[PATCH 4.14 208/209] platform/x86: hp-wmi: Fix ACPI errors caused by passing 0 as input size

Greg Kroah-Hartman
2019-12-04T18:19:31Z

From: Hans de Goede <hdegoede@redhat.com>

commit f3e4f3fc8ee9729c4b1b27a478c68b713df53c0c upstream.

The AML code implementing the WMI methods creates a variable length
field to hold the input data we pass like this:

CreateDWordField (Arg1, 0x0C, DSZI)
Local5 = DSZI /* \HWMC.DSZI */
CreateField (Arg1, 0x80, (Local5 * 0x08), DAIN)

If we pass 0 as bios_args.datasize argument then (Local5 * 0x08)
is 0 which results in these errors:

[ 71.973305] ACPI BIOS Error (bug): Attempt to CreateField of length zero (20190816/dsopcode-133)
[ 71.973332] ACPI Error: Aborting method \HWMC due to previous error (AE_AML_OPERAND_VALUE) (20190816/psparse-529)
[ 71.973413] ACPI Error: Aborting method \_SB.WMID.WMAA due to previous error (AE_AML_OPERAND_VALUE) (20190816/psparse-529)

And in our HPWMI_WIRELESS2_QUERY calls always failing. for read commands
like HPWMI_WIRELESS2_QUERY the DSZI value is not used / checked, except for
read commands where extra input is needed to specify exactly what to read.

So for HPWMI_WIRELESS2_QUERY we can safely pass the size of the expected
output as insize to hp_wmi_perform_query(), as we are already doing for all
other HPWMI_READ commands we send. Doing so fixes these errors.

Cc: stable@vger.kernel.org
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=197007
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=201981
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1520703
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/platform/x86/hp-wmi.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/platform/x86/hp-wmi.c
+++ b/drivers/platform/x86/hp-wmi.c
@@ -393,7 +393,7 @@ static int hp_wmi_rfkill2_refresh(void)
int err, i;

err = hp_wmi_perform_query(HPWMI_WIRELESS2_QUERY, HPWMI_READ, &state,
- 0, sizeof(state));
+ sizeof(state), sizeof(state));
if (err)
return err;

@@ -790,7 +790,7 @@ static int __init hp_wmi_rfkill2_setup(s
int err, i;

err = hp_wmi_perform_query(HPWMI_WIRELESS2_QUERY, HPWMI_READ, &state,
- 0, sizeof(state));
+ sizeof(state), sizeof(state));
if (err)
return err < 0 ? err : -EINVAL;