svn commit: r266211 - stable/9/sys/netinet

[Pyun YongHyeon]

Author: yongari
Date: Fri May 16 05:06:46 2014
New Revision: 266211
URL: http://svnweb.freebsd.org/changeset/base/266211

Log:
  MFC r265942:
    Fix checksum computation.  Previously it didn't include carry.

Modified:
  stable/9/sys/netinet/ip_input.c
Directory Properties:
  stable/9/sys/   (props changed)

Modified: stable/9/sys/netinet/ip_input.c
==============================================================================
--- stable/9/sys/netinet/ip_input.c	Fri May 16 05:05:53 2014	(r266210)
+++ stable/9/sys/netinet/ip_input.c	Fri May 16 05:06:46 2014	(r266211)
@@ -1108,8 +1108,9 @@ found:
 	 * (and not in for{} loop), though it implies we are not going to
 	 * reassemble more than 64k fragments.
 	 */
-	m->m_pkthdr.csum_data =
-	    (m->m_pkthdr.csum_data & 0xffff) + (m->m_pkthdr.csum_data >> 16);
+	while (m->m_pkthdr.csum_data & 0xffff0000)
+		m->m_pkthdr.csum_data = (m->m_pkthdr.csum_data & 0xffff) +
+		    (m->m_pkthdr.csum_data >> 16);
 #ifdef MAC
 	mac_ipq_reassemble(fp, m);
 	mac_ipq_destroy(fp);