bugzilla-daemon at mindrot.org
2006-Oct-12 23:53 UTC
[Bug 1250] sshd client connections persist across IP change
http://bugzilla.mindrot.org/show_bug.cgi?id=1250 Summary: sshd client connections persist across IP change Product: Portable OpenSSH Version: 4.3p2 Platform: ix86 OS/Version: Linux Status: NEW Severity: trivial Priority: P4 Component: sshd AssignedTo: bitbucket at mindrot.org ReportedBy: openssh.mindrot.org at neo-neural.net On a default build using Debian 3.1r3, OpenSSH 4.3p2, on a system with multiple NICs installed: 1. connect to sshd server via IP with eth0 up (all other interfaces down) 2. bring down eth0 from console, bring up eth1 on a different IP in same subnet 3. observe initial sshd connection as still active and working The client was PuTTY 0.58, for posterity. No DNS or hosts entries existed for the server. sshd_config is default, listening on all available IPs. This is more of a feature than a bug, I suppose, but while I can't yet imagine how someone could exploit this improperly, it certainly wasn't expected behaviour (which was for the client connection to die eventually). ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.
bugzilla-daemon at mindrot.org
2006-Oct-13 00:34 UTC
[Bug 1250] sshd client connections persist across IP change
http://bugzilla.mindrot.org/show_bug.cgi?id=1250 ------- Comment #1 from dtucker at zip.com.au 2006-10-13 10:34 ------- If you run "netstat -n" do you see the TCP connections with the old or new local IP address? I suspect that the IP address is still configured on eth0 and the kernel is still processing the connections (as long as the client routes the packets to the server) and that if you unconfigure the IP ("ifconfig eth0 inet 0.0.0.0") it will stop working. Either way, having a TCP connection behave this way is a bug/feature of the OS... ------- You are receiving this mail because: ------- You are the assignee for the bug, or are watching the assignee.