Bug 537699

Summary:

SELinux is preventing /lib/ld-2.11.90.so from making the program stack
executable.

Detailed Description:

The ld-linux.so.2 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 ld-linux.so.2 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
ld-linux.so.2 to run correctly, you can change the context of the executable to
execmem_exec_t. "chcon -t execmem_exec_t '/lib/ld-2.11.90.so'" 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
'/lib/ld-2.11.90.so'"

Fix Command:

chcon -t execmem_exec_t '/lib/ld-2.11.90.so'

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                        ld-linux.so.2
Source Path                   /lib/ld-2.11.90.so
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           glibc-2.11.90-1
Target RPM Packages           
Policy RPM                    selinux-policy-3.6.32-24.fc12
Selinux Enabled               True
Policy Type                   targeted
MLS Enabled                   True
Enforcing Mode                Enforcing
Plugin Name                   allow_execstack
Host Name                     (removed)
Platform                      Linux (removed) 2.6.31.1-56.fc12.x86_64 #1 SMP Tue Sep
                              29 16:16:22 EDT 2009 x86_64 x86_64
Alert Count                   1
First Seen                    Sun 15 Nov 2009 01:38:06 PM MST
Last Seen                     Sun 15 Nov 2009 01:38:06 PM MST
Local ID                      043fd07b-0cc1-405f-8540-71bbfd864688
Line Numbers                  

Raw Audit Messages            

node=(removed) type=AVC msg=audit(1258317486.100:20835): avc:  denied  { execstack } for  pid=25671 comm="ld-linux.so.2" 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(1258317486.100:20835): arch=40000003 syscall=125 success=no exit=-13 a0=ffd34000 a1=1000 a2=1000007 a3=ffd343c0 items=0 ppid=25670 pid=25671 auid=501 uid=501 gid=501 euid=501 suid=501 fsuid=501 egid=501 sgid=501 fsgid=501 tty=pts2 ses=1 comm="ld-linux.so.2" exe="/lib/ld-2.11.90.so" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)



Hash String generated from  selinux-policy-3.6.32-24.fc12,allow_execstack,ld-linux.so.2,unconfined_t,unconfined_t,process,execstack
audit2allow suggests:

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