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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 39E33C3A5A3 for ; Tue, 27 Aug 2019 08:00:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 118A722CF4 for ; Tue, 27 Aug 2019 08:00:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566892838; bh=/zzZA9U0vrszr+exayCqiwcHv1WS9ZwywmCOOuoNULQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=iNez3Ajmk/O0T24hjsmLiqN7j1LOqmuurpaE4ENzPTx6OXSrJvID/esv1NA0ennJJ 1Lmmm966tAThcn7/fgzDV5VHxG0OGCkmX8j+x5TqxTTuYRJrjdC+aA9ZFTXz7ZbFZi 6T1rlWDL34exqvNyGX9giZ9JCY9HfRJW1wZ9Mu8U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729675AbfH0IAg (ORCPT ); Tue, 27 Aug 2019 04:00:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:55656 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731534AbfH0IAg (ORCPT ); Tue, 27 Aug 2019 04:00:36 -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 5998D217F5; Tue, 27 Aug 2019 08:00:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566892834; bh=/zzZA9U0vrszr+exayCqiwcHv1WS9ZwywmCOOuoNULQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=H98oh5wUvli8zyGKyXeK8sv+nn0giu8oDgLiYEdsNOdgaQmptmnHssFQqkDuVtaoD x/HEk88exjmuZT38Hk55Scyqk5LXYoKTHxOpSeb+oB8SF/pZwZklvZ3ICO8Y0E6K2Y ixVlZbaf2afgY/BeJ4wyXhFzlYu46wViVbHx5jcg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Magnus Karlsson , Ilya Maximets , Andrii Nakryiko , Alexei Starovoitov , Sasha Levin Subject: [PATCH 5.2 031/162] libbpf: fix using uninitialized ioctl results Date: Tue, 27 Aug 2019 09:49:19 +0200 Message-Id: <20190827072739.375906444@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190827072738.093683223@linuxfoundation.org> References: <20190827072738.093683223@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit decb705e01a5d325c9876b9674043cde4b54f0db ] 'channels.max_combined' initialized only on ioctl success and errno is only valid on ioctl failure. The code doesn't produce any runtime issues, but makes memory sanitizers angry: Conditional jump or move depends on uninitialised value(s) at 0x55C056F: xsk_get_max_queues (xsk.c:336) by 0x55C05B2: xsk_create_bpf_maps (xsk.c:354) by 0x55C089F: xsk_setup_xdp_prog (xsk.c:447) by 0x55C0E57: xsk_socket__create (xsk.c:601) Uninitialised value was created by a stack allocation at 0x55C04CD: xsk_get_max_queues (xsk.c:318) Additionally fixed warning on uninitialized bytes in ioctl arguments: Syscall param ioctl(SIOCETHTOOL) points to uninitialised byte(s) at 0x648D45B: ioctl (in /usr/lib64/libc-2.28.so) by 0x55C0546: xsk_get_max_queues (xsk.c:330) by 0x55C05B2: xsk_create_bpf_maps (xsk.c:354) by 0x55C089F: xsk_setup_xdp_prog (xsk.c:447) by 0x55C0E57: xsk_socket__create (xsk.c:601) Address 0x1ffefff378 is on thread 1's stack in frame #1, created by xsk_get_max_queues (xsk.c:318) Uninitialised value was created by a stack allocation at 0x55C04CD: xsk_get_max_queues (xsk.c:318) CC: Magnus Karlsson Fixes: 1cad07884239 ("libbpf: add support for using AF_XDP sockets") Signed-off-by: Ilya Maximets Acked-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- tools/lib/bpf/xsk.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/tools/lib/bpf/xsk.c b/tools/lib/bpf/xsk.c index ca272c5b67f47..8e03b65830da0 100644 --- a/tools/lib/bpf/xsk.c +++ b/tools/lib/bpf/xsk.c @@ -327,15 +327,14 @@ static int xsk_load_xdp_prog(struct xsk_socket *xsk) static int xsk_get_max_queues(struct xsk_socket *xsk) { - struct ethtool_channels channels; - struct ifreq ifr; + struct ethtool_channels channels = { .cmd = ETHTOOL_GCHANNELS }; + struct ifreq ifr = {}; int fd, err, ret; fd = socket(AF_INET, SOCK_DGRAM, 0); if (fd < 0) return -errno; - channels.cmd = ETHTOOL_GCHANNELS; ifr.ifr_data = (void *)&channels; strncpy(ifr.ifr_name, xsk->ifname, IFNAMSIZ - 1); ifr.ifr_name[IFNAMSIZ - 1] = '\0'; @@ -345,7 +344,7 @@ static int xsk_get_max_queues(struct xsk_socket *xsk) goto out; } - if (channels.max_combined == 0 || errno == EOPNOTSUPP) + if (err || channels.max_combined == 0) /* If the device says it has no channels, then all traffic * is sent to a single stream, so max queues = 1. */ -- 2.20.1