From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754856AbdJINTF (ORCPT ); Mon, 9 Oct 2017 09:19:05 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43462 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754288AbdJINTB (ORCPT ); Mon, 9 Oct 2017 09:19:01 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Mateusz Jurczyk" , "Julian Wiedmann" , "David S. Miller" Date: Mon, 09 Oct 2017 13:30:34 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 14/74] af_iucv: Move sockaddr length checks to before accessing sa_family in bind and connect handlers In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.94-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Mateusz Jurczyk commit e3c42b61ff813921ba58cfc0019e3fd63f651190 upstream. Verify that the caller-provided sockaddr structure is large enough to contain the sa_family field, before accessing it in bind() and connect() handlers of the AF_IUCV socket. Since neither syscall enforces a minimum size of the corresponding memory region, very short sockaddrs (zero or one byte long) result in operating on uninitialized memory while referencing .sa_family. Fixes: 52a82e23b9f2 ("af_iucv: Validate socket address length in iucv_sock_bind()") Signed-off-by: Mateusz Jurczyk [jwi: removed unneeded null-check for addr] Signed-off-by: Julian Wiedmann Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- net/iucv/af_iucv.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) --- a/net/iucv/af_iucv.c +++ b/net/iucv/af_iucv.c @@ -705,10 +705,8 @@ static int iucv_sock_bind(struct socket char uid[9]; /* Verify the input sockaddr */ - if (!addr || addr->sa_family != AF_IUCV) - return -EINVAL; - - if (addr_len < sizeof(struct sockaddr_iucv)) + if (addr_len < sizeof(struct sockaddr_iucv) || + addr->sa_family != AF_IUCV) return -EINVAL; lock_sock(sk); @@ -879,7 +877,7 @@ static int iucv_sock_connect(struct sock struct iucv_sock *iucv = iucv_sk(sk); int err; - if (addr->sa_family != AF_IUCV || alen < sizeof(struct sockaddr_iucv)) + if (alen < sizeof(struct sockaddr_iucv) || addr->sa_family != AF_IUCV) return -EINVAL; if (sk->sk_state != IUCV_OPEN && sk->sk_state != IUCV_BOUND)