From patchwork Tue Sep 20 17:05:32 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Roth X-Patchwork-Id: 672387 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3sdqdP6CCMz9sBX for ; Wed, 21 Sep 2016 03:34:49 +1000 (AEST) Received: from localhost ([::1]:36991 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bmOwR-0005Vw-GR for incoming@patchwork.ozlabs.org; Tue, 20 Sep 2016 13:34:47 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43296) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bmOUq-0007NN-29 for qemu-devel@nongnu.org; Tue, 20 Sep 2016 13:06:20 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bmOUm-0007RS-7P for qemu-devel@nongnu.org; Tue, 20 Sep 2016 13:06:14 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:50119) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bmOUl-0007Pp-Tf for qemu-devel@nongnu.org; Tue, 20 Sep 2016 13:06:12 -0400 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u8KH3YiM054795 for ; Tue, 20 Sep 2016 13:06:11 -0400 Received: from e38.co.us.ibm.com (e38.co.us.ibm.com [32.97.110.159]) by mx0a-001b2d01.pphosted.com with ESMTP id 25k7bhwpuv-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 20 Sep 2016 13:06:11 -0400 Received: from localhost by e38.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 20 Sep 2016 11:06:06 -0600 Received: from b03cxnp08025.gho.boulder.ibm.com (b03cxnp08025.gho.boulder.ibm.com [9.17.130.17]) by d03dlp01.boulder.ibm.com (Postfix) with ESMTP id 9979C1FF004B; Tue, 20 Sep 2016 11:05:47 -0600 (MDT) Received: from b03ledav003.gho.boulder.ibm.com (b03ledav003.gho.boulder.ibm.com [9.17.130.234]) by b03cxnp08025.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u8KH66Km13107516; Tue, 20 Sep 2016 10:06:06 -0700 Received: from b03ledav003.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3DECF6A042; Tue, 20 Sep 2016 11:06:06 -0600 (MDT) Received: from localhost (unknown [9.53.92.191]) by b03ledav003.gho.boulder.ibm.com (Postfix) with ESMTP id 28AFB6A03D; Tue, 20 Sep 2016 11:06:06 -0600 (MDT) From: Michael Roth To: qemu-devel@nongnu.org Date: Tue, 20 Sep 2016 12:05:32 -0500 X-Mailer: git-send-email 1.9.1 In-Reply-To: <1474391141-16623-1-git-send-email-mdroth@linux.vnet.ibm.com> References: <1474391141-16623-1-git-send-email-mdroth@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16092017-0028-0000-0000-000005A5C57F X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00005792; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000185; SDB=6.00759545; UDB=6.00361078; IPR=6.00533874; BA=6.00004739; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00012728; XFM=3.00000011; UTC=2016-09-20 17:06:08 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16092017-0029-0000-0000-00002F66140D Message-Id: <1474391141-16623-17-git-send-email-mdroth@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2016-09-20_07:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=29 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1609020000 definitions=main-1609200216 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] X-Received-From: 148.163.156.1 Subject: [Qemu-devel] [PATCH 16/25] scsi: pvscsi: limit process IO loop to ring size X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , qemu-stable@nongnu.org, Prasad J Pandit Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Prasad J Pandit Vmware Paravirtual SCSI emulator while processing IO requests could run into an infinite loop if 'pvscsi_ring_pop_req_descr' always returned positive value. Limit IO loop to the ring size. Cc: qemu-stable@nongnu.org Reported-by: Li Qiang Signed-off-by: Prasad J Pandit Message-Id: <1473845952-30785-1-git-send-email-ppandit@redhat.com> Signed-off-by: Paolo Bonzini (cherry picked from commit d251157ac1928191af851d199a9ff255d330bec9) Signed-off-by: Michael Roth --- hw/scsi/vmw_pvscsi.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c index 2d7528d..fe74d86 100644 --- a/hw/scsi/vmw_pvscsi.c +++ b/hw/scsi/vmw_pvscsi.c @@ -252,8 +252,11 @@ static hwaddr pvscsi_ring_pop_req_descr(PVSCSIRingInfo *mgr) { uint32_t ready_ptr = RS_GET_FIELD(mgr, reqProdIdx); + uint32_t ring_size = PVSCSI_MAX_NUM_PAGES_REQ_RING + * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE; - if (ready_ptr != mgr->consumed_ptr) { + if (ready_ptr != mgr->consumed_ptr + && ready_ptr - mgr->consumed_ptr < ring_size) { uint32_t next_ready_ptr = mgr->consumed_ptr++ & mgr->txr_len_mask; uint32_t next_ready_page =