Bug 560807

Summary: SELinux is preventing /usr/bin/tpb "read" access on nvram.
Product: [Fedora] Fedora Reporter: G. E. McLean <radeead>
Component: selinux-policyAssignee: Daniel Walsh <dwalsh>
Status: CLOSED WONTFIX QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: low    
Version: 12CC: dwalsh, mgrepl, Robert-Martin
Target Milestone: ---   
Target Release: ---   
Hardware: i386   
OS: Linux   
Whiteboard: setroubleshoot_trace_hash:2302e3e7fb8800b4cf3f1f18352132fda597da45bb6c42f0b06051b5cd95eb2b
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2010-02-02 13:23:43 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:

Description G. E. McLean 2010-02-01 21:59:16 UTC
Summary:

SELinux is preventing /usr/bin/tpb "read" access on nvram.

Detailed Description:

SELinux denied access requested by tpb. It is not expected that this access is
required by tpb and this access may signal an intrusion attempt. It is also
possible that the specific version or configuration of the application is
causing it to require additional access.

Allowing Access:

You can generate a local policy module to allow this access - see FAQ
(http://docs.fedoraproject.org/selinux-faq-fc5/#id2961385) Please file a bug
report.

Additional Information:

Source Context                xguest_u:xguest_r:xguest_t:s0
Target Context                system_u:object_r:nvram_device_t:s0
Target Objects                nvram [ chr_file ]
Source                        tpb
Source Path                   /usr/bin/tpb
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           tpb-0.6.4-12.fc12
Target RPM Packages           
Policy RPM                    selinux-policy-3.6.32-73.fc12
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Plugin Name                   catchall
Host Name                     (removed)
Platform                      Linux (removed)
                              2.6.31.12-174.2.3.fc12.i686 #1 SMP Mon Jan 18
                              20:22:46 UTC 2010 i686 i686
Alert Count                   2
First Seen                    Mon 01 Feb 2010 01:56:13 PM PST
Last Seen                     Mon 01 Feb 2010 01:56:14 PM PST
Local ID                      a678c91c-a632-48d6-99f3-b51b27b7796e
Line Numbers                  

Raw Audit Messages            

node=(removed) type=AVC msg=audit(1265061374.317:28674): avc:  denied  { read } for  pid=4542 comm="tpb" name="nvram" dev=tmpfs ino=3040 scontext=xguest_u:xguest_r:xguest_t:s0 tcontext=system_u:object_r:nvram_device_t:s0 tclass=chr_file

node=(removed) type=SYSCALL msg=audit(1265061374.317:28674): arch=40000003 syscall=5 success=no exit=-13 a0=83b3858 a1=800 a2=7 a3=83b3a98 items=0 ppid=1 pid=4542 auid=501 uid=501 gid=501 euid=501 suid=501 fsuid=501 egid=501 sgid=501 fsgid=501 tty=(none) ses=11 comm="tpb" exe="/usr/bin/tpb" subj=xguest_u:xguest_r:xguest_t:s0 key=(null)



Hash String generated from  selinux-policy-3.6.32-73.fc12,catchall,tpb,xguest_t,nvram_device_t,chr_file,read
audit2allow suggests:

#============= xguest_t ==============
allow xguest_t nvram_device_t:chr_file read;

Comment 1 Daniel Walsh 2010-02-02 13:21:52 UTC
Only unconfined domains currently can read this device.  Why does xguest need to read it?

Comment 2 Daniel Walsh 2010-02-02 13:23:43 UTC
nvram Special File
Purpose

Provides access to platform-specific nonvolatile RAM used for system boot, configuration, and fatal error information. This access is achieved through the machine I/O device driver.
Description

The /dev/nvram character special file provides access to the machine device driver for accessing or modifying machine-specific nonvolatile RAM. The appropriate privilege is required to open the nvram special file. The nvram special file is used by machine-specific configuration programs to store or retrieve configuration and boot information using the nonvolatile RAM or ROM provided on the machine. The nvram special file supports open, close, read, and ioctl operations.
Note:
Application programs should not access the nonvolatile RAM. Since nonvolatile RAM is platform-specific, any reliance on its presence and implementation places portability constraints upon the using application. In addition, accessing the nonvolatile RAM may cause loss of system startup and configuration information. Such a loss could require system administrative or maintenance task work to rebuild or recover.

This does not sound like something a confined user should be looking at.

Comment 3 Miroslav Grepl 2010-06-21 12:37:57 UTC
*** Bug 606039 has been marked as a duplicate of this bug. ***