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>

1 files changed, 11 insertions, 1 deletions

diff --git a/drivers/media/video/pvrusb2/pvrusb2-hdw.c b/drivers/media/video/pvrusb2/pvrusb2-hdw.c
index 301ef197d038..d13232d51823 100644
--- 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);
 }