From patchwork Thu Jul 21 02:15:54 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qiang Yu X-Patchwork-Id: 592516 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 224D6C433EF for ; Thu, 21 Jul 2022 02:16:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229724AbiGUCQZ (ORCPT ); Wed, 20 Jul 2022 22:16:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35112 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229515AbiGUCQY (ORCPT ); Wed, 20 Jul 2022 22:16:24 -0400 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E355A6BC0F; Wed, 20 Jul 2022 19:16:23 -0700 (PDT) Received: from pps.filterd (m0279872.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 26L1ROW0004847; Thu, 21 Jul 2022 02:16:13 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : mime-version : content-type; s=qcppdkim1; bh=M2M6I18ySNIp/h+Xnf4yxDrn7dqGutjGEaAxUEh70IA=; b=beuqUz3Nt82I3GVAflSX8ZcRUU6rIOlvaAVLUORkI7eAl4qicvBep2xrNgJE0JM+8MIN TJ6z5LgePeCUon7y8DbUZHg/TnHlRn47GmS6Bf9o3JYs76nXmDmMDNFegH2iC/nh3Guw yF0LkORlD6dNOPl+vYzvUTbL0OOS6L+9RDgdgxEgO20XTCe1VR2BzQXsCaQ4zY28wHWZ BXWXhUEfq/sbqI20TUeoocpRSQiLCV7cfrJuE6EUzehH1RuSk8aD4Ya5Jo26vPDuILK3 yHbOqEwRtstLOYPNMdVhHJLrzAjoVy+aa81GOlsasnUB1Fc6JpfDVhtpodThSSyzJoL4 yw== Received: from nasanppmta01.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3heb3x2q3a-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 21 Jul 2022 02:16:13 +0000 Received: from nasanex01a.na.qualcomm.com ([10.52.223.231]) by NASANPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 26L2GC6W028633 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 21 Jul 2022 02:16:12 GMT Received: from cbsp-sh-gv.qualcomm.com (10.80.80.8) by nasanex01a.na.qualcomm.com (10.52.223.231) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.22; Wed, 20 Jul 2022 19:16:10 -0700 From: Qiang Yu To: , , , CC: , , , , Qiang Yu Subject: [PATCH v2 1/1] bus: mhi: host: Fix up null pointer access in mhi_irq_handler Date: Thu, 21 Jul 2022 10:15:54 +0800 Message-ID: <1658369754-87005-1-git-send-email-quic_qianyu@quicinc.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nasanex01a.na.qualcomm.com (10.52.223.231) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: WEODm89xukhm_cKTR4Rwb_ojT38sPDa_ X-Proofpoint-ORIG-GUID: WEODm89xukhm_cKTR4Rwb_ojT38sPDa_ X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-07-20_12,2022-07-20_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 mlxlogscore=954 impostorscore=0 spamscore=0 clxscore=1015 suspectscore=0 bulkscore=0 mlxscore=0 phishscore=0 lowpriorityscore=0 adultscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2206140000 definitions=main-2207210009 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The irq handler for a shared IRQ ought to be prepared for running even now it's being freed. So let's check the pointer used by mhi_irq_handler to avoid null pointer access since it is probably released before freeing IRQ. Signed-off-by: Qiang Yu --- v1->v2: change dev_err to dev_dbg drivers/bus/mhi/host/main.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/drivers/bus/mhi/host/main.c b/drivers/bus/mhi/host/main.c index f3aef77a..25ea1f8 100644 --- a/drivers/bus/mhi/host/main.c +++ b/drivers/bus/mhi/host/main.c @@ -430,12 +430,20 @@ irqreturn_t mhi_irq_handler(int irq_number, void *dev) { struct mhi_event *mhi_event = dev; struct mhi_controller *mhi_cntrl = mhi_event->mhi_cntrl; - struct mhi_event_ctxt *er_ctxt = - &mhi_cntrl->mhi_ctxt->er_ctxt[mhi_event->er_index]; + struct mhi_event_ctxt *er_ctxt; struct mhi_ring *ev_ring = &mhi_event->ring; - dma_addr_t ptr = le64_to_cpu(er_ctxt->rp); + dma_addr_t ptr; void *dev_rp; + if (!mhi_cntrl->mhi_ctxt) { + dev_dbg(&mhi_cntrl->mhi_dev->dev, + "mhi_ctxt has been freed\n"); + return IRQ_HANDLED; + } + + er_ctxt = &mhi_cntrl->mhi_ctxt->er_ctxt[mhi_event->er_index]; + ptr = le64_to_cpu(er_ctxt->rp); + if (!is_valid_ring_ptr(ev_ring, ptr)) { dev_err(&mhi_cntrl->mhi_dev->dev, "Event ring rp points outside of the event ring\n");