netdev - Re: [PATCH v2] sctp: Implement quick failover draft from tsvwg

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20120719104513.GB2070@hmsreliant.think-freely.org>
Date:	Thu, 19 Jul 2012 06:45:13 -0400
From:	Neil Horman <nhorman@...driver.com>
To:	Joe Perches <joe@...ches.com>
Cc:	netdev@...r.kernel.org, Vlad Yasevich <vyasevich@...il.com>,
	Sridhar Samudrala <sri@...ibm.com>,
	"David S. Miller" <davem@...emloft.net>, linux-sctp@...r.kernel.org
Subject: Re: [PATCH v2] sctp: Implement quick failover draft from tsvwg

On Wed, Jul 18, 2012 at 01:30:58PM -0700, Joe Perches wrote:
> On Wed, 2012-07-18 at 14:01 -0400, Neil Horman wrote:
> > I've seen several attempts recently made to do quick failover of sctp transports
> > by reducing various retransmit timers and counters.  While its possible to
> > implement a faster failover on multihomed sctp associations, its not
> > particularly robust, in that it can lead to unneeded retransmits, as well as
> > false connection failures due to intermittent latency on a network.
> 
> trivia:
> 
> > diff --git a/net/sctp/associola.c b/net/sctp/associola.c
> 
> > @@ -871,6 +885,10 @@ void sctp_assoc_control_transport(struct sctp_association *asoc,
> >  		spc_state = SCTP_ADDR_UNREACHABLE;
> >  		break;
> >  
> > +	case SCTP_TRANSPORT_PF:
> > +		transport->state = SCTP_PF;
> > +		ulp_notify = false;
> > +		break;
> 
> nicer to add a newline here
> 
Ack, I'll fix that.

> >  	default:
> >  		return;
> >  	}
> > @@ -878,12 +896,15 @@ void sctp_assoc_control_transport(struct sctp_association *asoc,
> []
> > +	if (ulp_notify) {
> > +		memset(&addr, 0, sizeof(struct sockaddr_storage));
> > +		memcpy(&addr, &transport->ipaddr,
> > +		       transport->af_specific->sockaddr_len);
> 
> Perhaps it's better to do the memcpy then the memset of the
> space left instead.
> 
> 		memcpy(&addr, &transport->ipaddr, transport->af_specific->sockaddr_len);
> 		memset((char *)&addr) + transport->af_specific->sockaddr_len, 0,
> 		       sizeof(struct sockaddr_storage) - transport->af_specific->sockaddr_len);
> 		       
> 
hmm, not sure about that. It works either way for me, but I've not changed that
code, just the condition under which it was executed.  I'd rather save cleanups
like that for a separate patch if you don't mind.
Neil

> 
> 
--
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