[PATCH v4 1/4] usb: renesas_usbhs: gadget: fix NULL pointer dereference in ep_disable()

[PATCH v4 1/4] usb: renesas_usbhs: gadget: fix NULL pointer dereference in ep_disable()

[Yoshihiro Shimoda]

From: Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>

This patch fixes an issue that the NULL pointer dereference happens
when we uses 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>
Cc: <stable@vger.kernel.org>
---
 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 2d17c10..294d43c 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 (!pipe)
+		return -EINVAL;
+
 	usbhsg_pipe_disable(uep);
 	usbhs_pipe_free(pipe);
 
-- 
1.7.9.5

Re: [PATCH v4 1/4] usb: renesas_usbhs: gadget: fix NULL pointer dereference in ep_disable()

[Felipe Balbi]

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On Fri, Oct 31, 2014 at 10:24:21AM +0900, Yoshihiro Shimoda wrote:
> From: Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>
> 
> This patch fixes an issue that the NULL pointer dereference happens
> when we uses 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>
> Cc: <stable@vger.kernel.org>

which commit caused this ? You need something like:

Fixes: deadbeef (commit subject line)
Cc: <stable@vger.kernel.org> # v3.14+

So stable folks know how far back this needs to be backported to.

-- 
balbi

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RE: [PATCH v4 1/4] usb: renesas_usbhs: gadget: fix NULL pointer dereference in ep_disable()

[yoshihiro shimoda]

> On Fri, Oct 31, 2014 at 10:24:21AM +0900, Yoshihiro Shimoda wrote:
> > From: Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>
> >
> > This patch fixes an issue that the NULL pointer dereference happens
> > when we uses 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>
> > Cc: <stable@vger.kernel.org>
> 
> which commit caused this ? You need something like:
> 
> Fixes: deadbeef (commit subject line)
> Cc: <stable@vger.kernel.org> # v3.14+
> 
> So stable folks know how far back this needs to be backported to.

Thank you for the point. I will add them.

Best regards,
Yoshihiro Shimoda