From mboxrd@z Thu Jan 1 00:00:00 1970 From: Theodore Ts'o Subject: Re: [PATCH] fscrypto: add authorization check for setting encryption policy Date: Fri, 9 Sep 2016 23:37:59 -0400 Message-ID: <20160910033759.qsvg4loedccqc7if@thunk.org> References: <1473357429-134444-1-git-send-email-ebiggers@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-f2fs@vger.kernel.org, jaegeuk@kernel.org To: Eric Biggers Return-path: Received: from imap.thunk.org ([74.207.234.97]:35640 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753073AbcIJDiz (ORCPT ); Fri, 9 Sep 2016 23:38:55 -0400 Content-Disposition: inline In-Reply-To: <1473357429-134444-1-git-send-email-ebiggers@google.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Thu, Sep 08, 2016 at 10:57:08AM -0700, Eric Biggers wrote: > On an ext4 or f2fs filesystem with file encryption supported, a user > could set an encryption policy on any empty directory(*) to which they > had readonly access. This is obviously problematic, since such a > directory might be owned by another user and the new encryption policy > would prevent that other user from creating files in their own directory > (for example). > > Fix this by requiring inode_owner_or_capable() permission to set an > encryption policy. This means that either the caller must own the file, > or the caller must have the capability CAP_FOWNER. > > (*) Or also on any regular file, for f2fs v4.6 and later and ext4 > v4.8-rc1 and later; a separate bug fix is coming for that. > > Signed-off-by: Eric Biggers > Cc: stable@vger.kernel.org # 4.1+; check fs/{ext4,f2fs} Thanks, applied. (Jaeguk, I plan to send this to Linus via the ext4.git tree as a fix for v4.8) - Ted