From patchwork Mon Feb 10 12:10:45 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= X-Patchwork-Id: 13967781 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.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 smtp.lore.kernel.org (Postfix) with ESMTPS id 78C01C02198 for ; Mon, 10 Feb 2025 12:11:46 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1thScw-0006M2-5h; Mon, 10 Feb 2025 07:11:02 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1thScp-0006KL-6o for qemu-devel@nongnu.org; Mon, 10 Feb 2025 07:10:58 -0500 Received: from mail-wr1-x434.google.com ([2a00:1450:4864:20::434]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1thScn-00032G-F8 for qemu-devel@nongnu.org; Mon, 10 Feb 2025 07:10:54 -0500 Received: by mail-wr1-x434.google.com with SMTP id ffacd0b85a97d-38dcb33cba1so1450526f8f.2 for ; Mon, 10 Feb 2025 04:10:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1739189447; x=1739794247; darn=nongnu.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=tz6g0+yjWCc5q957kaMmUJ2SDM1V5eBl57QBVioAIgI=; b=rsrbqxL5olTPLrZ8xU5wUYXubCNXcRzDEl8QBKvln43G86gDOXqI8M0M9YtHdZYfBX lLfH/S/un1xF9zLiMKILZykGIl+CpjQCDsmpCGdWui8P0UCVJ8zQRbr4Ef294xBHY+WK XtZms29+V3FlNIlfbDCmdbhifNj8AREQ8f8SkGtCqQLIOM2R3+trjDoOiOy9z+6kKLE5 tQs38A6NcQkUJDtbgSJI/ra/Mayms5Z/hRyOPXEnUEsHOPmrytGVh0jGWV5agaCvOzry PQ2uC6z7ozJqUh4AsmcSWZpWfhhMt/A/K9gX2st1smf2h4E4Y2ix/67U1wJqoouV/iSk fvmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1739189447; x=1739794247; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=tz6g0+yjWCc5q957kaMmUJ2SDM1V5eBl57QBVioAIgI=; b=kGiOce9v8dB2/iucZcbWn0rGH5L2WkCG5ne4Svrx3nWJEeNuCOBH6NAQYC11seYdQ0 yA2kNOYItIALT9LQQDMpGkUxxaDqKYOwQYNlC9DSNSWWIE02gkGWJREm5ALagQY5wibf fNxVR5hihuAWLuwxSTub00IBnSBvsJG3kjgEZj5d1pcwJ77hp4XU8Jrn33/MI0u7pqS0 lsgaAyPoPb4UPZTllLYPeydOheOsM5MciocVzCxWPq9uu2xBdijxYeC0zpK7Voli9fFy Ip+oFFLP1xvM8Cgvr6iANp+j4KtObRWE/uStzGULETtYzYX/7/mL11PGVRLDcyeQnhzz ZfCw== X-Gm-Message-State: AOJu0YxCBgNy7NaHFxiD48l55/e/Pb+QX2L2l9kv3KxDFGAd2EjQWKPm LS4AvowNaSn0pTcDy3vSZLaZsqmBMUjCw5McPFDU3Qf/HyfVpU1ZiGZ4UIvqijUUtKtpdTNYZPT wOyc= X-Gm-Gg: ASbGncun3hHNcAcwWdGdsYJ646f7uRFY5TP8+mfQvVpTCIDGy7uc3d0QnPNkY8+syz2 TDf07Cu1P7gI2XuWzNg7mz/35gzZZ1FfrJw1ucwYmgSbS9YfOSSw5/1NojzDEOpKFVNKKx4883K TkefRP191tolSLr7scJ30fz6H4eOUFt30UklFADo0cnfhPc8U2tu36tD2w3w5W93VaFOxqVydJJ s0XGJU9fUGUI20eYQbj5N3iLjCv8kUYDk+ReplQ1dVNHqJRdaebsMPjIk9ipu72yd8olX3XY5OG uBMYqKtI45kPmFB2t/TfE6AXPkXWP+M1oi47nZDOIpMxi41WapyJBkGxk7L9AOkTQek6ai8= X-Google-Smtp-Source: AGHT+IFyIq98wfL8aNbGeiF2nCLbaI1dam8txKqn9eh80P51r6lKT2qqMWcbpETpB7iIMMF6jPngpw== X-Received: by 2002:a05:6000:1865:b0:386:1cd3:8a03 with SMTP id ffacd0b85a97d-38dc9346494mr9790567f8f.32.1739189447488; Mon, 10 Feb 2025 04:10:47 -0800 (PST) Received: from localhost.localdomain (88-187-86-199.subs.proxad.net. [88.187.86.199]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4390d93369fsm180642855e9.3.2025.02.10.04.10.46 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Mon, 10 Feb 2025 04:10:47 -0800 (PST) From: =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= To: qemu-devel@nongnu.org Cc: Paolo Bonzini , Jens Freimann , Eduardo Habkost , =?utf-8?q?Daniel_P=2E_Berrang=C3=A9?= , =?utf-8?q?Phil?= =?utf-8?q?ippe_Mathieu-Daud=C3=A9?= , Peter Maydell Subject: [PATCH] system/qdev: Remove pointless NULL check in qdev_device_add_from_qdict Date: Mon, 10 Feb 2025 13:10:45 +0100 Message-ID: <20250210121045.38908-1-philmd@linaro.org> X-Mailer: git-send-email 2.47.1 MIME-Version: 1.0 Received-SPF: pass client-ip=2a00:1450:4864:20::434; envelope-from=philmd@linaro.org; helo=mail-wr1-x434.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Coverity reported a unnecessary NULL check: qemu/system/qdev-monitor.c: 720 in qdev_device_add_from_qdict() 683 /* create device */ 684 dev = qdev_new(driver); ... 719 err_del_dev: >>> CID 1590192: Null pointer dereferences (REVERSE_INULL) >>> Null-checking "dev" suggests that it may be null, but it has already been dereferenced on all paths leading to the check. 720 if (dev) { 721 object_unparent(OBJECT(dev)); 722 object_unref(OBJECT(dev)); 723 } 724 return NULL; 725 } Indeed, unlike qdev_try_new() which can return NULL, qdev_new() always returns a heap pointer (or aborts). Remove the unnecessary assignment and check. Fixes: f3a85056569 ("qdev/qbus: add hidden device support") Resolves: Coverity CID 1590192 (Null pointer dereferences) Suggested-by: Peter Maydell Signed-off-by: Philippe Mathieu-Daudé Reviewed-by: Richard Henderson --- system/qdev-monitor.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/system/qdev-monitor.c b/system/qdev-monitor.c index 861c25c855f..01d4b007322 100644 --- a/system/qdev-monitor.c +++ b/system/qdev-monitor.c @@ -628,7 +628,7 @@ DeviceState *qdev_device_add_from_qdict(const QDict *opts, DeviceClass *dc; const char *driver, *path; char *id; - DeviceState *dev = NULL; + DeviceState *dev; BusState *bus = NULL; QDict *properties; @@ -717,10 +717,9 @@ DeviceState *qdev_device_add_from_qdict(const QDict *opts, return dev; err_del_dev: - if (dev) { - object_unparent(OBJECT(dev)); - object_unref(OBJECT(dev)); - } + object_unparent(OBJECT(dev)); + object_unref(OBJECT(dev)); + return NULL; }