lkml.org 
[lkml]   [2012]   [Oct]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH 1/2] ACPI: Fix stale pointer access to flags.lockable
Date
On Wednesday 17 of October 2012 07:55:42 Toshi Kani wrote:
> On Wed, 2012-10-17 at 10:25 +0900, Yasuaki Ishimatsu wrote:
> > 2012/10/16 1:34, Toshi Kani wrote:
> > > During hot-remove, acpi_bus_hot_remove_device() calls ACPI _LCK
> > > method when device->flags.lockable is set. However, this device
> > > pointer is stale since the target acpi_device object has been
> > > already kfree'd by acpi_bus_trim().
> > >
> > > The flags.lockable indicates whether or not this ACPI object
> > > implements _LCK method. Fix the stable pointer access by replacing
> > > it with acpi_get_handle() to check if _LCK is implemented.
> > >
> > > Signed-off-by: Toshi Kani <toshi.kani@hp.com>
> >
> > Looks good to me.
> > Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
>
> Thanks Yasuaki for reviewing!

Applied to linux-pm.git/linux-next as v3.8 material.

Thanks,
Rafael


> > > ---
> > > drivers/acpi/scan.c | 6 +++++-
> > > 1 file changed, 5 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
> > > index 1fcb867..ed87f43 100644
> > > --- a/drivers/acpi/scan.c
> > > +++ b/drivers/acpi/scan.c
> > > @@ -97,6 +97,7 @@ void acpi_bus_hot_remove_device(void *context)
> > > struct acpi_eject_event *ej_event = (struct acpi_eject_event *) context;
> > > struct acpi_device *device;
> > > acpi_handle handle = ej_event->handle;
> > > + acpi_handle temp;
> > > struct acpi_object_list arg_list;
> > > union acpi_object arg;
> > > acpi_status status = AE_OK;
> > > @@ -117,13 +118,16 @@ void acpi_bus_hot_remove_device(void *context)
> > > goto err_out;
> > > }
> > >
> > > + /* device has been freed */
> > > + device = NULL;
> > > +
> > > /* power off device */
> > > status = acpi_evaluate_object(handle, "_PS3", NULL, NULL);
> > > if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
> > > printk(KERN_WARNING PREFIX
> > > "Power-off device failed\n");
> > >
> > > - if (device->flags.lockable) {
> > > + if (ACPI_SUCCESS(acpi_get_handle(handle, "_LCK", &temp))) {
> > > arg_list.count = 1;
> > > arg_list.pointer = &arg;
> > > arg.type = ACPI_TYPE_INTEGER;
> > >
> >
> >
>
>
>
--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.


\
 
 \ /
  Last update: 2012-10-25 02:21    [W:0.069 / U:0.580 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site