From mboxrd@z Thu Jan 1 00:00:00 1970 From: serge@hallyn.com (Serge E. Hallyn) Date: Fri, 22 Dec 2017 22:03:48 -0600 Subject: [PATCH 11/11] evm: Don't update hmacs in user ns mounts In-Reply-To: <1f2233a1a028f1eb1e9bea7d06efa6d34e69e752.1512041070.git.dongsu@kinvolk.io> References: <1f2233a1a028f1eb1e9bea7d06efa6d34e69e752.1512041070.git.dongsu@kinvolk.io> Message-ID: <20171223040348.GK6837@mail.hallyn.com> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org 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? > 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