This was fixed in initramfs-tools version 0.123 which is available in Zesty and later releases. The fix should be SRU'ed to both Ubuntu 14.04 and Ubuntu 16.04 which are affected. Here's a link to the commit which fixed this:
https://anonscm.debian.org/cgit/kernel/initramfs- tools.git/commit/?id=ac6d31fc2c707b72ff8af9944c9b4f8af303a6a3 ** Also affects: initramfs-tools (Ubuntu Trusty) Importance: Undecided Status: New ** Also affects: initramfs-tools (Ubuntu Xenial) Importance: Undecided Status: New ** Changed in: initramfs-tools (Ubuntu) Status: Confirmed => Fix Released ** Changed in: initramfs-tools (Ubuntu Trusty) Importance: Undecided => High ** Changed in: initramfs-tools (Ubuntu Xenial) Importance: Undecided => High ** Changed in: initramfs-tools (Ubuntu Trusty) Status: New => Triaged ** Changed in: initramfs-tools (Ubuntu Xenial) Status: New => Triaged -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to initramfs-tools in Ubuntu. https://bugs.launchpad.net/bugs/1713004 Title: Temporary files left under /var/tmp by mkinitramfs Status in initramfs-tools package in Ubuntu: Fix Released Status in initramfs-tools source package in Trusty: Triaged Status in initramfs-tools source package in Xenial: Triaged Status in initramfs-tools package in Debian: Fix Released Bug description: I recently ran out of disk space on my / mount. While looking for what consumed the disk I noticed a large number (130) of directories with names / paths beginning /var/tmp/mkinitramfs. These directories seem to be either ~103 MB or ~927 MB in size. Many of these files are months old, some are almost a year. Having had a quick look about for an explanation as to why these files are here and found Debian Bug #814345. That explains that temporary files are left behind by the initramfs-tools if something fails in the process. If this is the cause of my files then updating the Ubuntu package to version 0.123 should resolve this issue. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: initramfs-tools 0.122ubuntu8.8 ProcVersionSignature: Ubuntu 4.4.0-72.93-generic 4.4.49 Uname: Linux 4.4.0-72-generic x86_64 ApportVersion: 2.20.1-0ubuntu2.10 Architecture: amd64 CurrentDesktop: Unity Date: Fri Aug 25 09:40:41 2017 InstallationDate: Installed on 2015-03-12 (896 days ago) InstallationMedia: Ubuntu 14.04.2 LTS "Trusty Tahr" - Release amd64 (20150218.1) PackageArchitecture: all SourcePackage: initramfs-tools UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/initramfs-tools/+bug/1713004/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
