[U-Boot] [PATCH 22/28] net: Fix net buffer initialization

[Joe Hershberger]

Hi Mike,

On Fri, Feb 3, 2012 at 6:37 AM, Mike Frysinger <vapier at gentoo.org> wrote:
> On Thursday 19 January 2012 19:53:25 Joe Hershberger wrote:
>> @@ -627,6 +639,12 @@ NetSendUDPPacket
>>
>> +     /* make sure the NetTxPacket is initialized (NetInit() was called) */
>> +     if (NetTxPacket == NULL) {
>> +             puts("*** ERROR: NetTxPacket buffer pointer is NULL!\n");
>> +             return -1;
>> +     }
>
> why check here only (udp) ?  and why check at all ?  this should be an
> assert() in the comment netsendpacket entry point ...

This is specifically needed here because the NetSendUDPPacket()
function expects to use the NetTxPacket as a buffer and will write
header information into it.  The NetSendPacket() function takes the
packet buffer itself as a parameter, so it isn't expecting anything as
a side-band precondition to avoid crashing.  I specifically added the
check because the failure to initialize NetTxPacket in all code paths
caused problems.  It is easy to run into this if someone were to add a
new thing that can send a packet.  I will change it to an assert.

-Joe