Description of problem:
SELinux is preventing sosreport from 'relabelto' accesses on the file limits.

*****  Plugin associate (99.5 confidence) suggests   *************************

If you want to change the label of limits to dnsmasq_t, you are not allowed to since it is not a valid file type.
Then you must pick a valid file label.
Do
select a valid file type.  List valid file labels by executing: 
# seinfo -afile_type -x

*****  Plugin catchall (1.49 confidence) suggests   **************************

If you believe that sosreport should be allowed relabelto access on the limits file 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:
# ausearch -c 'sosreport' --raw | audit2allow -M my-sosreport
# semodule -X 300 -i my-sosreport.pp

Additional Information:
Source Context                unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1
                              023
Target Context                system_u:system_r:dnsmasq_t:s0-s0:c0.c1023
Target Objects                limits [ file ]
Source                        sosreport
Source Path                   sosreport
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           
Target RPM Packages           
Policy RPM                    <Unknown>
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     (removed)
Platform                      Linux (removed) 4.11.11-300.fc26.x86_64 #1 SMP Mon
                              Jul 17 16:32:11 UTC 2017 x86_64 x86_64
Alert Count                   8
First Seen                    2017-09-05 16:16:30 EDT
Last Seen                     2017-09-06 10:45:44 EDT
Local ID                      8a6a802b-6983-4b48-b67b-ebf905a5f209

Raw Audit Messages
type=AVC msg=audit(1504709144.675:28026): avc:  denied  { relabelto } for  pid=25810 comm="sosreport" name="limits" dev="dm-12" ino=145972 scontext=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 tcontext=system_u:system_r:dnsmasq_t:s0-s0:c0.c1023 tclass=file permissive=0


Hash: sosreport,unconfined_t,dnsmasq_t,file,relabelto


Additional info:
component:      selinux-policy
reporter:       libreport-2.9.3
hashmarkername: setroubleshoot
kernel:         4.15.6-300.fc27.x86_64
type:           libreport