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Subject: Re: [usb-storage] usb: storage: suspicious code
From: Oliver Neukum <oneukum@suse.com>
To: "Gustavo A. R. Silva" <garsilva@embeddedor.com>,
        stern@rowland.harvard.edu, gregkh@linuxfoundation.org
Cc: linux-usb@vger.kernel.org, usb-storage@lists.one-eyed-alien.net,
        linux-kernel@vger.kernel.org,
        Peter Senna Tschudi <peter.senna@gmail.com>
Date: Wed, 15 Feb 2017 08:01:13 +0100
In-Reply-To: <20170215050652.GA6371@embeddedgus>
References: <20170215050652.GA6371@embeddedgus>
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Am Dienstag, den 14.02.2017, 23:06 -0600 schrieb Gustavo A. R. Silva:

Hi,

> waitcount = 0;
> do {
>         result = jumpshot_get_status(us);
>         if (result != USB_STOR_TRANSPORT_GOOD) {
>                 // I have not experimented to find the smallest
> value.
>                 //
>                 msleep(50);
>         }
>         } while ((result != USB_STOR_TRANSPORT_GOOD) && (waitcount <
> 10));
> 
>         if (result != USB_STOR_TRANSPORT_GOOD)
>                 usb_stor_dbg(us, "Gah!  Waitcount = 10.  Bad
> write!?\n");
> 
> Variable 'waitcount' is never updated inside the do-while loop. So,
> either it isn't needed at all or line 316 should be modified
> (++waitcount < 10)

you are correct. Waitcount needs to be incremented.

	HTH
		Oliver