Description: ro bind mount bypass using user namespaces
References:
 https://git.kernel.org/cgit/linux/kernel/git/ebiederm/user-namespace.git/commit/?h=for-linus&id=db181ce011e3c033328608299cd6fac06ea50130
 http://www.openwall.com/lists/oss-security/2014/08/12/6
Notes:
Bugs:
upstream: released (3.17-rc1) [a6138db815df5ee542d848318e5dae681590fccd, 07b645589dcda8b7a5249e096fece2a67556f0f4, 9566d6742852c527bf5af38af5cbb878dad75705, ffbc6f0ead47fa5a1dc9642b0331cb75c20a640e, db181ce011e3c033328608299cd6fac06ea50130]
2.6.32-upstream-stable: N/A "User namespaces not usable"
sid: released (3.16.2-2) [bugfix/all/mnt-Only-change-user-settable-mount-flags-in-remount.patch, bugfix/all/mnt-Move-the-test-for-MNT_LOCK_READONLY-from-change_.patch, bugfix/all/mnt-Correct-permission-checks-in-do_remount.patch, bugfix/all/mnt-Change-the-default-remount-atime-from-relatime-t.patch, bugfix/all/mnt-Add-tests-for-unprivileged-remount-cases-that-ha.patch]
3.2-wheezy-security: N/A "User namespaces not usable"
2.6.32-squeeze-security: N/A "User namespaces not usable"
3.2-upstream-stable: N/A "User namespaces not usable"