From: zohar@linux.vnet.ibm.com (Mimi Zohar) Date: Sun, 24 Dec 2017 00:12:08 -0500 Subject: [PATCH 11/11] evm: Don't update hmacs in user ns mounts In-Reply-To: <20171223040348.GK6837@mail.hallyn.com> References: <1f2233a1a028f1eb1e9bea7d06efa6d34e69e752.1512041070.git.dongsu@kinvolk.io> <20171223040348.GK6837@mail.hallyn.com> Message-ID: <1514092328.5221.116.camel@linux.vnet.ibm.com> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org Hi Serge, On Fri, 2017-12-22 at 22:03 -0600, Serge E. Hallyn wrote: > On Fri, Dec 22, 2017 at 03:32:35PM +0100, Dongsu Park wrote: > > From: Seth Forshee > > > > 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 > > Hi Mimi, > > does this change seem sufficient to you? I think this is the correct behavior in the context of fuse file systems. ?This patch, the "ima: define a new policy option named force" patch, and an updated IMA policy should be upstreamed together. ?The cover letter should provide the motivation for these patches. Mimi > > > Cc: "Serge E. Hallyn" > > Signed-off-by: Seth Forshee > > Signed-off-by: Dongsu Park > > --- > > 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 bcd64baf..729f4545 100644 > > --- a/security/integrity/evm/evm_crypto.c > > +++ b/security/integrity/evm/evm_crypto.c > > @@ -190,7 +190,8 @@ static int evm_calc_hmac_or_hash(struct dentry *dentry, > > int error; > > int size; > > > > - 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); > > -- > > 2.13.6 > -- 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