From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:59558 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752777AbeENGxO (ORCPT ); Mon, 14 May 2018 02:53:14 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Dumazet , syzbot , "David S. Miller" Subject: [PATCH 4.4 34/56] net: fix rtnh_ok() Date: Mon, 14 May 2018 08:48:39 +0200 Message-Id: <20180514064758.079254201@linuxfoundation.org> In-Reply-To: <20180514064754.853201981@linuxfoundation.org> References: <20180514064754.853201981@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Dumazet commit b1993a2de12c9e75c35729e2ffbc3a92d50c0d31 upstream. syzbot reported : BUG: KMSAN: uninit-value in rtnh_ok include/net/nexthop.h:11 [inline] BUG: KMSAN: uninit-value in fib_count_nexthops net/ipv4/fib_semantics.c:469 [inline] BUG: KMSAN: uninit-value in fib_create_info+0x554/0x8d20 net/ipv4/fib_semantics.c:1091 @remaining is an integer, coming from user space. If it is negative we want rtnh_ok() to return false. Fixes: 4e902c57417c ("[IPv4]: FIB configuration using struct fib_config") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- include/net/nexthop.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/include/net/nexthop.h +++ b/include/net/nexthop.h @@ -6,7 +6,7 @@ static inline int rtnh_ok(const struct rtnexthop *rtnh, int remaining) { - return remaining >= sizeof(*rtnh) && + return remaining >= (int)sizeof(*rtnh) && rtnh->rtnh_len >= sizeof(*rtnh) && rtnh->rtnh_len <= remaining; }