projects / ipfire-2.x.git / blame
| Commit | Line | Data |
|---|---|---|
| 2cb7cef9 BS |
1 | From 9778c14b4ca2c81e437fc2fd2b1f3d676937db27 Mon Sep 17 00:00:00 2001 |
| 2 | From: Taku Izumi <izumi.taku@jp.fujitsu.com> | |
| 3 | Date: Fri, 17 Oct 2008 13:48:36 +0900 | |
| 4 | Subject: ACPI/PCI: Fix possible race condition on _OSC evaluation | |
| 5 | Patch-mainline: 2.6.28 | |
| 6 | References: bnc#438941 | |
| 7 | ||
| 8 | Fix possible race condition on _OSC evaluation. | |
| 9 | ||
| 10 | Current _OSC evaluation code has possible race condition because it | |
| 11 | maniputes osc_data linked list or its contents without any lock | |
| 12 | mechanism. | |
| 13 | ||
| 14 | Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> | |
| 15 | Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com> | |
| 16 | Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> | |
| 17 | Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> | |
| 18 | ||
| 19 | --- | |
| 20 | drivers/pci/pci-acpi.c | 28 ++++++++++++++++++++-------- | |
| 21 | 1 file changed, 20 insertions(+), 8 deletions(-) | |
| 22 | ||
| 23 | --- a/drivers/pci/pci-acpi.c | |
| 24 | +++ b/drivers/pci/pci-acpi.c | |
| 25 | @@ -35,6 +35,8 @@ struct acpi_osc_args { | |
| 26 | u32 query_result; | |
| 27 | }; | |
| 28 | ||
| 29 | +static DEFINE_MUTEX(pci_acpi_lock); | |
| 30 | + | |
| 31 | static struct acpi_osc_data *acpi_get_osc_data(acpi_handle handle) | |
| 32 | { | |
| 33 | struct acpi_osc_data *data; | |
| 34 | @@ -131,10 +133,12 @@ static acpi_status acpi_query_osc(acpi_h | |
| 35 | if (ACPI_FAILURE(status)) | |
| 36 | return status; | |
| 37 | ||
| 38 | + mutex_lock(&pci_acpi_lock); | |
| 39 | osc_data = acpi_get_osc_data(handle); | |
| 40 | if (!osc_data) { | |
| 41 | printk(KERN_ERR "acpi osc data array is full\n"); | |
| 42 | - return AE_ERROR; | |
| 43 | + status = AE_ERROR; | |
| 44 | + goto out; | |
| 45 | } | |
| 46 | ||
| 47 | /* do _OSC query for all possible controls */ | |
| 48 | @@ -149,7 +153,8 @@ static acpi_status acpi_query_osc(acpi_h | |
| 49 | osc_data->query_result = osc_args.query_result; | |
| 50 | osc_data->is_queried = 1; | |
| 51 | } | |
| 52 | - | |
| 53 | +out: | |
| 54 | + mutex_unlock(&pci_acpi_lock); | |
| 55 | return status; | |
| 56 | } | |
| 57 | ||
| 58 | @@ -190,19 +195,25 @@ acpi_status pci_osc_control_set(acpi_han | |
| 59 | if (ACPI_FAILURE(status)) | |
| 60 | return status; | |
| 61 | ||
| 62 | + mutex_lock(&pci_acpi_lock); | |
| 63 | osc_data = acpi_get_osc_data(handle); | |
| 64 | if (!osc_data) { | |
| 65 | printk(KERN_ERR "acpi osc data array is full\n"); | |
| 66 | - return AE_ERROR; | |
| 67 | + status = AE_ERROR; | |
| 68 | + goto out; | |
| 69 | } | |
| 70 | ||
| 71 | ctrlset = (flags & OSC_CONTROL_MASKS); | |
| 72 | - if (!ctrlset) | |
| 73 | - return AE_TYPE; | |
| 74 | + if (!ctrlset) { | |
| 75 | + status = AE_TYPE; | |
| 76 | + goto out; | |
| 77 | + } | |
| 78 | ||
| 79 | if (osc_data->is_queried && | |
| 80 | - ((osc_data->query_result & ctrlset) != ctrlset)) | |
| 81 | - return AE_SUPPORT; | |
| 82 | + ((osc_data->query_result & ctrlset) != ctrlset)) { | |
| 83 | + status = AE_SUPPORT; | |
| 84 | + goto out; | |
| 85 | + } | |
| 86 | ||
| 87 | control_set = osc_data->control_set | ctrlset; | |
| 88 | osc_args.capbuf[OSC_QUERY_TYPE] = 0; | |
| 89 | @@ -211,7 +222,8 @@ acpi_status pci_osc_control_set(acpi_han | |
| 90 | status = acpi_run_osc(handle, &osc_args); | |
| 91 | if (ACPI_SUCCESS(status)) | |
| 92 | osc_data->control_set = control_set; | |
| 93 | - | |
| 94 | +out: | |
| 95 | + mutex_unlock(&pci_acpi_lock); | |
| 96 | return status; | |
| 97 | } | |
| 98 | EXPORT_SYMBOL(pci_osc_control_set); |