Integer overflow

Multiple integer overflows in Dibbler 0.6.0 allow remote attackers to cause a denial of service (daemon crash) via packets containing options with large lengths, which trigger attempts at excessive memory allocation, as demonstrated by (1) the TSrvMsg constructor in SrvMessages/SrvMsg.cpp; the (2) TClntMsg, (3) TClntOptIAAddress, (4) TClntOptIAPrefix, (5) TOptVendorSpecInfo, and (6) TOptOptionRequest constructors; and the (7) TRelIfaceMgr::decodeRelayRepl, (8) TRelMsg::decodeOpts, and (9) TSrvIfaceMgr::decodeRelayForw methods.