From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753595AbdFMSGR (ORCPT ); Tue, 13 Jun 2017 14:06:17 -0400 Received: from mail-wr0-f172.google.com ([209.85.128.172]:33993 "EHLO mail-wr0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751802AbdFMSGP (ORCPT ); Tue, 13 Jun 2017 14:06:15 -0400 From: Mateusz Jurczyk To: Dmitry Tarnyagin , "David S. Miller" Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] caif: Add sockaddr length check before accessing sa_family in connect handler Date: Tue, 13 Jun 2017 20:06:12 +0200 Message-Id: <20170613180612.11630-1-mjurczyk@google.com> X-Mailer: git-send-email 2.13.1.508.gb3defc5cc-goog Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Verify that the caller-provided sockaddr structure is large enough to contain the sa_family field, before accessing it in the connect() handler of the AF_CAIF socket. Since the syscall doesn't enforce 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. Signed-off-by: Mateusz Jurczyk --- net/caif/caif_socket.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/caif/caif_socket.c b/net/caif/caif_socket.c index adcad344c843..21f18ea2fce4 100644 --- a/net/caif/caif_socket.c +++ b/net/caif/caif_socket.c @@ -754,6 +754,10 @@ static int caif_connect(struct socket *sock, struct sockaddr *uaddr, lock_sock(sk); + err = -EINVAL; + if (addr_len < offsetofend(struct sockaddr, sa_family)) + goto out; + err = -EAFNOSUPPORT; if (uaddr->sa_family != AF_CAIF) goto out; -- 2.13.1.508.gb3defc5cc-goog