Bug 441991
| Summary: | SELinux prevented slapd from reading files stored on a NFS filesytem. | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Kahlil Hodgson <kahlil.hodgson> |
| Component: | openldap | Assignee: | Jan Safranek <jsafrane> |
| Status: | CLOSED INSUFFICIENT_DATA | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | low | Docs Contact: | |
| Priority: | low | ||
| Version: | 8 | ||
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2008-11-26 11:09:15 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
Oh, and I only get it when restarting nscd. This looks like a leaked file descriptor to .ldaprc. I have no idea how it is happening. It can probably be safely ignored. Don't know if this helps, but I have recently added 'root_squash' to my NFS export definitions, and now I no longer get the alert on restart of 'nscd'. I am not sure I understand the bug correctly. Please correct me if I am wrong: - you have users in ldap and configured /etc/ldap.conf and /etc/nsswitch.conf - you have root's home on nfs volume - the nfs volume has no_root_squash - and if you run "service nscd restart", you get the AVC above If the above is correct, I do not understand why nscd calls /usr/sbin/setsebool - it doesn't do that on my machine and I do not see any reason to do so. Please provide strace of the nscd, i.e. run "service nscd stop; strace -o nscd-trace.log nscd -d" Not quite :-) - Unprivileged users are in ldap (as above) running over TLS - I'm using pam_ldap for authentication - /home is an NFS mount point, /root is local - selinux has use_nfs_home_dirs set to on - sealertd was giving me the above warnings (nscd does not call setbool, I was simply proving that use_nfs_home_dirs was set ;-) ) - I noticed the alert when I restarted nscd ... _ahhh_... I was using sudo! So when I do 'sudo service nscd restart' from my home directory I was getting the alert consistently. (Sorry, I forgot to mention the sudo bit). Now that I have set 'root_squash' for the NFS export, the error has gone, presumably because root can't see into my home dir anymore, and won't attempt to access '~/.ldaprc', and hence won't trigger the SE alert. My guess is nscd is not checking its $EUID when its looking for conf files. Hmmm, lots of things have changed since I reported this bug. If I get a chance I'll mount home on a safe box with 'no_root_squash' set and see if I can reproduce again. Well, that sounds better, but the AVC above is produced by /usr/sbin/setsebool, not nscd. I am still not able to reproduce it. Today I reviewed the code and I see that ldap client library opens the .ldaprc only to read it and then it is immediately closed. Please provide strace of the application (ncsd? sudo? setsebool?), which causes the AVC. Sorry, been off the internet for a week. I'll should be able to get you a trace this weekend :-) I turned 'no_root_squash' back on for one of my servers, but no sign of the AVC, so that was just a coincidence. A lot of things have changed since I reported the bug -- both selinux and kernel have been upgraded -- and sadly I did not make a copy of the OS at the time -- I think I'll do that in future. I gather we have just hit some really weird edge case. Alhough I would be nice to understand what was going wrong, I'm happy to let this bug slide for the moment (it never stopped anything from working) as I don't have a lot of spare time left to track the issue. Cheers! Kal ok, I'm setting needinfo to clearly state where is the ball This message is a reminder that Fedora 8 is nearing its end of life. Approximately 30 (thirty) days from now Fedora will stop maintaining and issuing updates for Fedora 8. It is Fedora's policy to close all bug reports from releases that are no longer maintained. At that time this bug will be closed as WONTFIX if it remains open with a Fedora 'version' of '8'. Package Maintainer: If you wish for this bug to remain open because you plan to fix it in a currently maintained version, simply change the 'version' to a later Fedora version prior to Fedora 8's end of life. Bug Reporter: Thank you for reporting this issue and we are sorry that we may not be able to fix it before Fedora 8 is end of life. If you would still like to see this bug fixed and are able to reproduce it against a later version of Fedora please change the 'version' of this bug to the applicable version. If you are unable to change the version, please add a comment here and someone will do it for you. Although we aim to fix as many bugs as possible during every release's lifetime, sometimes those efforts are overtaken by events. Often a more recent Fedora release includes newer upstream software that fixes bugs or makes them obsolete. The process we are following is described here: http://fedoraproject.org/wiki/BugZappers/HouseKeeping reporter did not provide enough information to track this bug and workaround is available. |
Despite having: <kal@buffy:~> getsebool use_nfs_home_dirs use_nfs_home_dirs --> on <kal@buffy:~> I'm getting: Source Context unconfined_u:system_r:setsebool_t:s0-s0:c0.c1023 Target Context system_u:object_r:nfs_t:s0 Target Objects ./.ldaprc [ file ] Source setsebool Source Path /usr/sbin/setsebool Port <Unknown> Host buffy.finexium.com Source RPM Packages policycoreutils-2.0.33-3.fc8 Target RPM Packages Policy RPM selinux-policy-3.0.8-98.fc8 Selinux Enabled True Policy Type targeted MLS Enabled True Enforcing Mode Enforcing Plugin Name use_nfs_home_dirs Host Name buffy.finexium.com Platform Linux buffy.finexium.com 2.6.24.4-64.fc8 #1 SMP Sat Mar 29 09:15:49 EDT 2008 x86_64 x86_64 Alert Count 2 First Seen Wed Mar 26 12:20:43 2008 Last Seen Fri Apr 11 13:41:45 2008 Local ID 4182386b-03a4-4bea-9e30-8e8a4b88e1ab Line Numbers Raw Audit Messages host=buffy.finexium.com type=AVC msg=audit(1207885305.669:2154): avc: denied { read } for pid=25892 comm="setsebool" name=".ldaprc" dev=0:17 ino=1279136 scontext=unconfined_u:system_r:setsebool_t:s0-s0:c0.c1023 tcontext=system_u:object_r:nfs_t:s0 tclass=file host=buffy.finexium.com type=SYSCALL msg=audit(1207885305.669:2154): arch=c000003e syscall=2 success=no exit=-13 a0=2aaaae264460 a1=0 a2=1b6 a3=0 items=0 ppid=25184 pid=25892 auid=500 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts2 comm="setsebool" exe="/usr/sbin/setsebool" subj=unconfined_u:system_r:setsebool_t:s0-s0:c0.c1023 key=(null) However it does not appear to be impacting anything important (yet).