Bug 723391
| Summary: | tmux doesn't work without unconfined, but this may be a tmux behaviour issue | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Robin Powell <rlpowell> |
| Component: | selinux-policy | Assignee: | Miroslav Grepl <mgrepl> |
| Status: | CLOSED ERRATA | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | unspecified | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 15 | CC: | dominick.grift, dwalsh, mgrepl |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
| Whiteboard: | |||
| Fixed In Version: | selinux-policy-3.9.16-38.fc15 | Doc Type: | Bug Fix |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2011-09-07 00:18:45 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: | |||
First, thanks you try to use confined users and report bugs. The problem is we don't have a policy for tmux. So there is no transition for confined users. We could try to treat tmux with screen policy. Could you try to execute # chcon -t screen_exec_t /usr/bin/tmux # chcon -R -t screen_var_run_t /var/run/tmux Yep! That seems to do the trick. -Robin Hmm, no, not quite; that *mostly* works. The following is required to stop the AVC messages entirely:
#============= user_screen_t ==============
allow user_screen_t user_t:unix_stream_socket connectto;
#============= staff_screen_t ==============
allow staff_screen_t staff_t:dir search;
allow staff_screen_t staff_t:file { read open getattr };
The weird part is the staff_t dir and file stuff; when I run tmux as a staff_t user, those AVCs simply print out continuously, about once a second, like so (various lines with various allows allowed or not):
type=AVC msg=audit(1311474188.863:113454): avc: denied { search } for pid=31153 comm="tmux" name="31154" dev=proc ino=104906 scontext=staff_u:staff_r:staff_screen_t:s0 tcontext=staff_u:staff_r:staff_t:s0 tclass=dir
type=AVC msg=audit(1311474332.152:114587): avc: denied { read } for pid=31235 comm="tmux" name="cmdline" dev=proc ino=105414 scontext=staff_u:staff_r:staff_screen_t:s0 tcontext=staff_u:staff_r:staff_t:s0 tclass=file
type=AVC msg=audit(1311474586.902:117091): avc: denied { open } for pid=31711 comm="tmux" name="cmdline" dev=proc ino=106700 scontext=staff_u:staff_r:staff_screen_t:s0 tcontext=staff_u:staff_r:staff_t:s0 tclass=file
type=AVC msg=audit(1311474882.929:118192): avc: denied { getattr } for pid=31778 comm="tmux" path="/proc/31779/cmdline" dev=proc ino=106967 scontext=staff_u:staff_r:staff_screen_t:s0 tcontext=staff_u:staff_r:staff_t:s0 tclass=file
So apparently tmux looks at the /proc/ cmdline file about once a second? Dunno what's up with that (I'll let the tmux team know).
-Robin
Ah. That poking at the /proc/ cmdline is a useful/needed feature; it's so that windows can be named for the command running in them. -Robin Whoops, user_t needs it too:
#============= user_screen_t ==============
allow user_screen_t user_t:unix_stream_socket connectto;
allow user_screen_t user_t:dir search;
allow user_screen_t user_t:file { read open getattr };
#============= staff_screen_t ==============
allow staff_screen_t staff_t:dir search;
allow staff_screen_t staff_t:file { read open getattr };
-Robin
Looks like we need to add ps_process_pattern($1_screen_t, $3) TO screen_role_template. I just updated the policy in F16. Fixed in selinux-policy-3.9.16-36.fc15 selinux-policy-3.9.16-37.fc15 has been submitted as an update for Fedora 15. https://admin.fedoraproject.org/updates/selinux-policy-3.9.16-37.fc15 Do those chcon changes need to be propagated into the tmux package as well, or is this the entire fix? -Robin No the selinux-policy package will change the labels. Package selinux-policy-3.9.16-37.fc15: * should fix your issue, * was pushed to the Fedora 15 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing selinux-policy-3.9.16-37.fc15' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/selinux-policy-3.9.16-37.fc15 then log in and leave karma (feedback). Package selinux-policy-3.9.16-38.fc15: * should fix your issue, * was pushed to the Fedora 15 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing selinux-policy-3.9.16-38.fc15' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/selinux-policy-3.9.16-38.fc15 then log in and leave karma (feedback). selinux-policy-3.9.16-38.fc15 has been pushed to the Fedora 15 stable repository. If problems still persist, please make note of it in this bug report. |
Description of problem: tmux tries to create sockets in /var/run/tmux, like so: rlpowell@stodi> sudo find /var/run/tmux -ls 58858 0 drwxrwxr-x 5 root tmux 100 Jul 19 16:18 /var/run/tmux 239364 0 drwx------ 2 djanatyn tmux 60 Jul 19 16:18 /var/run/tmux/tmux-1052 239373 0 srw-rw---- 1 djanatyn djanatyn 0 Jul 19 16:18 /var/run/tmux/tmux-1052/default 238111 0 drwx------ 2 bairyn tmux 60 Jul 19 17:24 /var/run/tmux/tmux-1055 242839 0 srw-rw---- 1 bairyn bairyn 0 Jul 19 17:24 /var/run/tmux/tmux-1055/default 237246 0 drwx------ 2 rlpowell tmux 60 Jul 19 15:54 /var/run/tmux/tmux-1000 237338 0 srw-rw---- 1 rlpowell rlpowell 0 Jul 19 15:54 /var/run/tmux/tmux-1000/default This fails. The following bit of selinux policy fix it for staff_u and user_u ; whether you think that's a good plan is your call. tmux -S can be used to fix this, but AFAIK there's no tmux conf variable to change the socket dir, so it's a real issue in that out-of-the-box tmux doesn't work, so I think either the selinux policy or the default tmux socket dir should be changed in mainline Fedora. module mytmux 1.0; require { type staff_t; type user_t; type var_run_t; class sock_file { write create unlink }; class dir { write create add_name remove_name }; } #============= staff_t ============== allow staff_t var_run_t:dir { write remove_name create add_name }; allow staff_t var_run_t:sock_file { write create unlink }; #============= user_t ============== allow user_t var_run_t:dir { write create add_name remove_name }; allow user_t var_run_t:sock_file { create write unlink };