From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from OSPPR02CU001.outbound.protection.outlook.com (mail-norwayeastazon11013065.outbound.protection.outlook.com [40.107.159.65]) (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 AE07D2D3A93; Sun, 4 Oct 2026 01:03:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.159.65 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791075808; cv=fail; b=ALCcQewS9H9k09Td83Z1jW3XFZGcwoJV+XZFgTBkEk/rXXzgyrqlIU9M4aionfMDWu5/J3gMKa7KE5rzu/jHiAvtK9RRta3lKGufITbONqfF8JX1l1PPPBDSTqcHm1MjCfEIyo+3k37fW/lX4XKR6O9oFzWYwXF0D53BPuZDZDE= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791075808; c=relaxed/simple; bh=Z61xYa8Li1dZTN0PIWWF/VsRo45bH6SI7IWjVFlO9l8=; h=Date:From:To:Cc:Subject:Message-ID:References:Content-Type: Content-Disposition:In-Reply-To:MIME-Version; b=MbWR+Yon4Nr/QD0u7yjW26m2BOMOZlP8ubPgmMxF8WS1XRvCcRupGCFPe4uiRSY+wd/5kbxflX+b19DXYCmM9MB5RFr/AbcSXuUKR3nJzkvJisaOVb6ciSq/N3ZB7BZd15ro5S+7MXKV1NEv/XnmZsDOqdjaqPCmcqSVZhtbSYw= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=oss.nxp.com; spf=pass smtp.mailfrom=oss.nxp.com; dkim=pass (2048-bit key) header.d=NXP1.onmicrosoft.com header.i=@NXP1.onmicrosoft.com header.b=n2w7gsx3; arc=fail smtp.client-ip=40.107.159.65 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=oss.nxp.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oss.nxp.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=NXP1.onmicrosoft.com header.i=@NXP1.onmicrosoft.com header.b="n2w7gsx3" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=iqBqeRqaN7+oMIvaVWfenoydnZAInASR/HG5+24vAFImNWyhRURwVakN8bTDsrL/uVYYK8Cq0r8tj973N9hVanwWEFP97OLywZKup2KduroMRBI+VAUJrButonB0taTEOcubdFEPpfCE1Cqr19YtAEBFRGKs4jpOFc0mkYtMGvGBWlEfwbzoFGIPiJL/8xUQIRuVJ8akpaD/nJgZ160kJbhdv6K6DeyPo+r+/U4vzmgboGooKjxQIcWHzeWqACP9B6go1RiAzkUmB2QY1xGaWqMqLcmG/ru/qmGogoTs1AYYjxwRo4eS/9t21GBVZ4rLR6oBO80T97Uu1m+SmvMpAQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=8ISXExPHFCSOvtnoAH8xjnQkXFKIakDJBDEhh7piGY8=; b=ify8XGADW2/jurpC8/0fBlMePgkYA38yvNHF2fFHbQZl/jmSPkA05AMmw7ye4UQLw9iwWqRB1E62JANlZcr+En9ybQdugYJ1ZgppO+thpIxus+lMNVd9wBvRWWV2d0rRBzoHRe+9J10ITSo8A2a1Ra625+F4cdeED8SgKuYYfRkl1IL9Oy0lqrUqG1bxIEB2lQr4Ad/+FNNo8NVxcQNKoHUAQ1p1kXX8lLcXSVoycbVySVw1pVJFaAhqgdEVqpCckBKDQ8OXNptuFQYmc94pB7AHtTbgV4IcM9MlomdDsBQnrvtL3RGU43fPuXfUE2RIK24xr0bT8KXIxcEyLZ3d+Q== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oss.nxp.com; dmarc=pass action=none header.from=oss.nxp.com; dkim=pass header.d=oss.nxp.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=NXP1.onmicrosoft.com; s=selector1-NXP1-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=8ISXExPHFCSOvtnoAH8xjnQkXFKIakDJBDEhh7piGY8=; b=n2w7gsx3G8NZyCkR5G0hM3Ak68ddOuI+u0CnrmGJ4siUNPXwJf+w79U/I5DogvL2fZo2bu4Cevz5sODiLHILst25fgkZIyR6MC351vmTepSCyCS4Ik5GI5Wdc9mnxwaKlldB5eZxj39ZszyEqBNrNJGxedk9hpvAdPlAqIcoad5d0uKw/wyGe3jzCFMk7VZ3fzw6bsBtDzgtL3hxIfeMPPSalJkU0rrSSFqUBfqEMm0ffyOZyATMuCntj9WJxZBzzakiT5HEyD2Ex4ibs8Er735Nqbm3nKhVrZWCnIoSR/DKWbAT4FIl09PgrQblkPctWR5zcS2p35ne/20LdCT8ww== Authentication-Results: