diff --git a/CHANGES b/CHANGES
index be5a479ac8..09ff3a5bc1 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,6 @@
+6383.	[bug]		Address an infinite loop in $GENERATE when a negative
+			value was converted in nibble mode. [GL #4353]
+
 6382.	[bug]		Fix RPZ response's SOA record TTL, which was incorrectly
 			set to 1 if 'add-soa' is used. [GL #3323]
 
diff --git a/bin/tests/system/checkzone/zones/good-generate-modifier.db b/bin/tests/system/checkzone/zones/good-generate-modifier.db
index 3c811d60e0..be4be18dc2 100644
--- a/bin/tests/system/checkzone/zones/good-generate-modifier.db
+++ b/bin/tests/system/checkzone/zones/good-generate-modifier.db
@@ -18,3 +18,4 @@ $GENERATE 0-7   host$	A 1.2.3.${1,0,d}
 $GENERATE 8-9   host$	A 1.2.3.${1,0}
 $GENERATE 10-11 host$	A 1.2.3.${1}
 $GENERATE 1024-1026 ${0,3,n}	AAAA 2001:db8::${0,4,x}
+$GENERATE 1024-1026 ${-2000,0,n}	AAAA 2001:db8::${0,4,x}
diff --git a/lib/dns/master.c b/lib/dns/master.c
index c785022721..eab1d00364 100644
--- a/lib/dns/master.c
+++ b/lib/dns/master.c
@@ -626,7 +626,8 @@ static const char *hex = "0123456789abcdef0123456789ABCDEF";
  * counting the terminating NUL.
  */
 static unsigned int
-nibbles(char *numbuf, size_t length, unsigned int width, char mode, int value) {
+nibbles(char *numbuf, size_t length, unsigned int width, char mode,
+	unsigned int value) {
 	unsigned int count = 0;
 
 	/*