| Message ID | 20220824193813.13129-1-khalid.masum.92@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | d27c66adb4c0b16c817f71ba96e90f322e7419af |
| Headers | show |
| Series | [v2] usb: ehci: Use endpoint in URB to get maxpacket | expand |
On Thu, Aug 25, 2022 at 01:38:13AM +0600, Khalid Masum wrote: > usb_maxpacket() looks up the endpoint number in the pipe which can fail > if the interface or configuration changes before the routine is called. > This is unexpected and may even cause a modulo by zero afterwards. > > So use usb_endpoint_maxp() routine which uses the endpoint stored in URB > to get the maxpacket. > > Addresses-Coverity: 744857 ("Division or modulo by zero") > Addresses-Coverity: 1487371 ("Division or modulo by zero") > Suggested-by: Alan Stern <stern@rowland.harvard.edu> > Signed-off-by: Khalid Masum <khalid.masum.92@gmail.com> > --- > Changes since v1: > - Update commit description > - Use usb_endpoint_maxp() instead of checking whether getting maxpacket > failed > - Link: https://lore.kernel.org/lkml/20220823182758.13401-1-khalid.masum.92@gmail.com/ > > drivers/usb/host/ehci-q.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c > index 807e64991e3e..666f5c4db25a 100644 > --- a/drivers/usb/host/ehci-q.c > +++ b/drivers/usb/host/ehci-q.c > @@ -645,7 +645,7 @@ qh_urb_transaction ( > token |= (1 /* "in" */ << 8); > /* else it's already initted to "out" pid (0 << 8) */ > > - maxpacket = usb_maxpacket(urb->dev, urb->pipe); > + maxpacket = usb_endpoint_maxp(&urb->ep->desc); > > /* > * buffer gets wrapped in one or more qtds; > @@ -1218,7 +1218,7 @@ static int ehci_submit_single_step_set_feature( > > token |= (1 /* "in" */ << 8); /*This is IN stage*/ > > - maxpacket = usb_maxpacket(urb->dev, urb->pipe); > + maxpacket = usb_endpoint_maxp(&urb->ep->desc); > > qtd_fill(ehci, qtd, buf, len, token, maxpacket); Acked-by: Alan Stern <stern@rowland.harvard.edu>
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c index 807e64991e3e..666f5c4db25a 100644 --- a/drivers/usb/host/ehci-q.c +++ b/drivers/usb/host/ehci-q.c @@ -645,7 +645,7 @@ qh_urb_transaction ( token |= (1 /* "in" */ << 8); /* else it's already initted to "out" pid (0 << 8) */ - maxpacket = usb_maxpacket(urb->dev, urb->pipe); + maxpacket = usb_endpoint_maxp(&urb->ep->desc); /* * buffer gets wrapped in one or more qtds; @@ -1218,7 +1218,7 @@ static int ehci_submit_single_step_set_feature( token |= (1 /* "in" */ << 8); /*This is IN stage*/ - maxpacket = usb_maxpacket(urb->dev, urb->pipe); + maxpacket = usb_endpoint_maxp(&urb->ep->desc); qtd_fill(ehci, qtd, buf, len, token, maxpacket);
usb_maxpacket() looks up the endpoint number in the pipe which can fail if the interface or configuration changes before the routine is called. This is unexpected and may even cause a modulo by zero afterwards. So use usb_endpoint_maxp() routine which uses the endpoint stored in URB to get the maxpacket. Addresses-Coverity: 744857 ("Division or modulo by zero") Addresses-Coverity: 1487371 ("Division or modulo by zero") Suggested-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Khalid Masum <khalid.masum.92@gmail.com> --- Changes since v1: - Update commit description - Use usb_endpoint_maxp() instead of checking whether getting maxpacket failed - Link: https://lore.kernel.org/lkml/20220823182758.13401-1-khalid.masum.92@gmail.com/ drivers/usb/host/ehci-q.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)