nfsd4: fix xdr4 inclusion of escaped char

commit 5a64e569 upstream.

Fix a bug where nfsd4_encode_components_esc() includes the esc_end char as
an additional string encoding.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: e7a0444a "nfsd: add IPv6 addr escaping to fs_location hosts"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

fs/nfsd/nfs4xdr.c

@@ -1777,6 +1777,9 @@ static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
 		}
 		else
 			end++;
+		if (found_esc)
+			end = next;
+
 		str = end;
 	}
 	pathlen = htonl(xdr->buf->len - pathlen_offset);