From patchwork Tue Jan 12 14:42:29 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hannes Reinecke X-Patchwork-Id: 8017991 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: patchwork-linux-pci@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id A119CBEEE5 for ; Tue, 12 Jan 2016 14:44:11 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id DFDC5203C4 for ; Tue, 12 Jan 2016 14:44:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F2BEE20320 for ; Tue, 12 Jan 2016 14:44:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964979AbcALOmh (ORCPT ); Tue, 12 Jan 2016 09:42:37 -0500 Received: from mx2.suse.de ([195.135.220.15]:60795 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964936AbcALOmf (ORCPT ); Tue, 12 Jan 2016 09:42:35 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 6E1DFAC2E; Tue, 12 Jan 2016 14:42:31 +0000 (UTC) From: Hannes Reinecke To: Bjorn Helgaas Cc: Alexander Duyck , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Babu Moger , Hannes Reinecke Subject: [PATCH 2/3] pci: Update VPD size with correct length Date: Tue, 12 Jan 2016 15:42:29 +0100 Message-Id: <1452609750-90760-3-git-send-email-hare@suse.de> X-Mailer: git-send-email 1.8.5.6 In-Reply-To: <1452609750-90760-1-git-send-email-hare@suse.de> References: <1452609750-90760-1-git-send-email-hare@suse.de> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP PCI-2.2 VPD entries have a maximum size of 32k, but might actually be smaller than that. To figure out the actual size one has to read the VPD area until the 'end marker' is reached. Trying to read VPD data beyond that marker results in 'interesting' effects, from simple read errors to crashing the card. And to make matters worse not every PCI card implements this properly, leaving us with no 'end' marker or even completely invalid data. This path modifies the size of the VPD attribute to the available size, or set it to '0' if the VPD attribute couldn't be read. Cc: Alexander Duyck Cc: Bjorn Helgaas Signed-off-by: Hannes Reinecke --- drivers/pci/access.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) diff --git a/drivers/pci/access.c b/drivers/pci/access.c index 59ac36f..ce1b0cb 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -475,6 +475,61 @@ static const struct pci_vpd_ops pci_vpd_f0_ops = { .release = pci_vpd_pci22_release, }; +/** + * pci_vpd_size - determine actual size of Vital Product Data + * @dev: pci device struct + * @old_size: current assumed size, also maximum allowed size + * + */ +static size_t +pci_vpd_pci22_size(struct pci_dev *dev) +{ + size_t off = 0; + unsigned char header[1+2]; /* 1 byte tag, 2 bytes length */ + + while (off < PCI_VPD_PCI22_SIZE && + pci_read_vpd(dev, off, 1, header) == 1) { + unsigned char tag; + + if (header[0] & PCI_VPD_LRDT) { + /* Large Resource Data Type Tag */ + tag = pci_vpd_lrdt_tag(header); + /* Only read length from known tag items */ + if ((tag == PCI_VPD_LTIN_ID_STRING) || + (tag == PCI_VPD_LTIN_RO_DATA) || + (tag == PCI_VPD_LTIN_RW_DATA)) { + if (pci_read_vpd(dev, off+1, 2, + &header[1]) != 2) { + dev_dbg(&dev->dev, + "invalid large vpd tag %02x " + "size at offset %zu", + tag, off + 1); + break; + } + off += PCI_VPD_LRDT_TAG_SIZE + + pci_vpd_lrdt_size(header); + } + } else { + /* Short Resource Data Type Tag */ + off += PCI_VPD_SRDT_TAG_SIZE + + pci_vpd_srdt_size(header); + tag = pci_vpd_srdt_tag(header); + } + if (tag == PCI_VPD_STIN_END) /* End tag descriptor */ + return off; + if ((tag != PCI_VPD_LTIN_ID_STRING) && + (tag != PCI_VPD_LTIN_RO_DATA) && + (tag != PCI_VPD_LTIN_RW_DATA)) { + dev_dbg(&dev->dev, + "invalid %s vpd tag %02x at offset %zu", + (header[0] & PCI_VPD_LRDT) ? "large" : "short", + tag, off); + break; + } + } + return 0; +} + int pci_vpd_pci22_init(struct pci_dev *dev) { struct pci_vpd_pci22 *vpd; @@ -497,6 +552,8 @@ int pci_vpd_pci22_init(struct pci_dev *dev) vpd->cap = cap; vpd->busy = false; dev->vpd = &vpd->base; + if (!(dev->dev_flags & PCI_DEV_FLAGS_VPD_REF_F0)) + vpd->base.len = pci_vpd_pci22_size(dev); return 0; }