change owner of a file and it's parent directories

Question

I have a file that has 10 parent directories. When I change the file's owner with chown command new owner still can't write to file because the file's parent directories still have a different owner. Is there a way to also change parent directories' owner?

If not, what's the best way to temporarily grant a user permission to change a file inside nested directories?

Answer 1

The user only needs the execute bit present on a directory containing a file to be able to access the file. If the execute bit is set on the directory and the user has write permissions to the file he can edit that file. Without write perms on the directory he wont be able to create or delete files (even if he owns the file), but he will be able to edit them. Note though that without read permissions (only execute is set) the user wont be able to get a directory listing, he'll have to know the exact file name of the file to be able to access it.

So if our file is at dirname/filename.txt and user owns the file:

rwx--x--x dirname
User can edit dirname/filename.txt
User cannot create dirname/filename2.txt
User cannot delete dirname/filename.txt
User cannot ls dirname

rwxr-xr-x dirname
User can edit dirname/filename.txt
User cannot create dirname/filename2.txt
User cannot delete dirname/filename.txt
User can ls dirname

rwxrwxrwx dirname
User can do anything

NOTE
These rules do not apply if the directory has the sticky bit applied. The stick bit changes the behavior completely (the /tmp directory has the sticky bit applied).

Answer 2

To answer your question I could recommend the usage of ACLs Access Control Lists

Hope it helps!