tree f3aeb2482e3a348fad2376a5f998b880956d9369
parent 6bd1d8758db278cb97989a0ebd85059fd948b73b
author Eric W. Biederman <ebiederm@xmission.com> 1473879218 -0500
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1474623091 +0200

devpts: Change the owner of /dev/pts/ptmx to the mounter of /dev/pts

In 99.99% of the cases only root in a user namespace can mount /dev/pts
and in those cases the owner of /dev/pts/ptmx will remain root.root

In the oddball case where someone else has CAP_SYS_ADMIN this code
modifies the /dev/pts mount code to use current_fsuid and current_fsgid
as the values to use when creating the /dev/ptmx inode.  As is done
when any other file is created.

This is a code simplification, and it allows running without a root
user entirely.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>