Fix a couple of memory-sanitizer complaints that could be triggered by a corrupt database.

Author: danielk-1977

src/btree.c

@@ -7637,7 +7637,9 @@ static int balance_nonroot(
   }
   pgno = get4byte(pRight);
   while( 1 ){
-    rc = getAndInitPage(pBt, pgno, &apOld[i], 0, 0);
+    if( rc==SQLITE_OK ){
+      rc = getAndInitPage(pBt, pgno, &apOld[i], 0, 0);
+    }
     if( rc ){
       memset(apOld, 0, (i+1)*sizeof(MemPage*));
       goto balance_cleanup;
@@ -7676,12 +7678,10 @@ static int balance_nonroot(
       if( pBt->btsFlags & BTS_FAST_SECURE ){
         int iOff;
 
+        /* If the following if() condition is not true, the db is corrupted.
+        ** The call to dropCell() below will detect this.  */
         iOff = SQLITE_PTR_TO_INT(apDiv[i]) - SQLITE_PTR_TO_INT(pParent->aData);
-        if( (iOff+szNew[i])>(int)pBt->usableSize ){
-          rc = SQLITE_CORRUPT_BKPT;
-          memset(apOld, 0, (i+1)*sizeof(MemPage*));
-          goto balance_cleanup;
-        }else{
+        if( (iOff+szNew[i])<=(int)pBt->usableSize ){
           memcpy(&aOvflSpace[iOff], apDiv[i], szNew[i]);
           apDiv[i] = &aOvflSpace[apDiv[i]-pParent->aData];
         }

src/pcache1.c

@@ -461,6 +461,7 @@ static PgHdr1 *pcache1AllocPage(PCache1 *pCache, int benignMalloc){
     p->page.pExtra = &p[1];
     p->isBulkLocal = 0;
     p->isAnchor = 0;
+    p->pLruPrev = 0;           /* Initializing this saves a valgrind error */
   }
   (*pCache->pnPurgeable)++;
   return p;