From patchwork Wed May 12 14:47:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 436659 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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_NONE, 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 8EA48C18E7B for ; Wed, 12 May 2021 16:19:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B3A861D6C for ; Wed, 12 May 2021 16:19:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236162AbhELQUA (ORCPT ); Wed, 12 May 2021 12:20:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:49704 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236790AbhELQMg (ORCPT ); Wed, 12 May 2021 12:12:36 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 505D361D4E; Wed, 12 May 2021 15:41:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620834077; bh=7Jj4p4Ew1/jP+/8WWVsIZO8VRXusW8G6NW/eWRSipEc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=behMj0rzN4O5Lvbx6/0WlsspMO2Ef0QnNBEl3kb+txMtSMKCVVl/iehNjzNtlMCi9 j+mS7DhsCVW+DmKnuXSCpvG6+gC5syivzt2b96R9kPs/MczeKpOaijZKk4Ffeth7yb GSdYaG7lFjpv+JcDIX6e4Te85cuVT/ufk50xBc40= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Andrii Nakryiko , Alexei Starovoitov , Sasha Levin Subject: [PATCH 5.11 399/601] libbpf: Add explicit padding to bpf_xdp_set_link_opts Date: Wed, 12 May 2021 16:47:56 +0200 Message-Id: <20210512144840.946514354@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144827.811958675@linuxfoundation.org> References: <20210512144827.811958675@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Andrii Nakryiko [ Upstream commit dde7b3f5f2f458297aeccfd4783e53ab8ca046db ] Adding such anonymous padding fixes the issue with uninitialized portions of bpf_xdp_set_link_opts when using LIBBPF_DECLARE_OPTS macro with inline field initialization: DECLARE_LIBBPF_OPTS(bpf_xdp_set_link_opts, opts, .old_fd = -1); When such code is compiled in debug mode, compiler is generating code that leaves padding bytes uninitialized, which triggers error inside libbpf APIs that do strict zero initialization checks for OPTS structs. Adding anonymous padding field fixes the issue. Fixes: bd5ca3ef93cd ("libbpf: Add function to set link XDP fd while specifying old program") Signed-off-by: Andrii Nakryiko Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20210313210920.1959628-2-andrii@kernel.org Signed-off-by: Sasha Levin --- tools/lib/bpf/libbpf.h | 1 + 1 file changed, 1 insertion(+) diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h index 3c35eb401931..3d690d4e785c 100644 --- a/tools/lib/bpf/libbpf.h +++ b/tools/lib/bpf/libbpf.h @@ -507,6 +507,7 @@ struct xdp_link_info { struct bpf_xdp_set_link_opts { size_t sz; int old_fd; + size_t :0; }; #define bpf_xdp_set_link_opts__last_field old_fd