[PATCH] Collect more inode information during syscall processing.

This patch augments the collection of inode info during syscall
processing. It represents part of the functionality that was provided
by the auditfs patch included in RHEL4.

Specifically, it:

- Collects information for target inodes created or removed during
  syscalls.  Previous code only collects information for the target
  inode's parent.

- Adds the audit_inode() hook to syscalls that operate on a file
  descriptor (e.g. fchown), enabling audit to do inode filtering for
  these calls.

- Modifies filtering code to check audit context for either an inode #
  or a parent inode # matching a given rule.

- Modifies logging to provide inode # for both parent and child.

- Protect debug info from NULL audit_names.name.

[AV: folded a later typo fix from the same author]

Signed-off-by: Amy Griffis <amy.griffis@hp.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>