linux-kernel - Re: [PATCH v3 06/12] man/man2/fsconfig.2: document "new" mount API

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]

Message-ID: <198cc025823.ea44e3f585444.6907980660506284461@zohomail.com>
Date: Thu, 21 Aug 2025 13:42:42 +0400
From: Askar Safin <safinaskar@...omail.com>
To: "Aleksa Sarai" <cyphar@...har.com>
Cc: "Alejandro Colomar" <alx@...nel.org>,
	"Michael T. Kerrisk" <mtk.manpages@...il.com>,
	"Alexander Viro" <viro@...iv.linux.org.uk>,
	"Jan Kara" <jack@...e.cz>,
	"G. Branden Robinson" <g.branden.robinson@...il.com>,
	"linux-man" <linux-man@...r.kernel.org>,
	"linux-api" <linux-api@...r.kernel.org>,
	"linux-fsdevel" <linux-fsdevel@...r.kernel.org>,
	"linux-kernel" <linux-kernel@...r.kernel.org>,
	"David Howells" <dhowells@...hat.com>,
	"Christian Brauner" <brauner@...nel.org>
Subject: Re: [PATCH v3 06/12] man/man2/fsconfig.2: document "new" mount API

 ---- On Tue, 12 Aug 2025 22:25:40 +0400  Aleksa Sarai <cyphar@...har.com> wrote --- 
 > On 2025-08-09, Aleksa Sarai <cyphar@...har.com> wrote:
 > > +Note that the Linux kernel reuses filesystem instances
 > > +for many filesystems,
 > > +so (depending on the filesystem being configured and parameters used)
 > > +it is possible for the filesystem instance "created" by
 > > +.B \%FSCONFIG_CMD_CREATE
 > > +to, in fact, be a reference
 > > +to an existing filesystem instance in the kernel.
 > > +The kernel will attempt to merge the specified parameters
 > > +of this filesystem configuration context
 > > +with those of the filesystem instance being reused,
 > > +but some parameters may be
 > > +.IR "silently ignored" .
 > 
 > While looking at this again, I realised this explanation is almost
 > certainly incorrect in a few places (and was based on a misunderstanding
 > of how sget_fc() works and how it interacts with vfs_get_tree()).
 > 
 > I'll rewrite this in the next version.

This recent patch seems to be relevant:
https://lore.kernel.org/all/20250816-debugfs-mount-opts-v3-1-d271dad57b5b@posteo.net/

--
Askar Safin
https://types.pl/@safinaskar