Fix a page-cache reference leak in the btree balancer when there is a corrupt

database.

FossilOrigin-Name: 9285899120dec24ff2944431ad455d7ae217ef408ae2f1a3e7bdfb897099028c

manifest

@@ -1,5 +1,5 @@
-C Defer\scomputing\sthe\sMemPage.nFree\svalue\sof\san\sin-memory\sbtree\spage\nuntil\sit\sis\sactually\sneeded,\ssince\sfor\smany\spages\sit\sis\snever\sneeded.\nThis\scheckin\sworks\ssufficiently\sto\sprove\sthe\sconcept,\sbut\sstill\shas\sissues\nwith\sexception\shandling.
-D 2019-02-09T21:06:40.308
+C Fix\sa\spage-cache\sreference\sleak\sin\sthe\sbtree\sbalancer\swhen\sthere\sis\sa\scorrupt\ndatabase.
+D 2019-02-09T22:33:44.636
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F Makefile.in 178d8eb6840771149cee40b322d1b3be30d330198c522c903c1b66fb5a1bfca4
@@ -455,7 +455,7 @@ F src/auth.c 0fac71038875693a937e506bceb492c5f136dd7b1249fbd4ae70b4e8da14f9df
 F src/backup.c 78d3cecfbe28230a3a9a1793e2ead609f469be43e8f486ca996006be551857ab
 F src/bitvec.c 17ea48eff8ba979f1f5b04cc484c7bb2be632f33
 F src/btmutex.c 8acc2f464ee76324bf13310df5692a262b801808984c1b79defb2503bbafadb6
-F src/btree.c b2bb677fa5d2f18b7c38869761e0d7d1d66ff3a7bdac509865e0606b281d32bc
+F src/btree.c 0c9455de1fea43ac2d1384383ae0034c59a9b2a60f12b7eeb934ba27abc91f2b
 F src/btree.h 63b94fb38ce571c15eb6a3661815561b501d23d5948b2d1e951fbd7a2d04e8d3
 F src/btreeInt.h d7520b98e72f9a7e2a3140cc476df461fa8a34a3d56258184f8c26f70248cef9
 F src/build.c 906ca6663b9dcd413e72ae9c44dd51e596d8336b04d52e678a7501e71c20cab2
@@ -1804,10 +1804,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P db74a56af73d92b7a9d43ceda7e4540915c580c68a0266b4ddefb9e0d5cbcbeb
-R 6351a98578ba74f863fbe86b96b0dce9
-T *branch * deferred-free-space
-T *sym-deferred-free-space *
-T -sym-trunk *
+P 1d43ee4000b71f5c6d49244dee96358c567f09ba3451b9d22895a796d3f61ad6
+R b28deed0efae0448ead27e80a7ddacc4
 U drh
-Z 38c6e8e54a38cca2a22ac1c0553f905f
+Z 26932f3ade712321f925e8e95108ce1e

manifest.uuid

@@ -1 +1 @@
-1d43ee4000b71f5c6d49244dee96358c567f09ba3451b9d22895a796d3f61ad6
+9285899120dec24ff2944431ad455d7ae217ef408ae2f1a3e7bdfb897099028c

src/btree.c

@@ -7550,13 +7550,17 @@ static int balance_nonroot(
   pgno = get4byte(pRight);
   while( 1 ){
     rc = getAndInitPage(pBt, pgno, &apOld[i], 0, 0);
-    if( rc==0 && apOld[i]->nFree<0 ){
-      rc = btreeComputeFreeSpace(apOld[i]);
-    }
     if( rc ){
       memset(apOld, 0, (i+1)*sizeof(MemPage*));
       goto balance_cleanup;
     }
+    if( apOld[i]->nFree<0 ){
+      rc = btreeComputeFreeSpace(apOld[i]);
+      if( rc ){
+        memset(apOld, 0, (i)*sizeof(MemPage*));
+        goto balance_cleanup;
+      }
+    }
     nMaxCells += 1+apOld[i]->nCell+apOld[i]->nOverflow;
     if( (i--)==0 ) break;