[ofw] [IPoIB, IPoIB_CM] Bugfix for UDP packets

[Alex Estrin]

Thanks!
Applied in branch 'ipoib_cm' rev 1843.

Alex.

> -----Original Message-----
> From: Alex Naslednikov [mailto:xalex at mellanox.co.il] 
> Sent: Monday, January 19, 2009 11:00 AM
> To: Alex Estrin; ofw at lists.openfabrics.org
> Cc: Tzachi Dar
> Subject: RE: [ofw] [IPoIB, IPoIB_CM] Bugfix for UDP packets
> 
> Yes, I wrote about it in the bug description.
> Sorry if I wasn't clear.
> 
> The bug was exist always, for all kind of large UDP packets.
> But it was shown only for the packets that were fragmented in 
> such a way
> that the last fragmented packets was less than 8 bytes of data.
> The reason is that for the small packets (less than 8 bytes 
> of data) the
> following check failed:
> if( buf_len < sizeof(udp_hdr_t) )
> 	{
> 		IPOIB_PRINT_EXIT( TRACE_LEVEL_ERROR, IPOIB_DBG_ERROR,
> 			("Buffer not large enough for UDP packet.\n") );
> 		return NDIS_STATUS_BUFFER_TOO_SHORT;
> 	}
> 
> Size of udo_hdr_t is 8, so all other packets passed this checked and
> also returnrd NDIS_STATUS_PENDING on the next check:
> f( (p_udp_hdr->src_port != DHCP_PORT_CLIENT ||
>    p_udp_hdr->dst_port != DHCP_PORT_SERVER) &&
>    (p_udp_hdr->src_port != DHCP_PORT_SERVER ||
>    p_udp_hdr->dst_port != DHCP_PORT_CLIENT) )  {
>    /* Not a DHCP packet. */
>    return NDIS_STATUS_PENDING;
>   }
> 
> Of course, it was by mistake, because udp header doesn't exist for
> fragmented packets (except the first one)
> 
> XaleX
> 
> -----Original Message-----
> From: Alex Estrin [mailto:alex.estrin at qlogic.com] 
> Sent: Monday, January 19, 2009 5:06 PM
> To: Alex Naslednikov; ofw at lists.openfabrics.org
> Cc: Tzachi Dar
> Subject: RE: [ofw] [IPoIB, IPoIB_CM] Bugfix for UDP packets
> 
> Hello,
> 
> Would you please clarify if this is the case when OS fragments large
> send packet to interface-MTU-size chunks?
> 
> Thanks,
> Alex.
> 
> 
> > -----Original Message-----
> > From: Alex Naslednikov [mailto:xalex at mellanox.co.il]
> > Sent: Sunday, January 18, 2009 9:37 AM
> > To: ofw at lists.openfabrics.org
> > Cc: Tzachi Dar; Alex Estrin
> > Subject: [ofw] [IPoIB, IPoIB_CM] Bugfix for UDP packets
> > 
> > Several test were failed on sending UDP packets with MTU-like sizes.
> > Fragmented UDP packets do not contain UDP header, except the first 
> > one.
> > So, appropriate check was inserted.
> >  
> > This bug was shown rarely (only when the last fragment was 
> less than 8
> 
> > bytes), because the following check always worked (by mistake):
> >  
> > if( (p_udp_hdr->src_port != DHCP_PORT_CLIENT ||
> >   p_udp_hdr->dst_port != DHCP_PORT_SERVER) &&
> >   (p_udp_hdr->src_port != DHCP_PORT_SERVER ||
> >   p_udp_hdr->dst_port != DHCP_PORT_CLIENT) )  {
> >   /* Not a DHCP packet. */
> >   return NDIS_STATUS_PENDING;
> >  }
> >  
> > Index: ipoib_port.c
> > ===================================================================
> > --- ipoib_port.c (revision 3752)
> > +++ ipoib_port.c (working copy)
> > @@ -3763,6 +3763,15 @@
> >    p_udp_hdr = (udp_hdr_t*)GetIpPayloadPtr(p_ip_hdr);
> >   }
> >   /* Get the UDP header and check the destination port numbers. */
> > + 
> > + if (p_ip_hdr->offset > 0) {
> > +  /* This is a fragmented part of UDP packet
> > +   * Only first packet will contain UDP header in such case
> > +   * So, return if offset > 0
> > +   */
> > +   return NDIS_STATUS_PENDING;
> > + }
> > +   
> >   if( buf_len < sizeof(udp_hdr_t) )
> >   {
> >    IPOIB_PRINT_EXIT( TRACE_LEVEL_ERROR, IPOIB_DBG_ERROR
> > 
>