From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:51028 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726329AbfGBSJi (ORCPT ); Tue, 2 Jul 2019 14:09:38 -0400 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x62I6u3T061266 for ; Tue, 2 Jul 2019 14:09:36 -0400 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0a-001b2d01.pphosted.com with ESMTP id 2tgb3tjqjg-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 02 Jul 2019 14:09:36 -0400 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 2 Jul 2019 19:09:34 +0100 From: Eric Farman Subject: [PATCH] vfio-ccw: Fix the conversion of Format-0 CCWs to Format-1 Date: Tue, 2 Jul 2019 20:09:28 +0200 Message-Id: <20190702180928.18113-1-farman@linux.ibm.com> Sender: linux-s390-owner@vger.kernel.org List-ID: To: Cornelia Huck , Farhan Ali Cc: Halil Pasic , linux-s390@vger.kernel.org, kvm@vger.kernel.org, Eric Farman When processing Format-0 CCWs, we use the "len" variable as the number of CCWs to convert to Format-1. But that variable contains zero here, and is not a meaningful CCW count until ccwchain_calc_length() returns. Since that routine requires and expects Format-1 CCWs to identify the chaining behavior, the format conversion must be done first. Convert the 2KB we copied even if it's more than we need. Fixes: 7f8e89a8f2fd ("vfio-ccw: Factor out the ccw0-to-ccw1 transition") Reported-by: Farhan Ali Signed-off-by: Eric Farman --- drivers/s390/cio/vfio_ccw_cp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/s390/cio/vfio_ccw_cp.c b/drivers/s390/cio/vfio_ccw_cp.c index 9cddc1288059..a870bde10445 100644 --- a/drivers/s390/cio/vfio_ccw_cp.c +++ b/drivers/s390/cio/vfio_ccw_cp.c @@ -431,7 +431,7 @@ static int ccwchain_handle_ccw(u32 cda, struct channel_program *cp) /* Convert any Format-0 CCWs to Format-1 */ if (!cp->orb.cmd.fmt) - convert_ccw0_to_ccw1(cp->guest_cp, len); + convert_ccw0_to_ccw1(cp->guest_cp, CCWCHAIN_LEN_MAX); /* Count the CCWs in the current chain */ len = ccwchain_calc_length(cda, cp); -- 2.17.1