Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Joerg Roedel , "Rafael J. Wysocki" Subject: [PATCH 4.9 81/84] ACPI: ioapic: Clear on-stack resource before using it Date: Mon, 28 Aug 2017 10:05:46 +0200 Message-Id: <20170828080532.668564353@linuxfoundation.org> In-Reply-To: <20170828080529.526391781@linuxfoundation.org> References: <20170828080529.526391781@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Joerg Roedel commit e3d5092b6756b9e0b08f94bbeafcc7afe19f0996 upstream. The on-stack resource-window 'win' in setup_res() is not properly initialized. This causes the pointers in the embedded 'struct resource' to contain stale addresses. These pointers (in my case the ->child pointer) later get propagated to the global iomem_resources list, causing a #GP exception when the list is traversed in iomem_map_sanity_check(). Fixes: c183619b63ec (x86/irq, ACPI: Implement ACPI driver to support IOAPIC hotplug) Signed-off-by: Joerg Roedel Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/acpi/ioapic.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/acpi/ioapic.c +++ b/drivers/acpi/ioapic.c @@ -45,6 +45,12 @@ static acpi_status setup_res(struct acpi struct resource *res = data; struct resource_win win; + /* + * We might assign this to 'res' later, make sure all pointers are + * cleared before the resource is added to the global list + */ + memset(&win, 0, sizeof(win)); + res->flags = 0; if (acpi_dev_filter_resource_type(acpi_res, IORESOURCE_MEM)) return AE_OK;