Ubuntu – Mount on filesystem of type eCryptfs explicitly disallowed due to known incompatibilities

ecryptfsencryptionmount

I get this error when I'm trying to do sudo mount -t ecryptfs folder1 folder2 in my home folder (encrypted by ubuntu)
I tried the same command but folders at /tmp, it worked as expected.

The error message I got:

  ecryptfs_unlink_sigs
  ecryptfs_key_bytes=16
  ecryptfs_cipher=aes
  ecryptfs_sig=66cea2017ad38853
Error mounting eCryptfs: [-22] Invalid argument

In /var/log/syslog:

kernel: [  197.621331] Mount on filesystem of type eCryptfs explicitly disallowed due to known incompatibilities
mount.ecryptfs: Failed to perform eCryptfs mount: [Invalid argument]
kernel: [  197.659287] Reading sb failed; rc = [-22]

Best Answer

You mentioned that your home folder is "encrypted by Ubuntu" -- it's actually encrypted using eCryptfs. Check the output of:

grep $HOME /proc/mounts

Nesting encrypted directories inside of encrypted directories is not supported with eCryptfs. Sorry.

Full disclosure: I'm one of the authors and current maintainers of eCryptfs.

Related Solutions

Ubuntu – Ecryptfs – mount: mount(2) failed: No such file or directory

Run the ecryptfs add passphrase command with the filename encryption key (if you're encrypting the filenames)

ecryptfs-add-passphrase --fnek

Ubuntu – problem with ecryptfs-recover-private: mount(2) failed

So this simple command ecryptfs-recover-private, proved to be unreliable. None of the metohd above worked for me, trying to move from ecryptfs to LUKS container.

What did work, was the manual method describe in ubuntu community wiki

In detail:

# sudo -i
# ecryptfs-add-passphrase --fnek 
Inserted auth tok with sig [aaaaaaaaaaaaa] into the user session keyring 
Inserted auth tok with sig [bbbbbbbbbbbbb] into the user session keyring  
# mkdir -p /mnt/new_mount_point  
# mount -t ecryptfs /mnt/old_mount_point/home/username/.Private /mnt/new_mount_point

select 3 (use a passphrase key type, and use your recovered passphrase aka unwrapped-passphrase)
select aes (use the aes cipher)
select 16 (use a 16 byte key)
enable plaintext passthrough: n
enable filename encryption: y

Best Answer

Related Solutions

Ubuntu – Ecryptfs – mount: mount(2) failed: No such file or directory

Ubuntu – problem with ecryptfs-recover-private: mount(2) failed

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