Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752816AbdLNNOW (ORCPT ); Thu, 14 Dec 2017 08:14:22 -0500 Received: from fllnx209.ext.ti.com ([198.47.19.16]:22263 "EHLO fllnx209.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752547AbdLNNOU (ORCPT ); Thu, 14 Dec 2017 08:14:20 -0500 Subject: Re: [PATCH v5 3/3] PCI: endpoint: Fix find_first_zero_bit() usage To: Niklas Cassel , Lorenzo Pieralisi , Bjorn Helgaas References: <20171214130147.1790-1-niklas.cassel@axis.com> <20171214130147.1790-4-niklas.cassel@axis.com> CC: Niklas Cassel , , From: Kishon Vijay Abraham I Message-ID: Date: Thu, 14 Dec 2017 18:43:26 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 MIME-Version: 1.0 In-Reply-To: <20171214130147.1790-4-niklas.cassel@axis.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1322 Lines: 38 On Thursday 14 December 2017 06:31 PM, Niklas Cassel wrote: > find_first_zero_bit()'s parameter 'size' is defined in bits, > not in bytes. > > Calling find_first_zero_bit() with the wrong size unit > will lead to insidious bugs. > > Fix this by calling find_first_zero_bit() with size BITS_PER_LONG, > rather than sizeof() and add missing find_first_zero_bit() return > handling. > > Fixes: d74679911610 ("PCI: endpoint: Introduce configfs entry for configuring EP functions") > Signed-off-by: Niklas Cassel Acked-by: Kishon Vijay Abraham I > --- > drivers/pci/endpoint/pci-ep-cfs.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c > index e8f65eb51c1a..c9a2fb9dd49d 100644 > --- a/drivers/pci/endpoint/pci-ep-cfs.c > +++ b/drivers/pci/endpoint/pci-ep-cfs.c > @@ -103,7 +103,10 @@ static int pci_epc_epf_link(struct config_item *epc_item, > struct pci_epf *epf = epf_group->epf; > > func_no = find_first_zero_bit(&epc_group->function_num_map, > - sizeof(epc_group->function_num_map)); > + BITS_PER_LONG); > + if (func_no >= BITS_PER_LONG) > + return -EINVAL; > + > set_bit(func_no, &epc_group->function_num_map); > epf->func_no = func_no; > >