Description of problem:
SELinux is preventing snapd from 'read' accesses on the directory snap.

*****  Plugin catchall (100. confidence) suggests   **************************

If you believe that snapd should be allowed read access on the snap directory 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 'snapd' --raw | audit2allow -M my-snapd
# semodule -X 300 -i my-snapd.pp

Additional Information:
Source Context                system_u:system_r:snappy_t:s0
Target Context                unconfined_u:object_r:user_home_t:s0
Target Objects                snap [ dir ]
Source                        snapd
Source Path                   snapd
Port                          <Unknown>
Host                          (removed)
Source RPM Packages           
Target RPM Packages           
Policy RPM                    selinux-policy-3.13.1-283.29.fc27.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     (removed)
Platform                      Linux (removed) 4.15.13-300.fc27.x86_64 #1 SMP Mon
                              Mar 26 19:06:57 UTC 2018 x86_64 x86_64
Alert Count                   4
First Seen                    2018-03-31 01:52:05 +0430
Last Seen                     2018-04-06 01:02:32 +0430
Local ID                      19cb8ab0-70bb-4c56-96d5-f3849b0164f1

Raw Audit Messages
type=AVC msg=audit(1522960352.996:426): avc:  denied  { read } for  pid=2022 comm="snapd" name="snap" dev="sda7" ino=14943032 scontext=system_u:system_r:snappy_t:s0 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=dir permissive=1


Hash: snapd,snappy_t,user_home_t,dir,read

Version-Release number of selected component:
selinux-policy-3.13.1-283.29.fc27.noarch

Additional info:
component:      selinux-policy
reporter:       libreport-2.9.3
hashmarkername: setroubleshoot
kernel:         4.15.13-300.fc27.x86_64
type:           libreport