Created attachment 1470552 [details] smb.conf used (comments stripped, addresses changed) Description of problem: It seems that firewall helper module nf_conntrack_netbios_ns sometimes blocks samba packages which should be allowed. This causes (for example) that samba printers and shares are sometimes found and sometimes not. Version-Release number of selected component (if applicable): kernel-4.17.7-200.fc28.x86_64 firewalld-0.5.3-2.fc28.noarch samba-4.8.3-1.fc28.x86_64 How reproducible: Sometimes - not deterministic! Steps to Reproduce: 1. Install a server "sambaserver" which runs samba server and print server exporting print queues. Use a smb.conf file similar to the one attached. 2. Install a client "sambaclient" with samba client installed. 3. On sambaserver allow firewall service samba. 4. On sambaclient allow firewall service samba-client. 5. Run smbtree on sambaclient several times. Actual results: Often, smbtree prints nothing. Sometimes, smbtree prints a domain or workgroup name. Sometimes, smbtree prints a domain or workgroup name and the name of hosts in the domain or workgroup (indented and with "\\" prefix), and also the list of printers and shares of the host (more indented, and prefixed with "\\" hostname "\"). Expected results: smbtree should print all available domains and workgroups and each host with all available printers and shares on every call, not only sometimes. Additional info: I don't know what the right component is. I have chosen kernel because nf_conntrack_netbios_ns is a kernel module.
Created attachment 1470554 [details] tcpdump on sambaserver selecting packages from sambaclient while "smbtree" on sambaclient is called (addresses changed) I have stated tcpdump on both hosts while I called "smbtree" on sambaclient. Attached is the case when smbtree has printed nothing. In the attachment you can see that sambaclient rejects the answer of sambaserver with "ICMP host 192.0.2.2 unreachable - admin prohibited". I think this is the reason why smbtree has empty results and print nothing - it gets no information from sambaserver because sambaclient firewall / netfilter is blocking the answer from sambaserver. But I don't know why it does this. firewalld service samba-client is listed on active network interface zone. # iptables -L -v |grep netbios 1266 109K ACCEPT udp -- any any anywhere anywhere udp dpt:netbios-ns ctstate NEW 857 201K ACCEPT udp -- any any anywhere anywhere udp dpt:netbios-dgm ctstate NEW # lsmod |grep netbios nf_conntrack_netbios_ns 16384 1 nf_conntrack_broadcast 16384 1 nf_conntrack_netbios_ns nf_conntrack 147456 13 xt_conntrack,nf_nat_masquerade_ipv4,nf_conntrack_ipv6,nf_conntrack_ipv4,nf_nat,nf_conntrack_tftp,nf_nat_ipv6,ipt_MASQUERADE,nf_conntrack_netbios_ns,nf_nat_ipv4,nf_nat_tftp,nf_conntrack_broadcast,xt_CT But I also found this: # journalctl -b --no-hostname |grep conntrack Jul 23 06:53:52 dnsmasq[2129]: compile time options: IPv6 GNU-getopt DBus no-i18n IDN2 DHCP DHCPv6 no-Lua TFTP no-conntrack ipset auth DNSSEC loop-detect inotify Jul 25 11:56:20 kernel: nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead. Any ideas?
We apologize for the inconvenience. There is a large number of bugs to go through and several of them have gone stale. Due to this, we are doing a mass bug update across all of the Fedora 28 kernel bugs. Fedora 28 has now been rebased to 4.18.10-300.fc28. Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel. If you have moved on to Fedora 29, and are still experiencing this issue, please change the version to Fedora 29. If you experience different issues, please open a new bug report for those.
The problem still exists with kernel 4.18.14-200.fc28.x86_64 .
*********** MASS BUG UPDATE ************** We apologize for the inconvenience. There are a large number of bugs to go through and several of them have gone stale. Due to this, we are doing a mass bug update across all of the Fedora 28 kernel bugs. Fedora 28 has now been rebased to 4.20.5-100.fc28. Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel. If you have moved on to Fedora 29, and are still experiencing this issue, please change the version to Fedora 29. If you experience different issues, please open a new bug report for those.
*********** MASS BUG UPDATE ************** This bug is being closed with INSUFFICIENT_DATA as there has not been a response in 3 weeks. If you are still experiencing this issue, please reopen and attach the relevant data from the latest kernel you are running and any data that might have been requested previously.
Sorry for the delay. The problem still exists with kernel 4.20.10-200.fc29.x86_64 - same result as in comment #1.
(In reply to Edgar Hoch from comment #6) > Sorry for the delay. The problem still exists with kernel > 4.20.10-200.fc29.x86_64 - same result as in comment #1. But this is new: UNTRACKED: # iptables -L -v |grep netbios 64 4992 ACCEPT udp -- any any anywhere anywhere udp dpt:netbios-ns ctstate NEW,UNTRACKED 5 1105 ACCEPT udp -- any any anywhere anywhere udp dpt:netbios-dgm ctstate NEW,UNTRACKED
*********** MASS BUG UPDATE ************** We apologize for the inconvenience. There are a large number of bugs to go through and several of them have gone stale. Due to this, we are doing a mass bug update across all of the Fedora 29 kernel bugs. Fedora 29 has now been rebased to 5.2.9-100.fc29. Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel. If you have moved on to Fedora 30, and are still experiencing this issue, please change the version to Fedora 30. If you experience different issues, please open a new bug report for those.
The problem still exists with kernel 5.2.9-200.fc30.x86_64 - same result as in comment #1.
*********** MASS BUG UPDATE ************** We apologize for the inconvenience. There are a large number of bugs to go through and several of them have gone stale. Due to this, we are doing a mass bug update across all of the Fedora 30 kernel bugs. Fedora 30 has now been rebased to 5.5.7-100.fc30. Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel. If you have moved on to Fedora 31, and are still experiencing this issue, please change the version to Fedora 31. If you experience different issues, please open a new bug report for those.
The problem still exists with kernel kernel-5.5.8-200.fc31.x86_64 and samba-client-4.11.6-0.fc31.x86_64 .
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Fedora 31 changed to end-of-life (EOL) status on 2020-11-24. Fedora 31 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.