On Mon, Aug 05, 2013 at 06:40:12PM +0100, Rupesh Gujare wrote:
> This patch fixes kernel crash issue, when we receive URB request
> after de-enumerating device.
>
In other words we were getting a NULL dereference dereferencing
"ep". There is an existing check already, which should be cleaned
up.
drivers/staging/ozwpan/ozhcd.c
498
499 if (ep && port->hpd) {
^^
This useless existing check should be removed.
500 list_add_tail(&urbl->link, &ep->urb_list);
501 if (!in_dir && ep_addr && (ep->credit < 0)) {
502 getrawmonotonic(&ep->timestamp);
503 ep->credit = 0;
504 }
505 } else {
506 err = -EPIPE;
507 }
I'm not sure that think -ENOMEM is the correct error code but I
also don't know what else to use.
I had a style nit pick as well, below.
> Signed-off-by: Rupesh Gujare <rupesh.gujare@xxxxxxxxx>
> ---
> drivers/staging/ozwpan/ozhcd.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/ozwpan/ozhcd.c b/drivers/staging/ozwpan/ozhcd.c
> index ed63868..d313a63 100644
> --- a/drivers/staging/ozwpan/ozhcd.c
> +++ b/drivers/staging/ozwpan/ozhcd.c
> @@ -480,10 +480,14 @@ static int oz_enqueue_ep_urb(struct oz_port *port, u8 ep_addr, int in_dir,
> oz_free_urb_link(urbl);
> return 0;
> }
> - if (in_dir)
> + if (in_dir && port->in_ep[ep_addr])
> ep = port->in_ep[ep_addr];
> - else
> + else if (!in_dir && port->out_ep[ep_addr])
> ep = port->out_ep[ep_addr];
In the future, use kernel braces style. If one side of the if else
statement gets a brace then they both get one. So it's like this:
if (in_dir && port->in_ep[ep_addr]) {
ep = port->in_ep[ep_addr];
} else if (!in_dir && port->out_ep[ep_addr]) {
ep = port->out_ep[ep_addr];
} else {
err = -ENOMEM;
goto out;
}
Or another simpler way to write this would be:
ep = NULL;
if (in_dir)
ep = port->in_ep[ep_addr];
else
ep = port->out_ep[ep_addr];
if (!ep) {
err = -ENOMEM;
goto unlock;
}
regards,
dan carpenter
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