* [PATCH v2 1/1] usb: musb: gadget: misplaced out of bounds check
@ 2018-03-20 2:27 Heinrich Schuchardt
2018-03-20 9:36 ` Sergei Shtylyov
0 siblings, 1 reply; 2+ messages in thread
From: Heinrich Schuchardt @ 2018-03-20 2:27 UTC (permalink / raw)
To: Bin Liu; +Cc: Greg Kroah-Hartman, linux-usb, linux-kernel, Heinrich Schuchardt
musb->endpoints[] has array size MUSB_C_NUM_EPS.
We must check array bounds before accessing the array and not afterwards.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
---
v2
Only the 4 low bits of epnum are relevant for indexing.
---
drivers/usb/musb/musb_gadget_ep0.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/musb/musb_gadget_ep0.c b/drivers/usb/musb/musb_gadget_ep0.c
index 18da4873e52e..96b0fa12f729 100644
--- a/drivers/usb/musb/musb_gadget_ep0.c
+++ b/drivers/usb/musb/musb_gadget_ep0.c
@@ -89,15 +89,20 @@ static int service_tx_status_request(
}
is_in = epnum & USB_DIR_IN;
+ epnum &= 0x0f;
+ if (epnum >= MUSB_C_NUM_EPS) {
+ handled = -EINVAL;
+ break;
+ }
+
if (is_in) {
- epnum &= 0x0f;
ep = &musb->endpoints[epnum].ep_in;
} else {
ep = &musb->endpoints[epnum].ep_out;
}
regs = musb->endpoints[epnum].regs;
- if (epnum >= MUSB_C_NUM_EPS || !ep->desc) {
+ if (!ep->desc) {
handled = -EINVAL;
break;
}
--
2.16.2
^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH v2 1/1] usb: musb: gadget: misplaced out of bounds check
2018-03-20 2:27 [PATCH v2 1/1] usb: musb: gadget: misplaced out of bounds check Heinrich Schuchardt
@ 2018-03-20 9:36 ` Sergei Shtylyov
0 siblings, 0 replies; 2+ messages in thread
From: Sergei Shtylyov @ 2018-03-20 9:36 UTC (permalink / raw)
To: Heinrich Schuchardt, Bin Liu; +Cc: Greg Kroah-Hartman, linux-usb, linux-kernel
Hello!
On 3/20/2018 5:27 AM, Heinrich Schuchardt wrote:
> musb->endpoints[] has array size MUSB_C_NUM_EPS.
> We must check array bounds before accessing the array and not afterwards.
>
> Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
> ---
> v2
> Only the 4 low bits of epnum are relevant for indexing.
> ---
> drivers/usb/musb/musb_gadget_ep0.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/musb/musb_gadget_ep0.c b/drivers/usb/musb/musb_gadget_ep0.c
> index 18da4873e52e..96b0fa12f729 100644
> --- a/drivers/usb/musb/musb_gadget_ep0.c
> +++ b/drivers/usb/musb/musb_gadget_ep0.c
> @@ -89,15 +89,20 @@ static int service_tx_status_request(
> }
>
> is_in = epnum & USB_DIR_IN;
> + epnum &= 0x0f;
> + if (epnum >= MUSB_C_NUM_EPS) {
> + handled = -EINVAL;
> + break;
> + }
> +
> if (is_in) {
> - epnum &= 0x0f;
> ep = &musb->endpoints[epnum].ep_in;
> } else {
> ep = &musb->endpoints[epnum].ep_out;
> }
Please remove the braces, they're not needed anymore.
[...]
MBR, Sergei
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2018-03-20 9:36 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-03-20 2:27 [PATCH v2 1/1] usb: musb: gadget: misplaced out of bounds check Heinrich Schuchardt
2018-03-20 9:36 ` Sergei Shtylyov
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).