* [PATCH] drivers: usb: gadget: udc: Fix NULL dereference
@ 2015-03-03 12:58 Tapasweni Pathak
2015-03-04 1:11 ` Peter Chen
0 siblings, 1 reply; 7+ messages in thread
From: Tapasweni Pathak @ 2015-03-03 12:58 UTC (permalink / raw)
To: balbi, gregkh, peter.chen, jg1.han, benoit.taine, linux-usb,
linux-kernel
Cc: julia.lawall, tapaswenipathak
This patch fixes multiple instances of null pointer dereference in this code.
ep->udc is assigned to udc. ep is just an offset from _ep. _ep is then
checked for NULL. udc is dereferenced under the NULL check for _ep, making
an invalid pointer reference.
udc is then checked for NULL, if NULL, it is then dereferenced as
udc->dev.
To fix these issues, shift assignment of udc by dereferencing ep after
null check for _ep, replace both dev_dbg statements with pr_debug.
Found using Coccinelle.
Signed-off-by: Tapasweni Pathak <tapaswenipathak@gmail.com>
Suggested-by : Julia Lawall <julia.lawall@lip6.fr>
Reviewed-by : Julia Lawall <julia.lawall@lip6.fr>
---
drivers/usb/gadget/udc/lpc32xx_udc.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/usb/gadget/udc/lpc32xx_udc.c b/drivers/usb/gadget/udc/lpc32xx_udc.c
index 27fd413..6398539 100644
--- a/drivers/usb/gadget/udc/lpc32xx_udc.c
+++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
@@ -1807,17 +1807,16 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
!list_empty(&req->queue))
return -EINVAL;
- udc = ep->udc;
-
if (!_ep) {
- dev_dbg(udc->dev, "invalid ep\n");
+ pr_debug("invalid ep\n");
return -EINVAL;
}
+ udc = ep->udc;
if ((!udc) || (!udc->driver) ||
(udc->gadget.speed == USB_SPEED_UNKNOWN)) {
- dev_dbg(udc->dev, "invalid device\n");
+ pr_debug("invalid device\n");
return -EINVAL;
}
--
1.7.9.5
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH] drivers: usb: gadget: udc: Fix NULL dereference
2015-03-03 12:58 [PATCH] drivers: usb: gadget: udc: Fix NULL dereference Tapasweni Pathak
@ 2015-03-04 1:11 ` Peter Chen
2015-03-09 15:41 ` Felipe Balbi
0 siblings, 1 reply; 7+ messages in thread
From: Peter Chen @ 2015-03-04 1:11 UTC (permalink / raw)
To: Tapasweni Pathak
Cc: balbi, gregkh, jg1.han, benoit.taine, linux-usb, linux-kernel,
julia.lawall
On Tue, Mar 03, 2015 at 06:28:42PM +0530, Tapasweni Pathak wrote:
> This patch fixes multiple instances of null pointer dereference in this code.
>
> ep->udc is assigned to udc. ep is just an offset from _ep. _ep is then
> checked for NULL. udc is dereferenced under the NULL check for _ep, making
> an invalid pointer reference.
>
> udc is then checked for NULL, if NULL, it is then dereferenced as
> udc->dev.
>
> To fix these issues, shift assignment of udc by dereferencing ep after
> null check for _ep, replace both dev_dbg statements with pr_debug.
>
> Found using Coccinelle.
