linux-kernel - Re: [PATCH -mm] unionfs: build fixes

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: <200807300100.m6U10R8A015358@agora.fsl.cs.sunysb.edu>
Date:	Tue, 29 Jul 2008 21:00:27 -0400
From:	Erez Zadok <ezk@...sunysb.edu>
To:	Hugh Dickins <hugh@...itas.com>
Cc:	Andrew Morton <akpm@...ux-foundation.org>,
	Erez Zadok <ezk@...sunysb.edu>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH -mm] unionfs: build fixes 

In message <Pine.LNX.4.64.0807291907440.13365@...nde.site>, Hugh Dickins writes:
> Get unionfs building and working in mmotm with the 2.6.27-rc1 VFS changes:
> permission() has been replaced by inode_permission() without nameidata arg;
> unionfs_permission() without nameidata arg; vfs_symlink() without mode arg;
> LOOKUP_ACCESS no longer defined; and kmem_cache_create() no longer passes
> kmem_cachep to the init_once() constructor.
> 
> Note: while okay for inclusion in -mm for now, unionfs_permission() mods
> will need review and perhaps correction by Erez: without a nameidata arg,
> some locking vanishes from unionfs_permission(), and a MNT_NOEXEC check on
> its lower_inode; I have not studied the VFS changes enough to tell whether
> that amounts to a real issue for unionfs, or just removal of dead code.

Thanks Hugh.  You beat me by few hours. :-) I've been testing similar fixes
for several days already (and was waiting for the dust to settle in the
merge window, b/c patches flying b/t linus's tree, -next, and -mm).

I've also looked at the inode_permission() locking, and tested it, and I
think it should be safe as long as the refcnt on the inode doesn't go to
zero.  In fact, I think unionfs_permission can be possibly further trimmed.

> Signed-off-by: Hugh Dickins <hugh@...itas.com>
> Cc: Erez Zadok <ezk@...sunysb.edu>
> ---
> This should follow git-unionfs.patch
> I notice my unionfs-fix-memory-leak.patch
> and fsstack-fsstack_copy_inode_size-locking.patch
> are currently commented out, yet I don't recall the
> mm-commits dispatch rider bringing me a telegram to explain why?

Both of those patches are in my tree now (not yet pushed to korg).

Note: your fsstack-fsstack_copy_inode_size-locking patch should really go to
mainline, but the one you sent depends on code in unionfs.  So temporarily
I'm folding it into my tree.  In a couple of days (once I switch from using
git to something like quilt) I'll extract it out into a separate patch which
can be applied cleanly against linux-next, so that Andrew can hopefully send
it upstream.

Erez.
--
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/