Red Hat Bugzilla – Bug 190962
/etc/mtab needs to be a symlink to /proc/mounts
Last modified: 2015-03-04 20:16:56 EST
Description of problem:
Use of the pam_namespace.so module can result in significant differences
between the /etc/mtab file reports and the state of the name-space posessed by
a user's session. If the administrator mounts or umounts a file system after
a user has logged in then /etc/mtab will be immediately updated but the actual
mount list that applies to the user will not change. This means that "df"
will produce incorrect and misleading answers.
If /etc/mtab is made a symlink to /proc/mounts then the "df" command (and
other programs that use /etc/mtab) will get the correct data that refers to
the session in question.
Also please note that pam_namespace.so provides greater benefits to non-SE
Linux users than it does to SE Linux users.
/etc/mtab and /proc/mounts don't contain identical data and different apps
work with them, so I don't think we can just merge them.
Florian La Roche