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

Francis Shim belfrancis2001 at yahoo.ca
Mon May 16 20:23:21 UTC 2011


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 skype /var/log/audit/audit.log | audit2allow -M mypol
# semodule -i mypol.pp

Additional Information:
Source Context                unconfined_u:unconfined_r:unconfined_execmem_t:s0-
                              s0:c0.c1023
Target Context                unconfined_u:unconfined_r:unconfined_execmem_t:s0-
                              s0:c0.c1023
Target Objects                Unknown [ memprotect ]
Source                        skype
Source Path                   /usr/bin/skype
Port                          <Unknown>
Host                          mobile-pc.localdomain
Source RPM Packages           
Target RPM Packages           
Policy RPM                    selinux-policy-3.9.7-40.fc14
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     mobile-pc.localdomain
Platform                      Linux mobile-pc.localdomain
                              2.6.35.13-91.fc14.i686.PAE #1 SMP Tue May 3
                              13:29:55 UTC 2011 i686 i686
Alert Count                   100
First Seen                    Mon 16 May 2011 03:37:35 PM EDT
Last Seen                     Mon 16 May 2011 03:37:35 PM EDT
Local ID                      162a1493-50dc-4231-ad0f-808d6fe5330b

Raw Audit Messages
type=AVC msg=audit(1305574655.789:127): avc:  denied  { mmap_zero } for  pid=2784 comm="skype" 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


Hash: skype,unconfined_execmem_t,unconfined_execmem_t,memprotect,mmap_zero

audit2allow

#============= unconfined_execmem_t ==============
#!!!! This avc is allowed in the current policy

allow unconfined_execmem_t self:memprotect mmap_zero;

audit2allow -R

#============= unconfined_execmem_t ==============
#!!!! This avc is allowed in the current policy

allow unconfined_execmem_t self:memprotect mmap_zero;





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