colo-compare: Fix memory leak in packet_enqueue()

The patch is to fix the "pkt" memory leak in packet_enqueue().
The allocated "pkt" needs to be freed if the colo compare
primary or secondary queue is too big.

Replace the error_report of full queue with a trace event.

Signed-off-by: Derek Su <[email protected]>
Reviewed-by: Zhang Chen <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Signed-off-by: Zhang Chen <[email protected]>
Signed-off-by: Jason Wang <[email protected]>

Author: derekbit

net/colo-compare.c

@@ -146,6 +146,10 @@ enum {
     SECONDARY_IN,
 };
 
+static const char *colo_mode[] = {
+    [PRIMARY_IN] = "primary",
+    [SECONDARY_IN] = "secondary",
+};
 
 static int compare_chr_send(CompareState *s,
                             uint8_t *buf,
@@ -242,6 +246,7 @@ static int packet_enqueue(CompareState *s, int mode, Connection **con)
     ConnectionKey key;
     Packet *pkt = NULL;
     Connection *conn;
+    int ret;
 
     if (mode == PRIMARY_IN) {
         pkt = packet_new(s->pri_rs.buf,
@@ -270,16 +275,18 @@ static int packet_enqueue(CompareState *s, int mode, Connection **con)
     }
 
     if (mode == PRIMARY_IN) {
-        if (!colo_insert_packet(&conn->primary_list, pkt, &conn->pack)) {
-            error_report("colo compare primary queue size too big,"
-                         "drop packet");
-        }
+        ret = colo_insert_packet(&conn->primary_list, pkt, &conn->pack);
     } else {
-        if (!colo_insert_packet(&conn->secondary_list, pkt, &conn->sack)) {
-            error_report("colo compare secondary queue size too big,"
-                         "drop packet");
-        }
+        ret = colo_insert_packet(&conn->secondary_list, pkt, &conn->sack);
     }
+
+    if (!ret) {
+        trace_colo_compare_drop_packet(colo_mode[mode],
+            "queue size too big, drop packet");
+        packet_destroy(pkt, NULL);
+        pkt = NULL;
+    }
+
     *con = conn;
 
     return 0;

net/trace-events

@@ -12,6 +12,7 @@ colo_proxy_main(const char *chr) ": %s"
 
 # colo-compare.c
 colo_compare_main(const char *chr) ": %s"
+colo_compare_drop_packet(const char *queue, const char *chr) ": %s: %s"
 colo_compare_udp_miscompare(const char *sta, int size) ": %s = %d"
 colo_compare_icmp_miscompare(const char *sta, int size) ": %s = %d"
 colo_compare_ip_info(int psize, const char *sta, const char *stb, int ssize, const char *stc, const char *std) "ppkt size = %d, ip_src = %s, ip_dst = %s, spkt size = %d, ip_src = %s, ip_dst = %s"