I retested using lxc-1.1.4 from the lxc-stable ppa (https://launchpad.net/~ubuntu-lxc/+archive/ubuntu/lxc-stable), which I added to a fresh VM image from the Trusty daily-builds, https://cloud- images.ubuntu.com/trusty/current.
"lxc-start -n trusty_overlay" fails as before, with the same error message, ERROR lxc_utils - utils.c:safe_mount:1641 - Permission denied - Failed to mount /home/ubuntu/test.txt onto /usr/lib/x86_64-linux-gnu/lxc/home/ubuntu/test.txt ERROR lxc_conf - conf.c:mount_entry:1731 - Permission denied - failed to mount '/home/ubuntu/test.txt' on '/usr/lib/x86_64-linux-gnu/lxc/home/ubuntu/test.txt' ERROR lxc_conf - conf.c:lxc_setup:3745 - failed to setup the mount entries for 'trusty_overlay' -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1507463 Title: OverlayFS: Wrong mnt_id and path reported in /proc in linux-3.13 Status in linux package in Ubuntu: Incomplete Status in lxc package in Ubuntu: Incomplete Bug description: I am running Ubuntu Trusty (3.13.0-65-generic #106-Ubuntu SMP Fri Oct 2 22:08:27 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux). There are two issues in OverlayFS as follows: 1. /proc/<pid>/fdinfo/<fd> reports wrong mnt_id (non-existent in /proc/<pid>/mountinfo) 2. /proc/<pid>/fd/<fd> shows incorrect path for the symlink target These issues were previously reported and patched for the Ubuntu Vivid kernel (3.19) in bug #1479468, but the patch was not applied to the 3.13 kernel, possibly because it contains an older version of overlayfs. These issues are now adversely affecting some versions of lxc when used in conjunction with the 3.13 kernel, because lxc has recently been patched to pass /proc/<pid>/fd/<fd> to the mount syscall. This change to lxc was made in response to cve-2015-1335; see bug #1476662. The kernel issues cause some overlayfs-backed containers to fail to start, with error message, strace: mount("/home/ubuntu/test.txt", "/proc/self/fd/16", 0x7ffd4c3f7fdb, MS_BIND, NULL) = -1 EACCES (Permission denied) The mount fails because /proc/self/fd/16, which should point to a file in overlayfs, has an invalid value. The version of lxc in the trusty-updates repository, lxc-1.0.7-0ubuntu0.7, is not affected. The following versions of lxc are affected: repository lxc version ---------------------------------------------------------------------------- ppa:ubuntu-lxc/lxc-git-stable-1.0 1.0.7+stable~20151014-2143-0ubuntu1~trusty ppa:ubuntu-lxc/lxc-git-stable-1.1 1.1.3+stable~20151007-2301-0ubuntu1~trusty ppa:ubuntu-lxc/lxc-git-master 1.1.3+master~20151012-0541-0ubuntu1~trusty To reproduce the lxc failure-to-start issue: # Install the 3.13 kernel and also an affected version of lxc. lxc-create -t download -n trusty -- -d ubuntu -r trusty -a amd64; touch $HOME/test.txt; echo "lxc.mount.entry = $HOME/test.txt home/ubuntu/test.txt none bind,create=file 0 0" >> $HOME/.local/share/lxc/trusty/config; lxc-clone -s -B overlayfs trusty trusty_overlay; lxc-start -n trusty_overlay; # fails to start To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1507463/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
