linux-kernel - Re: [GIT PULL] vfs.git

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:	Thu, 11 Dec 2014 18:06:24 +0000
From:	Al Viro <viro@...IV.linux.org.uk>
To:	Miklos Szeredi <miklos@...redi.hu>
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>,
	LKML <linux-kernel@...r.kernel.org>,
	linux-fsdevel <linux-fsdevel@...r.kernel.org>
Subject: Re: [GIT PULL] vfs.git

On Thu, Dec 11, 2014 at 05:18:21PM +0100, Miklos Szeredi wrote:
> On Wed, Dec 10, 2014 at 8:13 PM, Al Viro <viro@...iv.linux.org.uk> wrote:
> 
> >         * killing a bunch of ->f_path.dentry users (and f_dentry macro).
> > Getting that completed will make life much simpler for unionmount/overlayfs,
> > since then we'll be able to limit the places sensitive to file _dentry_
> > to reasonably few.  Which allows to have file_inode(file) pointing to
> > inode in a covered layer, with dentry pointing to (negative) dentry in
> > union one.  Still not complete, but much closer now.
> 
> If we want f_path to point to union path, then shouldn't we be hiding
> it from all but core VFS?  Filesystems have no business looking at the
> mount anyway.  And looking at the union dentry will be just an endless
> source of bugs.
>
> Also some API changes are in order, like passing dentry to ->iterate()
> for "readdirplus" like operations, since f_path.dentry won't be usable
> for that purpose.  Alternatively replace f_inode with f_dentry and
> make file_inode() use that.

Check the remaining users of ->f_path.dentry.  I agree that they ought to
be encapsulated into a sane set of helpers - raw access to ->f_path in
filesystems is asking for serious trouble.  And we have very few such places
remaining.

FWIW, I would prefer to have the whole stack of underlying dentries reachable
in a uniform way...

PS: I'll send review of your multilayer stuff today.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/