[U-Boot] TFTP - check for len == 0 before storing

[David Andrey <David.Andrey@netmodule.com>]

Hello,

I had a problem with an old TFTP Server which is sending a second "last"
data block with "len == 0" at end. It's clearly not RFC conform, but I
still made a additional check in u-boot/tftp to avoid a wrong "filesize"
value. This wrong filesize value caused some trouble by NAND operations.


Regards
David



Date: Wed, 20 Apr 2011 10:12:10 +0200
Subject: [PATCH] Check for for data block len == 0

---
 net/tftp.c |   10 ++++++++--
 1 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/net/tftp.c b/net/tftp.c
index ed559b7..40d81b5 100644
--- a/net/tftp.c
+++ b/net/tftp.c
@@ -135,8 +135,14 @@ mcast_cleanup(void)
 static __inline__ void
 store_block (unsigned block, uchar * src, unsigned len)
 {
-       ulong offset = block * TftpBlkSize + TftpBlockWrapOffset;
-       ulong newsize = offset + len;
+       ulong offset = 0;
+       ulong newsize = 0;
+
+       if (len == 0)
+               return;
+
+       offset = block * TftpBlkSize + TftpBlockWrapOffset;
+       newsize = offset + len;
 #ifdef CONFIG_SYS_DIRECT_FLASH_TFTP
        int i, rc = 0;