USB: EHCI: adjust ehci_iso_stream for changes in ehci_qh

The EHCI driver stores in usb_host_endpoint.hcpriv a pointer to either
an ehci_qh or an ehci_iso_stream structure, and uses the contents of the
hw_info1 field to distinguish the two cases.

After ehci_qh was split into hw and sw parts, ehci_iso_stream must also
be adjusted so that it again looks like an ehci_qh structure.

This fixes a NULL pointer access in ehci_endpoint_disable() when it
tries to access qh->hw->hw_info1.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Reported-by: Colin Fletcher <colin.m.fletcher@googlemail.com>
Cc: stable <stable@kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 5 insertions, 6 deletions

diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index d8d6d3461d32..dc55a62859c6 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -995,7 +995,7 @@ rescan:
         /* endpoints can be iso streams.  for now, we don't
          * accelerate iso completions ... so spin a while.
          */
-        if (qh->hw->hw_info1 == 0) {
+        if (qh->hw == NULL) {
                 ehci_vdbg (ehci, "iso delay\n");
                 goto idle_timeout;
         }
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index cd1e8bf5327e..a0aaaaff2560 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -1123,8 +1123,8 @@ iso_stream_find (struct ehci_hcd *ehci, struct urb *urb)
                                         urb->interval);
                 }
 
-        /* if dev->ep [epnum] is a QH, info1.maxpacket is nonzero */
-        } else if (unlikely (stream->hw_info1 != 0)) {
+        /* if dev->ep [epnum] is a QH, hw is set */
+        } else if (unlikely (stream->hw != NULL)) {
                 ehci_dbg (ehci, "dev %s ep%d%s, not iso??\n",
                         urb->dev->devpath, epnum,
                         usb_pipein(urb->pipe) ? "in" : "out");
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 2d85e21ff282..b1dce96dd621 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -394,9 +394,8 @@ struct ehci_iso_sched {
  * acts like a qh would, if EHCI had them for ISO.
  */
 struct ehci_iso_stream {
-        /* first two fields match QH, but info1 == 0 */
-        __hc32                  hw_next;
-        __hc32                  hw_info1;
+        /* first field matches ehci_hq, but is NULL */
+        struct ehci_qh_hw       *hw;
 
         u32                     refcount;
         u8                      bEndpointAddress;