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=-7.0 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 95D2CC4CEC5 for ; Fri, 13 Sep 2019 13:09:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 696E62089F for ; Fri, 13 Sep 2019 13:09:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568380190; bh=1pmlV45ktfC1VY7yBHoN5Af05k7xkCDG8Mfc3NnN3DY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=LraxGA81d2fQ4rHrh1nvaTdXRRgKxBkbkiAGz4ft5ylyK44UsnRl4wU8T3N40s+O7 c64Hm/GCIpT7GdaPtr03SOy5Z4xsg+QYLcXSgVqx23pFEc67fJ00vtBhc+YIQF+lEZ 63annFuEQuf+PU/9PW3hwBPbeGbgYC7uYEGu57vU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388599AbfIMNJt (ORCPT ); Fri, 13 Sep 2019 09:09:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:34446 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388579AbfIMNJp (ORCPT ); Fri, 13 Sep 2019 09:09:45 -0400 Received: from localhost (unknown [104.132.45.99]) (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 E7F61206BB; Fri, 13 Sep 2019 13:09:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1568380184; bh=1pmlV45ktfC1VY7yBHoN5Af05k7xkCDG8Mfc3NnN3DY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iRuGfo0yK5LFDSwi1UTQcyLAz+TePU/C34tfghm+3SepX522LKfQRBnIZF4EewSex 09rroNnVxaU05OwDhQ9vUySgroiQU6rLWhj0yfCUjp8VWthd2Gg2KHEgohoNHuHdI8 D9BT/7S5v4j1a8tk7aN2fYAKRdirEnlHVYa32mqw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot , Sven Eckelmann , Simon Wunderlich Subject: [PATCH 4.9 09/14] batman-adv: fix uninit-value in batadv_netlink_get_ifindex() Date: Fri, 13 Sep 2019 14:07:02 +0100 Message-Id: <20190913130445.428043103@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190913130440.264749443@linuxfoundation.org> References: <20190913130440.264749443@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: Eric Dumazet commit 3ee1bb7aae97324ec9078da1f00cb2176919563f upstream. batadv_netlink_get_ifindex() needs to make sure user passed a correct u32 attribute. syzbot reported : BUG: KMSAN: uninit-value in batadv_netlink_dump_hardif+0x70d/0x880 net/batman-adv/netlink.c:968 CPU: 1 PID: 11705 Comm: syz-executor888 Not tainted 5.1.0+ #1 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x191/0x1f0 lib/dump_stack.c:113 kmsan_report+0x130/0x2a0 mm/kmsan/kmsan.c:622 __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:310 batadv_netlink_dump_hardif+0x70d/0x880 net/batman-adv/netlink.c:968 genl_lock_dumpit+0xc6/0x130 net/netlink/genetlink.c:482 netlink_dump+0xa84/0x1ab0 net/netlink/af_netlink.c:2253 __netlink_dump_start+0xa3a/0xb30 net/netlink/af_netlink.c:2361 genl_family_rcv_msg net/netlink/genetlink.c:550 [inline] genl_rcv_msg+0xfc1/0x1a40 net/netlink/genetlink.c:627 netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2486 genl_rcv+0x63/0x80 net/netlink/genetlink.c:638 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1337 netlink_sendmsg+0x127e/0x12f0 net/netlink/af_netlink.c:1926 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg net/socket.c:661 [inline] ___sys_sendmsg+0xcc6/0x1200 net/socket.c:2260 __sys_sendmsg net/socket.c:2298 [inline] __do_sys_sendmsg net/socket.c:2307 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2305 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2305 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x440209 Fixes: b60620cf567b ("batman-adv: netlink: hardif query") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Greg Kroah-Hartman --- net/batman-adv/netlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/batman-adv/netlink.c +++ b/net/batman-adv/netlink.c @@ -114,7 +114,7 @@ batadv_netlink_get_ifindex(const struct { struct nlattr *attr = nlmsg_find_attr(nlh, GENL_HDRLEN, attrtype); - return attr ? nla_get_u32(attr) : 0; + return (attr && nla_len(attr) == sizeof(u32)) ? nla_get_u32(attr) : 0; } /**