| Message ID | 1414665019-1340-2-git-send-email-yoshihiro.shimoda.uh@renesas.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
On Thu, Oct 30, 2014 at 07:30:16PM +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> > --- > 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..2d0903f 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) how can uep ever be NULL ? Look at the definition of usbhsg_ep_to_uep(): #define usbhsg_ep_to_uep(e) container_of(e, struct usbhsg_uep, ep) how can a container_of() ever return NULL ? What you should check if "ep" (the argument to this function) being NULL.
> On Thu, Oct 30, 2014 at 07:30:16PM +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> > > --- > > 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..2d0903f 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) > > how can uep ever be NULL ? Look at the definition of usbhsg_ep_to_uep(): > > #define usbhsg_ep_to_uep(e) container_of(e, struct usbhsg_uep, ep) > > how can a container_of() ever return NULL ? What you should check if "ep" (the argument to this function) being NULL. Thank you for the point. Morimoto-san also pointed out this code at v1 patch. But I forgot to fix it... We can change the "if (!uep || !uep->pipe)" to "if (!pipe)". I will fix this patch. Best regards, Yoshihiro Shimoda -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Oct 31, 2014 at 12:06:06AM +0000, yoshihiro shimoda wrote: > > On Thu, Oct 30, 2014 at 07:30:16PM +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> > > > --- > > > 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..2d0903f 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) > > > > how can uep ever be NULL ? Look at the definition of > > usbhsg_ep_to_uep(): > > > > #define usbhsg_ep_to_uep(e) container_of(e, struct usbhsg_uep, ep) > > > > how can a container_of() ever return NULL ? What you should check if > > "ep" (the argument to this function) being NULL. > > Thank you for the point. > Morimoto-san also pointed out this code at v1 patch. But I forgot to fix it... > We can change the "if (!uep || !uep->pipe)" to "if (!pipe)". alright, I'll wait for a new version. Thank you
diff --git a/drivers/usb/renesas_usbhs/mod_gadget.c b/drivers/usb/renesas_usbhs/mod_gadget.c index 2d17c10..2d0903f 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);