Bug 1250550

Summary: Allow snapperd one-way communication with clients via pipe
Product: Red Hat Enterprise Linux 7 Reporter: Ondrej Kozina <okozina>
Component: selinux-policyAssignee: Lukas Vrabec <lvrabec>
Status: CLOSED ERRATA QA Contact: Milos Malik <mmalik>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 7.2CC: lvrabec, mgrepl, mmalik, okozina, plautrba, pvrabec, ssekidde
Target Milestone: rc   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: selinux-policy-3.13.1-39.el7 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2015-11-19 10:43:06 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Ondrej Kozina 2015-08-05 12:47:29 UTC
Could you please allow snapperd to pass data (one way only) via pipe negotiated over dbus?

type=AVC msg=audit(1438778241.065:237): avc:  denied  { read } for  pid=1550 comm="dbus-daemon" path="pipe:[63866]" dev="pipefs" ino=63866 scontext=system_u:system_r:system_dbusd_t:s0-s0:c0.c1023 tcontext=system_u:system_r:snapperd_t:s0-s0:c0.c1023 tclass=fifo_file

We do not open new hole since snapper is already effectively bypassing MAC by passing list of files over dbus already. Now we just send the list via pipe because of dbus message size limitations


Version-Release number of selected component (if applicable):
snapper-0.1.7-10.el7
selinux-policy-3.13.1-36.el7.noarch

How reproducible:
Always

Steps to Reproduce:
1. create two snapshot with snapper (so that diff is non-empty)
2. run snapper -c some_name status 1..2 (1 and 2 are snapshots created in step 1.)


Actual results:
[root@ibm-p8-02-lp3 xfs]# snapper -c xfs status 1..2
Failure (org.freedesktop.DBus.Error.NoReply).

Comment 2 Milos Malik 2015-08-05 13:04:06 UTC
Does the scenario trigger any other AVCs in permissive mode?

Comment 3 Ondrej Kozina 2015-08-06 08:14:22 UTC
This is full listing. AFAICT only the read denial is blocking snapperd from sending data back to clients.

type=AVC msg=audit(1438848621.979:313): avc:  denied  { noatsecure } for  pid=30847 comm="snapperd" scontext=system_u:system_r:system_dbusd_t:s0-s0:c0.c1023 tcontext=system_u:system_r:snapperd_t:s0-s0:c0.c1023 tclass=process

type=AVC msg=audit(1438848621.979:313): avc:  denied  { siginh } for  pid=30847 comm="snapperd" scontext=system_u:system_r:system_dbusd_t:s0-s0:c0.c1023 tcontext=system_u:system_r:snapperd_t:s0-s0:c0.c1023 tclass=process

type=AVC msg=audit(1438848621.979:313): avc:  denied  { rlimitinh } for  pid=30847 comm="snapperd" scontext=system_u:system_r:system_dbusd_t:s0-s0:c0.c1023 tcontext=system_u:system_r:snapperd_t:s0-s0:c0.c1023 tclass=process

type=AVC msg=audit(1438848622.149:314): avc:  denied  { read } for  pid=1393 comm="dbus-daemon" path="pipe:[58763]" dev="pipefs" ino=58763 scontext=system_u:system_r:system_dbusd_t:s0-s0:c0.c1023 tcontext=system_u:system_r:snapperd_t:s0-s0:c0.c1023 tclass=fifo_file

Comment 6 Miroslav Grepl 2015-08-06 14:34:19 UTC
We want to allow

type=AVC msg=audit(1438848622.149:314): avc:  denied  { read } for  pid=1393 comm="dbus-daemon" path="pipe:[58763]" dev="pipefs" ino=58763 scontext=system_u:system_r:system_dbusd_t:s0-s0:c0.c1023 tcontext=system_u:system_r:snapperd_t:s0-s0:c0.c1023 tclass=fifo_file

Comment 10 errata-xmlrpc 2015-11-19 10:43:06 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://rhn.redhat.com/errata/RHBA-2015-2300.html