From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bastet.se.axis.com ([195.60.68.11]:40346 "EHLO bastet.se.axis.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752844AbdK0PuV (ORCPT ); Mon, 27 Nov 2017 10:50:21 -0500 From: Niklas Cassel To: Kishon Vijay Abraham I , Lorenzo Pieralisi , Bjorn Helgaas Cc: Niklas Cassel , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 3/3] PCI: endpoint: Fix find_first_zero_bit() usage Date: Mon, 27 Nov 2017 16:49:55 +0100 Message-Id: <20171127154955.22214-4-niklas.cassel@axis.com> In-Reply-To: <20171127154955.22214-1-niklas.cassel@axis.com> References: <20171127154955.22214-1-niklas.cassel@axis.com> Sender: linux-pci-owner@vger.kernel.org List-ID: 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(). Also add proper error handling for find_first_zero_bit(), since this was missing. Fixes: d74679911610 ("PCI: endpoint: Introduce configfs entry for configuring EP functions") Signed-off-by: Niklas Cassel --- drivers/pci/endpoint/pci-ep-cfs.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c index e1f5adc9e113..0a22a7976580 100644 --- a/drivers/pci/endpoint/pci-ep-cfs.c +++ b/drivers/pci/endpoint/pci-ep-cfs.c @@ -109,7 +109,12 @@ static int pci_epc_epf_link(struct config_item *epc_item, return ret; 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) { + ret = -EINVAL; + dev_err(&epc->dev, "failed to link endpoint function device\n"); + goto err_func_no; + } set_bit(func_no, &epc_group->function_num_map); epf->func_no = func_no; @@ -121,6 +126,7 @@ static int pci_epc_epf_link(struct config_item *epc_item, err_epf_bind: clear_bit(func_no, &epc_group->function_num_map); +err_func_no: pci_epc_remove_epf(epc, epf); return ret; -- 2.14.2