svn commit: r331484 - head/sys/netinet6

[Jonathan T. Looney]

Author: jtl
Date: Sat Mar 24 12:43:34 2018
New Revision: 331484
URL: https://svnweb.freebsd.org/changeset/base/331484

Log:
  Remove some unneccessary variable sets in IPv6 code, as detected by
  clang's static analyzer.
  
  Reviewed by:	bz
  MFC after:	2 weeks
  Sponsored by:	Netflix, Inc.
  Differential Revision:	https://reviews.freebsd.org/D10940

Modified:
  head/sys/netinet6/dest6.c
  head/sys/netinet6/icmp6.c
  head/sys/netinet6/ip6_output.c
  head/sys/netinet6/udp6_usrreq.c

Modified: head/sys/netinet6/dest6.c
==============================================================================
--- head/sys/netinet6/dest6.c	Sat Mar 24 12:40:45 2018	(r331483)
+++ head/sys/netinet6/dest6.c	Sat Mar 24 12:43:34 2018	(r331484)
@@ -93,7 +93,7 @@ dest6_input(struct mbuf **mp, int *offp, int proto)
 	opt = (u_int8_t *)dstopts + sizeof(struct ip6_dest);
 
 	/* search header for all options. */
-	for (optlen = 0; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) {
+	for (; dstoptlen > 0; dstoptlen -= optlen, opt += optlen) {
 		if (*opt != IP6OPT_PAD1 &&
 		    (dstoptlen < IP6OPT_MINLEN || *(opt + 1) + 2 > dstoptlen)) {
 			IP6STAT_INC(ip6s_toosmall);

Modified: head/sys/netinet6/icmp6.c
==============================================================================
--- head/sys/netinet6/icmp6.c	Sat Mar 24 12:40:45 2018	(r331483)
+++ head/sys/netinet6/icmp6.c	Sat Mar 24 12:43:34 2018	(r331484)
@@ -594,7 +594,6 @@ icmp6_input(struct mbuf **mp, int *offp, int proto)
 			n->m_pkthdr.len = n0len + (noff - off);
 			n->m_next = n0;
 		} else {
-			nip6 = mtod(n, struct ip6_hdr *);
 			IP6_EXTHDR_GET(nicmp6, struct icmp6_hdr *, n, off,
 			    sizeof(*nicmp6));
 			noff = off;

Modified: head/sys/netinet6/ip6_output.c
==============================================================================
--- head/sys/netinet6/ip6_output.c	Sat Mar 24 12:40:45 2018	(r331483)
+++ head/sys/netinet6/ip6_output.c	Sat Mar 24 12:43:34 2018	(r331484)
@@ -1048,7 +1048,7 @@ sendorfree:
 	m = m0->m_nextpkt;
 	m0->m_nextpkt = 0;
 	m_freem(m0);
-	for (m0 = m; m; m = m0) {
+	for (; m; m = m0) {
 		m0 = m->m_nextpkt;
 		m->m_nextpkt = 0;
 		if (error == 0) {

Modified: head/sys/netinet6/udp6_usrreq.c
==============================================================================
--- head/sys/netinet6/udp6_usrreq.c	Sat Mar 24 12:40:45 2018	(r331483)
+++ head/sys/netinet6/udp6_usrreq.c	Sat Mar 24 12:43:34 2018	(r331484)
@@ -220,7 +220,6 @@ udp6_input(struct mbuf **mp, int *offp, int proto)
 	uint8_t nxt;
 
 	ifp = m->m_pkthdr.rcvif;
-	ip6 = mtod(m, struct ip6_hdr *);
 
 #ifndef PULLDOWN_TEST
 	IP6_EXTHDR_CHECK(m, off, sizeof(struct udphdr), IPPROTO_DONE);
@@ -230,6 +229,7 @@ udp6_input(struct mbuf **mp, int *offp, int proto)
 	IP6_EXTHDR_GET(uh, struct udphdr *, m, off, sizeof(*uh));
 	if (!uh)
 		return (IPPROTO_DONE);
+	ip6 = mtod(m, struct ip6_hdr *);
 #endif
 
 	UDPSTAT_INC(udps_ipackets);