[PATCH] drivers: usb: gadget: udc: Fix NULL dereference
From: Tapasweni Pathak
Date: Tue Mar 03 2015 - 07:58:53 EST
This patch fixes multiple instances of null pointer dereference in this code.
ep->udc is assigned to udc. ep is just an offset from _ep. _ep is then
checked for NULL. udc is dereferenced under the NULL check for _ep, making
an invalid pointer reference.
udc is then checked for NULL, if NULL, it is then dereferenced as
udc->dev.
To fix these issues, shift assignment of udc by dereferencing ep after
null check for _ep, replace both dev_dbg statements with pr_debug.
Found using Coccinelle.
Signed-off-by: Tapasweni Pathak <tapaswenipathak@xxxxxxxxx>
Suggested-by : Julia Lawall <julia.lawall@xxxxxxx>
Reviewed-by : Julia Lawall <julia.lawall@xxxxxxx>
---
drivers/usb/gadget/udc/lpc32xx_udc.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/gadget/udc/lpc32xx_udc.c b/drivers/usb/gadget/udc/lpc32xx_udc.c
index 27fd413..6398539 100644
--- a/drivers/usb/gadget/udc/lpc32xx_udc.c
+++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
@@ -1807,17 +1807,16 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
!list_empty(&req->queue))
return -EINVAL;
- udc = ep->udc;
-
if (!_ep) {
- dev_dbg(udc->dev, "invalid ep\n");
+ pr_debug("invalid ep\n");
return -EINVAL;
}
+ udc = ep->udc;
if ((!udc) || (!udc->driver) ||
(udc->gadget.speed == USB_SPEED_UNKNOWN)) {
- dev_dbg(udc->dev, "invalid device\n");
+ pr_debug("invalid device\n");
return -EINVAL;
}
--
1.7.9.5
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