From nobody Fri Oct 2 10:09:54 2026 Received: from mailgw.kylinos.cn (mailgw.kylinos.cn [124.126.103.232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E6C9830676A for ; Mon, 3 Aug 2026 01:55:00 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=124.126.103.232 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785722103; cv=none; b=SvT2Gdp5XhIhvDZZAa7a//iemrbyrUArOaOe3w9+X16LMlQ+hDZPVOf1YNyj50rfD6xy7QZm8/+Sukg/jP/ocVQmrO9ofZiyTnMZPLFgMDzzee/yOeiDFGIu3JwmsPhVgQNDEUJF7pwzSfBneOtB24H3dJUT/DEHJPWc5pnbLu4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785722103; c=relaxed/simple; bh=YLjIfQL9K2Hc0QNg/+ORie4Pr7PgfqbI4CnFZnMw4uU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=Wt2lv2EIZudIdaed0B8tbZDgFp8Z9uLa1gSjgHmSEKDNFcZuMfLNDMJH/dGo5YexKEc2qiRp4Ih1PQzbFYqrl2VP2fZpLXrptwTPhp87B4SeRRYfd+Y6Nh5INZEckKTp7vmXmboqDLbWGkhbtjGwQdOyS9lNA/+UMRYbgfbT5nU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn; spf=pass smtp.mailfrom=kylinos.cn; arc=none smtp.client-ip=124.126.103.232 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=kylinos.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=kylinos.cn X-UUID: 53ad37588ede11f1aa26b74ffac11d73-20260803 X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.3.12,REQID:38449792-9b1a-47a8-8a6f-ecc22b0b6b6e,IP:0,U RL:0,TC:0,Content:-5,EDM:0,RT:0,SF:0,FILE:0,BULK:0,RULE:Release_Ham,ACTION :release,TS:-5 X-CID-META: VersionHash:e7bac3a,CLOUDID:290ba0852b22f094bac7e47af176a247,BulkI D:nil,BulkQuantity:0,Recheck:0,SF:81|82|102|850|865|898,TC:nil,Content:0|1 5|50,EDM:-3,IP:nil,URL:0,File:nil,RT:nil,Bulk:nil,QS:nil,BEC:nil,COL:0,OSI :0,OSA:0,AV:0,LES:1,SPR:NO,DKR:0,DKP:0,BRR:0,BRE:0,ARC:0 X-CID-BVR: 2,SSN|SDN X-CID-BAS: 2,SSN|SDN,0,_ X-CID-FACTOR: TF_CID_SPAM_SNR X-CID-RHF: D41D8CD98F00B204E9800998ECF8427E X-UUID: 53ad37588ede11f1aa26b74ffac11d73-20260803 X-User: gonglinkai@kylinos.cn Received: from localhost.localdomain [(10.44.16.150)] by mailgw.kylinos.cn (envelope-from ) (Generic MTA with TLSv1.3 TLS_AES_256_GCM_SHA384 256/256) with ESMTP id 1770409549; Mon, 03 Aug 2026 09:54:56 +0800 From: Linkai Gong To: Jim Cromie , Arnd Bergmann , Greg Kroah-Hartman Cc: Andrew Morton , linux-kernel@vger.kernel.org, Linkai Gong Subject: [PATCH v2] char: scx200_gpio: check cdev_add() return value Date: Mon, 3 Aug 2026 09:54:50 +0800 Message-Id: <20260803015450.2050900-1-gonglinkai@kylinos.cn> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20260730095321.2386744-1-gonglinkai@kylinos.cn> References: <20260730095321.2386744-1-gonglinkai@kylinos.cn> 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 Content-Type: text/plain; charset="utf-8" cdev_add() can fail. The driver currently ignores the return value and reports probe success even when the cdev was not registered, leaving a chrdev region allocated with no working file operations. Check the return value, emit an error, and unwind the chrdev region and platform device on failure. Fixes: 635adb6cd25c ("[PATCH] scx200_gpio: use 1 cdev for N minors, not N f= or N") Signed-off-by: Linkai Gong --- v2: - Use "if (rc)" instead of "if (rc < 0)" as suggested by Greg drivers/char/scx200_gpio.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/char/scx200_gpio.c b/drivers/char/scx200_gpio.c index 700e6affea6f..3ec17832e9c9 100644 --- a/drivers/char/scx200_gpio.c +++ b/drivers/char/scx200_gpio.c @@ -107,10 +107,16 @@ static int __init scx200_gpio_init(void) } =20 cdev_init(&scx200_gpio_cdev, &scx200_gpio_fileops); - cdev_add(&scx200_gpio_cdev, devid, MAX_PINS); + rc =3D cdev_add(&scx200_gpio_cdev, devid, MAX_PINS); + if (rc) { + dev_err(&pdev->dev, "cdev_add err: %d\n", rc); + goto undo_chrdev_region; + } =20 return 0; /* succeed */ =20 +undo_chrdev_region: + unregister_chrdev_region(devid, MAX_PINS); undo_platform_device_add: platform_device_del(pdev); undo_malloc: --=20 2.25.1