From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757926Ab3HMGzv (ORCPT ); Tue, 13 Aug 2013 02:55:51 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:60499 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756324Ab3HMGdN (ORCPT ); Tue, 13 Aug 2013 02:33:13 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Rafael J. Wysocki" Subject: [ 21/60] ACPI / PM: Walk physical_node_list under physical_node_lock Date: Mon, 12 Aug 2013 23:33:48 -0700 Message-Id: <20130813063334.984600825@linuxfoundation.org> X-Mailer: git-send-email 1.8.3.3.825.g36032ce.dirty In-Reply-To: <20130813063331.950321483@linuxfoundation.org> References: <20130813063331.950321483@linuxfoundation.org> User-Agent: quilt/0.60-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Rafael J. Wysocki" commit 623cf33cb055b1e81fa47e4fc16789b2c129e31e upstream. The list of physical devices corresponding to an ACPI device object is walked by acpi_system_wakeup_device_seq_show() and physical_device_enable_wakeup() without taking that object's physical_node_lock mutex. Since each of those functions may be run at any time as a result of a user space action, the lack of appropriate locking in them may lead to a kernel crash if that happens during device hot-add or hot-remove involving the device object in question. Fix the issue by modifying acpi_system_wakeup_device_seq_show() and physical_device_enable_wakeup() to use physical_node_lock as appropriate. Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman --- drivers/acpi/proc.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/drivers/acpi/proc.c +++ b/drivers/acpi/proc.c @@ -311,6 +311,8 @@ acpi_system_wakeup_device_seq_show(struc dev->pnp.bus_id, (u32) dev->wakeup.sleep_state); + mutex_lock(&dev->physical_node_lock); + if (!dev->physical_node_count) { seq_printf(seq, "%c%-8s\n", dev->wakeup.flags.run_wake ? '*' : ' ', @@ -338,6 +340,8 @@ acpi_system_wakeup_device_seq_show(struc put_device(ldev); } } + + mutex_unlock(&dev->physical_node_lock); } mutex_unlock(&acpi_device_lock); return 0; @@ -347,12 +351,16 @@ static void physical_device_enable_wakeu { struct acpi_device_physical_node *entry; + mutex_lock(&adev->physical_node_lock); + list_for_each_entry(entry, &adev->physical_node_list, node) if (entry->dev && device_can_wakeup(entry->dev)) { bool enable = !device_may_wakeup(entry->dev); device_set_wakeup_enable(entry->dev, enable); } + + mutex_unlock(&adev->physical_node_lock); } static ssize_t