From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kara Subject: Re: [PATCH 0/5 v2] fs: Fixes for removing xid bits and security labels Date: Thu, 8 Jan 2015 10:18:32 +0100 Message-ID: <20150108091832.GA16551@quack.suse.cz> References: <1418906946-30695-1-git-send-email-jack@suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel@vger.kernel.org, xfs@oss.sgi.com, linux-security-module@vger.kernel.org, Jan Kara To: Al Viro Return-path: Received: from cantor2.suse.de ([195.135.220.15]:34482 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751050AbbAHJSh (ORCPT ); Thu, 8 Jan 2015 04:18:37 -0500 Content-Disposition: inline In-Reply-To: <1418906946-30695-1-git-send-email-jack@suse.cz> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Hello! Al, can you have a look at these fixes please? Thanks! Honza On Thu 18-12-14 13:49:01, Jan Kara wrote: > Hello, > > warning in XFS made me look into detail into how clearing of suid / sgid > bits and security labels is done. And I've spotted a few issues: > 1) MS_NOSEC handling is broken - we set it after each file_remove_suid() call. > However we needn't have removed suid bit simply because we have > CAP_SYS_FSID and further writes to the file from processes without this > capability still need to clear the suid bit. > 2) file_remove_suid() is a misnomer since it also handles removing of > security labels. It is even more confusing because should_remove_suid() > doesn't return whether file_remove_suid() is needed or not. > 3) On truncate we do clear suid bits but not security labels. According to > documentation in include/linux/security.h that's a bug but please correct > me if I'm wrong. > 4) ocfs2 doesn't clear security labels - hard to fix, I left it alone for now. > 5) XFS didn't provide proper exclusion for clearing mode bits. > > This series aims at fixing above issues. > > Since v1 I have removed bogus patch changing inode_set_flags(), I have > updated changelog of patch 4/5 to better explain why ->inode_killpriv should > be called and I have included a fix for MS_NOSEC handling in this series. > Al, can you please merge the patches? Thanks! > > Honza -- Jan Kara SUSE Labs, CR