From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934360AbdKBD4M (ORCPT ); Wed, 1 Nov 2017 23:56:12 -0400 Received: from mga14.intel.com ([192.55.52.115]:26843 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934073AbdKBD4J (ORCPT ); Wed, 1 Nov 2017 23:56:09 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.44,331,1505804400"; d="scan'208";a="144940675" From: changbin.du@intel.com To: bhelgaas@google.com Cc: tglx@linutronix.de, mingo@redhat.com, x86@kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Changbin Du Subject: [PATCH] PCI: Fail pci_map_rom if the PCI ROM is invalid Date: Thu, 2 Nov 2017 11:48:42 +0800 Message-Id: <1509594522-6841-1-git-send-email-changbin.du@intel.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Changbin Du If we detected a invalid PCI ROM (e.g. Invalid PCI ROM header signature), we should unmap it immediately and fail. It doesn't make any sense that return a mapped area with size of 0. I have seen this case on Intel GVTg vGPU, which have no vbios. It will not cause a real problem, but we should skip it as early as possible. Signed-off-by: Changbin Du --- drivers/pci/rom.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/pci/rom.c b/drivers/pci/rom.c index b6edb18..1f5e6af 100644 --- a/drivers/pci/rom.c +++ b/drivers/pci/rom.c @@ -147,12 +147,8 @@ void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size) return NULL; rom = ioremap(start, *size); - if (!rom) { - /* restore enable if ioremap fails */ - if (!(res->flags & IORESOURCE_ROM_ENABLE)) - pci_disable_rom(pdev); - return NULL; - } + if (!rom) + goto err_ioremap; /* * Try to find the true size of the ROM since sometimes the PCI window @@ -160,7 +156,18 @@ void __iomem *pci_map_rom(struct pci_dev *pdev, size_t *size) * True size is important if the ROM is going to be copied. */ *size = pci_get_rom_size(pdev, rom, *size); + if (!*size) + goto invalid_rom; + return rom; + +invalid_rom: + iounmap(rom); +err_ioremap: + /* restore enable if ioremap fails */ + if (!(res->flags & IORESOURCE_ROM_ENABLE)) + pci_disable_rom(pdev); + return NULL; } EXPORT_SYMBOL(pci_map_rom); -- 2.7.4