[dhcp/f14/master] Do not bring the interface down (#574568)

[Jiří Popelka]

commit 3127c5a1a61b07b9defe0be3d9d3e864c4ea10b5
Author: Jiri Popelka <jpopelka at redhat.com>
Date:   Thu Sep 30 15:49:08 2010 +0200

    Do not bring the interface down (#574568)

 dhclient-script |   21 +++++++++++++--------
 dhcp.spec       |   12 ++++++++----
 2 files changed, 21 insertions(+), 12 deletions(-)
---
diff --git a/dhclient-script b/dhclient-script
index 9290d91..1cd4ee0 100755
--- a/dhclient-script
+++ b/dhclient-script
@@ -256,6 +256,14 @@ add_default_gateway() {
     return 1
 }
 
+flush_dev() {
+# Instead of bringing the interface down (#574568)
+# explicitly clear the ARP cache and flush all addresses & routes.
+    ip -4 addr flush dev ${1} >/dev/null 2>&1
+    ip -4 route flush dev ${1} >/dev/null 2>&1
+    ip -4 neigh flush dev ${1} >/dev/null 2>&1
+}
+
 dhconfig() {
     if [ -n "${old_ip_address}" ] && [ -n "${alias_ip_address}" ] &&
        [ ! "${alias_ip_address}" = "${old_ip_address}" ]; then
@@ -265,9 +273,8 @@ dhconfig() {
 
     if [ -n "${old_ip_address}" ] &&
        [ ! "${old_ip_address}" = "${new_ip_address}" ]; then
-        # IP address changed.  Bringing down the interface will delete all
-        # routes, and clear the ARP cache.
-        ip -4 addr flush dev ${interface} >/dev/null 2>&1
+        # IP address changed. Delete all routes, and clear the ARP cache.
+        flush_dev ${interface}
     fi
 
     if [ "${reason}" = "BOUND" ] || [ "${reason}" = "REBOOT" ] ||
@@ -710,9 +717,8 @@ case "${reason}" in
         fi
 
         if [ -n "${old_ip_address}" ]; then
-            # Shut down interface, which will delete routes and clear arp cache.
-            ip -4 addr flush dev ${interface} >/dev/null 2>&1
-            ip link set ${interface} down
+            # Delete addresses/routes/arp cache.
+            flush_dev ${interface}
         fi
 
         if [ -n "${alias_ip_address}" ]; then
@@ -737,8 +743,7 @@ case "${reason}" in
                 exit_with_hooks 0
             fi
 
-            ip -4 addr flush dev ${interface} >/dev/null 2>&1
-            ip link set ${interface} down
+            flush_dev ${interface}
             exit_with_hooks 1
         else
             exit_with_hooks 1
diff --git a/dhcp.spec b/dhcp.spec
index c3b4e7c..4a9d798 100644
--- a/dhcp.spec
+++ b/dhcp.spec
@@ -7,7 +7,7 @@
 Summary:  Dynamic host configuration protocol software
 Name:     dhcp
 Version:  4.2.0
-Release:  7%{?dist}
+Release:  8%{?dist}
 # NEVER CHANGE THE EPOCH on this package.  The previous maintainer (prior to
 # dcantrell maintaining the package) made incorrect use of the epoch and
 # that's why it is at 12 now.  It should have never been used, but it was.
@@ -515,13 +515,17 @@ fi
 %attr(0644,root,root) %{_mandir}/man3/omapi.3.gz
 
 %changelog
-* Tue Sep 7 2010 Jiri Popelka <jpopelka at redhat.com> - 12:4.2.0-7
+* Thu Sep 30 2010 Jiri Popelka <jpopelka at redhat.com> - 12:4.2.0-8
+- Explicitly clear the ARP cache and flush all addresses & routes
+  instead of bringing the interface down (#574568)
+
+* Tue Sep 07 2010 Jiri Popelka <jpopelka at redhat.com> - 12:4.2.0-7
 - Hardening dhcpd/dhcrelay/dhclient by making them PIE & RELRO
 
-* Thu Sep 2 2010 Jiri Popelka <jpopelka at redhat.com> - 12:4.2.0-6
+* Thu Sep 02 2010 Jiri Popelka <jpopelka at redhat.com> - 12:4.2.0-6
 - Another fix for handling time values on 64-bit platforms (#628258)
 
-* Wed Sep 1 2010 Jiri Popelka <jpopelka at redhat.com> - 12:4.2.0-5
+* Wed Sep 01 2010 Jiri Popelka <jpopelka at redhat.com> - 12:4.2.0-5
 - Fix parsing of lease file dates & times on 64-bit platforms (#628258)
 
 * Tue Aug 31 2010 Jiri Popelka <jpopelka at redhat.com> - 12:4.2.0-4