mx.microsoft.com 1; dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=oss.nxp.com; Received: from GV2PR04MB11799.eurprd04.prod.outlook.com (2603:10a6:150:2cf::9) by VI1PR04MB7104.eurprd04.prod.outlook.com (2603:10a6:800:126::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.21.472.20; Sun, 4 Oct 2026 01:03:22 +0000 Received: from GV2PR04MB11799.eurprd04.prod.outlook.com ([fe80::2146:83a2:5329:b7c]) by GV2PR04MB11799.eurprd04.prod.outlook.com ([fe80::2146:83a2:5329:b7c%7]) with mapi id 15.21.0472.016; Sun, 4 Oct 2026 01:03:22 +0000 Date: Sat, 3 Oct 2026 20:03:13 -0500 From: Frank Li To: Jiale Yao Cc: Laurent Pinchart , Vinod Koul , Frank Li , Michal Simek , Hyun Kwon , dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] dmaengine: xilinx: dpdma: Reserve space for a string terminator Message-ID: References: <20261003095922.575350-1-yaojiale02@163.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261003095922.575350-1-yaojiale02@163.com> X-ClientProxiedBy: PH2PEPF00003847.namprd17.prod.outlook.com (2603:10b6:518:1::64) To GV2PR04MB11799.eurprd04.prod.outlook.com (2603:10a6:150:2cf::9) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: GV2PR04MB11799:EE_|VI1PR04MB7104:EE_ X-MS-Office365-Filtering-Correlation-Id: e6825292-5525-43bd-0aaf-08df21b34913 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|376014|19092799006|23010399003|11063799006|5023799004|56012099006|10067099003|22082099003|18002099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:GV2PR04MB11799.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(1800799024)(376014)(19092799006)(23010399003)(11063799006)(5023799004)(56012099006)(10067099003)(22082099003)(18002099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?209kUqezx2zzuhl3ZA2lXqtR8IfVoHWdrsVB/G1Kafj4APmYYnTdIAV4NiZd?= =?us-ascii?Q?nV4mk2RSVisb0bTcJHPUBIWMibSf3f3T7L25WFEYSx1kj0QWITJ/bFXUp4ue?= =?us-ascii?Q?7xaYVv3fRBL1J3z9ZDp6yHGf+WyafBvutRvykAqkqc+CCL4+ekseMpG1g/Pi?= =?us-ascii?Q?lNLxVNbTpI1HsnRRatSc4NYVl52xCrygeTlB7RHRocOCl5wDOMtSvzQ2EQb+?= =?us-ascii?Q?1HhTjBpCDlHtkB7QdzaZl7EM0ShXbxrMJAaJ1ZKMZ27tRu212jHX/7v2kG/l?= =?us-ascii?Q?lxbX8hs3vSoDn2cSuaGGcL8ms3hMxcoOVLo5WsiJS96l3x5B6poDYmzfNe/d?= =?us-ascii?Q?UDLRD8eZoSenH1WRvqeWF27pYkDBUnQh/okxbNwW9bkm34ByDvkQSgbKD5RF?= =?us-ascii?Q?ErN5ljSN1nEFX8nd7kGcxTNxAGIqCxHxDfWYnWjFTmYGqVYugKlO3mNhsSLa?= =?us-ascii?Q?CycSdAEwJ95Gn+kZgAC3wieCsyxMAGfkPl9lIFZQVKu5fFA3Fp4rd0DBShWZ?= =?us-ascii?Q?dBxaPI53VMNoazV/YpHmooR5n3ac+3JM1RDWE5Db1tD76Fjk0ngudY108dpv?= =?us-ascii?Q?sFhVhewH1RPz560qLI26xGvRfAVE98bS+Baau6bKG6jVQ2LXwhskQaZrr6Bj?= =?us-ascii?Q?tx+UGXUBQH5FXEAnsLcIeRyS8Yw2l14uVDBJ+Pg62DPNCdecfEooiQal+Qsn?= =?us-ascii?Q?8vzCar2IncHjQf7Dr+n6CxvnXHY2vs8fdTFjBDFhyUaHjeiafnitwmB+r5TU?= =?us-ascii?Q?+az8Bcn8tw7RSOzgVT+MwkgxVTsldQ4zlqsjR+RKAM7SzxngCAWOb0i5fASw?= =?us-ascii?Q?kKOB19FcoJIPQzNygm6PB0qNU7NI83UFv4DatIQAOpMT4OreKr+cOW7WUnM+?