linux-kernel - Re: fanotify as syscalls

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: <200909222338.32646.agruen@suse.de>
Date:	Tue, 22 Sep 2009 23:38:32 +0200
From:	Andreas Gruenbacher <agruen@...e.de>
To:	Eric Paris <eparis@...hat.com>
Cc:	Jamie Lokier <jamie@...reable.org>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Evgeniy Polyakov <zbr@...emap.net>,
	David Miller <davem@...emloft.net>,
	linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
	netdev@...r.kernel.org, viro@...iv.linux.org.uk,
	alan@...ux.intel.com, hch@...radead.org
Subject: Re: fanotify as syscalls

On Tuesday, 22 September 2009 23:06:16 Eric Paris wrote:
> this is true, if there is only one namespace subtree notification works
> the same as global notification.
>
> [...]
>
> I don't see how subtree notification can possibly solve the global
> notification problem.

I'm thinking of is something like this: A listener registers interest in "/", 
recursively. The kernel sets a FSNOTIFY_WATCH_RECURSIVE flag on "/" and each 
mount point below. Afterwards when something is mounted anywhere, same 
namespace or not, the kernel sets the new mount's FSNOTIFY_WATCH_RECURSIVE 
flag if the parent mount has this flag set.

(Of course we need per fsnotify_group flags and not global ones, but this 
doesn't change the principle.)

Andreas
--
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/