When you setup a share with VirtualBox – normally – it is only accessible to root (the priviledged user that mounted it).
To give other users access to that share add (append) the group vboxsf – to the existing groups (note: important to append with the -a switch so that you do not lose existing groups.
The example below:
- shows the “oracle” linux user does not have access to the share / group vboxsf
- provides access to vboxsf group – the group that provides accesss to virtualbox additions shares
- shows that the group vboxsf has been added to to the users groups – providing access to the share
uid=54321(oracle) gid=54321(oinstall) groups=54321(oinstall),54322(dba)
usermod -aG vboxsf oracle
uid=54321(oracle) gid=54321(oinstall) groups=54321(oinstall),54322(dba),492(vboxsf)