fix: coverity scan problem

source/dnode/vnode/src/meta/metaTable.c

@@ -668,6 +668,11 @@ static int metaAlterTableColumn(SMeta *pMeta, int64_t version, SVAlterTbReq *pAl
   SSchemaWrapper *pSchema;
   int             c;
 
+  if (pAlterTbReq->colName == NULL) {
+    terrno = TSDB_CODE_INVALID_MSG;
+    return -1;
+  }
+
   // search name index
   ret = tdbTbGet(pMeta->pNameIdx, pAlterTbReq->tbName, strlen(pAlterTbReq->tbName) + 1, &pVal, &nVal);
   if (ret < 0) {

source/dnode/vnode/src/tsdb/tsdbCommit.c

@@ -1054,6 +1054,7 @@ static int32_t tsdbEndCommit(SCommitter *pCommitter, int32_t eno) {
 _exit:
   tsdbFSDestroy(&pCommitter->fs);
   taosArrayDestroy(pCommitter->aTbDataP);
+  pCommitter->aTbDataP = NULL;
   if (code || eno) {
     tsdbError("vgId:%d %s failed at line %d since %s", TD_VID(pTsdb->pVnode), __func__, lino, tstrerror(code));
   } else {

source/dnode/vnode/src/tsdb/tsdbFS.c

@@ -149,6 +149,7 @@ _exit:
 void tsdbFSDestroy(STsdbFS *pFS) {
   if (pFS->pDelFile) {
     taosMemoryFree(pFS->pDelFile);
+    pFS->pDelFile = NULL;
   }
 
   for (int32_t iSet = 0; iSet < taosArrayGetSize(pFS->aDFileSet); iSet++) {
@@ -162,6 +163,7 @@ void tsdbFSDestroy(STsdbFS *pFS) {
   }
 
   taosArrayDestroy(pFS->aDFileSet);
+  pFS->aDFileSet = NULL;
 }
 
 static int32_t tsdbScanAndTryFixFS(STsdb *pTsdb) {
@@ -296,7 +298,7 @@ static int32_t tsdbLoadFSFromFile(const char *fname, STsdbFS *pFS) {
   // load binary
   TdFilePtr pFD = taosOpenFile(fname, TD_FILE_READ);
   if (pFD == NULL) {
-    code = terrno;
+    code = TAOS_SYSTEM_ERROR(errno);
     TSDB_CHECK_CODE(code, lino, _exit);
   }
 

source/dnode/vnode/src/tsdb/tsdbRetention.c

@@ -47,7 +47,7 @@ int32_t tsdbDoRetention(STsdb *pTsdb, int64_t now) {
   }
 
   // do retention
-  STsdbFS fs;
+  STsdbFS fs = {0};
 
   code = tsdbFSCopy(pTsdb, &fs);
   if (code) goto _err;