set svnauthz - cant browse the directory

[czg_e@…]

I've set my svnauthz file like: [groups] admin = root developer = czg

/ @admin =

Personal root = rw

Now,If root login,click browse source then prompt:Insufficient permissions to access / privileges are required to perform this operation.

if i edit svnauthz file like: [groups] admin = root developer = czg

/ @admin =r

Personal root = rw

then it's ok.

If you want to read the directory ,must owner parent directory of read??

my question is not install issue.