File corruption with unknown cause

[Redsandro]

I'm running Ubuntu 14.04 LTS with ecryptfs-utils 104-0ubuntu1.14.04.4, and I have a rather complex setup, although I am unsure the setup is related to the problem. I've been running this setup since Ubuntu 12.04 so I can sync encrypted files to the cloud.

I'm having my Documents synced across multiple computers. I have to mount ecryptfs outside of my home because my home is encrypted.

Setup on multiple computers:

/home/local/Documents.enc mounted on /home/local/Documents.unlocked
type ecryptfs
options rw,ecryptfs_cipher=aes,ecryptfs_key_bytes=32,ecryptfs_enable_filename_crypto=yes

/home/local/Documents.unlocked symlinked to /home/sander/Documents

/home/local/Documents.enc synced with OwnCloud

I've never experienced any problems before. But recently I've been noticing file corruption. I have no idea when this started. Never noticed it before. I was trying to chmod all my files in Documents and I had many errors like this:

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chmod: cannot access ‘./etc/(Klad)/Games Cheats/GTA San Andre\004’: No such file or directory
chmod: cannot access ‘./etc/(Klad)/Games Cheats/\236\343\355UQo!<\325’: No such file or directory
chmod: cannot access ‘./etc/(Klad)/Computers/\354"|\207\255\351\305a\027TA\037\250\222@\340\343’: No such file or directory
chmod: cannot access ‘./etc/(Klad)/Computers/\354\210\177\201\031\t\257GG\037\336\025m\313\317Pu’: No such file or directory
chmod: cannot access ‘./etc/(Klad)/Computers/Sand\a\255\003\276Iv;’: No such file or directory
chmod: cannot access ‘./etc/(Klad)/Computers/San\255\246\030\003\032\270\023[\266\363\r\250\003=3\343’: No such file or directory
chmod: cannot access ‘./etc/(Klad)/Computers/lin0\333Q>\367\376/\035\3254\220\206l\343\302?’: No such file or directory
chmod: cannot access ‘./etc/(Klad)/Computers/The BIOS Optimizatioمr\347\003E\251\355\336X\0200\376\276M\032’: No such file or directory
chmod: cannot access ‘./etc/(Klad)/(Uitzoeken)/m})ME\t\230\272*?U\324@\371\235Nz’: No such file or directory
chmod: cannot access ‘./etc/(Klad)/(Uitzoeken)/Boo\227\f\260\316\361\251\303o\221M\0372 \201\231{’: No such file or directory
chmod: cannot access ‘./etc/(Klad)/(Uitzoeken)/Backtracking EM\337\302lֹ\361\242ῴtA\351OR\273’: No such file or directory

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I thought something is screwing up the filenames. But the attributes and content are also messed up:

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$ ll
ls: cannot access �"|����aTA��@��: No such file or directory
ls: cannot access ��� �GG�m��Pu: No such file or directory
ls: cannot access Sand��Iv;: No such file or directory
�=3�: No such file or directory
ls: cannot access lin0�Q>��/
�4��l��?: No such file or directory
ls: cannot access The BIOS Optimizatioمr�E���X0��M: No such file or directory
total 1.2M
drwxr-s--- 2 sander sander 12K Mar 23 00:43 ./
drwxr-s--- 12 sander sander 4.0K Mar 23 00:46 ../
-rw-r----- 1 sander sander 637 Mar 8 2013 2003-07-01 Comp Specs.txt
-????????? ? ? ? ? ? ?"|????a?TA???@??
-rw-r----- 1 sander sander 6.4K Mar 8 2013 autostart.txt
-rw-r----- 1 sander sander 21K Mar 8 2013 Computer Salland.html
-????????? ? ? ? ? ? ???????GG???m??Pu
-rw-r----- 1 sander sander 2.3K Mar 8 2013 Journalling points.txt
-????????? ? ? ? ? ? lin0?Q>??/??4??l???
-rw-r----- 1 sander sander 748 Mar 8 2013 linux partities.txt
-rw-r----- 1 sander sander 2.5K Mar 8 2013 poorten.txt
-rw-r----- 1 sander sander 359 Mar 8 2013 Reformat protocol.txt
-????????? ? ? ? ? ? San???????[?????=3?
-rw-r----- 1 sander sander 133 Mar 8 2013 Sander HTMLtips.txt
-rw-r----- 1 sander sander 2.0K Mar 8 2013 Sander, lees mij.txt
-rw-r----- 1 sander sander 1.5K Mar 8 2013 Sander RegTweaks.txt
-????????? ? ? ? ? ? Sand????Iv;
-rw-r----- 1 sander sander 564 Mar 8 2013 San Windowstips.txt
-rw-r----- 1 sander sander 858 Mar 8 2013 StopServices.bat
-rw-r----- 1 sander sander 770K Mar 8 2013 The BIOS Optimization Guide v6.2.pdf
-????????? ? ? ? ? ? The BIOS Optimizatioمr??E???X?0??M?
-rw-r----- 1 sander sander 739 Mar 8 2013 Winprogs.txt
-rw-r----- 1 sander sander 12K Mar 8 2013 XP Services optimize.txt

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What changed over the months/years: Regular updates to Ubuntu, kernel updates, updates to ecryptfs-utils and a switch from Dropbox to OwnCloud at some point.

[Redsandro (redsandro)]

I'm not sure if this is OwnCloud or ecryptfs related, so I posted an OwnCloud issue here:
https://github.com/owncloud/core/issues/24416

[Tyler Hicks (tyhicks)]

Hi - Sorry to hear the trouble that you're having.

This setup is not supported by eCryptfs. The owncloud client is presumably making changes to /home/local/Documents.enc while the user is making changes to /home/sander/Documents. There's nothing keeping the filesystem object caches (page cache, inode cache, denty cache) for /home/local/Documents.enc in sync with the caches for /home/sander/Documents.