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=-10.1 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,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 75A42C3A5AA for ; Wed, 4 Sep 2019 16:02:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4F34B23400 for ; Wed, 4 Sep 2019 16:02:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567612951; bh=uIJ/qXrVA5TDqANFCndn0F8SKWCcjEj0dGLzNlGQtWA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=bO+0my9bQfBElR5atZ4DaW/qX+EpKuxzvvmPR/kc//Om3LqYk0uJfJxC+4J/cdh0k 5pM9TuxiDiTg0zi1fruHT9jR9cqEolcc16ikOBUhqN29pliv2LB3nbodtLepXOOLI8 6OVLhkKMGiKtN5k/a7qteJirEcc5Orx5WKmnC4To= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733307AbfIDQCa (ORCPT ); Wed, 4 Sep 2019 12:02:30 -0400 Received: from mail.kernel.org ([198.145.29.99]:38464 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733289AbfIDQC2 (ORCPT ); Wed, 4 Sep 2019 12:02:28 -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 C95B123400; Wed, 4 Sep 2019 16:02:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567612947; bh=uIJ/qXrVA5TDqANFCndn0F8SKWCcjEj0dGLzNlGQtWA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dpNhKRBQcBaWmeHu35p6QqZ6BQF8J/rXuS1V79JAf3Gt/C7VmeMPYrNrZlDwEj5fR 2072kz0mSRjew0K1Fj0UuQjGwgu+pO34pWFfg+1zOND2DFhMoVDb3RcQ9S2pZqvQBL uxqys6apEppDbeyQb+SVdx0+QU3ISuyp+ZX6pV/c= 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 4.9 05/27] batman-adv: fix uninit-value in batadv_netlink_get_ifindex() Date: Wed, 4 Sep 2019 12:01:58 -0400 Message-Id: <20190904160220.4545-5-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190904160220.4545-1-sashal@kernel.org> References: <20190904160220.4545-1-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 64cb6acbe0a64..d7ba4fd24e3de 100644 --- a/net/batman-adv/netlink.c +++ b/net/batman-adv/netlink.c @@ -114,7 +114,7 @@ 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