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Date:   Fri, 6 May 2022 10:10:23 +0300
From:   Dan Carpenter <dan.carpenter@oracle.com>
To:     Wang Cheng <wanngchenng@gmail.com>
Cc:     paskripkin@gmail.com, linux-staging@lists.linux.dev,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] staging: rtl8712: fix uninit-value in usb_read8()
 and friends
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Setting "data = 0" will silence the KMSAN warnings but it doesn't fix
the bug which is that r8712_usbctrl_vendorreq() treats partial reads
as success.

The usb_control_msg() returns negatives on total failure and it returns
small positives on partial failure.  So take the code that I gave you
before and put that into r8712_usbctrl_vendorreq().  That's patch 1.
These patches become 2 and 3.

        status = usb_control_msg();
        if (status < 0)
                goto free;
        if (status != len) {
                status = -EREMOTEIO;
                goto free;
        }
        if (requesttype == 0x01)
                memcpy(pdata, pIo_buf, status);

regards,
dan carpenter