From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760497AbbA1EN6 (ORCPT ); Tue, 27 Jan 2015 23:13:58 -0500 Received: from mail.kernel.org ([198.145.29.136]:36770 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760424AbbA1ENz (ORCPT ); Tue, 27 Jan 2015 23:13:55 -0500 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Andreas Noever , Bjorn Helgaas , Zefan Li Subject: [PATCH 3.4 007/177] PCI: pciehp: Prevent NULL dereference during probe Date: Wed, 28 Jan 2015 12:06:21 +0800 Message-Id: <1422418236-12852-14-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1422418050-12581-1-git-send-email-lizf@kernel.org> References: <1422418050-12581-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andreas Noever 3.4.106-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit bceee4a97eb58bd0e80e39eff11b506ddd9e7ad3 upstream. pciehp assumes that dev->subordinate, the struct pci_bus for a bridge's secondary bus, exists. But we do not create that bus if we run out of bus numbers during enumeration. This leads to a NULL dereference in init_slot() (and other places). Change pciehp_probe() to return -ENODEV when no secondary bus is present. Signed-off-by: Andreas Noever Signed-off-by: Bjorn Helgaas Signed-off-by: Zefan Li --- drivers/pci/hotplug/pciehp_core.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c index 9e39df9..75dc402 100644 --- a/drivers/pci/hotplug/pciehp_core.c +++ b/drivers/pci/hotplug/pciehp_core.c @@ -237,6 +237,13 @@ static int pciehp_probe(struct pcie_device *dev) else if (pciehp_acpi_slot_detection_check(dev->port)) goto err_out_none; + if (!dev->port->subordinate) { + /* Can happen if we run out of bus numbers during probe */ + dev_err(&dev->device, + "Hotplug bridge without secondary bus, ignoring\n"); + goto err_out_none; + } + ctrl = pcie_init(dev); if (!ctrl) { dev_err(&dev->device, "Controller initialization failed\n"); -- 1.9.1