Re: [PATCH] usbip: Fix vep_free_request() null pointer checks on input args

From: shuah
Date: Fri Jan 25 2019 - 09:27:16 EST

On 1/25/19 1:02 AM, Greg KH wrote:
On Tue, Jan 22, 2019 at 04:05:28PM -0700, shuah wrote:
On 1/19/19 1:17 AM, Greg KH wrote:
On Fri, Jan 18, 2019 at 02:29:30PM -0700, Shuah Khan wrote:
From: Shuah Khan <shuah@xxxxxxxxxx>

Fix vep_free_request() to return when usb_ep and usb_request are null
instead of calling WARN_ON.

Signed-off-by: Shuah Khan <shuah@xxxxxxxxxx>
drivers/usb/usbip/vudc_dev.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/usbip/vudc_dev.c b/drivers/usb/usbip/vudc_dev.c
index 1634d8698e15..bfc8218e3fb6 100644
--- a/drivers/usb/usbip/vudc_dev.c
+++ b/drivers/usb/usbip/vudc_dev.c
@@ -297,7 +297,7 @@ static void vep_free_request(struct usb_ep *_ep, struct usb_request *_req)
struct vrequest *req;
- if (WARN_ON(!_ep || !_req))
+ if (!_ep || !_req)

It's impossible for _ep to be NULL in this callback (see
usb_ep_free_request() for where this is called from to prove that), so I
don't think you need to check that. It's almost impossible for _req to
be NULL, so you might as well leave that check in.

Yes. ep can never be null here in vep_free_request(). I will leave
this alone.

You can drop the !_ep check at the least, no need to check something
that is impossible to hit :)

Thanks. I will do that.

-- Shuah