From patchwork Fri Jun 28 14:31:15 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Andrew Cooper X-Patchwork-Id: 13716250 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2B3D9C30658 for ; Fri, 28 Jun 2024 14:31:38 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.750662.1158737 (Exim 4.92) (envelope-from ) id 1sNCdJ-0001yn-Qy; Fri, 28 Jun 2024 14:31:25 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 750662.1158737; Fri, 28 Jun 2024 14:31:25 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sNCdJ-0001xe-K0; Fri, 28 Jun 2024 14:31:25 +0000 Received: by outflank-mailman (input) for mailman id 750662; Fri, 28 Jun 2024 14:31:24 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1sNCdI-0001vg-PW for xen-devel@lists.xenproject.org; Fri, 28 Jun 2024 14:31:24 +0000 Received: from mail-ed1-x529.google.com (mail-ed1-x529.google.com [2a00:1450:4864:20::529]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id 1806494c-355b-11ef-90a3-e314d9c70b13; Fri, 28 Jun 2024 16:31:23 +0200 (CEST) Received: by mail-ed1-x529.google.com with SMTP id 4fb4d7f45d1cf-57d1d614049so953588a12.1 for ; Fri, 28 Jun 2024 07:31:23 -0700 (PDT) Received: from andrewcoop.eng.citrite.net ([160.101.139.1]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a72aaf63390sm84944566b.69.2024.06.28.07.31.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 28 Jun 2024 07:31:22 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 1806494c-355b-11ef-90a3-e314d9c70b13 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=citrix.com; s=google; t=1719585082; x=1720189882; darn=lists.xenproject.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=0HcoQ3jxCZ06h2GCy+THa2ZWR0EVbPJaxvXputzPwx0=; b=BziVxMbWZMiCPHzA6+OkT0V4E+B6qYrEQqWFeRux6NsXy/SUmDo4wLU0zafrpyCsVx nD2ZfNWSQMHlNYq5OVPGEutK2h9KHhD0SvDRUK0md+v94ol3E/30UvwulSqbJoQKWc67 6UVfsz2sF2jk5HYyxO0nXCSYFQVQYpe4A7tnY= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1719585082; x=1720189882; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=0HcoQ3jxCZ06h2GCy+THa2ZWR0EVbPJaxvXputzPwx0=; b=g+nUO7xHhvel+mBgPyKVVtCnGsCCHBMHsVypPDjIATT2zmZryP2ww46u3eayJsup3A sD4kQEntRgVpq46koieEzHsxOwuAHfL2XnpsgkEjpRmneHCoFWkntcItl+jzxgTvLUis SdFuvAhmC6YcRHZM/xL+PGFr+OmaMOj8oyZLUQ6HenoeZIoUCe1JiFA2mlum60c+1q/f kbFm64EMOgFaTsnF/y8vBQlW8YHZCBa/XUrboICzqUvdN4NV6tV4BvZU6cYyfs1/W9+h bW7SrrLe+saobajFHPk2/y7v59OiIO6hduV4Wc3o4x6bFQKRjkRLfD2L00vawzFToP67 3jww== X-Gm-Message-State: AOJu0YyykN652JVhpfgdjNsmzKnUB8xijy4F2GOQ4EC6ZPB3NEqyYoet fx8ilydrql/owRivU4k0eUIqRikLZe2m7Ago/Wxn0YPM2fV7kPLGHksHMBXrCVYGA/jtuxEhxyE h+dk= X-Google-Smtp-Source: AGHT+IF9o3Kg7jr3zKcI7qTmqOEqOBoKhlT5CXjFMwttb5naf+XjdFMl8lOQTAOMnf7ijdGKtzbaQw== X-Received: by 2002:a17:906:f59b:b0:a72:b34f:e15b with SMTP id a640c23a62f3a-a72b34fe2e9mr130747566b.57.1719585082472; Fri, 28 Jun 2024 07:31:22 -0700 (PDT) From: Andrew Cooper To: Xen-devel Cc: Andrew Cooper , Frediano Ziglio , Anthony PERARD , Juergen Gross , =?utf-8?q?Roger_Pau_Monn=C3=A9?= , Oleksii Kurochko Subject: [PATCH for-4.19 2/3] tools/libxs: Fix CLOEXEC handling in get_socket() Date: Fri, 28 Jun 2024 15:31:15 +0100 Message-Id: <20240628143116.1044976-3-andrew.cooper3@citrix.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240628143116.1044976-1-andrew.cooper3@citrix.com> References: <20240628143116.1044976-1-andrew.cooper3@citrix.com> MIME-Version: 1.0 get_socket() opens a socket, then uses fcntl() to set CLOEXEC. This is racy with exec(). Open the socket with SOCK_CLOEXEC. Use the same compatibility strategy as O_CLOEXEC on ancient versions of Linux. Reported-by: Frediano Ziglio Signed-off-by: Andrew Cooper --- CC: Anthony PERARD CC: Juergen Gross CC: Roger Pau Monné CC: Frediano Ziglio CC: Oleksii Kurochko --- tools/libs/store/xs.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/tools/libs/store/xs.c b/tools/libs/store/xs.c index 037e79d98b58..11a766c50887 100644 --- a/tools/libs/store/xs.c +++ b/tools/libs/store/xs.c @@ -44,6 +44,10 @@ #define O_CLOEXEC 0 #endif +#ifndef SOCK_CLOEXEC +#define SOCK_CLOEXEC 0 +#endif + struct xs_stored_msg { XEN_TAILQ_ENTRY(struct xs_stored_msg) list; struct xsd_sockmsg hdr; @@ -207,16 +211,14 @@ int xs_fileno(struct xs_handle *h) static int get_socket(const char *connect_to) { struct sockaddr_un addr; - int sock, saved_errno, flags; + int sock, saved_errno; - sock = socket(PF_UNIX, SOCK_STREAM, 0); + sock = socket(PF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0); if (sock < 0) return -1; - if ((flags = fcntl(sock, F_GETFD)) < 0) - goto error; - flags |= FD_CLOEXEC; - if (fcntl(sock, F_SETFD, flags) < 0) + /* Compat for non-SOCK_CLOEXEC environments. Racy. */ + if (!SOCK_CLOEXEC && !set_cloexec(sock)) goto error; addr.sun_family = AF_UNIX;