Alert tells you what to do.


*****  Plugin restorecon (99.5 confidence) suggests   ************************

If you want to fix the label. 
/var/lib/snapd/snap/core/2381/lib64/ld-linux-x86-64.so.2 default label should be snappy_var_lib_t.
Then you can run restorecon. The access attempt may have been stopped due to insufficient permissions to access a parent directory in which case try to change the following command accordingly.
Do
# /sbin/restorecon -v /var/lib/snapd/snap/core/2381/lib64/ld-linux-x86-64.so.2





restorecon -R -v /var/lib

is probably not a bad idea.

The alerts' suggestion doesn't seem to work here because that file is actually in a squashfs volume.  Should the warning be changed or should a different suggestion be presented? 

$ sudo /sbin/restorecon -v /var/lib/snapd/snap/core/2381/lib64/ld-linux-x86-64.so.2                                                                                   /sbin/restorecon: Could not set context for /var/lib/snapd/snap/core/2381/lib64/ld-linux-x86-64.so.2:  Read-only file system


$ mount | grep snapd                                                                                                                                                               /var/lib/snapd/snaps/core_2381.snap on /var/lib/snapd/snap/core/2381 type squashfs (ro,nodev,relatime,seclabel)
tmpfs on /run/snapd/ns type tmpfs (rw,nosuid,nodev,seclabel,mode=755)
nsfs on /run/snapd/ns/core.mnt type nsfs (rw,seclabel)
/var/lib/snapd/snaps/micro_1.snap on /var/lib/snapd/snap/micro/1 type squashfs (ro,nodev,relatime,seclabel)
nsfs on /run/snapd/ns/micro.mnt type nsfs (rw,seclabel)

This file system does not have labels on it. if you could mount the file system with a context omunt we could probably fix the AVC.

Something like

-o context="system_u:object_r:usr_t:s0"  

ALthough if this is a standard diretory for snappy to install then it should have a label on it like snapd_var_lib_t.  Which is a bug in SELinux policy.

I assume this is a standard directory. I installed snapd with:

sudo dnf install snapd

Then attempted to install the following snap with:

sudo snap install micro --beta

I then tried another snap:

sudo snap install vlc

This gets me a different alert:

SELinux is preventing systemctl from create access on the lnk_file var-lib-snapd-snap-vlc-4.mount.

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

If you believe that systemctl should be allowed create access on the var-lib-snapd-snap-vlc-4.mount lnk_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 'systemctl' --raw | audit2allow -M my-systemctl
# semodule -X 300 -i my-systemctl.pp

Additional Information:
Source Context                system_u:system_r:snappy_t:s0
Target Context                system_u:object_r:systemd_unit_file_t:s0
Target Objects                var-lib-snapd-snap-vlc-4.mount [ lnk_file ]
Source                        systemctl
Source Path                   systemctl
Port                          <Unknown>
Host                          agalloch
Source RPM Packages           
Target RPM Packages           
Policy RPM                    selinux-policy-3.13.1-260.1.fc26.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     agalloch
Platform                      Linux agalloch 4.11.11-300.fc26.x86_64 #1 SMP Mon
                              Jul 17 16:32:11 UTC 2017 x86_64 x86_64
Alert Count                   1
First Seen                    2017-07-26 17:46:41 AEST
Last Seen                     2017-07-26 17:46:41 AEST
Local ID                      57b937c7-7942-44c4-9f53-2f60b72151ed

Raw Audit Messages
type=AVC msg=audit(1501055201.930:1312): avc:  denied  { create } for  pid=20001 comm="systemctl" name="var-lib-snapd-snap-vlc-4.mount" scontext=system_u:system_r:snappy_t:s0 tcontext=system_u:object_r:systemd_unit_file_t:s0 tclass=lnk_file permissive=1


Hash: systemctl,snappy_t,systemd_unit_file_t,lnk_file,create

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I have the same error in Fedora 39. This never got fixed.