BUG/MINOR: http: Missing calloc return value check while parsing tcp-request/tcp-response

A memory allocation failure happening in tcp_parse_tcp_req or
tcp_parse_tcp_rep when trying to allocate an act_rule structure would
have resulted in a crash. These functions are only called during
configuration parsing.

It was raised in GitHub issue #1233.
It could be backported to all stable branches.
diff --git a/src/tcp_rules.c b/src/tcp_rules.c
index 2e1eac4..edc287b 100644
--- a/src/tcp_rules.c
+++ b/src/tcp_rules.c
@@ -1055,6 +1055,10 @@
 	}
 
 	rule = calloc(1, sizeof(*rule));
+	if (!rule) {
+		memprintf(err, "parsing [%s:%d] : out of memory", file, line);
+		return -1;
+	}
 	LIST_INIT(&rule->list);
 	arg = 1;
 	where = 0;
@@ -1169,6 +1173,10 @@
 	}
 
 	rule = calloc(1, sizeof(*rule));
+	if (!rule) {
+		memprintf(err, "parsing [%s:%d] : out of memory", file, line);
+		return -1;
+	}
 	LIST_INIT(&rule->list);
 	arg = 1;
 	where = 0;