Hi, On 11/2/22 22:23, Armin Wolf wrote: > When the DDV interface returns a buffer, it actually > returns a acpi buffer containing an integer (buffer size) > and another acpi buffer (buffer content). > The size of the buffer may be smaller than the size of > the buffer content, which is perfectly valid and should not > be treated as an error. > Also use the buffer size instead of the buffer content size > when accessing the buffer to prevent accessing bogus data. > > Tested on a Dell Inspiron 3505. > > Signed-off-by: Armin Wolf <W_Armin@xxxxxx> Thank you for your patch-series, I've applied the series to my review-hans branch: https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans Note it will show up in my review-hans branch once I've pushed my local branch there, which might take a while. Once I've run some tests on this branch the patches there will be added to the platform-drivers-x86/for-next branch and eventually will be included in the pdx86 pull-request to Linus for the next merge-window. Regards, Hans > --- > drivers/platform/x86/dell/dell-wmi-ddv.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > diff --git a/drivers/platform/x86/dell/dell-wmi-ddv.c b/drivers/platform/x86/dell/dell-wmi-ddv.c > index 699feae3c435..1a001296e8c6 100644 > --- a/drivers/platform/x86/dell/dell-wmi-ddv.c > +++ b/drivers/platform/x86/dell/dell-wmi-ddv.c > @@ -129,9 +129,9 @@ static int dell_wmi_ddv_query_buffer(struct wmi_device *wdev, enum dell_ddv_meth > if (obj->package.elements[1].type != ACPI_TYPE_BUFFER) > goto err_free; > > - if (buffer_size != obj->package.elements[1].buffer.length) { > + if (buffer_size > obj->package.elements[1].buffer.length) { > dev_warn(&wdev->dev, > - FW_WARN "ACPI buffer size (%llu) does not match WMI buffer size (%d)\n", > + FW_WARN "WMI buffer size (%llu) exceeds ACPI buffer size (%d)\n", > buffer_size, obj->package.elements[1].buffer.length); > > goto err_free; > @@ -271,15 +271,17 @@ static int dell_wmi_ddv_buffer_read(struct seq_file *seq, enum dell_ddv_method m > struct device *dev = seq->private; > struct dell_wmi_ddv_data *data = dev_get_drvdata(dev); > union acpi_object *obj; > - union acpi_object buf; > + u64 size; > + u8 *buf; > int ret; > > ret = dell_wmi_ddv_query_buffer(data->wdev, method, 0, &obj); > if (ret < 0) > return ret; > > - buf = obj->package.elements[1]; > - ret = seq_write(seq, buf.buffer.pointer, buf.buffer.length); > + size = obj->package.elements[0].integer.value; > + buf = obj->package.elements[1].buffer.pointer; > + ret = seq_write(seq, buf, size); > kfree(obj); > > return ret; > -- > 2.30.2 >