>
> Signed-off-by: Tapasweni Pathak <tapaswenipathak@gmail.com>
> Suggested-by : Julia Lawall <julia.lawall@lip6.fr>
> Reviewed-by : Julia Lawall <julia.lawall@lip6.fr>
> ---
> drivers/usb/gadget/udc/lpc32xx_udc.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/gadget/udc/lpc32xx_udc.c b/drivers/usb/gadget/udc/lpc32xx_udc.c
> index 27fd413..6398539 100644
> --- a/drivers/usb/gadget/udc/lpc32xx_udc.c
> +++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
> @@ -1807,17 +1807,16 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> !list_empty(&req->queue))
> return -EINVAL;
>
> - udc = ep->udc;
> -
> if (!_ep) {
> - dev_dbg(udc->dev, "invalid ep\n");
> + pr_debug("invalid ep\n");
> return -EINVAL;
> }
>
> + udc = ep->udc;
>
> if ((!udc) || (!udc->driver) ||
> (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
> - dev_dbg(udc->dev, "invalid device\n");
> + pr_debug("invalid device\n");
> return -EINVAL;
> }
>
It is driver code, we'd better use dev_dbg. If _ep exists,
both ep and udc should exist. So, how about just checking
_ep at the beginning:
diff --git a/drivers/usb/gadget/udc/lpc32xx_udc.c b/drivers/usb/gadget/udc/lpc32xx_udc.c
index 27fd413..c65de0e 100644
--- a/drivers/usb/gadget/udc/lpc32xx_udc.c
+++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
@@ -1803,7 +1803,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
req = container_of(_req, struct lpc32xx_request, req);
ep = container_of(_ep, struct lpc32xx_ep, ep);
- if (!_req || !_req->complete || !_req->buf ||
+ if (!_ep || !_req || !_req->complete || !_req->buf ||
!list_empty(&req->queue))
return -EINVAL;
@@ -1815,8 +1815,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
}
- if ((!udc) || (!udc->driver) ||
- (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
+ if ((!udc->driver) || (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
dev_dbg(udc->dev, "invalid device\n");
return -EINVAL;
}
--
Best Regards,
Peter Chen
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH] drivers: usb: gadget: udc: Fix NULL dereference
2015-03-04 1:11 ` Peter Chen
@ 2015-03-09 15:41 ` Felipe Balbi
2015-03-10 2:02 ` Peter Chen
0 siblings, 1 reply; 7+ messages in thread
From: Felipe Balbi @ 2015-03-09 15:41 UTC (permalink / raw)
To: Peter Chen
Cc: Tapasweni Pathak, balbi, gregkh, jg1.han, benoit.taine,
linux-usb, linux-kernel, julia.lawall
[-- Attachment #1: Type: text/plain, Size: 2886 bytes --]
On Wed, Mar 04, 2015 at 09:11:19AM +0800, Peter Chen wrote:
> On Tue, Mar 03, 2015 at 06:28:42PM +0530, Tapasweni Pathak wrote:
> > This patch fixes multiple instances of null pointer dereference in this code.
> >
> > ep->udc is assigned to udc. ep is just an offset from _ep. _ep is then
> > checked for NULL. udc is dereferenced under the NULL check for _ep, making
> > an invalid pointer reference.
> >
> > udc is then checked for NULL, if NULL, it is then dereferenced as
> > udc->dev.
> >
> > To fix these issues, shift assignment of udc by dereferencing ep after
> > null check for _ep, replace both dev_dbg statements with pr_debug.
> >
> > Found using Coccinelle.
> >
> > Signed-off-by: Tapasweni Pathak <tapaswenipathak@gmail.com>
> > Suggested-by : Julia Lawall <julia.lawall@lip6.fr>
> > Reviewed-by : Julia Lawall <julia.lawall@lip6.fr>
> > ---
> > drivers/usb/gadget/udc/lpc32xx_udc.c | 7 +++----
> > 1 file changed, 3 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/usb/gadget/udc/lpc32xx_udc.c b/drivers/usb/gadget/udc/lpc32xx_udc.c
> > index 27fd413..6398539 100644
> > --- a/drivers/usb/gadget/udc/lpc32xx_udc.c
> > +++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
> > @@ -1807,17 +1807,16 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > !list_empty(&req->queue))
> > return -EINVAL;
> >
> > - udc = ep->udc;
> > -
> > if (!_ep) {
> > - dev_dbg(udc->dev, "invalid ep\n");
> > + pr_debug("invalid ep\n");
> > return -EINVAL;
> > }
> >
> > + udc = ep->udc;
> >
> > if ((!udc) || (!udc->driver) ||
> > (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
> > - dev_dbg(udc->dev, "invalid device\n");
> > + pr_debug("invalid device\n");
> > return -EINVAL;
> > }
> >
>
> It is driver code, we'd better use dev_dbg. If _ep exists,
> both ep and udc should exist. So, how about just checking
> _ep at the beginning:
>
> diff --git a/drivers/usb/gadget/udc/lpc32xx_udc.c b/drivers/usb/gadget/udc/lpc32xx_udc.c
> index 27fd413..c65de0e 100644
> --- a/drivers/usb/gadget/udc/lpc32xx_udc.c
> +++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
> @@ -1803,7 +1803,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> req = container_of(_req, struct lpc32xx_request, req);
> ep = container_of(_ep, struct lpc32xx_ep, ep);
>
> - if (!_req || !_req->complete || !_req->buf ||
> + if (!_ep || !_req || !_req->complete || !_req->buf ||
> !list_empty(&req->queue))
> return -EINVAL;
>
> @@ -1815,8 +1815,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> }
>
>
> - if ((!udc) || (!udc->driver) ||
> - (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
> + if ((!udc->driver) || (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
> dev_dbg(udc->dev, "invalid device\n");
> return -EINVAL;
> }
what's going to happen here ?
