diff -Nru collectd-5.4.0/debian/changelog collectd-5.4.0/debian/changelog
--- collectd-5.4.0/debian/changelog	2016-04-06 15:38:13.000000000 +0200
+++ collectd-5.4.0/debian/changelog	2016-04-06 15:38:14.000000000 +0200
@@ -1,3 +1,12 @@
+collectd (5.4.0-3ubuntu2.2) trusty; urgency=medium
+
+  * debian/patches:
+    - Added bts770688_snmp_memleak: backport of upstream fix for a memory leak in 
+      the SNMP plugin, which is included in 5.4.1-6 unstable; 
+      thanks to Marc Fournier for reporting this.
+
+ -- Akiko Kanno <warau@binary.to>  Wed, 06 Apr 2016 15:12:55 +0200
+
 collectd (5.4.0-3ubuntu2.1) trusty; urgency=medium
 
   * debian/patches:
diff -Nru collectd-5.4.0/debian/patches/00list collectd-5.4.0/debian/patches/00list
--- collectd-5.4.0/debian/patches/00list	2016-04-06 15:38:13.000000000 +0200
+++ collectd-5.4.0/debian/patches/00list	2016-04-06 15:38:14.000000000 +0200
@@ -6,3 +6,4 @@
 ppc64el.dpatch
 libperl-linkage.dpatch
 swap_in_openvz.dpatch
+bts770688_snmp_memleak.dpatch
diff -Nru collectd-5.4.0/debian/patches/bts770688_snmp_memleak.dpatch collectd-5.4.0/debian/patches/bts770688_snmp_memleak.dpatch
--- collectd-5.4.0/debian/patches/bts770688_snmp_memleak.dpatch	1970-01-01 01:00:00.000000000 +0100
+++ collectd-5.4.0/debian/patches/bts770688_snmp_memleak.dpatch	2016-04-06 15:38:14.000000000 +0200
@@ -0,0 +1,53 @@
+#! /bin/sh /usr/share/dpatch/dpatch-run
+## bts770688_snmp_memleak.dpatch by Pierre-Yves Ritschard <pyr@spootnik.org>
+## and Marc Fournier <marc.fournier@camptocamp.com>
+##
+## DP: Let snmp_synch_response deal with PDU freeing
+## DP:
+## DP: When reading from tables, upon errors the PDUs sent are already
+## DP: freed by snmp_synch_response since they are right after
+## DP: snmp_send is called.
+## DP:
+## DP: This commit syncs collectd's approach with other occurences of
+## DP: snmp_synch_response calls.
+## DP:
+## DP: There might be a few corner cases where we leak PDUs, but it
+## DP: is unclear how to check for those since we would need to
+## DP: have an indication that snmp_send was never called, which
+## DP: as far as I can tell is not possible.
+## DP:
+## DP: The potential for failure in snmp_send is rather low and will
+## DP: be easily spotted though, since when crafting invalid PDUs
+## DP: snmp send will constantly fail and since valid configurations
+## DP: can never leak memory.
+## DP:
+## DP: Upstream bug reports:
+## DP: https://github.com/collectd/collectd/issues/610
+## DP: https://github.com/collectd/collectd/issues/804
+
+@DPATCH@
+
+diff --git a/src/snmp.c b/src/snmp.c
+index ad81c89..7d340d1 100644
+--- a/src/snmp.c
++++ b/src/snmp.c
+@@ -1316,6 +1316,8 @@ static int csnmp_read_table (host_definition_t *host, data_definition_t *data)
+         snmp_free_pdu (res);
+       res = NULL;
+ 
++      /* snmp_synch_response already freed our PDU */
++      req = NULL;
+       sfree (errstr);
+       csnmp_host_close_session (host);
+ 
+@@ -1437,6 +1439,10 @@ static int csnmp_read_table (host_definition_t *host, data_definition_t *data)
+     snmp_free_pdu (res);
+   res = NULL;
+ 
++  if (req != NULL)
++    snmp_free_pdu (req);
++  req = NULL;
++
+   if (status == 0)
+     csnmp_dispatch_table (host, data, instance_list_head, value_list_head);
+