COLO-compare: Fix incorrect `if` logic

'colo_mark_tcp_pkt' should return 'true' when packets are the same, and
'false' otherwise.  However, it returns 'true' when
'colo_compare_packet_payload' returns non-zero while
'colo_compare_packet_payload' is just a 'memcmp'.  The result is that
COLO-compare reports inconsistent TCP packets when they are actually
the same.

Fixes: f449c9e5 ("colo: compare the packet based on the tcp sequence number")
Cc: qemu-stable@nongnu.org
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: NFan Yang <Fan_Yang@sjtu.edu.cn>
Signed-off-by: NJason Wang <jasowang@redhat.com>
(cherry picked from commit 1e907a32)
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

net/colo-compare.c

@@ -319,7 +319,7 @@ static bool colo_mark_tcp_pkt(Packet *ppkt, Packet *spkt,
     *mark = 0;
 
     if (ppkt->tcp_seq == spkt->tcp_seq && ppkt->seq_end == spkt->seq_end) {
-        if (colo_compare_packet_payload(ppkt, spkt,
+        if (!colo_compare_packet_payload(ppkt, spkt,
                                         ppkt->header_size, spkt->header_size,
                                         ppkt->payload_size)) {
             *mark = COLO_COMPARE_FREE_SECONDARY | COLO_COMPARE_FREE_PRIMARY;
@@ -329,7 +329,7 @@ static bool colo_mark_tcp_pkt(Packet *ppkt, Packet *spkt,
 
     /* one part of secondary packet payload still need to be compared */
     if (!after(ppkt->seq_end, spkt->seq_end)) {
-        if (colo_compare_packet_payload(ppkt, spkt,
+        if (!colo_compare_packet_payload(ppkt, spkt,
                                         ppkt->header_size + ppkt->offset,
                                         spkt->header_size + spkt->offset,
                                         ppkt->payload_size - ppkt->offset)) {
@@ -348,7 +348,7 @@ static bool colo_mark_tcp_pkt(Packet *ppkt, Packet *spkt,
         /* primary packet is longer than secondary packet, compare
          * the same part and mark the primary packet offset
          */
-        if (colo_compare_packet_payload(ppkt, spkt,
+        if (!colo_compare_packet_payload(ppkt, spkt,
                                         ppkt->header_size + ppkt->offset,
                                         spkt->header_size + spkt->offset,
                                         spkt->payload_size - spkt->offset)) {