[PATCH 5.18 0794/1095] usb: cdns3: change place of priv_ep assignment in cdns3_gadget_ep_dequeue(), cdns3_gadget_ep_enable()

Greg Kroah-Hartman
2022-08-15T22:24:56Z

From: Andrey Strachuk <strochuk@ispras.ru>

[ Upstream commit c3ffc9c4ca44bfe9562166793d133e1fb0630ea6 ]

If 'ep' is NULL, result of ep_to_cdns3_ep(ep) is invalid pointer
and its dereference with priv_ep->cdns3_dev may cause panic.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 7733f6c32e36 ("usb: cdns3: Add Cadence USB3 DRD Driver")
Acked-by: Peter Chen <peter.chen@kernel.org>
Signed-off-by: Andrey Strachuk <strochuk@ispras.ru>
Link: https://lore.kernel.org/r/20220718160052.4188-1-strochuk@ispras.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/cdns3/cdns3-gadget.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/cdns3/cdns3-gadget.c b/drivers/usb/cdns3/cdns3-gadget.c
index d6d515d598dc..e0cf62e65075 100644
--- a/drivers/usb/cdns3/cdns3-gadget.c
+++ b/drivers/usb/cdns3/cdns3-gadget.c
@@ -2281,14 +2281,15 @@ static int cdns3_gadget_ep_enable(struct usb_ep *ep,
int val;

priv_ep = ep_to_cdns3_ep(ep);
- priv_dev = priv_ep->cdns3_dev;
- comp_desc = priv_ep->endpoint.comp_desc;

if (!ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
dev_dbg(priv_dev->dev, "usbss: invalid parameters\n");
return -EINVAL;
}

+ comp_desc = priv_ep->endpoint.comp_desc;
+ priv_dev = priv_ep->cdns3_dev;
+
if (!desc->wMaxPacketSize) {
dev_err(priv_dev->dev, "usbss: missing wMaxPacketSize\n");
return -EINVAL;
@@ -2596,7 +2597,7 @@ int cdns3_gadget_ep_dequeue(struct usb_ep *ep,
struct usb_request *request)
{
struct cdns3_endpoint *priv_ep = ep_to_cdns3_ep(ep);
- struct cdns3_device *priv_dev = priv_ep->cdns3_dev;
+ struct cdns3_device *priv_dev;
struct usb_request *req, *req_temp;
struct cdns3_request *priv_req;
struct cdns3_trb *link_trb;
@@ -2607,6 +2608,8 @@ int cdns3_gadget_ep_dequeue(struct usb_ep *ep,
if (!ep || !request || !ep->desc)
return -EINVAL;

+ priv_dev = priv_ep->cdns3_dev;
+
spin_lock_irqsave(&priv_dev->lock, flags);

priv_req = to_cdns3_request(request);
--
2.35.1