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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8B423C64EC4 for ; Fri, 10 Mar 2023 14:17:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231769AbjCJORh (ORCPT ); Fri, 10 Mar 2023 09:17:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58504 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232036AbjCJORT (ORCPT ); Fri, 10 Mar 2023 09:17:19 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6E2721188EB for ; Fri, 10 Mar 2023 06:16:17 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 8B4E0B822AD for ; Fri, 10 Mar 2023 14:16:16 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CC310C433EF; Fri, 10 Mar 2023 14:16:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678457775; bh=r3R0pKyDDLULWjJjRmPaBgwtEd0dbnEJV2wAA1P6tEE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=V++u5FxOvVpcNnsTLx1QWgVjXruNQmfQ4npAJDtuQCVfvfVRwTFr8OX2SHu4G5GtQ Epa39JvA7mkVV51j/VZCrgaLhgd1ZvESJuOS5u2oCk/3XsiiEGiScJ1qkfJ7HXWti/ e2uHjE47flyUiAtDtgyOZiXCZAgc5ZIdxyKhg1kE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ilya Leoshkevich , Andrii Nakryiko , Sasha Levin Subject: [PATCH 4.19 052/252] libbpf: Fix alen calculation in libbpf_nla_dump_errormsg() Date: Fri, 10 Mar 2023 14:37:02 +0100 Message-Id: <20230310133720.384966750@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230310133718.803482157@linuxfoundation.org> References: <20230310133718.803482157@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Ilya Leoshkevich [ Upstream commit 17bcd27a08a21397698edf143084d7c87ce17946 ] The code assumes that everything that comes after nlmsgerr are nlattrs. When calculating their size, it does not account for the initial nlmsghdr. This may lead to accessing uninitialized memory. Fixes: bbf48c18ee0c ("libbpf: add error reporting in XDP") Signed-off-by: Ilya Leoshkevich Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20230210001210.395194-8-iii@linux.ibm.com Signed-off-by: Sasha Levin --- tools/lib/bpf/nlattr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/lib/bpf/nlattr.c b/tools/lib/bpf/nlattr.c index 4719434278b20..ac979b4290559 100644 --- a/tools/lib/bpf/nlattr.c +++ b/tools/lib/bpf/nlattr.c @@ -170,7 +170,7 @@ int nla_dump_errormsg(struct nlmsghdr *nlh) hlen += nlmsg_len(&err->msg); attr = (struct nlattr *) ((void *) err + hlen); - alen = nlh->nlmsg_len - hlen; + alen = (void *)nlh + nlh->nlmsg_len - (void *)attr; if (nla_parse(tb, NLMSGERR_ATTR_MAX, attr, alen, extack_policy) != 0) { fprintf(stderr, -- 2.39.2