Ebooks thumbnails fail in Nemo over SMB

[roussel geoffrey]

Nemo is unable to generate ebooks thumbnails over SMB share because of evince-thumbnailer apparmor profile(note that Nautilus is able to do it anyway), i removed apparmor to see and it fixed that issue.

Nemo output when generating thumbs:
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(nemo:31811): CinnamonDesktop-WARNING **: 01:08:30.200: Error creating thumbnail for smb://akem-hp.local/comics_bds_mangas/Scrooge/Uncle%20Scrooge%20(001-100)%20GetComics.INFO/029%20Uncle%20Scrooge.cbr: Unrecognized image file format
Error loading remote document: An AppArmor policy prevents this sender from sending this message to this recipient; type="method_call", sender=":1.243" (uid=1000 pid=1488 comm="evince-thumbnailer -s 128 smb://akem-hp.local/comi" label="/usr/bin/evince-thumbnailer (enforce)") interface="org.gtk.vfs.MountTracker" member="LookupMount" error name="(unset)" requested_reply="0" destination=":1.10" (uid=1000 pid=1725 comm="/usr/lib/gvfs/gvfsd " label="unconfined")

(nemo:31811): CinnamonDesktop-WARNING **: 01:08:30.365: Unable to create loader for mime type application/x-cbr: Unrecognized image file format
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Note that it does the same with pdf or some other ebooks format.

The problem happens in loopback too, just share a folder with ebooks using SMB, flush the thumbnails and open Nemo to that folder via Network(connect to the SMB).

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: evince 3.28.4-0ubuntu1.2
ProcVersionSignature: Ubuntu 4.18.0-22.23~18.04.1-generic 4.18.20
Uname: Linux 4.18.0-22-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.5
Architecture: amd64
Date: Thu Jun 27 02:11:28 2019
InstallationDate: Installed on 2019-05-31 (26 days ago)
InstallationMedia: Ubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210)
SourcePackage: evince
UpgradeStatus: No upgrade log present (probably fresh install)

[Jamie Strandboge (jdstrand)]

(nemo:31811): CinnamonDesktop-WARNING **: 01:08:30.200: Error creating thumbnail for smb://akem-hp.local/comics_bds_mangas/Scrooge/Uncle%20Scrooge%20(001-100)%20GetComics.INFO/029%20Uncle%20Scrooge.cbr: Unrecognized image file format

This suggests that the problem is not due to the apparmor profile (it happens before the denial). Is the thumbnail correctly generated if you do: sudo apparmor_parser -R /etc/apparmor.d/usr.bin.evince (this unloads the policy from the kernel).

[roussel geoffrey (roussel-geoffrey)]

I know it looks like it does not recognise the image format,
but using this command fixes the issue, in fact i added this command to my /etc/rc.local so i can keep apparmor up and running, after that it generates all the thumbnails correctly for the differents formats of ebooks, and it doesn't display this error message anymore.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.