From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:45344 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751874AbeECBnL (ORCPT ); Wed, 2 May 2018 21:43:11 -0400 Received: from pps.filterd (m0098399.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w431gZfm060348 for ; Wed, 2 May 2018 21:43:10 -0400 Received: from e06smtp10.uk.ibm.com (e06smtp10.uk.ibm.com [195.75.94.106]) by mx0a-001b2d01.pphosted.com with ESMTP id 2hqr509q9c-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 02 May 2018 21:43:10 -0400 Received: from localhost by e06smtp10.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 3 May 2018 02:43:08 +0100 Subject: Re: [PATCH] evm: Don't update hmacs in user ns mounts From: Mimi Zohar To: "Eric W. Biederman" Cc: linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, James Morris Date: Wed, 02 May 2018 21:43:03 -0400 In-Reply-To: <87r2mtybhf.fsf@xmission.com> References: <87r2mtybhf.fsf@xmission.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Message-Id: <1525311783.3238.19.camel@linux.vnet.ibm.com> Sender: linux-integrity-owner@vger.kernel.org List-ID: On Wed, 2018-05-02 at 16:49 -0500, Eric W. Biederman wrote: > From: Seth Forshee > Date: Fri, 22 Dec 2017 15:32:35 +0100 > > The kernel should not calculate new hmacs for mounts done by > non-root users. Update evm_calc_hmac_or_hash() to refuse to > calculate new hmacs for mounts for non-init user namespaces. > > Cc: linux-integrity@vger.kernel.org > Cc: linux-security-module@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Cc: James Morris > Cc: Mimi Zohar > Cc: "Serge E. Hallyn" > Signed-off-by: Seth Forshee > Signed-off-by: Dongsu Park > Signed-off-by: Eric W. Biederman > --- > > Mimi this patch has been floating around for a while and it appears to > be the only piece missing from the vfs to make unprivileged mounts safe > (at least semantically). Do you want to merge this through your integrity > tree or should merge this through my userns tree? Matthew's EVM patches don't conflict with this change, so either way is fine. Mimi > > security/integrity/evm/evm_crypto.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > > diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c > index a46fba322340..facf9cdd577d 100644 > --- a/security/integrity/evm/evm_crypto.c > +++ b/security/integrity/evm/evm_crypto.c > @@ -200,7 +200,8 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry, > int size; > bool ima_present = false; > > - if (!(inode->i_opflags & IOP_XATTR)) > + if (!(inode->i_opflags & IOP_XATTR) || > + inode->i_sb->s_user_ns != &init_user_ns) > return -EOPNOTSUPP; > > desc = init_desc(type); From mboxrd@z Thu Jan 1 00:00:00 1970 From: zohar@linux.vnet.ibm.com (Mimi Zohar) Date: Wed, 02 May 2018 21:43:03 -0400 Subject: [PATCH] evm: Don't update hmacs in user ns mounts In-Reply-To: <87r2mtybhf.fsf@xmission.com> References: <87r2mtybhf.fsf@xmission.com> Message-ID: <1525311783.3238.19.camel@linux.vnet.ibm.com> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org On Wed, 2018-05-02 at 16:49 -0500, Eric W. Biederman wrote: > From: Seth Forshee > Date: Fri, 22 Dec 2017 15:32:35 +0100 > > The kernel should not calculate new hmacs for mounts done by > non-root users. Update evm_calc_hmac_or_hash() to refuse to > calculate new hmacs for mounts for non-init user namespaces. > > Cc: linux-integrity at vger.kernel.org > Cc: linux-security-module at vger.kernel.org > Cc: linux-kernel at vger.kernel.org > Cc: James Morris > Cc: Mimi Zohar > Cc: "Serge E. Hallyn" > Signed-off-by: Seth Forshee > Signed-off-by: Dongsu Park > Signed-off-by: Eric W. Biederman > --- > > Mimi this patch has been floating around for a while and it appears to > be the only piece missing from the vfs to make unprivileged mounts safe > (at least semantically). Do you want to merge this through your integrity > tree or should merge this through my userns tree? Matthew's EVM patches don't conflict with this change, so either way is fine. Mimi > > security/integrity/evm/evm_crypto.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > > diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c > index a46fba322340..facf9cdd577d 100644 > --- a/security/integrity/evm/evm_crypto.c > +++ b/security/integrity/evm/evm_crypto.c > @@ -200,7 +200,8 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry, > int size; > bool ima_present = false; > > - if (!(inode->i_opflags & IOP_XATTR)) > + if (!(inode->i_opflags & IOP_XATTR) || > + inode->i_sb->s_user_ns != &init_user_ns) > return -EOPNOTSUPP; > > desc = init_desc(type); -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html