--
balbi
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^ permalink raw reply [flat|nested] 7+ messages in thread
* RE: [PATCH] drivers: usb: gadget: udc: Fix NULL dereference
2015-03-09 15:41 ` Felipe Balbi
@ 2015-03-10 2:02 ` Peter Chen
2015-03-10 2:36 ` Felipe Balbi
0 siblings, 1 reply; 7+ messages in thread
From: Peter Chen @ 2015-03-10 2:02 UTC (permalink / raw)
To: balbi
Cc: Tapasweni Pathak, gregkh, jg1.han, benoit.taine, linux-usb,
linux-kernel, julia.lawall
> > --- a/drivers/usb/gadget/udc/lpc32xx_udc.c
> > +++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
> > @@ -1803,7 +1803,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > req = container_of(_req, struct lpc32xx_request, req);
> > ep = container_of(_ep, struct lpc32xx_ep, ep);
> >
> > - if (!_req || !_req->complete || !_req->buf ||
> > + if (!_ep || !_req || !_req->complete || !_req->buf ||
> > !list_empty(&req->queue))
> > return -EINVAL;
> >
> > @@ -1815,8 +1815,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > }
> >
> >
> > - if ((!udc) || (!udc->driver) ||
> > - (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
> > + if ((!udc->driver) || (udc->gadget.speed == USB_SPEED_UNKNOWN))
> {
> > dev_dbg(udc->dev, "invalid device\n");
> > return -EINVAL;
> > }
>
> what's going to happen here ?
>
I just changed the current code, in fact, udc->driver is impossible to NULL which
is cleared at .udc_stop.
The speed is possible for unknown if the reset has occurred at that time.
Peter
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] drivers: usb: gadget: udc: Fix NULL dereference
2015-03-10 2:02 ` Peter Chen
@ 2015-03-10 2:36 ` Felipe Balbi
2015-03-10 3:00 ` Peter Chen
0 siblings, 1 reply; 7+ messages in thread
From: Felipe Balbi @ 2015-03-10 2:36 UTC (permalink / raw)
To: Peter Chen
Cc: balbi, Tapasweni Pathak, gregkh, jg1.han, benoit.taine,
linux-usb, linux-kernel, julia.lawall
[-- Attachment #1: Type: text/plain, Size: 1202 bytes --]
On Tue, Mar 10, 2015 at 02:02:44AM +0000, Peter Chen wrote:
>
> > > --- a/drivers/usb/gadget/udc/lpc32xx_udc.c
> > > +++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
> > > @@ -1803,7 +1803,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > > req = container_of(_req, struct lpc32xx_request, req);
> > > ep = container_of(_ep, struct lpc32xx_ep, ep);
> > >
> > > - if (!_req || !_req->complete || !_req->buf ||
> > > + if (!_ep || !_req || !_req->complete || !_req->buf ||
> > > !list_empty(&req->queue))
> > > return -EINVAL;
> > >
> > > @@ -1815,8 +1815,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > > }
> > >
> > >
> > > - if ((!udc) || (!udc->driver) ||
> > > - (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
> > > + if ((!udc->driver) || (udc->gadget.speed == USB_SPEED_UNKNOWN))
> > {
> > > dev_dbg(udc->dev, "invalid device\n");
> > > return -EINVAL;
> > > }
> >
> > what's going to happen here ?
> >
>
> I just changed the current code, in fact, udc->driver is impossible to NULL which
> is cleared at .udc_stop.
>
> The speed is possible for unknown if the reset has occurred at that time.
oh, alright.
