[ofw] [PATCH] ipoib_ndis6_cm - prevent UD IPoIB from falsely advertizing a Connect Mode capability.

[Smith, Stan]

Alex Naslednikov wrote:
> Oh...please, commit !
> But in the future, when CM mode will be released, the code should be
> like:
> ipoib_addr_set_flags( &p_ib_arp->src_hw,
> p_port->p_adapter->params.cm_enabled ? IPOIB_CM_FLAG_RC : 0 );

Will commit ASAP.
Agreed on the ipoib_addr_set_flags() call in the CM future.

thanks,

stan.

>
> -----Original Message-----
> From: Smith, Stan [mailto:stan.smith at intel.com]
> Sent: Monday, September 13, 2010 10:47 PM
> To: Alex Naslednikov
> Cc: ofw at lists.openfabrics.org
> Subject: [PATCH] ipoib_ndis6_cm - prevent UD IPoIB from falsely
> advertizing a Connect Mode capability.
>
>
> Hello,
>   Here is a curious bug for your inspection.
> In the case where a UD [non-CM (Connected Mode)] IPoIB receives an
> ARP Request from a CM enabled IPoIB, the UD IPoIB can falsely
> advertise a CM (Connect Mode) capability in the ARP Reply src
> hardware address due to an uninitialized CM flags field.
> The ARP reply packet is constructed from a send_buf_list allocated
> buffer. The cm field byte of the src hardware address in the ARP
> Request never gets initialized, hence the IPoIB UD ARP reply can
> falsely advertise a CM capability depending on the value of the CM
> capability byte; turns out 1 is a somewhat common memory value. :-)
> It's not a problem for UD IPoIB talking to another UD IPoIB; CM flags
> are ignored. OFED/Linux CM IPoIB would attempt to RC connect which
> would fail.
>
> The fix is to always set the CM capabilities byte of the ARP Reply
> src hardware address.flags_qpn field with the current IPoIB CM
> capability byte.
>
> signed-off-by: stan smith <stan.smith at intel.com>
>
> --- a/ulp/ipoib_NDIS6_CM/kernel/ipoib_port.cpp  Mon Sep 13 13:08:48
> 2010 +++ b/ulp/ipoib_NDIS6_CM/kernel/ipoib_port.cpp  Mon Sep 13
> 11:18:39 2010 @@ -4891,6 +4891,7 @@
>         p_ib_arp->op = p_arp->op;
>
>         ipoib_addr_set_qpn( &p_ib_arp->src_hw,
> s_buf->p_port->ib_mgr.qpn ); +       ipoib_addr_set_flags(
>  &p_ib_arp->src_hw, 0 ); #if 0
>
>         if( p_port->p_adapter->params.cm_enabled )