I can change the configure.ac script to detect multiple paths for savers.

[mosbasik]

I'm still experiencing the same symptoms reported in #126 (comment) :

I tried running the individual saver program (for example glslideshow or carousel) from terminal without arguments, images fail to load, although I get no error message. However, when I run it in a preview from xscreensaver-demo, the images load fine.

And to be clear, other screensavers that don't try to read images from my disk (like, say, celtic) work fine!

My environment / versions:

• Arch Linux
• xscreensaver 6.08 (2023-10-10)
• xsecurelock 1.9.0 (2023-12-19)

I think issue #48 was indeed the correct place for the comments made by the ghost and @razor-x above (which were about the missing saver_xscreensaver script). That script looks fine (it's present and executable) in my environment. This issue is about something different (namely, that the screensavers glslideshow and carousel aren't working).

@divVerent are you saying in #126 (comment) that on Debian, you are seeing that xsecurelock (via saver_xscreensaver) is able to launch glslideshow and successfully display images?

[mosbasik]

Researched a bit more. Agree with #126 (comment) that glslideshow and carousel both rely on xscreensaver-getimage to get the image data they display.

Maybe worth pointing out that xscreensaver-getimage gets the image data from one of three places according to the configs in .xscreensaver:

1. screengrabs of the display
2. frames from a video input (webcam etc) (xscreensaver-getimage-video)
3. files from disk (xscreensaver-getimage-file).

Ofc (1) is not secure and in isolation it would make sense to keep it out of scope as per #126 (comment) , but the other two seem secure enough.

If this functionality is inextricably bundled together in xscreensaver-getimage, seems like the choice is between supporting one insecure and two secure configs, or none of them. Alternatively, maybe the fact that xscreensaver-getimage-file and xscreensaver-getimage-video exist means it's possible for xsecurelock to support only (2) and/or (3) via shims of some kind.

[rdiaz02]

Still working fine on Debian for me with this version:

$ apt policy xscreensaver
xscreensaver:
  Installed: 6.02+dfsg1-2+b1
  Candidate: 6.02+dfsg1-2+b1
  Version table:
 *** 6.02+dfsg1-2+b1 500
        500 http://deb.debian.org/debian bookworm/main amd64 Packages
        100 /var/lib/dpkg/status

Maybe distro-specific? If needed, I can change the configure.ac script to detect multiple paths for savers.

It is not working for me under Debian: I get xsecurelock: No saver selected. Giving up.. Running xscreensave-demo (or xscreensaver-command -lock after starting xscreensaver) works. (I am killing the xscreensaver daemon before running xsecurelock).

$ apt policy xscreensaver
xscreensaver:
  Installed: 6.08+dfsg1-1
  Candidate: 6.08+dfsg1-1
  Version table:
     6.08+dfsg1-1+b1 300
        300 http://ftp.ch.debian.org/debian unstable/main amd64 Packages
 *** 6.08+dfsg1-1 900
        900 http://ftp.ch.debian.org/debian testing/main amd64 Packages
        900 http://deb.debian.org/debian testing/main amd64 Packages
        100 /var/lib/dpkg/status
     6.06+dfsg1-3 90
         90 http://ftp.ch.debian.org/debian stable/main amd64 Packages
         90 http://deb.debian.org/debian stable/main amd64 Packages

$ apt policy xsecurelock
xsecurelock:
  Installed: 1.9.0-1
  Candidate: 1.9.0-1
  Version table:
 *** 1.9.0-1 900
        900 http://ftp.ch.debian.org/debian testing/main amd64 Packages
        300 http://ftp.ch.debian.org/debian unstable/main amd64 Packages
        900 http://deb.debian.org/debian testing/main amd64 Packages
        100 /var/lib/dpkg/status
     1.5.1-1 90
         90 http://ftp.ch.debian.org/debian stable/main amd64 Packages
         90 http://deb.debian.org/debian stable/main amd64 Packages

[ct1n]

The Debian 12.5 xscreensaver package installs the screensavers under /usr/libexec/xscreensaver, but the xsecurelock package is configured using --with-xscreensaver=/usr/lib/xscreensaver.

I manually edited /usr/libexec/xsecurelock/saver_xscreensaver and updated the following line:

: ${XSECURELOCK_XSCREENSAVER_PATH:=/usr/libexec/xscreensaver}

[rdiaz02]

Thanks! That solved it. (Searching for it now, I see this issue has been reported: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1068662 . I should have searched for it; apologies for the noise)

[ct1n]

It wasn't there before, I filed it after posting here.

[rdiaz02]

Ah, thanks! 😅