Bug 702851

Summary: SELinux is preventing /usr/bin/vlc from using the 'execstack' accesses on a process.
Product: [Fedora] Fedora Reporter: Tom <thomasbelvin>
Component: selinux-policyAssignee: Miroslav Grepl <mgrepl>
Status: CLOSED NOTABUG QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: unspecified    
Version: rawhideCC: dwalsh, mgrepl
Target Milestone: ---   
Target Release: ---   
Hardware: i386   
OS: Linux   
Whiteboard: setroubleshoot_trace_hash:7eb1d41e92e014bb44f1f83d65d3a7642ddd35d9da49f7d4b822d71217d58092
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-05-09 16:04:21 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 Tom 2011-05-07 17:35:20 UTC
SELinux is preventing /usr/bin/vlc from using the 'execstack' accesses on a process.

*****  Plugin allow_execstack (53.1 confidence) suggests  ********************

If you believe that 
None
should not require execstack
Then you should clear the execstack flag and see if /usr/bin/vlc works correctly.
Report this as a bug on None.
You can clear the exestack flag by executing:
Do
execstack -c None

*****  Plugin catchall_boolean (42.6 confidence) suggests  *******************

If you want to allow unconfined executables to make their stack executable.  This should never, ever be necessary. Probably indicates a badly coded executable, but could indicate an attack. This executable should be reported in bugzilla
Then you must tell SELinux about this by enabling the 'allow_execstack' boolean.
Do
setsebool -P allow_execstack 1

*****  Plugin catchall (5.76 confidence) suggests  ***************************

If you believe that vlc should be allowed execstack access on processes labeled unconfined_t 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 vlc /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp

Additional Information:
Source Context                unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1
                              023
Target Context                unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1
                              023
Target Objects                Unknown [ process ]
Source                        vlc
Source Path                   /usr/bin/vlc
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           vlc-core-1.1.9-1.fc15
Target RPM Packages           
Policy RPM                    selinux-policy-3.9.16-20.fc16
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     (removed)
Platform                      Linux (removed) 2.6.39-0.rc6.git0.0.fc16.i686.PAE
                              #1 SMP Wed May 4 16:02:15 UTC 2011 i686 i686
Alert Count                   9
First Seen                    Sat 07 May 2011 01:33:53 PM EDT
Last Seen                     Sat 07 May 2011 01:35:03 PM EDT
Local ID                      1a8e0913-7363-419e-9017-77f6629efcf3

Raw Audit Messages
type=AVC msg=audit(1304789703.987:104): avc:  denied  { execstack } for  pid=1825 comm="vlc" scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tclass=process


type=SYSCALL msg=audit(1304789703.987:104): arch=i386 syscall=mprotect success=no exit=EACCES a0=bfafc000 a1=1000 a2=1000007 a3=b717ca24 items=0 ppid=1337 pid=1825 auid=500 uid=500 gid=500 euid=500 suid=500 fsuid=500 egid=500 sgid=500 fsgid=500 tty=(none) ses=1 comm=vlc exe=/usr/bin/vlc subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)

Hash: vlc,unconfined_t,unconfined_t,process,execstack

audit2allow

#============= unconfined_t ==============
#!!!! This avc can be allowed using the boolean 'allow_execstack'

allow unconfined_t self:process execstack;

audit2allow -R

#============= unconfined_t ==============
#!!!! This avc can be allowed using the boolean 'allow_execstack'

allow unconfined_t self:process execstack;

Comment 1 Miroslav Grepl 2011-05-09 16:04:21 UTC
You could look for libraries that are marked as requiring execstack

# find /lib -exec execstack -q {} \; -print 2> /dev/null | grep ^X 
# find /usr/lib -exec execstack -q {} \; -print 2> /dev/null | grep ^X 

or

# find /lib64 -exec execstack -q {} \; -print 2> /dev/null | grep ^X 
# find /usr/lib64 -exec execstack -q {} \; -print 2> /dev/null | grep ^X


Or you can turn this check off

setsebool -P allow_execstack 1