We have an Ubuntu 10.04 server. How can I set it so that new files created (or copied) over SFTP or SSH have g+rw and g+rwx permissions (where appropriate)?

I'm also using setgid (chmod g+s) so that they inherit the proper group owner.


In /etc/ssh/sshd_config, you can pass a flag and value in (-u 0002) like the following to set the umask value:

Subsystem sftp /usr/lib/openssh/sftp-server -u 0002

Append the -u 0002 to the existing Subsystem sftp line of the configuration file.

Afterwards, you will need to restart ssh for the changes to take effect:

service ssh restart
  • This only applies to newer versions of OpenSSH, but should be the preferred solution where possible. – Andrew B Jan 12 '13 at 6:27
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    This only works if you need more restrictive permissions than what is set by the client, not more loose. – Joost Aug 19 '15 at 18:52
  • As Joost said, this doesn't help to force group-write permissions. I would help to forbid group-write. – flight Sep 10 '15 at 15:46
  • According to recent documentation, the same options can be used with Subsystem sftp internal-sftp. – underscore_d Oct 9 '15 at 12:27

In /etc/ssh/sshd_config, change the following:

Subsystem sftp /usr/lib/openssh/sftp-server


Subsystem sftp /bin/sh -c 'umask 0002; exec /usr/libexec/openssh/sftp-server'

Soure: http://jeff.robbins.ws/articles/setting-the-umask-for-sftp-transactions

  • 1
    It's better to put an exec before the final /usr/.../sftp-server, so that you won't have useless sh processes lying around. – user1686 Jun 13 '10 at 20:32
  • Also, an umask is just a number; 0002 can be written shorter as 02. – user1686 Jun 13 '10 at 20:33
  • I thought umask was an octal, but thanks for the exec part. – wag2639 Jun 16 '10 at 15:38
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    Yes, umasks are octal. That doesn't mean you need three leading zeroes - one is enough. (In fact, the umask command doesn't need any leading zeroes, it always reads the argument as an octal number.) ... But on the second thought, maybe 0002 is clearer to understand. – user1686 Jun 19 '10 at 20:52
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    This doesn't work for me. It won't enforce the g+w permission. – flight Sep 10 '15 at 15:54

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