From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from imap.thunk.org ([74.207.234.97]:44792 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726313AbeHYUF1 (ORCPT ); Sat, 25 Aug 2018 16:05:27 -0400 Date: Sat, 25 Aug 2018 12:25:47 -0400 From: "Theodore Y. Ts'o" To: Matthew Wilcox Cc: linux-fsdevel@vger.kernel.org, samba-technical@lists.samba.org, Eric Biggers Subject: Re: Streams support in Linux Message-ID: <20180825162547.GA10619@thunk.org> References: <20180825135107.GA12251@bombadil.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180825135107.GA12251@bombadil.infradead.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: 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