Comment 5 for bug 1041377

[Impact]
 * Mounts that have options that are substrings of (showthrough, optional, bootwait, nobootwait or timeout) Are
    being stripped by mountall and not being passed to the mount. Such is the case of timeo in nfs.

    The change is minimal, and simply checks that the option being stripped matches the length of option being checked against.
    This solves the case where one is a substring of the other.

[Test Case]
1. Create an nfs mount option in /etc/fstab with the timeo=2 option. Like the below.
server:/raid /raid nfs user,timeo=2,timeout=6 0 0
2. Run mountall as root
3. run mount and verify that the nfs mount specified above has the options user,timeo=2 , but not timeout=6.

[Regression Potential]
Regression potential is minimal, but regressions are most likely to manifest themselves in mount options disappearing or new options appearing (some new options appearing will be valid as is the case of timeo).