V4L/DVB: pvrusb2: Avoid using stack allocated buffers when performing USB I/O

Drivers shouldn't assume that the stack is DMA-safe.

[mchehab@redhat.com: fix patch description]
Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/video/pvrusb2/pvrusb2-hdw.c b/drivers/media/video/pvrusb2/pvrusb2-hdw.c
index 301ef197d038140008b4b5c59290ef467fe4f76d..d13232d518239fabc740ddb836e7d95907c23350 100644 (file)
--- a/drivers/media/video/pvrusb2/pvrusb2-hdw.c
+++ b/drivers/media/video/pvrusb2/pvrusb2-hdw.c
@@ -4084,12 +4084,20 @@ void pvr2_hdw_device_reset(struct pvr2_hdw *hdw)
 
 void pvr2_hdw_cpureset_assert(struct pvr2_hdw *hdw,int val)
 {
-       char da[1];
+       char *da;
        unsigned int pipe;
        int ret;
 
        if (!hdw->usb_dev) return;
 
+       da = kmalloc(16, GFP_KERNEL);
+
+       if (da == NULL) {
+               pvr2_trace(PVR2_TRACE_ERROR_LEGS,
+                          "Unable to allocate memory to control CPU reset");
+               return;
+       }
+
        pvr2_trace(PVR2_TRACE_INIT,"cpureset_assert(%d)",val);
 
        da[0] = val ? 0x01 : 0x00;
@@ -4103,6 +4111,8 @@ void pvr2_hdw_cpureset_assert(struct pvr2_hdw *hdw,int val)
                           "cpureset_assert(%d) error=%d",val,ret);
                pvr2_hdw_render_useless(hdw);
        }
+
+       kfree(da);
 }