CVE request: kernel: NFS DoS related to "automount" symlinks

[Eugene Teo <eugeneteo () kernel sg>]

fix LOOKUP_FOLLOW on automount "symlinks"

"Make sure that automount "symlinks" are followed regardless of 
LOOKUP_FOLLOW; it should have no effect on them."

Upstream commit:
http://git.kernel.org/linus/ac278a9c505092dd82077a2446af8f9fc0d9c095

Note:
+ * This is a temporary kludge to deal with "automount" symlinks; proper
+ * solution is to trigger them on follow_mount(), so that do_lookup()
+ * would DTRT.  To be killed before 2.6.34-final.

This affects kernels version 2.6.18 onwards.

https://bugzilla.redhat.com/show_bug.cgi?id=567813

Thanks, Eugene