[PATCH 3/6] usb: xhci: Abort transfers with unallocated rings

[Janne Grunau via B4 Relay]

From: Janne Grunau <j at jannau.net>

Discovered while trying to use the second interface in the USB keyboard
driver necessary on Apple USB keyboards.

Signed-off-by: Janne Grunau <j at jannau.net>
---
 drivers/usb/host/xhci-ring.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index b60661fe05..4446f5f098 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -685,6 +685,9 @@ int xhci_bulk_tx(struct usb_device *udev, unsigned long pipe,
 		reset_ep(udev, ep_index);
 
 	ring = virt_dev->eps[ep_index].ring;
+	if (!ring)
+		return -1;
+
 	/*
 	 * How much data is (potentially) left before the 64KB boundary?
 	 * XHCI Spec puts restriction( TABLE 49 and 6.4.1 section of XHCI Spec)
@@ -871,6 +874,8 @@ int xhci_ctrl_tx(struct usb_device *udev, unsigned long pipe,
 	ep_index = usb_pipe_ep_index(pipe);
 
 	ep_ring = virt_dev->eps[ep_index].ring;
+	if (!ep_ring)
+		return -1;
 
 	/*
 	 * Check to see if the max packet size for the default control

-- 
2.43.2