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=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 F2689C43219 for ; Tue, 30 Apr 2019 11:41:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C2B2521670 for ; Tue, 30 Apr 2019 11:41:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556624467; bh=J0ShUQzD1srjF3bzW26x95MrxhY7MvI01lJ6PQT1qB4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ymGrVG2RjVv2bWYodjDuCGtzdOLmNVx6rLDVPIwO8ythKfvLou0Ntcxlt7yKTmL2Q /CiVLrnA58yQ/c6G8rpr/RTIlWRV53UdC/q+Ur5JM4b5dwTX6ZJPvcBQ8WkhmCKd3c 0mRo/Ni9FJsWeEywAdpSA9hykjc80bWjxkshrYEg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728779AbfD3LlG (ORCPT ); Tue, 30 Apr 2019 07:41:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:48010 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727730AbfD3LlB (ORCPT ); Tue, 30 Apr 2019 07:41:01 -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 23D6B21734; Tue, 30 Apr 2019 11:40:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556624460; bh=J0ShUQzD1srjF3bzW26x95MrxhY7MvI01lJ6PQT1qB4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LZVXc4ov0lAHZXocFF4vnuyo+6CyRweBmg8ALnuTNJGybeFnibZLLjlSIRQfefKLQ 8CSAtZyJU7f0Bz6Iu/6K66oJtbd5IdDRfMUT1j7o/KPopDtCWo3ySm6ShEeHWXm0Wt C0r57OpaUIQPUTkvnDr4corWAgOi5c+OdNdVpNH8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+8b707430713eb46e1e45@syzkaller.appspotmail.com, Xin Long , "David S. Miller" Subject: [PATCH 4.9 27/41] tipc: check bearer name with right length in tipc_nl_compat_bearer_enable Date: Tue, 30 Apr 2019 13:38:38 +0200 Message-Id: <20190430113531.206287981@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190430113524.451237916@linuxfoundation.org> References: <20190430113524.451237916@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: Xin Long commit 6f07e5f06c8712acc423485f657799fc8e11e56c upstream. Syzbot reported the following crash: BUG: KMSAN: uninit-value in memchr+0xce/0x110 lib/string.c:961 memchr+0xce/0x110 lib/string.c:961 string_is_valid net/tipc/netlink_compat.c:176 [inline] tipc_nl_compat_bearer_enable+0x2c4/0x910 net/tipc/netlink_compat.c:401 __tipc_nl_compat_doit net/tipc/netlink_compat.c:321 [inline] tipc_nl_compat_doit+0x3aa/0xaf0 net/tipc/netlink_compat.c:354 tipc_nl_compat_handle net/tipc/netlink_compat.c:1162 [inline] tipc_nl_compat_recv+0x1ae7/0x2750 net/tipc/netlink_compat.c:1265 genl_family_rcv_msg net/netlink/genetlink.c:601 [inline] genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626 netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2477 genl_rcv+0x63/0x80 net/netlink/genetlink.c:637 netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline] netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1336 netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg net/socket.c:632 [inline] Uninit was created at: __alloc_skb+0x309/0xa20 net/core/skbuff.c:208 alloc_skb include/linux/skbuff.h:1012 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline] netlink_sendmsg+0xb82/0x1300 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:622 [inline] sock_sendmsg net/socket.c:632 [inline] It was triggered when the bearer name size < TIPC_MAX_BEARER_NAME, it would check with a wrong len/TLV_GET_DATA_LEN(msg->req), which also includes priority and disc_domain length. This patch is to fix it by checking it with a right length: 'TLV_GET_DATA_LEN(msg->req) - offsetof(struct tipc_bearer_config, name)'. Reported-by: syzbot+8b707430713eb46e1e45@syzkaller.appspotmail.com Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/tipc/netlink_compat.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/net/tipc/netlink_compat.c +++ b/net/tipc/netlink_compat.c @@ -394,7 +394,12 @@ static int tipc_nl_compat_bearer_enable( if (!bearer) return -EMSGSIZE; - len = min_t(int, TLV_GET_DATA_LEN(msg->req), TIPC_MAX_BEARER_NAME); + len = TLV_GET_DATA_LEN(msg->req); + len -= offsetof(struct tipc_bearer_config, name); + if (len <= 0) + return -EINVAL; + + len = min_t(int, len, TIPC_MAX_BEARER_NAME); if (!string_is_valid(b->name, len)) return -EINVAL;