audit: set the name_len in audit_inode for parent lookups

Currently, this gets set mostly by happenstance when we call into
audit_inode_child. While that might be a little more efficient, it seems
wrong. If the syscall ends up failing before audit_inode_child ever gets
called, then you'll have an audit_names record that shows the full path
but has the parent inode info attached.

Fix this by passing in a parent flag when we call audit_inode that gets
set to the value of LOOKUP_PARENT. We can then fix up the pathname for
the audit entry correctly from the get-go.

While we're at it, clean up the no-op macro for audit_inode in the
!CONFIG_AUDITSYSCALL case.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namei.c b/fs/namei.c
index a7ad35c..6a92d98 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1973,7 +1973,7 @@
 		retval = path_lookupat(dfd, name, flags | LOOKUP_REVAL, nd);
 
 	if (likely(!retval))
-		audit_inode(name, nd->path.dentry);
+		audit_inode(name, nd->path.dentry, flags & LOOKUP_PARENT);
 	return retval;
 }
 
@@ -2648,7 +2648,7 @@
 		error = complete_walk(nd);
 		if (error)
 			return error;
-		audit_inode(pathname, nd->path.dentry);
+		audit_inode(pathname, nd->path.dentry, 0);
 		if (open_flag & O_CREAT) {
 			error = -EISDIR;
 			goto out;
@@ -2658,7 +2658,7 @@
 		error = complete_walk(nd);
 		if (error)
 			return error;
-		audit_inode(pathname, dir);
+		audit_inode(pathname, dir, 0);
 		goto finish_open;
 	}
 
@@ -2687,7 +2687,7 @@
 		if (error)
 			return error;
 
-		audit_inode(pathname, dir);
+		audit_inode(pathname, dir, 0);
 		error = -EISDIR;
 		/* trailing slashes? */
 		if (nd->last.name[nd->last.len])
@@ -2717,7 +2717,7 @@
 		    !S_ISREG(file->f_path.dentry->d_inode->i_mode))
 			will_truncate = false;
 
-		audit_inode(pathname, file->f_path.dentry);
+		audit_inode(pathname, file->f_path.dentry, 0);
 		goto opened;
 	}
 
@@ -2734,7 +2734,7 @@
 	 * create/update audit record if it already exists.
 	 */
 	if (path->dentry->d_inode)
-		audit_inode(pathname, path->dentry);
+		audit_inode(pathname, path->dentry, 0);
 
 	/*
 	 * If atomic_open() acquired write access it is dropped now due to
@@ -2799,7 +2799,7 @@
 	error = -ENOTDIR;
 	if ((nd->flags & LOOKUP_DIRECTORY) && !nd->inode->i_op->lookup)
 		goto out;
-	audit_inode(pathname, nd->path.dentry);
+	audit_inode(pathname, nd->path.dentry, 0);
 finish_open:
 	if (!S_ISREG(nd->inode->i_mode))
 		will_truncate = false;
diff --git a/fs/open.c b/fs/open.c
index 44da0fe..a015437 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -478,7 +478,7 @@
 
 	file = fget(fd);
 	if (file) {
-		audit_inode(NULL, file->f_path.dentry);
+		audit_inode(NULL, file->f_path.dentry, 0);
 		err = chmod_common(&file->f_path, mode);
 		fput(file);
 	}
@@ -588,7 +588,7 @@
 	error = mnt_want_write_file(f.file);
 	if (error)
 		goto out_fput;
-	audit_inode(NULL, f.file->f_path.dentry);
+	audit_inode(NULL, f.file->f_path.dentry, 0);
 	error = chown_common(&f.file->f_path, user, group);
 	mnt_drop_write_file(f.file);
 out_fput:
diff --git a/fs/xattr.c b/fs/xattr.c
index 1780f06..e164ddd 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -412,7 +412,7 @@
 	if (!f.file)
 		return error;
 	dentry = f.file->f_path.dentry;
-	audit_inode(NULL, dentry);
+	audit_inode(NULL, dentry, 0);
 	error = mnt_want_write_file(f.file);
 	if (!error) {
 		error = setxattr(dentry, name, value, size, flags);
@@ -507,7 +507,7 @@
 
 	if (!f.file)
 		return error;
-	audit_inode(NULL, f.file->f_path.dentry);
+	audit_inode(NULL, f.file->f_path.dentry, 0);
 	error = getxattr(f.file->f_path.dentry, name, value, size);
 	fdput(f);
 	return error;
@@ -586,7 +586,7 @@
 
 	if (!f.file)
 		return error;
-	audit_inode(NULL, f.file->f_path.dentry);
+	audit_inode(NULL, f.file->f_path.dentry, 0);
 	error = listxattr(f.file->f_path.dentry, list, size);
 	fdput(f);
 	return error;
@@ -655,7 +655,7 @@
 	if (!f.file)
 		return error;
 	dentry = f.file->f_path.dentry;
-	audit_inode(NULL, dentry);
+	audit_inode(NULL, dentry, 0);
 	error = mnt_want_write_file(f.file);
 	if (!error) {
 		error = removexattr(dentry, name);