cifs: fix inode leak in cifs_get_inode_info_unix

Try this:

    mount a share with unix extensions
    create a file on it
    umount the share

You'll get the following message in the ring buffer:

VFS: Busy inodes after unmount of cifs. Self-destruct in 5 seconds.  Have a
nice day...

...the problem is that cifs_get_inode_info_unix is creating and hashing
a new inode even when it's going to return error anyway. The first
lookup when creating a file returns an error so we end up leaking this
inode before we do the actual create. This appears to be a regression
caused by commit 0e4bbde9.

The following patch seems to fix it for me, and fixes a minor
formatting nit as well.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NSteven French <sfrench@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/cifs/inode.c

@@ -219,15 +219,15 @@ int cifs_get_inode_info_unix(struct inode **pinode,
 	rc = CIFSSMBUnixQPathInfo(xid, pTcon, full_path, &find_data,
 				  cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
 					CIFS_MOUNT_MAP_SPECIAL_CHR);
-	if (rc) {
 	if (rc == -EREMOTE && !is_dfs_referral) {
 		is_dfs_referral = true;
 		cFYI(DBG2, ("DFS ref"));
 		/* for DFS, server does not give us real inode data */
 		fill_fake_finddataunix(&find_data, sb);
 		rc = 0;
-		}
-	}
+	} else if (rc)
+		goto cgiiu_exit;
+
 	num_of_bytes = le64_to_cpu(find_data.NumOfBytes);
 	end_of_file = le64_to_cpu(find_data.EndOfFile);