Description of problem: Earlier versions closes connections (old inetd does this, too) by server on tcp/daytime Version-Release number of selected component (if applicable): Tested: xinetd-2.3.9 on RHL 7.2, 6.2 and 7.3 How reproducible: Always Steps to Reproduce: 1. Update to xinetd-2.3.9 2. Enable tcp/daytime 3. telnet localhost daytime Actual Results: # telnet localhost 13 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. 17 OCT 2002 10:13:08 CEST (nothing happen here) Expected Results: # telnet localhost 13 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. 17 OCT 2002 10:18:21 CEST Connection closed by foreign host. Additional info: This was tested on RHL 7.2, 7.3 and 6.2 (rebuilded 2.3.9) old 2.3.3 was ok and shows same as old inetd (on RHL 6.2) Why was this behavior changed? BTW: could lead to many open sockets, perhaps a candidate for a DoS?
This does lead to DoS. I have ~15 computers hitting daytime every 5 minutes. After about a 12 hours, connections are no longer accepted and my message log starts seeing "too many open files" Oct 18 08:58:35 fmymca xinetd[31399]: service imap, accept: Too many open files (errno = 24) Oct 18 08:58:35 fmymca xinetd[31399]: service time-stream, accept: Too many open files (errno = 24) Oct 18 08:58:41 fmymca xinetd[31399]: service imap, accept: Too many open files (errno = 24) Oct 18 08:58:41 fmymca xinetd[31399]: service time-stream, accept: Too many open files (errno = 24) Oct 18 08:59:29 fmymca xinetd[31399]: service time-stream, accept: Too many open files (errno = 24) Oct 18 08:59:47 fmymca xinetd[31399]: service time-stream, accept: Too many open files (errno = 24) Oct 18 08:59:57 fmymca xinetd[31399]: service imap, accept: Too many open files (errno = 24) Oct 18 08:59:57 fmymca xinetd[31399]: service time-stream, accept: Too many open files (errno = 24) Oct 18 09:00:01 fmymca xinetd[31399]: service time-stream, accept: Too many open files (errno = 24) Oct 18 09:00:01 fmymca xinetd[31399]: service time-stream, accept: Too many open files (errno = 24) Oct 18 09:00:01 fmymca xinetd[31399]: service time-stream, accept: Too many open files (errno = 24) Oct 18 09:00:04 fmymca xinetd[31399]: service telnet, accept: Too many open files (errno = 24)
I've increased priority because of the reported DoS, looks like this bug should be fixed really quickly by RHL and/or the xinetd developers.
There is more info on this bug in #76146. So marked it as duplicate. *** This bug has been marked as a duplicate of 76146 ***