Bug 730026

Summary: SELinux is preventing /usr/sbin/vbetool from 'mmap_zero' accesses on the memprotect Unknown.
Product: [Fedora] Fedora Reporter: Lari Tanase <larieu>
Component: selinux-policyAssignee: Miroslav Grepl <mgrepl>
Status: CLOSED CANTFIX QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: unspecified    
Version: rawhideCC: dominick.grift, dwalsh, mgrepl
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard: setroubleshoot_trace_hash:71b6811cb0f974ca3815b68b8b0ee7d47077c1d90bc6675de04159a77e861932
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-08-11 15:21:29 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:

Description Lari Tanase 2011-08-11 15:17:53 UTC
SELinux is preventing /usr/sbin/vbetool from 'mmap_zero' accesses on the memprotect Unknown.

*****  Plugin mmap_zero (34.9 confidence) suggests  **************************

If you do not think /usr/sbin/vbetool should need to mmap low memory in the kernel.
Then you may be under attack by a hacker, this is a very dangerous access.
Do
contact your security administrator and report this issue.

*****  Plugin vbetool (34.9 confidence) suggests  ****************************

If you want to ignore this AVC because it is dangerous and your machine seems to be working correctly.
Then you must tell SELinux about this by enabling the vbetool_mmap_zero_ignore boolean.
Do
# setsebool -P vbetool_mmap_zero_ignore 1

*****  Plugin catchall_boolean (28.0 confidence) suggests  *******************

If you want to control the ability to mmap a low area of the address space, as configured by /proc/sys/kernel/mmap_min_addr.
Then you must tell SELinux about this by enabling the 'mmap_low_allowed' boolean.
Do
setsebool -P mmap_low_allowed 1

*****  Plugin catchall (3.94 confidence) suggests  ***************************

If you believe that vbetool should be allowed mmap_zero access on the Unknown memprotect by default.
Then you should report this as a bug.
You can generate a local policy module to allow this access.
Do
allow this access for now by executing:
# grep vbetool /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp

Additional Information:
Source Context                unconfined_u:unconfined_r:vbetool_t:s0-s0:c0.c1023
Target Context                unconfined_u:unconfined_r:vbetool_t:s0-s0:c0.c1023
Target Objects                Unknown [ memprotect ]
Source                        vbetool
Source Path                   /usr/sbin/vbetool
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           vbetool-1.2.2-1.fc12
Target RPM Packages           
Policy RPM                    selinux-policy-3.9.16-35.fc15
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     (removed)
Platform                      Linux (removed) 2.6.40-4.fc15.x86_64 #1 SMP
                              Fri Jul 29 18:46:53 UTC 2011 x86_64 x86_64
Alert Count                   2
First Seen                    Thu 11 Aug 2011 05:15:34 PM CEST
Last Seen                     Thu 11 Aug 2011 05:16:02 PM CEST
Local ID                      2b7fba07-d27e-495a-bf4b-b7584e3dae70

Raw Audit Messages
type=AVC msg=audit(1313075762.379:100): avc:  denied  { mmap_zero } for  pid=8716 comm="vbetool" scontext=unconfined_u:unconfined_r:vbetool_t:s0-s0:c0.c1023 tcontext=unconfined_u:unconfined_r:vbetool_t:s0-s0:c0.c1023 tclass=memprotect


type=SYSCALL msg=audit(1313075762.379:100): arch=x86_64 syscall=mmap success=no exit=EACCES a0=f000 a1=502 a2=7 a3=11 items=0 ppid=5272 pid=8716 auid=500 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=(none) ses=1 comm=vbetool exe=/usr/sbin/vbetool subj=unconfined_u:unconfined_r:vbetool_t:s0-s0:c0.c1023 key=(null)

Hash: vbetool,vbetool_t,vbetool_t,memprotect,mmap_zero

audit2allow

#============= vbetool_t ==============
#!!!! This avc can be allowed using the boolean 'mmap_low_allowed'

allow vbetool_t self:memprotect mmap_zero;

audit2allow -R

#============= vbetool_t ==============
#!!!! This avc can be allowed using the boolean 'mmap_low_allowed'

allow vbetool_t self:memprotect mmap_zero;

Comment 1 Daniel Walsh 2011-08-11 15:21:29 UTC
Probably best solution is to 

yum remove vbetool

You probably do not need it.

Otherwise the alert tells you what you can do.