From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:40646 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753698AbeBBRPB (ORCPT ); Fri, 2 Feb 2018 12:15:01 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot , Stephan Mueller , Herbert Xu Subject: [PATCH 4.15 15/55] crypto: af_alg - whitelist mask and type Date: Fri, 2 Feb 2018 17:58:33 +0100 Message-Id: <20180202140827.628846872@linuxfoundation.org> In-Reply-To: <20180202140826.117602411@linuxfoundation.org> References: <20180202140826.117602411@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stephan Mueller commit bb30b8848c85e18ca7e371d0a869e94b3e383bdf upstream. The user space interface allows specifying the type and mask field used to allocate the cipher. Only a subset of the possible flags are intended for user space. Therefore, white-list the allowed flags. In case the user space caller uses at least one non-allowed flag, EINVAL is returned. Reported-by: syzbot Signed-off-by: Stephan Mueller Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/af_alg.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -150,7 +150,7 @@ EXPORT_SYMBOL_GPL(af_alg_release_parent) static int alg_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len) { - const u32 forbidden = CRYPTO_ALG_INTERNAL; + const u32 allowed = CRYPTO_ALG_KERN_DRIVER_ONLY; struct sock *sk = sock->sk; struct alg_sock *ask = alg_sk(sk); struct sockaddr_alg *sa = (void *)uaddr; @@ -158,6 +158,10 @@ static int alg_bind(struct socket *sock, void *private; int err; + /* If caller uses non-allowed flag, return error. */ + if ((sa->salg_feat & ~allowed) || (sa->salg_mask & ~allowed)) + return -EINVAL; + if (sock->state == SS_CONNECTED) return -EINVAL; @@ -176,9 +180,7 @@ static int alg_bind(struct socket *sock, if (IS_ERR(type)) return PTR_ERR(type); - private = type->bind(sa->salg_name, - sa->salg_feat & ~forbidden, - sa->salg_mask & ~forbidden); + private = type->bind(sa->salg_name, sa->salg_feat, sa->salg_mask); if (IS_ERR(private)) { module_put(type->owner); return PTR_ERR(private);