autofs/sshfs not adhere to remote permissions

Question

I have an ubuntu server "remote" with a user srichter. In my home dir on the server i have some files with different permissions like the following:

srichter@remote:~> ls -l

drwx------  13 srichter srichter     4096 Jun 16 22:48 secret
drwxr-xr-x  13 srichter users        4096 Feb 24 14:51 public

On my local machine i installed sshfs and fuse and everything to get autofs working. My local auto.master looks like this:

+auto.master # what's that line for?
/autofs/remote /etc/auto.remote.conf uid=srichter gid=srichter -v --ghost --timeout=30

the respective auto.remote.conf has the following content:

mnt -fstype=fuse,rw,nodev,noempty,noatime,allow_other,max_read=65536 :sshfs\#srichter@remote\:

this works like a charm: i can cd to /autofs/remote/mnt and ls -l gives me

drwx------  13 srichter srichter     4096 Jun 16 22:48 secret
drwxr-xr-x  13 srichter srichter     4096 Feb 24 14:51 public

Note, that only srichter should have acces to the secret directory. That's the problem. If i log in as guest on the local computer, i can cd to the secret dir and see (and edit) it's contents:

srichter@local:~> su guest
guest@local:~> groups
users
guest@local:~> cd /autofs/remote/mnt
guest@local:/autofs/remote/mnt> ls -l

drwx------  13 srichter srichter     4096 Jun 16 22:48 secret
drwxr-xr-x  13 srichter srichter     4096 Feb 24 14:51 public

guest@local:/autofs/remote/mnt> cd secret
guest@local:/autofs/remote/mnt/secret> ls -l

-rw-------   1 srichter srichter   470340 Jul  2  2012 secret.file1
-rw-------   1 srichter srichter  9547092 Jun  7 02:06 secret.file2

guest@local:/autofs/remote/mnt/secret> cat secret.file1

This is the content for secret.file1, which should not be visible to anyone but srichter.

So, why can guest access my files and what am i doing wrong?

Thank you in advance!

Answer 1

sshfs by default does not allow the kernel to check permissions

you need to use

sshfs -o allow_other,default_permissions

Im not sure how to use that with autofs as I only ever use sshfs direct but it should be able to slot in somewhere