From patchwork Tue Jun 1 15:57:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 12291687 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=-11.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MIME_BASE64_TEXT,SPF_HELO_NONE,SPF_PASS 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 71B9BC4708F for ; Tue, 1 Jun 2021 15:59:17 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C8706613AD for ; Tue, 1 Jun 2021 15:59:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C8706613AD Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:49412 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lo6nT-0000HO-Oe for qemu-devel@archiver.kernel.org; Tue, 01 Jun 2021 11:59:15 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:58846) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lo6mY-00070Z-H2 for qemu-devel@nongnu.org; Tue, 01 Jun 2021 11:58:18 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:50189) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lo6mV-0007vW-7x for qemu-devel@nongnu.org; Tue, 01 Jun 2021 11:58:18 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1622563094; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ln7dKDIdS2Ok07dRe0TxA9iBDNDE9dyXN/6L3bb8Xec=; b=dQ0BP2Zp4tz/FYfyYUb165oafGq71iDWyHwr9JegfxcNYIebpC7XQNwtB14CbckHkxF9dR 1tnZkDkBu96yFERFgOcjh4N3zPRKLlYNnZE/CNpn3Q5qrn+IXHKnnuTIiNtpnkkHtu5Nxx KT1Z3rZdtXKXfHdvfC6+lj4AYHrqUdI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-269-3YyEhxl6OOyhFaEevcNU4Q-1; Tue, 01 Jun 2021 11:58:12 -0400 X-MC-Unique: 3YyEhxl6OOyhFaEevcNU4Q-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id ECDEF81840B; Tue, 1 Jun 2021 15:58:10 +0000 (UTC) Received: from localhost (ovpn-113-244.ams2.redhat.com [10.36.113.244]) by smtp.corp.redhat.com (Postfix) with ESMTP id 60D2219C44; Tue, 1 Jun 2021 15:58:04 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [PATCH v2 1/2] vhost-user-blk-test: fix Coverity open(2) false positives Date: Tue, 1 Jun 2021 16:57:54 +0100 Message-Id: <20210601155755.216949-2-stefanha@redhat.com> In-Reply-To: <20210601155755.216949-1-stefanha@redhat.com> References: <20210601155755.216949-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=stefanha@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=216.205.24.124; envelope-from=stefanha@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -13 X-Spam_score: -1.4 X-Spam_bar: - X-Spam_report: (-1.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.371, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, MIME_BASE64_TEXT=1.741, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , Kevin Wolf , Thomas Huth , qemu-block@nongnu.org, Peter Maydell , Coiby Xu , Gerd Hoffmann , Stefan Hajnoczi , Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Coverity checks that the file descriptor return value of open(2) is checked and used. Normally this is helpful in identifying real bugs but vhost-user-blk-test opens /dev/null as stdin and stdout after fork. In this case we don't need to look at the return value because these open(2) calls cannot fail in any reasonable environment. We already know their return values ahead of time since we closed stdin and stdout previously. open(2) is guaranteed to pick the lowest available fd number. Silence Coverity by introducing code that checks what we already know to be true. ** CID 1453270: Resource leaks (RESOURCE_LEAK) /qemu/tests/qtest/vhost-user-blk-test.c: 920 in start_vhost_user_blk() Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Thomas Huth diff --git a/tests/qtest/vhost-user-blk-test.c b/tests/qtest/vhost-user-blk-test.c index 8796c74ca4..c5c4667759 100644 --- a/tests/qtest/vhost-user-blk-test.c +++ b/tests/qtest/vhost-user-blk-test.c @@ -910,14 +910,18 @@ static void start_vhost_user_blk(GString *cmd_line, int vus_instances, storage_daemon_command->str); pid_t pid = fork(); if (pid == 0) { + int fd; + /* * Close standard file descriptors so tap-driver.pl pipe detects when * our parent terminates. */ close(0); + fd = open("/dev/null", O_RDONLY); + g_assert_cmpint(fd, ==, 0); close(1); - open("/dev/null", O_RDONLY); - open("/dev/null", O_WRONLY); + fd = open("/dev/null", O_WRONLY); + g_assert_cmpint(fd, ==, 1); execlp("/bin/sh", "sh", "-c", storage_daemon_command->str, NULL); exit(1);