From mboxrd@z Thu Jan 1 00:00:00 1970 From: Helge Deller Subject: [PATCH] sym53c8xx: Avoid undefined behaviour in drivers/scsi/sym53c8xx_2/sym_hipd.c:762 Date: Thu, 10 Aug 2017 21:08:49 +0200 Message-ID: <20170810190849.GA12659@p100.box> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mout.gmx.net ([212.227.15.18]:53110 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752889AbdHJTI4 (ORCPT ); Thu, 10 Aug 2017 15:08:56 -0400 Content-Disposition: inline Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org, James Bottomley , linux-kernel@vger.kernel.org Cc: linux-parisc@vger.kernel.org On parisc I see this UBSAN warning with a sym53c896: UBSAN: Undefined behaviour in ./drivers/scsi/sym53c8xx_2/sym_hipd.c:762:24 index -1903078336 is out of range for type 'u32 [7]' Avoid this warning by switching to dev64_ul(). Signed-off-by: Helge Deller diff --git a/drivers/scsi/sym53c8xx_2/sym_hipd.c b/drivers/scsi/sym53c8xx_2/sym_hipd.c index 6b349e3..15ff285a9 100644 --- a/drivers/scsi/sym53c8xx_2/sym_hipd.c +++ b/drivers/scsi/sym53c8xx_2/sym_hipd.c @@ -759,7 +759,7 @@ static int sym_prepare_setting(struct Scsi_Host *shost, struct sym_hcb *np, stru /* * Maximum synchronous period factor supported by the chip. */ - period = (11 * div_10M[np->clock_divn - 1]) / (4 * np->clock_khz); + period = div64_ul(11 * div_10M[np->clock_divn - 1], 4 * np->clock_khz); np->maxsync = period > 2540 ? 254 : period / 10; /*