= =?us-ascii?Q?6tTgF9GpwlMxcn0lDhHCrz+QyiJoKVwLspuNAu3h6Etvra9cjBeUdogrZLCT?= =?us-ascii?Q?EJnQ0rf0O5cd/glH0ucTheBPNWxwzEvMzyqxNvIRA8TSPaVFVA+V52mW1T+k?= =?us-ascii?Q?/fvOilkKQlagqF801hEqsH4jY1Vd7XKcb1+7RPiaj4Hl9wqtJaRHRdv9zdYk?= =?us-ascii?Q?Ge/eUPupqzeC5ySjp2Mk8UTPTgC/qWygoWHqxfOCpcxFVcz83TyVXZiex06Z?= =?us-ascii?Q?Zbdj1h1wOrdR7WsRH4OcDHYdZ5heTIlxVtTd4HUmJvyyu/7vfs49Ieb0wiA7?= =?us-ascii?Q?GVsEOtCrhRqn4aqPVSIGdWsBhpGHisybJMuDMhhJnHnwHeacTaJc2bECyCWo?= =?us-ascii?Q?u0Y4mbMB55difadklhHOqa66GNyhb9hn1o7MRGoJkBcr+dg817nypdk8MwiV?= =?us-ascii?Q?BRrTeOaZM1ZN9haNAem7Tg6APl7CxtnrbwutQZhW/WXFczANglBkGDXbjXu7?= =?us-ascii?Q?poJqytLJbctXGuAOgNT5CTRohk4Lz+H7uSZP5QZ9RHte9qWb45AJbnUo3rIT?= =?us-ascii?Q?iLuIsB1y07vr4s0Y0A5zCsNrACr8xdWWVZoE2etniiXJtAGxJhVlk9fQohF7?= =?us-ascii?Q?hDg1qiZJ6bgQB0qqVHIQajKreXNoHQSY9UF61EbKUelioPVykcGsYBCdsTy0?= =?us-ascii?Q?IVw4CjjvrMFNDOEc6jYXX02b9WMXGck2r0pFRE+3l0ZBWMF7+igkHnzAZakz?= =?us-ascii?Q?Z+bDLPx8SjdSb1pmMonUy5EL8o+M/W/pi1d/eQI8c3K3Q0tmN2ca1fvD0si/?= =?us-ascii?Q?fAa3iQ34zlnOKZANRH3tIWXNNh1sBJ0agneTQQ+qRSAshOK5Bc6KFPlXPSfa?= =?us-ascii?Q?7y1LSPP0nP23v4K0SG2TfujFU1ShP8XYbVOMiS2hnFMlILf7YwDc?= X-OriginatorOrg: oss.nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: e6825292-5525-43bd-0aaf-08df21b34913 X-MS-Exchange-CrossTenant-AuthSource: GV2PR04MB11799.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Oct 2026 01:03:22.1771 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: AaIOYItwyyzumhbCl1vZ5652gc9y4AiTP9qWxUyvxkPCWBONXcn3NS9CrvfAFOTiKSIuqt98WIx3JO8ICPJ3u1/5EaNhrMIFTbEMQvheBiBpBCNzmVh5jLBlLOGv4pnr X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB7104 On Sat, Oct 03, 2026 at 05:59:22PM +0800, Jiale Yao wrote: > xilinx_dpdma_debugfs_write() copies size bytes from userspace and parses > them with strsep() and strcasecmp(). If the input has no NUL within that > range, the parser can read beyond the allocation. > > Use memdup_user_nul() to copy the complete input and append a terminating > NUL. > > Fixes: 1d220435cab3 ("dmaengine: xilinx: dpdma: Add debugfs support") > Signed-off-by: Jiale Yao > > --- Reviewed-by: Frank Li > > Changes in v2: > - Replace kzalloc() and strncpy_from_user() with memdup_user_nul(), as > suggested by Laurent. > > diff --git a/drivers/dma/xilinx/xilinx_dpdma.c b/drivers/dma/xilinx/xilinx_dpdma.c > index d9a3542c4531..219d25be6c3a 100644 > --- a/drivers/dma/xilinx/xilinx_dpdma.c > +++ b/drivers/dma/xilinx/xilinx_dpdma.c > @@ -410,15 +410,11 @@ static ssize_t xilinx_dpdma_debugfs_write(struct file *f, > if (dpdma_debugfs.testcase != DPDMA_TC_NONE) > return -EBUSY; > > - kern_buff = kzalloc(size, GFP_KERNEL); > - if (!kern_buff) > - return -ENOMEM; > + kern_buff = memdup_user_nul(buf, size); > + if (IS_ERR(kern_buff)) > + return PTR_ERR(kern_buff); > kern_buff_start = kern_buff; > > - ret = strncpy_from_user(kern_buff, buf, size); > - if (ret < 0) > - goto done; > - > /* Read the testcase name from a user request. */ > testcase = strsep(&kern_buff, " "); > > -- > 2.34.1 >