From nobody Mon Oct 6 17:06:50 2025 Received: from cstnet.cn (smtp81.cstnet.cn [159.226.251.81]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5567033086; Fri, 18 Jul 2025 10:08:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.81 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752833314; cv=none; b=PGnqNniG1qExjxAJQSdh356YrOLYayXbfnz4H2vH9v7uhEvj4VFdGWF0PAJqTmDpDwlhOFIw5ViapboM8Fx4Z01KT+mSYMEtg2hJMSweutHdSmqIngFUD3uwOrOCoU+/kryCS9RrVBm0ovhX5xztvfPb0wvpcGTMCu6KnacCTQM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752833314; c=relaxed/simple; bh=8bt3Uu2z/NA/kSlutCPfVE7KQEvACOpvwhlrZ4sAB/Q=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=mX2q5S4pD3eXzG+hbMe+L/ubzeWNumrx5906N0a28Zc+qywCLuCA29a97rW3jQJA339ngZRV5RcUnfdLmwE5CIk26QIbXuVFjH1QO10kmBGfcoGeLOlBg0E65L9apg5m2lXEzfMR0J3dKvwZc4i7oRqMIp4v6+rqQX85W0Ygql4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.81 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from icess-ProLiant-DL380-Gen10.. (unknown [211.71.28.34]) by APP-03 (Coremail) with SMTP id rQCowAAXrH0QHXpoUwkxBQ--.1396S2; Fri, 18 Jul 2025 18:08:26 +0800 (CST) From: Ma Ke To: eli.billauer@gmail.com, arnd@arndb.de, gregkh@linuxfoundation.org Cc: akpm@linux-foundation.org, linux-kernel@vger.kernel.org, Ma Ke , stable@vger.kernel.org Subject: [PATCH v3] char: xillybus: Fix error handling in xillybus_init_chrdev() Date: Fri, 18 Jul 2025 18:08:15 +0800 Message-Id: <20250718100815.3404437-1-make24@iscas.ac.cn> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: rQCowAAXrH0QHXpoUwkxBQ--.1396S2 X-Coremail-Antispam: 1UD129KBjvJXoW7Ary8Ww1rZw4kur43Wr1xKrg_yoW8Wr18pF 47W3ZYkrW5Ga1jvw1DXa1kCFW3JanFgrZrur47K3sxZwn8ua4xJFW8GrW8XrWUW3yrK3yU tanxAw18JF4xZaDanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9l14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26F4j 6r4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAac4AC62xK8xCEY4vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC 0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr 1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IE rcIFxwCY1x0262kKe7AKxVWUAVWUtwCY02Avz4vE14v_Gw1l42xK82IYc2Ij64vIr41l4I 8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AK xVWUGVWUWwC2zVAF1VAY17CE14v26r126r1DMIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcV AFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r1j6r4UMIIF0xvE42xK8VAvwI8I cIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r 4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfUYxhLUUUUU X-CM-SenderInfo: ppdnvj2u6l2u1dvotugofq/ Content-Type: text/plain; charset="utf-8" Use cdev_del() instead of direct kobject_put() when cdev_add() fails. This aligns with standard kernel practice and maintains consistency within the driver's own error paths. Found by code review. Cc: stable@vger.kernel.org Fixes: 8cb5d216ab33 ("char: xillybus: Move class-related functions to new x= illybus_class.c") Signed-off-by: Ma Ke --- Changes in v3: - modified the patch description, centralized cdev cleanup through standard= API and maintained symmetry with driver's existing error handling; Changes in v2: - modified the patch as suggestions to avoid UAF. --- drivers/char/xillybus/xillybus_class.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/drivers/char/xillybus/xillybus_class.c b/drivers/char/xillybus= /xillybus_class.c index c92a628e389e..e79cf9a0caa4 100644 --- a/drivers/char/xillybus/xillybus_class.c +++ b/drivers/char/xillybus/xillybus_class.c @@ -103,8 +103,7 @@ int xillybus_init_chrdev(struct device *dev, unit->num_nodes); if (rc) { dev_err(dev, "Failed to add cdev.\n"); - /* kobject_put() is normally done by cdev_del() */ - kobject_put(&unit->cdev->kobj); + cdev_del(unit->cdev); goto unregister_chrdev; } =20 @@ -157,8 +156,6 @@ int xillybus_init_chrdev(struct device *dev, device_destroy(&xillybus_class, MKDEV(unit->major, i + unit->lowest_minor)); =20 - cdev_del(unit->cdev); - unregister_chrdev: unregister_chrdev_region(MKDEV(unit->major, unit->lowest_minor), unit->num_nodes); --=20 2.25.1