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Description of problem: Similar to the report in bug #1103439 for RHEL 6, named on both Fedora 20 and 21 triggers AVC denials when trying to bind to specific source ports, particularly these: 1935 2605 4321 4444 5546 8554 8610 8611 8612 8613 8614 These (silent) denials manifest themselves as log entries like this: Mar 04 23:32:54 xxx named[24257]: dispatch 0x7fe27c091790: open_socket(0.0.0.0#2605) -> permission denied: continuing ...for which the associated AVC looked like this: type=AVC msg=audit(1425529974.811:8056): avc: denied { name_bind } for pid=24261 comm="named" src=2605 scontext=system_u:system_r:named_t:s0 tcontext=system_u:object_r:bgp_port_t:s0 tclass=udp_socket permissive=0 type=SYSCALL msg=audit(1425529974.811:8056): arch=c000003e syscall=49 success=no exit=-13 a0=20d a1=7fe284398460 a2=10 a3=7fe284398248 items=0 ppid=1 pid=24261 auid=4294967295 uid=53 gid=53 euid=53 suid=53 fsuid=53 egid=53 sgid=53 fsgid=53 tty=(none) ses=4294967295 comm="named" exe="/usr/sbin/named" subj=system_u:system_r:named_t:s0 key=(null) Several comments in the other bug suggest that this is or was fixed in Fedora or upstream, but this does not appear to be the case. I'm opening this bug specifically to cover the issue present in Fedora. Version-Release number of selected component (if applicable): selinux-policy-3.13.1-105.3.fc21.noarch selinux-policy-targeted-3.13.1-105.3.fc21.noarch Expected results: named should be able to bind to any available source port >1024 without restriction. A comment on the other bug implied this was the intended behavior in Fedora, which suggests there may be a policy conflict.
#============= named_t ============== #!!!! This avc has a dontaudit rule in the current policy allow named_t bgp_port_t:udp_socket name_bin Did you turn dontaudit rules off? The point is we allow "bind" to all unreserved ports.
Okay, since the other bug was closed for the same stated reason and later reopened after the issue was reproduced: The policy does not do what you think. I turned off dontaudit rules temporarily to demonstrate that these: Mar 16 12:02:27 xxx named[867]: dispatch 0x7fbaf48b3760: open_socket(0.0.0.0#4444) -> permission denied: continuing Mar 16 12:02:35 xxx named[867]: dispatch 0x7fbaf48b8700: open_socket(0.0.0.0#4444) -> permission denied: continuing Mar 16 12:13:25 xxx named[867]: dispatch 0x7fbad4019810: open_socket(0.0.0.0#4444) -> permission denied: continuing Mar 16 16:58:55 xxx named[867]: dispatch 0x7fbad4016d30: open_socket(0.0.0.0#8613) -> permission denied: continuing Mar 16 23:35:48 xxx named[867]: dispatch 0x7fbad4017350: open_socket(0.0.0.0#8613) -> permission denied: continuing Mar 17 19:12:49 xxx named[867]: dispatch 0x7fbaf48b7ac0: open_socket(::#4321) -> permission denied: continuing Mar 17 21:08:14 xxx named[867]: dispatch 0x7fbaf48b3760: open_socket(0.0.0.0#4444) -> permission denied: continuing Mar 17 22:58:51 xxx named[867]: dispatch 0x7fbaf48b74a0: open_socket(0.0.0.0#8613) -> permission denied: continuing Mar 18 00:49:01 xxx named[867]: dispatch 0x7fbaf48b49c0: open_socket(0.0.0.0#4321) -> permission denied: continuing ...are in fact caused by SELinux. All of those occurred with dontaudit rules enabled, as did the ~100 others between these and the earlier entry in this bug. The system that produced these isn't very busy, but I have others where the problem is far worse -- thousands of denials per day. It's also not limited to the single rule you listed above. Rather, as stated in bug #1103439 by several people, it's all of these ports: ╶➤ journalctl -lu named |perl -lne 'next unless /open_socket/; /#(\d+)\)/; $x{$1}++; END { print join(" ", sort keys %x) }' 1935 2605 4321 4444 5546 8554 8610 8611 8612 8613 8614 named is not allowed to bind to these ports by the current policy. Multiple Red Hat employees have now stated that it should be allowed, yet this issue is present in every current supported Fedora, RHEL, and CentOS release, and has been reproduced by at least one other Red Hat employee. The point is, this is is a bug. Full stop.
That was the idea. To not allow bind these reserved port type and force to bind unreserved port type. But yes this is not correct way how to handle it and we should allow bind any UDP port > 1024.
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Fedora 21 changed to end-of-life (EOL) status on 2015-12-01. Fedora 21 is no longer maintained, which means that it will not receive any further security or bug fix updates. As a result we are closing this bug. If you can reproduce this bug against a currently maintained version of Fedora please feel free to reopen this bug against that version. If you are unable to reopen this bug, please file a new report against the current release. If you experience problems, please add a comment to this bug. Thank you for reporting this bug and we are sorry it could not be fixed.
So, this bug was closed automatically by the system as EOL for the relevant Fedroa version. However, there is no resolution to this, nor a follow-up to another place where this is tracked. I can observe these denials on a RHEL7.3 Beta system as of this date.
One possible candidate for the status tracking is https://bugzilla.redhat.com/show_bug.cgi?id=1312972