[PATCH 4.4 043/135] usb: gadget: lpc32xx_udc: don't dereference ep pointer before null check
From: Sasha Levin <sashal@kernel.org>
Date: 2020-06-29 19:00:37
Also in:
lkml
Subsystem:
the rest, usb subsystem · Maintainers:
Linus Torvalds, Greg Kroah-Hartman
From: Colin Ian King <redacted>
[ Upstream commit eafa80041645cd7604c4357b1a0cd4a3c81f2227 ]
Currently pointer ep is being dereferenced before it is null checked
leading to a null pointer dereference issue. Fix this by only assigning
pointer udc once ep is known to be not null. Also remove a debug
message that requires a valid udc which may not be possible at that
point.
Addresses-Coverity: ("Dereference before null check")
Fixes: 24a28e428351 ("USB: gadget driver for LPC32xx")
Signed-off-by: Colin Ian King <redacted>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/gadget/udc/lpc32xx_udc.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/drivers/usb/gadget/udc/lpc32xx_udc.c b/drivers/usb/gadget/udc/lpc32xx_udc.c
index ea43cb74a6f27..c9590949e4f0a 100644
--- a/drivers/usb/gadget/udc/lpc32xx_udc.c
+++ b/drivers/usb/gadget/udc/lpc32xx_udc.c@@ -1662,17 +1662,17 @@ static int lpc32xx_ep_enable(struct usb_ep *_ep, const struct usb_endpoint_descriptor *desc) { struct lpc32xx_ep *ep = container_of(_ep, struct lpc32xx_ep, ep); - struct lpc32xx_udc *udc = ep->udc; + struct lpc32xx_udc *udc; u16 maxpacket; u32 tmp; unsigned long flags; /* Verify EP data */ if ((!_ep) || (!ep) || (!desc) || - (desc->bDescriptorType != USB_DT_ENDPOINT)) { - dev_dbg(udc->dev, "bad ep or descriptor\n"); + (desc->bDescriptorType != USB_DT_ENDPOINT)) return -EINVAL; - } + + udc = ep->udc; maxpacket = usb_endpoint_maxp(desc); if ((maxpacket == 0) || (maxpacket > ep->maxpacket)) { dev_dbg(udc->dev, "bad ep descriptor's packet size\n");
@@ -1920,7 +1920,7 @@ static int lpc32xx_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req) static int lpc32xx_ep_set_halt(struct usb_ep *_ep, int value) { struct lpc32xx_ep *ep = container_of(_ep, struct lpc32xx_ep, ep); - struct lpc32xx_udc *udc = ep->udc; + struct lpc32xx_udc *udc; unsigned long flags; if ((!ep) || (ep->hwep_num <= 1))
@@ -1930,6 +1930,7 @@ static int lpc32xx_ep_set_halt(struct usb_ep *_ep, int value) if (ep->is_in) return -EAGAIN; + udc = ep->udc; spin_lock_irqsave(&udc->lock, flags); if (value == 1) {
--
2.25.1