Bug 583369

Summary: SELinux is preventing /usr/lib/RealPlayer11GOLD/realplay.bin from making the program stack executable.
Product: [Fedora] Fedora Reporter: nolimithottboy
Component: selinux-policyAssignee: Daniel Walsh <dwalsh>
Status: CLOSED DUPLICATE QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: low    
Version: 12CC: carlg, dwalsh, mgrepl, nolimithottboy
Target Milestone: ---   
Target Release: ---   
Hardware: i386   
OS: Linux   
Whiteboard: setroubleshoot_trace_hash:3573eb285ec1c06fb3c51ffc45eac90b9b42a3cd3b13417a2d09c67d70f764b5
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2010-04-19 02:14:15 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 nolimithottboy 2010-04-18 08:23:14 UTC
Summary:

SELinux is preventing /usr/lib/RealPlayer11GOLD/realplay.bin from making the
program stack executable.

Detailed Description:

The realplay application attempted to make its stack executable. This is a
potential security problem. This should never ever be necessary. Stack memory is
not executable on most OSes these days and this will not change. Executable
stack memory is one of the biggest security problems. An execstack error might
in fact be most likely raised by malicious code. Applications are sometimes
coded incorrectly and request this permission. The SELinux Memory Protection
Tests (http://people.redhat.com/drepper/selinux-mem.html) web page explains how
to remove this requirement. If realplay does not work and you need it to work,
you can configure SELinux temporarily to allow this access until the application
is fixed. Please file a bug report.

Allowing Access:

Sometimes a library is accidentally marked with the execstack flag, if you find
a library with this flag you can clear it with the execstack -c LIBRARY_PATH.
Then retry your application. If the app continues to not work, you can turn the
flag back on with execstack -s LIBRARY_PATH. Otherwise, if you trust realplay to
run correctly, you can change the context of the executable to execmem_exec_t.
"chcon -t execmem_exec_t '/usr/lib/RealPlayer11GOLD/realplay.bin'" You must also
change the default file context files on the system in order to preserve them
even on a full relabel. "semanage fcontext -a -t execmem_exec_t
'/usr/lib/RealPlayer11GOLD/realplay.bin'"

Fix Command:

chcon -t execmem_exec_t '/usr/lib/RealPlayer11GOLD/realplay.bin'

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                None [ process ]
Source                        realplay
Source Path                   /usr/lib/RealPlayer11GOLD/realplay.bin
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           RealPlayer-11-1pclos2007
Target RPM Packages           
Policy RPM                    selinux-policy-3.6.32-41.fc12
Selinux Enabled               True
Policy Type                   targeted
MLS Enabled                   True
Enforcing Mode                Enforcing
Plugin Name                   allow_execstack
Host Name                     (removed)
Platform                      Linux (removed) 2.6.31.5-127.fc12.i686.PAE #1
                              SMP Sat Nov 7 21:25:57 EST 2009 i686 athlon
Alert Count                   2
First Seen                    Sun 18 Apr 2010 12:22:28 AM CEST
Last Seen                     Sun 18 Apr 2010 12:22:28 AM CEST
Local ID                      72d283d4-9739-434e-aa10-1ed470b3f8a1
Line Numbers                  

Raw Audit Messages            

node=(removed) type=AVC msg=audit(1271542948.343:41): avc:  denied  { execstack } for  pid=2735 comm="realplay" scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tclass=process

node=(removed) type=SYSCALL msg=audit(1271542948.343:41): arch=40000003 syscall=125 success=no exit=-13 a0=bfdb7000 a1=1000 a2=1000007 a3=bfdb67a0 items=0 ppid=1 pid=2735 auid=500 uid=500 gid=0 euid=500 suid=500 fsuid=500 egid=0 sgid=0 fsgid=0 tty=(none) ses=1 comm="realplay" exe="/usr/lib/RealPlayer11GOLD/realplay.bin" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)



Hash String generated from  selinux-policy-3.6.32-41.fc12,allow_execstack,realplay,unconfined_t,unconfined_t,process,execstack
audit2allow suggests:

#============= unconfined_t ==============
allow unconfined_t self:process execstack;

Comment 1 Carl G. 2010-04-18 16:16:59 UTC
What is the label on realplayer ?

1)

Sometimes a library is accidentally marked with the execstack flag, if you find
a library with this flag you can clear it with the execstack -c LIBRARY_PATH.
Then retry your application. If the app continues to not work, you can turn the
flag back on with execstack -s LIBRARY_PATH.

2)
If it *still* doesn't work, try the fellowing command (not recommended)

chcon -t execmem_exec_t '/usr/lib/RealPlayer11GOLD/realplay.bin'

Policy RPM selinux-policy-3.6.32-41.fc12

You should update your system to benefit from the latest security updates / bugfix. Maybe this have been fixed in a newest release of SELinux too.

Comment 2 Daniel Walsh 2010-04-19 02:14:15 UTC

*** This bug has been marked as a duplicate of bug 533987 ***