--
balbi
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^ permalink raw reply [flat|nested] 7+ messages in thread
* RE: [PATCH] drivers: usb: gadget: udc: Fix NULL dereference
2015-03-10 2:36 ` Felipe Balbi
@ 2015-03-10 3:00 ` Peter Chen
2015-03-10 20:50 ` Felipe Balbi
0 siblings, 1 reply; 7+ messages in thread
From: Peter Chen @ 2015-03-10 3:00 UTC (permalink / raw)
To: balbi
Cc: Tapasweni Pathak, gregkh, jg1.han, benoit.taine, linux-usb,
linux-kernel, julia.lawall
> On Tue, Mar 10, 2015 at 02:02:44AM +0000, Peter Chen wrote:
> >
> > > > --- a/drivers/usb/gadget/udc/lpc32xx_udc.c
> > > > +++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
> > > > @@ -1803,7 +1803,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > > > req = container_of(_req, struct lpc32xx_request, req);
> > > > ep = container_of(_ep, struct lpc32xx_ep, ep);
> > > >
> > > > - if (!_req || !_req->complete || !_req->buf ||
> > > > + if (!_ep || !_req || !_req->complete || !_req->buf ||
> > > > !list_empty(&req->queue))
> > > > return -EINVAL;
> > > >
> > > > @@ -1815,8 +1815,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > > > }
> > > >
> > > >
> > > > - if ((!udc) || (!udc->driver) ||
> > > > - (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
> > > > + if ((!udc->driver) || (udc->gadget.speed == USB_SPEED_UNKNOWN))
> > > {
> > > > dev_dbg(udc->dev, "invalid device\n");
> > > > return -EINVAL;
> > > > }
> > >
> > > what's going to happen here ?
> > >
> >
> > I just changed the current code, in fact, udc->driver is impossible to
> > NULL which is cleared at .udc_stop.
> >
> > The speed is possible for unknown if the reset has occurred at that time.
>
> oh, alright.
Do you need me or Tapasweni send patch for this?
Peter
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH] drivers: usb: gadget: udc: Fix NULL dereference
2015-03-10 3:00 ` Peter Chen
@ 2015-03-10 20:50 ` Felipe Balbi
0 siblings, 0 replies; 7+ messages in thread
From: Felipe Balbi @ 2015-03-10 20:50 UTC (permalink / raw)
To: Peter Chen
Cc: balbi, Tapasweni Pathak, gregkh, jg1.han, benoit.taine,
linux-usb, linux-kernel, julia.lawall
[-- Attachment #1: Type: text/plain, Size: 1495 bytes --]
On Tue, Mar 10, 2015 at 03:00:49AM +0000, Peter Chen wrote:
>
> > On Tue, Mar 10, 2015 at 02:02:44AM +0000, Peter Chen wrote:
> > >
> > > > > --- a/drivers/usb/gadget/udc/lpc32xx_udc.c
> > > > > +++ b/drivers/usb/gadget/udc/lpc32xx_udc.c
> > > > > @@ -1803,7 +1803,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > > > > req = container_of(_req, struct lpc32xx_request, req);
> > > > > ep = container_of(_ep, struct lpc32xx_ep, ep);
> > > > >
> > > > > - if (!_req || !_req->complete || !_req->buf ||
> > > > > + if (!_ep || !_req || !_req->complete || !_req->buf ||
> > > > > !list_empty(&req->queue))
> > > > > return -EINVAL;
> > > > >
> > > > > @@ -1815,8 +1815,7 @@ static int lpc32xx_ep_queue(struct usb_ep *_ep,
> > > > > }
> > > > >
> > > > >
> > > > > - if ((!udc) || (!udc->driver) ||
> > > > > - (udc->gadget.speed == USB_SPEED_UNKNOWN)) {
> > > > > + if ((!udc->driver) || (udc->gadget.speed == USB_SPEED_UNKNOWN))
> > > > {
> > > > > dev_dbg(udc->dev, "invalid device\n");
> > > > > return -EINVAL;
> > > > > }
> > > >
> > > > what's going to happen here ?
> > > >
> > >
> > > I just changed the current code, in fact, udc->driver is impossible to
> > > NULL which is cleared at .udc_stop.
> > >
> > > The speed is possible for unknown if the reset has occurred at that time.
> >
> > oh, alright.
>
> Do you need me or Tapasweni send patch for this?
if there's anything to be fixed, sure.
--
balbi
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^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2015-03-10 20:51 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-03-03 12:58 [PATCH] drivers: usb: gadget: udc: Fix NULL dereference Tapasweni Pathak
2015-03-04 1:11 ` Peter Chen
2015-03-09 15:41 ` Felipe Balbi
2015-03-10 2:02 ` Peter Chen
2015-03-10 2:36 ` Felipe Balbi
2015-03-10 3:00 ` Peter Chen
2015-03-10 20:50 ` Felipe Balbi
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