This patch fixes an issue that NULL pointer dereference happens when
a gadget driver calls usb_ep_dequeue() for ep0 after disconnected
a usb cable. This is because that usbhsg_try_stop() will call
usbhsg_ep_disable(&dcp->ep) when a usb cable is disconnected and
the pipe of dcp (ep0) is set to NULL.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
---
This patch is based on the latest Felipe's usb.git / testing/fixes branch.
(commit id = 455bfac5ad0a6394835ab10fad68f5ce3053160b)
Perhaps this issue has existed from the first gadget support in this driver...
Changes from v1:
- Rebase the latest testing/fixes branch.
- Revise the commit log.
- Separate other two patches.
(In other words, this is not related to isochronous support)
drivers/usb/renesas_usbhs/mod_gadget.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/renesas_usbhs/mod_gadget.c b/drivers/usb/renesas_usbhs/mod_gadget.c
index de4f97d..8f7a78e 100644
--- a/drivers/usb/renesas_usbhs/mod_gadget.c
+++ b/drivers/usb/renesas_usbhs/mod_gadget.c
@@ -131,7 +131,8 @@ static void __usbhsg_queue_pop(struct usbhsg_uep *uep,
struct device *dev = usbhsg_gpriv_to_dev(gpriv);
struct usbhs_priv *priv = usbhsg_gpriv_to_priv(gpriv);
- dev_dbg(dev, "pipe %d : queue pop\n", usbhs_pipe_number(pipe));
+ if (pipe)
+ dev_dbg(dev, "pipe %d : queue pop\n", usbhs_pipe_number(pipe));
ureq->req.status = status;
spin_unlock(usbhs_priv_to_lock(priv));
@@ -685,7 +686,13 @@ static int usbhsg_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
struct usbhsg_request *ureq = usbhsg_req_to_ureq(req);
struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);
- usbhs_pkt_pop(pipe, usbhsg_ureq_to_pkt(ureq));
+ if (pipe)
+ usbhs_pkt_pop(pipe, usbhsg_ureq_to_pkt(ureq));
+
+ /*
+ * To dequeue a request, this driver should call the usbhsg_queue_pop()
+ * even if the pipe is NULL.
+ */
usbhsg_queue_pop(uep, ureq, -ECONNRESET);
return 0;
--
1.9.1
--
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