[PATCH 3.4 214/214] HID: logitech: dont use stack based dj_report structures

Greg Kroah-Hartman
2014-06-05T04:23:19Z

From: Marc Dionne <marc.c.dionne@gmail.com>

commit d8dc3494f77a5cc3b274bae36f7e74e85cf8a407 upstream.

On a system with a logitech wireless keyboard/mouse and DMA-API debugging
enabled, this warning appears at boot:

kernel: WARNING: at lib/dma-debug.c:929 check_for_stack.part.12+0x70/0xa7()
kernel: Hardware name: MS-7593
kernel: uhci_hcd 0000:00:1d.1: DMA-API: device driver maps memory fromstack [addr=ffff8801b0079c29]

Make logi_dj_recv_query_paired_devices and logi_dj_recv_switch_to_dj_mode
use a structure allocated with kzalloc rather than a stack based one.

Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/hid/hid-logitech-dj.c | 38 ++++++++++++++++++++++++--------------
1 file changed, 24 insertions(+), 14 deletions(-)

--- a/drivers/hid/hid-logitech-dj.c
+++ b/drivers/hid/hid-logitech-dj.c
@@ -474,28 +474,38 @@ static int logi_dj_recv_send_report(stru

static int logi_dj_recv_query_paired_devices(struct dj_receiver_dev *djrcv_dev)
{
- struct dj_report dj_report;
+ struct dj_report *dj_report;
+ int retval;

- memset(&dj_report, 0, sizeof(dj_report));
- dj_report.report_id = REPORT_ID_DJ_SHORT;
- dj_report.device_index = 0xFF;
- dj_report.report_type = REPORT_TYPE_CMD_GET_PAIRED_DEVICES;
- return logi_dj_recv_send_report(djrcv_dev, &dj_report);
+ dj_report = kzalloc(sizeof(dj_report), GFP_KERNEL);
+ if (!dj_report)
+ return -ENOMEM;
+ dj_report->report_id = REPORT_ID_DJ_SHORT;
+ dj_report->device_index = 0xFF;
+ dj_report->report_type = REPORT_TYPE_CMD_GET_PAIRED_DEVICES;
+ retval = logi_dj_recv_send_report(djrcv_dev, dj_report);
+ kfree(dj_report);
+ return retval;
}

static int logi_dj_recv_switch_to_dj_mode(struct dj_receiver_dev *djrcv_dev,
unsigned timeout)
{
- struct dj_report dj_report;
+ struct dj_report *dj_report;
+ int retval;

- memset(&dj_report, 0, sizeof(dj_report));
- dj_report.report_id = REPORT_ID_DJ_SHORT;
- dj_report.device_index = 0xFF;
- dj_report.report_type = REPORT_TYPE_CMD_SWITCH;
- dj_report.report_params[CMD_SWITCH_PARAM_DEVBITFIELD] = 0x3F;
- dj_report.report_params[CMD_SWITCH_PARAM_TIMEOUT_SECONDS] = (u8)timeout;
- return logi_dj_recv_send_report(djrcv_dev, &dj_report);
+ dj_report = kzalloc(sizeof(dj_report), GFP_KERNEL);
+ if (!dj_report)
+ return -ENOMEM;
+ dj_report->report_id = REPORT_ID_DJ_SHORT;
+ dj_report->device_index = 0xFF;
+ dj_report->report_type = REPORT_TYPE_CMD_SWITCH;
+ dj_report->report_params[CMD_SWITCH_PARAM_DEVBITFIELD] = 0x3F;
+ dj_report->report_params[CMD_SWITCH_PARAM_TIMEOUT_SECONDS] = (u8)timeout;
+ retval = logi_dj_recv_send_report(djrcv_dev, dj_report);
+ kfree(dj_report);
+ return retval;
}