summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorLarry Finger <Larry.Finger@lwfinger.net>2009-11-05 10:37:03 -0600
committerGreg Kroah-Hartman <gregkh@suse.de>2009-12-11 11:55:20 -0800
commit85e034fdff2af6befc55904f3ab9cc5aa31be8fe (patch)
tree6128ed2bcfd50c1dedcf3cb61e752266708fdef5
parent796c8c78801ebf1bdebddda06a43276355ff91eb (diff)
downloadop-kernel-dev-85e034fdff2af6befc55904f3ab9cc5aa31be8fe.zip
op-kernel-dev-85e034fdff2af6befc55904f3ab9cc5aa31be8fe.tar.gz
USB: Check results of dma_map_single
In map_urb_for_dma(), the DMA address returned by dma_map_single() is not checked to determine if it is legal. This lack of checking contributed to a problem with the libertas wireless driver (http://marc.info/?l=linux-wireless&m=125695331205062&w=2). The difficulty was not detected until the buffer was unmapped. By this time memory corruption had occurred. The situation is fixed by testing the returned DMA address, and returning -EAGAIN if the address is invalid. Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> Cc: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r--drivers/usb/core/hcd.c14
1 files changed, 10 insertions, 4 deletions
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 34de475..026ab2f 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1275,13 +1275,16 @@ static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
if (usb_endpoint_xfer_control(&urb->ep->desc)
&& !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP)) {
- if (hcd->self.uses_dma)
+ if (hcd->self.uses_dma) {
urb->setup_dma = dma_map_single(
hcd->self.controller,
urb->setup_packet,
sizeof(struct usb_ctrlrequest),
DMA_TO_DEVICE);
- else if (hcd->driver->flags & HCD_LOCAL_MEM)
+ if (dma_mapping_error(hcd->self.controller,
+ urb->setup_dma))
+ return -EAGAIN;
+ } else if (hcd->driver->flags & HCD_LOCAL_MEM)
ret = hcd_alloc_coherent(
urb->dev->bus, mem_flags,
&urb->setup_dma,
@@ -1293,13 +1296,16 @@ static int map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb,
dir = usb_urb_dir_in(urb) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
if (ret == 0 && urb->transfer_buffer_length != 0
&& !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) {
- if (hcd->self.uses_dma)
+ if (hcd->self.uses_dma) {
urb->transfer_dma = dma_map_single (
hcd->self.controller,
urb->transfer_buffer,
urb->transfer_buffer_length,
dir);
- else if (hcd->driver->flags & HCD_LOCAL_MEM) {
+ if (dma_mapping_error(hcd->self.controller,
+ urb->transfer_dma))
+ return -EAGAIN;
+ } else if (hcd->driver->flags & HCD_LOCAL_MEM) {
ret = hcd_alloc_coherent(
urb->dev->bus, mem_flags,
&urb->transfer_dma,
OpenPOWER on IntegriCloud