diff options
| author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-08-06 02:26:22 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-08-14 22:59:07 -0700 |
| commit | b97f921b94b1e70d5de999fd820ccf8504dc6528 (patch) | |
| tree | 66c405bdc3086d5519c2d16ce07a65016d2967f2 | |
| parent | da712f3a8c493986b19fd0863b45607c34061ba6 (diff) | |
ACPI / PM: Walk physical_node_list under physical_node_lock
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 <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/acpi/proc.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/drivers/acpi/proc.c b/drivers/acpi/proc.c index aa1227a7e3f..04a13784dd2 100644 --- a/drivers/acpi/proc.c +++ b/drivers/acpi/proc.c @@ -311,6 +311,8 @@ acpi_system_wakeup_device_seq_show(struct seq_file *seq, void *offset) 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(struct seq_file *seq, void *offset) 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_wakeup(struct acpi_device *adev) { 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 |