HID: lenovo: Don't use stack variables for DMA buffers
The lenovo_send_cmd_cptkbd function uses a stack variable to submit
commands via hid_hw_raw_request. Eventually this gets to the
usb_hcd_map_urb_for_dma function, which causes a warning to be thrown
if the CONFIG_DMA_API_DEBUG option is enabled.
Fix this by allocating a temporary buffer instead.
[jkosina@suse.cz: no need to NULL-initialize buf, spotted by Benjamin]
Reported-by: lejeczek <peljasz@yahoo.co.uk>
Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-lenovo.c b/drivers/hid/hid-lenovo.c
index 0125e35..1ac4ff4 100644
--- a/drivers/hid/hid-lenovo.c
+++ b/drivers/hid/hid-lenovo.c
@@ -184,21 +184,31 @@
unsigned char byte2, unsigned char byte3)
{
int ret;
- unsigned char buf[] = {0x18, byte2, byte3};
+ unsigned char *buf;
+
+ buf = kzalloc(3, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ buf[0] = 0x18;
+ buf[1] = byte2;
+ buf[2] = byte3;
switch (hdev->product) {
case USB_DEVICE_ID_LENOVO_CUSBKBD:
- ret = hid_hw_raw_request(hdev, 0x13, buf, sizeof(buf),
+ ret = hid_hw_raw_request(hdev, 0x13, buf, 3,
HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
break;
case USB_DEVICE_ID_LENOVO_CBTKBD:
- ret = hid_hw_output_report(hdev, buf, sizeof(buf));
+ ret = hid_hw_output_report(hdev, buf, 3);
break;
default:
ret = -EINVAL;
break;
}
+ kfree(buf);
+
return ret < 0 ? ret : 0; /* BT returns 0, USB returns sizeof(buf) */
}
