From nobody Wed Feb 11 19:41:34 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 792CBCA0EC3 for ; Mon, 11 Sep 2023 23:26:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235202AbjIKXVW (ORCPT ); Mon, 11 Sep 2023 19:21:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57478 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233206AbjIKWr4 (ORCPT ); Mon, 11 Sep 2023 18:47:56 -0400 Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B137A9D95A for ; Mon, 11 Sep 2023 15:39:49 -0700 (PDT) Received: from pps.filterd (m0356517.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 38BMaJEE006031; Mon, 11 Sep 2023 22:38:15 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ibm.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=pp1; bh=1Fld4uLHCkOxTnE+D78lng+nsIUaKvsf31r8U2qQ7oU=; b=hJVkJzmGbc4Sy6WxCa+ryJ9efkfHYbQ1vFWQoLBy9htpksbwDGeFm6yOyumAU7IkpeFt N/6B9n90DAVHDvi1MgarXOwFiE6MWC2sb+teV+itc3ok4JN6CO4/35ZOe5pwGwyVnQ67 1LWkucYBrGLfH6tgL8pUpBTV9/E3bNtvz36q2dVwDfFgaDb0ywe59Ul5hgs/DNLDiAls cX/6gKg0E+HrFCeZb7KBryhYJBR0bRYsQV9BQ+Hvgm3+dJ+1CM89XoIZZJtKqh5knuyF puI8SsrCn3FK8WL+b5rxGrzYLfzx/zwdVRC9Kedt//YHDLeYk40EaAmlO/jdkpocAAZx hw== Received: from ppma23.wdc07v.mail.ibm.com (5d.69.3da9.ip4.static.sl-reverse.com [169.61.105.93]) by mx0a-001b2d01.pphosted.com (PPS) with ESMTPS id 3t2b6frt60-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 11 Sep 2023 22:38:15 +0000 Received: from pps.filterd (ppma23.wdc07v.mail.ibm.com [127.0.0.1]) by ppma23.wdc07v.mail.ibm.com (8.17.1.19/8.17.1.19) with ESMTP id 38BM0aUc002967; Mon, 11 Sep 2023 22:38:13 GMT Received: from smtprelay06.wdc07v.mail.ibm.com ([172.16.1.73]) by ppma23.wdc07v.mail.ibm.com (PPS) with ESMTPS id 3t14hkp4y0-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 11 Sep 2023 22:38:13 +0000 Received: from smtpav05.dal12v.mail.ibm.com (smtpav05.dal12v.mail.ibm.com [10.241.53.104]) by smtprelay06.wdc07v.mail.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 38BMcCpt66322748 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 11 Sep 2023 22:38:13 GMT Received: from smtpav05.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id BAB1B58071; Mon, 11 Sep 2023 22:38:12 +0000 (GMT) Received: from smtpav05.dal12v.mail.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 700145806F; Mon, 11 Sep 2023 22:38:12 +0000 (GMT) Received: from gfwa153.aus.stglabs.ibm.com (unknown [9.3.84.127]) by smtpav05.dal12v.mail.ibm.com (Postfix) with ESMTP; Mon, 11 Sep 2023 22:38:12 +0000 (GMT) From: Ninad Palsule To: jk@ozlabs.org, joel@jms.id.au, alistair@popple.id.au, eajames@linux.ibm.com, linux-fsi@lists.ozlabs.org, linux-kernel@vger.kernel.org Cc: Ninad Palsule Subject: [PATCH v2 2/2] fsi: sbefifo: Validate pending user write Date: Mon, 11 Sep 2023 17:38:09 -0500 Message-Id: <20230911223809.3505431-3-ninad@linux.ibm.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230911223809.3505431-1-ninad@linux.ibm.com> References: <20230911223809.3505431-1-ninad@linux.ibm.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-TM-AS-GCONF: 00 X-Proofpoint-GUID: tVY6PrFELdtuVnJMlhwFlSVmLvr5WIst X-Proofpoint-ORIG-GUID: tVY6PrFELdtuVnJMlhwFlSVmLvr5WIst X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.957,Hydra:6.0.601,FMLib:17.11.176.26 definitions=2023-09-11_18,2023-09-05_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 clxscore=1015 impostorscore=0 bulkscore=0 mlxscore=0 adultscore=0 mlxlogscore=999 malwarescore=0 priorityscore=1501 suspectscore=0 spamscore=0 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2308100000 definitions=main-2309110207 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" This commit rejects user write operation if previous write operation is still pending. As per the current kernel driver design, write operation prepares a buffer for FSI write, the actual FSI write is performed on next read operation. There is a possibility of memory leak if buggy application sends two back to back writes or two parallel writes. Signed-off-by: Ninad Palsule --- drivers/fsi/fsi-sbefifo.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/fsi/fsi-sbefifo.c b/drivers/fsi/fsi-sbefifo.c index a95b32461f8f..fc41cdd6e890 100644 --- a/drivers/fsi/fsi-sbefifo.c +++ b/drivers/fsi/fsi-sbefifo.c @@ -877,6 +877,12 @@ static ssize_t sbefifo_user_write(struct file *file, c= onst char __user *buf, =20 mutex_lock(&user->file_lock); =20 + /* Previous write is still in progress */ + if (user->pending_cmd) { + mutex_unlock(&user->file_lock); + return -EALREADY; + } + /* Can we use the pre-allocate buffer ? If not, allocate */ if (len <=3D PAGE_SIZE) user->pending_cmd =3D user->cmd_page; --=20 2.39.2