[PATCH 1/4] usb: renesas_usbhs: gadget: fix NULL pointer dereference in ep_disable()

[PATCH 1/4] usb: renesas_usbhs: gadget: fix NULL pointer dereference in ep_disable()

[Yoshihiro Shimoda]

This patch fixes an issue that the NULL pointer dereference happens
when we use g_audio driver. Since the g_audio driver will call
usb_ep_disable() in afunc_set_alt() before it calls usb_ep_enable(),
the uep->pipe of renesas usbhs driver will be NULL. So, this patch
adds a condition to avoid the oops.

Signed-off-by: Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>
Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
---
 drivers/usb/renesas_usbhs/mod_gadget.c |    3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/renesas_usbhs/mod_gadget.c b/drivers/usb/renesas_usbhs/mod_gadget.c
index 04e6505..a582222 100644
--- a/drivers/usb/renesas_usbhs/mod_gadget.c
+++ b/drivers/usb/renesas_usbhs/mod_gadget.c
@@ -602,6 +602,9 @@ static int usbhsg_ep_disable(struct usb_ep *ep)
 	struct usbhsg_uep *uep = usbhsg_ep_to_uep(ep);
 	struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);

+	if (!uep || !uep->pipe)
+		return -EINVAL;
+
 	usbhsg_pipe_disable(uep);
 	usbhs_pipe_free(pipe);

-- 
1.7.9.5

Re: [PATCH 1/4] usb: renesas_usbhs: gadget: fix NULL pointer dereference in ep_disable()

[Felipe Balbi]

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On Wed, Sep 10, 2014 at 07:33:40PM +0900, Yoshihiro Shimoda wrote:
> This patch fixes an issue that the NULL pointer dereference happens
> when we use g_audio driver. Since the g_audio driver will call
> usb_ep_disable() in afunc_set_alt() before it calls usb_ep_enable(),
> the uep->pipe of renesas usbhs driver will be NULL. So, this patch
> adds a condition to avoid the oops.
> 
> Signed-off-by: Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>
> Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

Which commit does this fix ? Do we need a Cc: stable ?

-- 
balbi

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Re: [PATCH 1/4] usb: renesas_usbhs: gadget: fix NULL pointer dereference in ep_disable()

[Kuninori Morimoto]

Hi Shimoda-san

> --- a/drivers/usb/renesas_usbhs/mod_gadget.c
> +++ b/drivers/usb/renesas_usbhs/mod_gadget.c
> @@ -602,6 +602,9 @@ static int usbhsg_ep_disable(struct usb_ep *ep)
>  	struct usbhsg_uep *uep = usbhsg_ep_to_uep(ep);
>  	struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);
> 
> +	if (!uep || !uep->pipe)
> +		return -EINVAL;
> +
>  	usbhsg_pipe_disable(uep);
>  	usbhs_pipe_free(pipe);

If uep can be NULL,
we need care about usbhsg_uep_to_pipe(uep) too.

and, "uep->pipe" is same as "pipe" ?

Best regards
---
Kuninori Morimoto

Re: [PATCH 1/4] usb: renesas_usbhs: gadget: fix NULL pointer dereference in ep_disable()

[Yoshihiro Shimoda]

Hi,

(2014/09/10 22:49), Felipe Balbi wrote:
> On Wed, Sep 10, 2014 at 07:33:40PM +0900, Yoshihiro Shimoda wrote:
>> This patch fixes an issue that the NULL pointer dereference happens
>> when we use g_audio driver. Since the g_audio driver will call
>> usb_ep_disable() in afunc_set_alt() before it calls usb_ep_enable(),
>> the uep->pipe of renesas usbhs driver will be NULL. So, this patch
>> adds a condition to avoid the oops.
>>
>> Signed-off-by: Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>
>> Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
>> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
> 
> Which commit does this fix ? Do we need a Cc: stable ?
> 

I think we need a Cc: stable in this patch because the previous code causes the oops.

Best regards,
Yoshihiro Shimoda

Re: [PATCH 1/4] usb: renesas_usbhs: gadget: fix NULL pointer dereference in ep_disable()

[Yoshihiro Shimoda]

Hi Morimoto-san,

(2014/09/11 8:56), Kuninori Morimoto wrote:
> 
> Hi Shimoda-san
> 
>> --- a/drivers/usb/renesas_usbhs/mod_gadget.c
>> +++ b/drivers/usb/renesas_usbhs/mod_gadget.c
>> @@ -602,6 +602,9 @@ static int usbhsg_ep_disable(struct usb_ep *ep)
>>  	struct usbhsg_uep *uep = usbhsg_ep_to_uep(ep);
>>  	struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);
>>
>> +	if (!uep || !uep->pipe)
>> +		return -EINVAL;
>> +
>>  	usbhsg_pipe_disable(uep);
>>  	usbhs_pipe_free(pipe);
> 
> If uep can be NULL,
> we need care about usbhsg_uep_to_pipe(uep) too.

Thank you for the point.
I will check the uep can be NULL or not.

> and, "uep->pipe" is same as "pipe" ?

Yes. I will use "pipe" instead of "uep->pipe".

Best regards,
Yoshihiro Shimoda

> Best regards
> ---
> Kuninori Morimoto
>