Bug 702903

Created attachment 497617 [details]
SElinux content for this alert.

Description of problem:mmap_zero alert via SElinux when open skype 2.2 the first time afer a reboot or a new pc star


Version-Release number of selected component (if applicable): Fedora 15 alpha


How reproducible:
just open skype after a restart or a new pc start

Steps to Reproduce:
1.
2.
3.
  
Actual results:


Expected results:


Additional info:
SELinux is preventing /usr/bin/skype from mmap_zero access on the memprotect Unknown.

*****  Plugin mmap_zero (53.1 confidence) suggests  **************************

If you do not think /usr/bin/skype 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 catchall_boolean (42.6 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 (5.76 confidence) suggests  ***************************

If you believe that skype 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 threaded-ml /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp

Additional Information:
Contesto della sorgente       unconfined_u:unconfined_r:unconfined_execmem_t:s0-
                              s0:c0.c1023
Contesto target               unconfined_u:unconfined_r:unconfined_execmem_t:s0-
                              s0:c0.c1023
Oggetti target                Unknown [ memprotect ]
Sorgente                      threaded-ml
Percorso della sorgente       /usr/bin/skype
Porta                         <Sconosciuto>
Host                          BlackSwan
Sorgente Pacchetti RPM        skype-2.2.0.25-fc10
Pacchetti RPM target          
RPM della policy              selinux-policy-3.9.16-23.fc15
Selinux abilitato             True
Tipo di policy                targeted
Modalità Enforcing            Enforcing
Host Name                     BlackSwan
Piattaforma                   Linux BlackSwan 2.6.38.5-24.fc15.i686 #1 SMP Fri
                              May 6 08:02:58 UTC 2011 i686 i686
Conteggio avvisi              211
Primo visto                   sab 07 mag 2011 10:02:20 CEST
Ultimo visto                  dom 08 mag 2011 09:50:20 CEST
ID locale                     ea4ea742-ac5c-400d-89fd-7aa4134ea2b3

Messaggi Raw Audit
type=AVC msg=audit(1304841020.288:178): avc:  denied  { mmap_zero } for  pid=2212 comm="threaded-ml" scontext=unconfined_u:unconfined_r:unconfined_execmem_t:s0-s0:c0.c1023 tcontext=unconfined_u:unconfined_r:unconfined_execmem_t:s0-s0:c0.c1023 tclass=memprotect


type=SYSCALL msg=audit(1304841020.288:178): arch=i386 syscall=mmap2 per=400000 success=no exit=EACCES a0=0 a1=1000 a2=3 a3=22 items=0 ppid=1571 pid=2212 auid=500 uid=500 gid=500 euid=500 suid=500 fsuid=500 egid=500 sgid=500 fsgid=500 tty=(none) ses=1 comm=threaded-ml exe=/usr/bin/skype subj=unconfined_u:unconfined_r:unconfined_execmem_t:s0-s0:c0.c1023 key=(null)

Hash: threaded-ml,unconfined_execmem_t,unconfined_execmem_t,memprotect,mmap_zero

audit2allow

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

allow unconfined_execmem_t self:memprotect mmap_zero;

audit2allow -R

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

allow unconfined_execmem_t self:memprotect mmap_zero;