From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 E07C4C2D0F0 for ; Wed, 1 Apr 2020 16:31:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B7BCF214D8 for ; Wed, 1 Apr 2020 16:31:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585758698; bh=AABPsAeS0WRMB4og4yRTksa1AlhSg3dQrMGyJCKVP4o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Jwb5MtofL2b316S9RqmqIQm7Cj2LiOuZav+ueA4P5SO3xiasGIq4vEUW+fjWCfbBr IRzxdqk1nGChh3Kb4jc22gl7Xvx9fo7sS5mfe17EN2DCbaIk+H3w+J4qd2+76feVfH N1SaNMX/+NbJ6JEw2nFh4W5Fc9n+OMfuX5Ra7qXQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388297AbgDAQbh (ORCPT ); Wed, 1 Apr 2020 12:31:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:57672 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388268AbgDAQb1 (ORCPT ); Wed, 1 Apr 2020 12:31:27 -0400 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 857E221582; Wed, 1 Apr 2020 16:31:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585758686; bh=AABPsAeS0WRMB4og4yRTksa1AlhSg3dQrMGyJCKVP4o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uaQLsueOzp0ePOhLJXFXE/xK6j0hCRI//gt4qAfqa4oidaXcIqV7UoG3QeNRdxctT 5xunwQgiOtwq9Ws56x/pOxI4i74o9/FlWu9YawGF9yAPwl3k4gXXvgEMft0e+E4Upt ORHs+Y/LDyZOfSONQlWf3qG8AKhNGCVErupLl7Xo= 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?Eugenio=20P=C3=A9rez?= , "Michael S. Tsirkin" , "David S. Miller" , Sasha Levin Subject: [PATCH 4.4 44/91] vhost: Check docket sk_family instead of call getname Date: Wed, 1 Apr 2020 18:17:40 +0200 Message-Id: <20200401161528.834152308@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200401161512.917494101@linuxfoundation.org> References: <20200401161512.917494101@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eugenio Pérez [ Upstream commit 42d84c8490f9f0931786f1623191fcab397c3d64 ] 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: Sasha Levin --- drivers/vhost/net.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 1459dc9fd7010..5efac33c29dcb 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -815,11 +815,7 @@ static int vhost_net_release(struct inode *inode, struct file *f) static struct socket *get_raw_socket(int fd) { - struct { - struct sockaddr_ll sa; - char buf[MAX_ADDR_LEN]; - } uaddr; - int uaddr_len = sizeof uaddr, r; + int r; struct socket *sock = sockfd_lookup(fd, &r); if (!sock) @@ -831,12 +827,7 @@ static struct socket *get_raw_socket(int fd) goto err; } - r = sock->ops->getname(sock, (struct sockaddr *)&uaddr.sa, - &uaddr_len, 0); - if (r) - goto err; - - if (uaddr.sa.sll_family != AF_PACKET) { + if (sock->sk->sk_family != AF_PACKET) { r = -EPFNOSUPPORT; goto err; } -- 2.20.1