[PATCH 5.7 080/265] usb: cdns3: ep0: add spinlock for cdns3_check_new_setup

From: Sasha Levin
Date: Mon Jun 29 2020 - 17:57:26 EST


From: Peter Chen <peter.chen@xxxxxxx>

commit 2587a029fa2a877d0a8dda955ef1b24c94b4bd0e upstream.

The other thread may access other endpoints when the cdns3_check_new_setup
is handling, add spinlock to protect it.

Cc: <stable@xxxxxxxxxxxxxxx>
Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver")
Reviewed-by: Pawel Laszczak <pawell@xxxxxxxxxxx>
Signed-off-by: Peter Chen <peter.chen@xxxxxxx>
Signed-off-by: Felipe Balbi <balbi@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/cdns3/ep0.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/cdns3/ep0.c b/drivers/usb/cdns3/ep0.c
index f785ce84aba62..da4c5eb03d7ee 100644
--- a/drivers/usb/cdns3/ep0.c
+++ b/drivers/usb/cdns3/ep0.c
@@ -712,15 +712,17 @@ static int cdns3_gadget_ep0_queue(struct usb_ep *ep,
int ret = 0;
u8 zlp = 0;

+ spin_lock_irqsave(&priv_dev->lock, flags);
trace_cdns3_ep0_queue(priv_dev, request);

/* cancel the request if controller receive new SETUP packet. */
- if (cdns3_check_new_setup(priv_dev))
+ if (cdns3_check_new_setup(priv_dev)) {
+ spin_unlock_irqrestore(&priv_dev->lock, flags);
return -ECONNRESET;
+ }

/* send STATUS stage. Should be called only for SET_CONFIGURATION */
if (priv_dev->ep0_stage == CDNS3_STATUS_STAGE) {
- spin_lock_irqsave(&priv_dev->lock, flags);
cdns3_select_ep(priv_dev, 0x00);

erdy_sent = !priv_dev->hw_configured_flag;
@@ -745,7 +747,6 @@ static int cdns3_gadget_ep0_queue(struct usb_ep *ep,
return 0;
}

- spin_lock_irqsave(&priv_dev->lock, flags);
if (!list_empty(&priv_ep->pending_req_list)) {
dev_err(priv_dev->dev,
"can't handle multiple requests for ep0\n");
--
2.25.1