[TS-913]<fix>: fixed coredump when memcpy without checking the length

src/plugins/http/src/httpGcJson.c

@@ -129,7 +129,7 @@ bool gcBuildQueryJson(HttpContext *pContext, HttpSqlCmd *cmd, TAOS_RES *result,
 
     // for group by
     if (groupFields != -1) {
-      char    target[HTTP_GC_TARGET_SIZE] = {0};
+      char    target[HTTP_GC_TARGET_SIZE << 5] = {0};
       int32_t len;
       len = snprintf(target, HTTP_GC_TARGET_SIZE, "%s{", aliasBuffer);
       for (int32_t i = dataFields + 1; i < num_fields; i++) {
@@ -167,7 +167,7 @@ bool gcBuildQueryJson(HttpContext *pContext, HttpSqlCmd *cmd, TAOS_RES *result,
           case TSDB_DATA_TYPE_NCHAR:
             if (row[i] != NULL) {
               len += snprintf(target + len, HTTP_GC_TARGET_SIZE - len, "%s:", fields[i].name);
-              memcpy(target + len, (char *)row[i], length[i]);
+              memcpy(target + len, (char *)row[i], MIN(length[i], HTTP_GC_TARGET_SIZE - 1 - len));
               len = (int32_t)strlen(target);
             }
             break;

tests/script/general/http/grafana.sim

@@ -50,6 +50,9 @@ sql insert into t3 values('2017-12-25 21:25:41', 3)
 sql insert into t3 values('2017-12-25 21:26:41', 3)
 sql insert into t3 values('2017-12-25 21:27:41', 3)
 
+sql create table m3 (ts timestamp, col1 int, col2 float, txt binary(500))
+sql insert into m3 values(now, 1, 2.0, 'HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS')
+
 print ===============  step2 - login
 
 system_content curl 127.0.0.1:7111/grafana/
@@ -179,4 +182,10 @@ if $system_content != @[{"refId":"A","target":"{count(v1):3}","datapoints":[[15.
   return -1
 endi
 
+system_content curl -H 'Authorization: Taosd /KfeAzX/f9na8qdtNZmtONryp201ma04bEl8LcvLUd7a8qdtNZmtONryp201ma04' -d '[{"refId":"A","alias":"taosd","sql":"select last(col1), last(col2), last(txt) from d1.m3 group by txt"}]' 127.0.0.1:7111/grafana/query
+print 20-> $system_content
+if $system_content != @[{"refId":"A","target":"taosd{last(col2):2.00000, last(txt):HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HELLO TAOS HE","datapoints":[[1,"-"]]}]@ then
+  return -1
+endi
+
 system sh/exec.sh -n dnode1 -s stop -x SIGINT