From: drh <drh@noemail.net>
Date: Tue, 1 Jun 2010 12:58:41 +0000 (+0000)
Subject: Fix an off-by-one boundary-value issue in walCleanupHash().
X-Git-Tag: version-3.7.2~328^2~3
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9c1564779e367e501e425342eee6eb57a1804d4c;p=thirdparty%2Fsqlite.git

Fix an off-by-one boundary-value issue in walCleanupHash().

FossilOrigin-Name: f039552e6330b6a04281748f985b41937f534bd0
---

diff --git a/manifest b/manifest
index e7ae6774aa..c429dfe94f 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,8 @@
-C Do\snot\shold\sthe\sshared-memory\smutex\sin\sos_unix.c\sif\sreturning\sNULL.
-D 2010-06-01T11:08:57
+-----BEGIN PGP SIGNED MESSAGE-----
+Hash: SHA1
+
+C Fix\san\soff-by-one\sboundary-value\sissue\sin\swalCleanupHash().
+D 2010-06-01T12:58:41
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in a5cad1f8f3e021356bfcc6c77dc16f6f1952bbc3
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -224,7 +227,7 @@ F src/vdbeblob.c 5327132a42a91e8b7acfb60b9d2c3b1c5c863e0e
 F src/vdbemem.c 2a82f455f6ca6f78b59fb312f96054c04ae0ead1
 F src/vdbetrace.c 864cef96919323482ebd9986f2132435115e9cc2
 F src/vtab.c a0f8a40274e4261696ef57aa806de2776ab72cda
-F src/wal.c a18a20596b8b9ea09ed9c8741f9193e165f0cb6f
+F src/wal.c 2a122212dcf4c3955f0c481423d1229f2de243c5
 F src/wal.h 1c1c9feb629b7f4afcbe0b47f80f47c5551d3a02
 F src/walker.c 3112bb3afe1d85dc52317cb1d752055e9a781f8f
 F src/where.c 75fee9e255b62f773fcadd1d1f25b6f63ac7a356
@@ -815,7 +818,14 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P 9e95e35728cf69a0ae50e774d7f6c71a41b17d97
-R 67ccfc3b179b63c3e3b80e2b7e1142bd
-U dan
-Z 560dece5b4a16dc5e0eff482c3f02a96
+P 9622dd468c8914262e9d8bd8dbca9e22ec6ee75c
+R 2027cf2e3628664b2b4aeae9063b73e6
+U drh
+Z 6523cefeaece12ca468a422414c222b4
+-----BEGIN PGP SIGNATURE-----
+Version: GnuPG v1.4.6 (GNU/Linux)
+
+iD8DBQFMBQQFoxKgR168RlERArWrAJkB9UGjRw3tmehhDr5P1HYBMojm4gCfca8+
+OpbJgYgS2VEE4rPB1ieyWGg=
+=X2Kt
+-----END PGP SIGNATURE-----
diff --git a/manifest.uuid b/manifest.uuid
index 82274c2ee1..0d9463041f 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-9622dd468c8914262e9d8bd8dbca9e22ec6ee75c
\ No newline at end of file
+f039552e6330b6a04281748f985b41937f534bd0
\ No newline at end of file
diff --git a/src/wal.c b/src/wal.c
index 49becd0e0a..48b9c04b5f 100644
--- a/src/wal.c
+++ b/src/wal.c
@@ -822,11 +822,16 @@ static void walCleanupHash(Wal *pWal){
   int iLimit;                          /* Zero values greater than this */
 
   assert( pWal->writeLock );
-  walHashFind(pWal, pWal->hdr.mxFrame+1, &aHash, &aPgno, &iZero);
-  iLimit = pWal->hdr.mxFrame - iZero;
-  if( iLimit>0 ){
+  testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE-1 );
+  testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE );
+  testcase( pWal->hdr.mxFrame==HASHTABLE_NPAGE+1 );
+  if( (pWal->hdr.mxFrame % HASHTABLE_NPAGE)>0 ){
     int nByte;                    /* Number of bytes to zero in aPgno[] */
     int i;                        /* Used to iterate through aHash[] */
+
+    walHashFind(pWal, pWal->hdr.mxFrame+1, &aHash, &aPgno, &iZero);
+    iLimit = pWal->hdr.mxFrame - iZero;
+    assert( iLimit>0 );
     for(i=0; i<HASHTABLE_NSLOT; i++){
       if( aHash[i]>iLimit ){
         aHash[i] = 0;