Streams support in Linux

[Theodore Y. Ts'o]

On Sat, Aug 25, 2018 at 06:51:07AM -0700, Matthew Wilcox wrote:
> 
> Let's go over the properties of a file stream:
> 
>  - It has no life independent of the file it's attached to; you can't move
>    it from one file to another
>  - If the file is deleted, it is also deleted
>  - If the file is renamed, it travels with the file
>  - If the file is copied, the copying program decides whether any named
>    streams are copied along with it.
>  - Can be created, deleted.  Can be renamed?
>  - Openable, seekable, cachable
>  - Does not have sub-streams of its own
>  - Directories may also have streams which are distinct from the files
>    in the directory
>  - Can pipes / sockets / device nodes / symlinks / ... have streams?  Unclear.
>    Probably not useful.

Let's *not* make the mistakes Solaris did, and don't allow an fchdirat()
into a streams directory.  Let's also not allow executing
rootkits^H^H^H^H^H^H^H^H binaries as a stream.   :-)

			 	       - Ted