Description of problem: rpcbind uses a random UDP port between about 600/UDP and 1023/UDP. Sometimes rpcbind happens to use a UDP port that is required for Kerberos. In that case, Kerberos fails to start. FreeIPA's CI is running into the issue every now and then. Version-Release number of selected component (if applicable): rpcbind-0.2.4-8.rc3.fc27.x86_64 How reproducible: rarely Steps to Reproduce: 1. restart rpcbind a lot until it eventually uses 749/udp Actual results: kadmin fails to start Jun 19 13:12:13 master.ipa.test kadmind[16427](info): setting up network... kadmind: setsockopt(8,IPV6_V6ONLY,1) worked kadmind: setsockopt(10,IPV6_V6ONLY,1) worked kadmind: Address already in use - Cannot bind server socket on 0.0.0.0.749 Jun 19 13:12:13 master.ipa.test kadmind[16427](Error): Failed setting up a RPC socket (for 0.0.0.0.749) kadmind: Address already in use - Error setting up network Jun 19 13:13:13 master.ipa.test kadmind[17767](info): setting up network... kadmind: setsockopt(8,IPV6_V6ONLY,1) worked kadmind: setsockopt(10,IPV6_V6ONLY,1) worked kadmind: Address already in use - Cannot bind server socket on 0.0.0.0.749 Jun 19 13:13:13 master.ipa.test kadmind[17767](Error): Failed setting up a RPC socket (for 0.0.0.0.749) kadmind: Address already in use - Error setting up network Expected results: rpcbind never takes a Kerberos port Additional info: rpcbind should be more careful when it selects a random UDP port. I suggest that rpcbind never uses a UDP port that has been reserved for a service in /etc/services, e.g. with getservbyport(port, "udp"). See https://linux.die.net/man/3/getservbyport The issue affects F27, F28, rawhide, and RHEL 7. RHEL 6 had portreserve but it's no longer available in RHEL 7.
Put to modified by mistake *sigh .
commit 0bc1c0ae7ce61a7ac8a8e9a9b2086268f011abf0 (HEAD -> covscan, origin/master, origin/HEAD, master) Author: Steve Dickson <steved> Date: Tue Oct 9 09:19:50 2018 -0400 rpcinfo: Fix stack buffer overflow
(In reply to Steve Dickson from comment #4) > commit 0bc1c0ae7ce61a7ac8a8e9a9b2086268f011abf0 (HEAD -> covscan, > origin/master, origin/HEAD, master) > Author: Steve Dickson <steved> > Date: Tue Oct 9 09:19:50 2018 -0400 > > rpcinfo: Fix stack buffer overflow This is the wrong patch.... but the problem is fixed in the latest release.