linux-kernel - Re: [PATCH] fs: allow do_renameat2() over bind mounts of the same filesystem.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 28 Aug 2020 22:34:45 +0100
From:   Al Viro <viro@...iv.linux.org.uk>
To:     Florian Margaine <florian@...tform.sh>
Cc:     linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] fs: allow do_renameat2() over bind mounts of the same
 filesystem.

On Fri, Aug 28, 2020 at 10:40:35PM +0200, Florian Margaine wrote:
> There's currently this seemingly unnecessary limitation that rename()
> cannot work over bind mounts of the same filesystem,

... is absolutely deliberate - that's how you set a boundary in the
tree, preventing both links and renames across it.

Incidentally, doing that would have fun effects for anyone with current
directory inside the subtree you'd moved - try and see.