From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:32844) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bhUi9-0008MX-0U for qemu-devel@nongnu.org; Wed, 07 Sep 2016 00:43:45 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bhUi3-0002Ge-MA for qemu-devel@nongnu.org; Wed, 07 Sep 2016 00:43:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:49242) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bhUi3-0002GD-GJ for qemu-devel@nongnu.org; Wed, 07 Sep 2016 00:43:39 -0400 From: P J P Date: Wed, 7 Sep 2016 10:13:28 +0530 Message-Id: <1473223408-24079-1-git-send-email-ppandit@redhat.com> Subject: [Qemu-devel] [PATCH] scsi: pvscsi: limit process IO loop to maximum page count List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Qemu Developers Cc: Paolo Bonzini , Dmitry Fleytman , Li Qiang , Prasad J Pandit 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 maximum page count. Reported-by: Li Qiang Signed-off-by: Prasad J Pandit --- hw/scsi/vmw_pvscsi.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c index babac5a..3e77a08 100644 --- a/hw/scsi/vmw_pvscsi.c +++ b/hw/scsi/vmw_pvscsi.c @@ -711,11 +711,13 @@ pvscsi_process_request_descriptor(PVSCSIState *s, static void pvscsi_process_io(PVSCSIState *s) { + int descr_pa_cnt = 0; PVSCSIRingReqDesc descr; hwaddr next_descr_pa; assert(s->rings_info_valid); - while ((next_descr_pa = pvscsi_ring_pop_req_descr(&s->rings)) != 0) { + while (((next_descr_pa = pvscsi_ring_pop_req_descr(&s->rings)) != 0) + && descr_pa_cnt++ < PVSCSI_SETUP_RINGS_MAX_NUM_PAGES) { /* Only read after production index verification */ smp_rmb(); -- 2.5.5