From patchwork Fri Jul 28 06:58:18 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleksandr Natalenko X-Patchwork-Id: 13331286 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 80DDBC001E0 for ; Fri, 28 Jul 2023 06:59:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233420AbjG1G7L (ORCPT ); Fri, 28 Jul 2023 02:59:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35648 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233354AbjG1G7K (ORCPT ); Fri, 28 Jul 2023 02:59:10 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 185BB1FC8 for ; Thu, 27 Jul 2023 23:58:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1690527506; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Cx8pZcxe7Tol87UHFv5qRe9RKAKvmBBhEVVXZjU3G5s=; b=Zx54brO34sGifwInYvJn6Uj+pz0TjxX6y5K1XlSQSSa5SywrlDGrxcxdcdrGq9lB0WM6pl q0B+LYZo+CJRreGHumEczTcrejW85H35pWuLZ28gdisw23UyFQnXvE2Bke7r5+2QzgxCTx hfY2SiRQp03kp0y5cNTrT071FFKeXRY= Received: from mimecast-mx02.redhat.com (66.187.233.73 [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-442-cL1K542jMgaP8FTszt_LCw-1; Fri, 28 Jul 2023 02:58:22 -0400 X-MC-Unique: cL1K542jMgaP8FTszt_LCw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 1C8791C29AEC; Fri, 28 Jul 2023 06:58:22 +0000 (UTC) Received: from localhost (unknown [10.45.224.187]) by smtp.corp.redhat.com (Postfix) with ESMTP id CCAE94094DC9; Fri, 28 Jul 2023 06:58:21 +0000 (UTC) From: Oleksandr Natalenko To: linux-kernel@vger.kernel.org Cc: linux-scsi@vger.kernel.org, Saurav Kashyap , Johannes Thumshirn , GR-QLogic-Storage-Upstream@marvell.com, "James E.J. Bottomley" , "Martin K. Petersen" , Jozef Bacik , Laurence Oberman , Rob Evers Subject: [PATCH 2/3] scsi: qedf: do not touch __user pointer in qedf_dbg_debug_cmd_read() directly Date: Fri, 28 Jul 2023 08:58:18 +0200 Message-ID: <20230728065819.139694-3-oleksandr@redhat.com> In-Reply-To: <20230728065819.139694-1-oleksandr@redhat.com> References: <20230728065819.139694-1-oleksandr@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org The qedf_dbg_debug_cmd_read() function invokes sprintf() directly on a __user pointer, which may crash the kernel. Avoid doing that by using a small on-stack buffer for sprintf() and then calling simple_read_from_buffer() which does a proper copy_to_user() call. Fixes: 61d8658b4a ("scsi: qedf: Add QLogic FastLinQ offload FCoE driver framework.") Link: https://lore.kernel.org/lkml/20230724120241.40495-1-oleksandr@redhat.com/ Link: https://lore.kernel.org/linux-scsi/20230726101236.11922-1-skashyap@marvell.com/ Cc: Saurav Kashyap Cc: Rob Evers Cc: Johannes Thumshirn Cc: Jozef Bacik Cc: Laurence Oberman Cc: "James E.J. Bottomley" Cc: "Martin K. Petersen" Cc: GR-QLogic-Storage-Upstream@marvell.com Cc: linux-scsi@vger.kernel.org Tested-by: Laurence Oberman Signed-off-by: Oleksandr Natalenko --- drivers/scsi/qedf/qedf_debugfs.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/qedf/qedf_debugfs.c b/drivers/scsi/qedf/qedf_debugfs.c index 4d1b99569d490..f910af0029a2c 100644 --- a/drivers/scsi/qedf/qedf_debugfs.c +++ b/drivers/scsi/qedf/qedf_debugfs.c @@ -138,15 +138,14 @@ qedf_dbg_debug_cmd_read(struct file *filp, char __user *buffer, size_t count, loff_t *ppos) { int cnt; + char cbuf[35]; struct qedf_dbg_ctx *qedf_dbg = (struct qedf_dbg_ctx *)filp->private_data; QEDF_INFO(qedf_dbg, QEDF_LOG_DEBUGFS, "debug mask=0x%x\n", qedf_debug); - cnt = sprintf(buffer, "debug mask = 0x%x\n", qedf_debug); + cnt = sprintf(cbuf, "debug mask = 0x%x\n", qedf_debug); - cnt = min_t(int, count, cnt - *ppos); - *ppos += cnt; - return cnt; + return simple_read_from_buffer(buffer, count, ppos, cbuf, cnt); } static ssize_t