Java Application gets permission denied error in Linux

murphaph

Hi all,
I am having a little trouble understanding a problem.

I have a java web app (actually an admin type app to administer a site) running locally on tomcat (under Eclipse).

The admin app allows you to upload a graphic which is then saved on a server share (via a locally mounted directory).

We all mount the server share locally and specify it in our build (maven settings.xml-not relevant to the problem anyway).

When I attempt to upload a graphic using the app, I get a java exception:

java.io.FileNotFoundException: /mnt/java/devstorage/content/category/icon/nav_photo.png (Permission denied)

...and I see the file name there where it should be BUT it's got zero bytes, it's empty, so it hasn't saved.

/mnt/java/devstorage/content/category/icon/ is the local mount point-saving anything here means it is saved on the remote server so we can all see it in the team.

If I start ecllipse as root, the thing works so it's a permissions problem for sure but if I (not as root) attempt to copy a file to /mnt/java/devstorage/content/category/icon/ then it also works.

Has anybody got any ideas?

srsly78

chmod the directory. Also chown the pre-existing 0byte file if it's owned by root.

murphaph

srsly78 wrote: »

chmod the directory. Also chown the pre-existing 0byte file if it's owned by root.

The destination directory /mnt/java/devstorage/content/category/icon/ is already 777 and the 0 byte file is owned by my own user, not root. Any other ideas?

pmurphy@T420 /mnt/java/devstorage/content/category $ ls -l
total 0
drwxrwxrwx 2 1003 1003 0 2012-06-27 16:57 icon

pmurphy@T420 ~/cat icons $ ls -l
total 24
-rw-rw-r-- 1 pmurphy pmurphy 414 2012-06-27 12:27 nav_home.png
-rw-rw-r-- 1 pmurphy pmurphy 409 2012-06-27 12:27 nav_pc.png
-rw-rw-r-- 1 pmurphy pmurphy 471 2012-06-27 12:27 nav_phone.png
-rw-rw-r-- 1 pmurphy pmurphy 724 2012-06-27 12:27 nav_photo.png
-rw-rw-r-- 1 pmurphy pmurphy 806 2012-06-27 12:27 nav_software.png
-rw-rw-r-- 1 pmurphy pmurphy 295 2012-06-27 12:27 nav_tablet.png

srsly78

The files needs to have 777 as well if another user is trying to overwrite the file?

murphaph

srsly78 wrote: »

The files needs to have 777 as well if another user is trying to overwrite the file?

I don't know how or why the files save like that (with those more restrictive permissions I mean).

Even if I copy a file by hand using cp from the source to the destination folder, they end up with those same permissions (more restrictive than they originally had):

rw-rw-r--

becomes

rw-r--r--

Why would that be?

srsly78

Ugh I'm a bit rusty in this area... But I seem to remember there being some umask thing that defines the default permissions a new file gets.

Some googling returns this, which may be helpful: http://www.cyberciti.biz/tips/understanding-linux-unix-umask-value-usage.html

You need to change the default umask for whichever user is creating those files.

murphaph

srsly78 wrote: »

Ugh I'm a bit rusty in this area... But I seem to remember there being some umask thing that defines the default permissions a new file gets.

Some googling returns this, which may be helpful: http://www.cyberciti.biz/tips/understanding-linux-unix-umask-value-usage.html

You need to change the default umask for whichever user is creating those files.

Thanks, that looks like it might be the right way to go!

Feathers

murphaph wrote: »

The destination directory /mnt/java/devstorage/content/category/icon/ is already 777 and the 0 byte file is owned by my own user, not root. Any other ideas?

pmurphy@T420 /mnt/java/devstorage/content/category $ ls -l
total 0
drwxrwxrwx 2 1003 1003 0 2012-06-27 16:57 icon

pmurphy@T420 ~/cat icons $ ls -l
total 24
-rw-rw-r-- 1 pmurphy pmurphy 414 2012-06-27 12:27 nav_home.png
-rw-rw-r-- 1 pmurphy pmurphy 409 2012-06-27 12:27 nav_pc.png
-rw-rw-r-- 1 pmurphy pmurphy 471 2012-06-27 12:27 nav_phone.png
-rw-rw-r-- 1 pmurphy pmurphy 724 2012-06-27 12:27 nav_photo.png
-rw-rw-r-- 1 pmurphy pmurphy 806 2012-06-27 12:27 nav_software.png
-rw-rw-r-- 1 pmurphy pmurphy 295 2012-06-27 12:27 nav_tablet.png

Who owns the tomcat instance? Is it you, or have you set up a tomcat user that you could give ownership of the file to?