From patchwork Tue Mar 3 17:42:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 230034 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6AB46C3F2D7 for ; Tue, 3 Mar 2020 17:50:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3B56920CC7 for ; Tue, 3 Mar 2020 17:50:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583257802; bh=EJaw7nSihU84X6HW/kSe1Dq4ngkgNCk0RFoO+OkqYWU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=BsGx7qos+PyAFFQHlyhzPYS3Rj5xKR6w2/neGVeJlKkrTdwmhrFLCVpNE9HyOCkgc mgG8q4b4aX7abustOkCTcubUGso7Pa/tNZz5grYyOmQs7lA1sp2iyPzRr6E5DqJDjE eLwWeIg6T65Q+VQpvPsRPkhHgw8ptv307Wi7iyqU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731162AbgCCRuB (ORCPT ); Tue, 3 Mar 2020 12:50:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:57400 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730851AbgCCRt7 (ORCPT ); Tue, 3 Mar 2020 12:49:59 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DB58F20CC7; Tue, 3 Mar 2020 17:49:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583257799; bh=EJaw7nSihU84X6HW/kSe1Dq4ngkgNCk0RFoO+OkqYWU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kAHp2XMxl04S7Zt/CMH35SBEGwQ+/cbibptKRgSJgPL63E3ZspPQip95WkAP0AqW9 TuWIrcnkA8zbr0VvBYFkRxgUalJh3udCZbCMvfSFGgYzIQ4/vSUUwlhtAl7LXeWTjA jNA0Qlu6BqITA/ZqJkJVAyfj2gzniZikorzSEuwA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+f2a62d07a5198c819c7b@syzkaller.appspotmail.com, =?utf-8?q?Euge?= =?utf-8?q?nio_P=C3=A9rez?= , "Michael S. Tsirkin" , "David S. Miller" Subject: [PATCH 5.5 104/176] vhost: Check docket sk_family instead of call getname Date: Tue, 3 Mar 2020 18:42:48 +0100 Message-Id: <20200303174316.875453851@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200303174304.593872177@linuxfoundation.org> References: <20200303174304.593872177@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eugenio Pérez commit 42d84c8490f9f0931786f1623191fcab397c3d64 upstream. Doing so, we save one call to get data we already have in the struct. Also, since there is no guarantee that getname use sockaddr_ll parameter beyond its size, we add a little bit of security here. It should do not do beyond MAX_ADDR_LEN, but syzbot found that ax25_getname writes more (72 bytes, the size of full_sockaddr_ax25, versus 20 + 32 bytes of sockaddr_ll + MAX_ADDR_LEN in syzbot repro). Fixes: 3a4d5c94e9593 ("vhost_net: a kernel-level virtio server") Reported-by: syzbot+f2a62d07a5198c819c7b@syzkaller.appspotmail.com Signed-off-by: Eugenio Pérez Acked-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/vhost/net.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-) --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -1414,10 +1414,6 @@ static int vhost_net_release(struct inod static struct socket *get_raw_socket(int fd) { - struct { - struct sockaddr_ll sa; - char buf[MAX_ADDR_LEN]; - } uaddr; int r; struct socket *sock = sockfd_lookup(fd, &r); @@ -1430,11 +1426,7 @@ static struct socket *get_raw_socket(int goto err; } - r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, 0); - if (r < 0) - goto err; - - if (uaddr.sa.sll_family != AF_PACKET) { + if (sock->sk->sk_family != AF_PACKET) { r = -EPFNOSUPPORT; goto err; }