lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Fri, 13 Mar 2009 14:25:07 -0700 (PDT) From: David Miller <davem@...emloft.net> To: ilpo.jarvinen@...sinki.fi Cc: dada1@...mosbay.com, netdev@...r.kernel.org Subject: Re: [RFC] tcp: allow timestamps even if SYN packet has tsval=0 From: "Ilpo Järvinen" <ilpo.jarvinen@...sinki.fi> Date: Thu, 12 Mar 2009 09:26:20 +0200 (EET) > On Wed, 11 Mar 2009, David Miller wrote: > > > From: Eric Dumazet <dada1@...mosbay.com> > > Date: Wed, 11 Mar 2009 13:17:54 +0100 > > > > > So apparently WindowsXP sends a NULL tsval in SYN packet, then > > > subsequent packets get a real value (60498) in this case. > > > > > > This seems to work on other OS as well, so is the following patch > > > considered evil ? Do we have security concerns or only risking > > > windows client to have slightly wrong rtt estimation at the begining > > > of the tcp session ? > > > > I think we'll have to accept this. > > > > I don't see other systems blocking initial ts_ecn values of > > zero like we do. > > What about the fact that PAWS could bite us leaving us a hung connection > if timestamp changes too much when we get the first ACK? Though I doubt > you can get windows to run long enough for this to become a problem if > they always start from zero... ;-) I really don't think it's a real issue, and Windows XP should be happy we're willing to try timestamps at all with it :-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists