mount ignores exec option for 'users' mounts

[Ben Kurtz]

The version of 'mount' included in Ubuntu 14.04 LTS and 12.04 LTS has a bug wherein the 'exec' option in /etc/fstab is ignored on mounts with the 'user' or 'users' options when they are mounted by root. For example:

$ grep 48tb2d /etc/fstab
labdisk.site.com:/Public4 /mnt/lab_48tb2d nfs users,exec,nosuid 0 0
$ sudo mount /mnt/lab_48tb2d
$ mount | grep 48tb2d
labdisk.site.com:/Public4 on /mnt/lab_48tb2d type nfs (rw,nosuid,nodev,noexec,addr=172.16.222.158)
$ umount /mnt/lab_48tb2d
$ mount /mnt/lab_48tb2d
$ mount | grep 48tb2d
labdisk.site.com:/Public4 on /mnt/lab_48tb2d type nfs (rw,nosuid,nodev,addr=172.16.222.158)

This bug was fixed upstream several years ago and I believe therefore doesn't affect 15.10, but seems not to have made it into the current LTS releases of ubuntu.
https://git.kernel.org/cgit/utils/util-linux/util-linux.git/commit/mount/mount.c?id=a4c0cc75ff9744299f108c259efab1bd30c8007a
https://bugzilla.redhat.com/show_bug.cgi?id=769636

System info: Ubuntu 14.04.3 LTS, util-linux 2.20.1-5.1ubuntu20.7

[Ben Kurtz (bkurtz)]

This bug appears to have been re-introduced in the re-write from stand-alone `mount` to libmount, and thus is still present in Ubuntu 16.04 LTS. Reported upstream and got a fix there (https://github.com/karelzak/util-linux/commit/3c4a3de0fcb8f21bffacfd8bdc3d6fbd683c71f5). Would love to see this incorporated in the LTS release.

[Andrew Kay (music1)]

same bug in 18.04LTS, it seems