Defensive directory-tree walk might be too defensive

[4z3]

Since upgrading to 3.5.0, unreadable directories cause unexpected behavior.

Exhibit 1: filters don't get applied when unreadable directories are involved

$ mkdir -p /tmp/intermediary/src
$ sudo chown root: /tmp/intermediary
$ sudo chmod 711 /tmp/intermediary
$ echo - derp > /tmp/intermediary/src/.rsync-filter
$ touch /tmp/intermediary/src/derp
$ rsync --itemize-changes -aF /tmp/intermediary/src/ /tmp/dst/
>f..t...... .rsync-filter
>f..t...... derp  <---- should not be transferred

Exhibit 2: destination below unreadable directory cannot be used

$ mkdir -p /tmp/intermediary2/src /tmp/intermediary2/dst
$ sudo chown root: /tmp/intermediary2
$ sudo chmod 711 /tmp/intermediary2
$ rsync -a /tmp/intermediary2/src/ /tmp/intermediary2/dst
rsync: [Receiver] change_dir#1 "/tmp/intermediary2/dst" failed: Permission denied (13)
rsync error: errors selecting input/output files, dirs (code 3) at main.c(768) [Receiver=3.5.0]

Both cases execute as expected when making /tmp/intermediary* readable or using --insecure-links.

[steadytao]

Thank you for the report. Seems resolved by #1065, if you could verify with current master.