Messages in this thread | | | Date | Thu, 28 Feb 2008 21:41:47 +0100 | From | Willy Tarreau <> | Subject | Re: SO_REUSEADDR not allowing server and client to use same port |
| |
On Thu, Feb 28, 2008 at 08:19:26PM +0000, Alan Cox wrote: > > Currently, Linux does not allow reuse of same local port for both TCP server and > > TCP client. I understand that there may be a need to prevent two servers from > > Think about what happens for simultaneous connect (that obscure little > corner of the tcp/ip spec). Now think about what it means for security. > > ALan
exactly. That's why I think that requiring the server to explicitly allow socket reuse is mandatory. On another side of the problem, I really think that we should make the simultaneous connect configurable. I've been patching all of my own 2.4 kernels for a while to add a config option to turn it off because there is a real security issue with this on. At least for mainline, it should be a sysctl. No stateful firewall I know supports the feature, so legitimate uses of this feature are likely very very small.
Willy
| |