xdg-icon-resource does not set permissions when installing icon

When installing an icon using a command such as "sudo xdg-icon-resource install --novendor --context apps --size 256 synaesthesia.png synaesthesia", the ownership of the file created at /usr/local/share/icons/hicolor/256x256/apps/synaesthesia.png is set to root:root, but the permissions aren't changed.

I ran into this problem when installing a .desktop file and icon and finding that the icon failed to show up. The problem was that the .png file was not world readable, and so after the ownership was changed it was not readable to me anymore.

xdg-icon-resource does at least remove the setuid and setgid bits, so although I can make a copy of bash with the .png extension, install that, and run it, I can't use this to make a setuid root bash.

"sudo xdg-desktop-menu install" seems to do the same thing with the files it puts in /usr/share/applications

ProblemType: Bug
DistroRelease: Ubuntu 16.10
Package: xdg-utils 1.1.1-1ubuntu2
ProcVersionSignature: Ubuntu 4.8.0-46.49-generic 4.8.17
Uname: Linux 4.8.0-46-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia
ApportVersion: 2.20.3-0ubuntu8.2
Architecture: amd64
CurrentDesktop: XFCE
Date: Thu Apr 6 20:40:29 2017
PackageArchitecture: all
SourcePackage: xdg-utils
UpgradeStatus: Upgraded to yakkety on 2016-10-13 (175 days ago)