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=-7.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNWANTED_LANGUAGE_BODY,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 B264DC3A5A9 for ; Wed, 4 Sep 2019 16:01:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8BBE923711 for ; Wed, 4 Sep 2019 16:01:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567612894; bh=GoxAEzNMR5z8osRHkwO6EZg8c+PsNlMxhxDqKZwGVP8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=XRtQx+ZJyEjflU7DpVf6vnre/8gv4WJBBdZPtJGoHUf7Qdq9QduZ4XJs0kRhg321w IZe06I71JzEKWZddfE6RgzRuiV1KI+Cpa0dcg2VGh/ngBbtD0rP4mXq6IcmGXKOBQd LeUzGQgNcMM0zmVSqrNnBnAIN3tHXTQ0p08ZNBAg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733027AbfIDQBd (ORCPT ); Wed, 4 Sep 2019 12:01:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:36910 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732404AbfIDQBb (ORCPT ); Wed, 4 Sep 2019 12:01:31 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 10EB02070C; Wed, 4 Sep 2019 16:01:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567612889; bh=GoxAEzNMR5z8osRHkwO6EZg8c+PsNlMxhxDqKZwGVP8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ls4LWQEqSM99EXOd8TwPgCet9yMx1Nj6aPxT2Zsg8/m0+Q9jfGfsSkh3itKwUMIfm aYkvi54Q5S3cYKOQ0i5OKfnH8cx6/8NFkzb2As1zN24rQocE0OhPM0T6H6jTcAuZLO fELJ9Y6taSLQ1jvRpd0GdCq4xpvvxSQtLSwpNrII= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eric Dumazet , syzbot , Sven Eckelmann , Simon Wunderlich , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 06/36] batman-adv: fix uninit-value in batadv_netlink_get_ifindex() Date: Wed, 4 Sep 2019 12:00:52 -0400 Message-Id: <20190904160122.4179-6-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190904160122.4179-1-sashal@kernel.org> References: <20190904160122.4179-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Eric Dumazet [ Upstream commit 3ee1bb7aae97324ec9078da1f00cb2176919563f ] 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: Sasha Levin --- net/batman-adv/netlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c index ab13b4d587338..edb35bcc046d4 100644 --- a/net/batman-adv/netlink.c +++ b/net/batman-adv/netlink.c @@ -110,7 +110,7 @@ batadv_netlink_get_ifindex(const struct nlmsghdr *nlh, int attrtype) { 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; } /** -- 2.20.1