From fb18e82331b62c2a338d5b8f13ec446b04fad78d Mon Sep 17 00:00:00 2001
From: drh <drh@noemail.net>
Date: Tue, 3 Sep 2019 18:43:33 +0000
Subject: [PATCH] Fix a buffer overread that could occur when running fts5
 prefix queries inside a transaction.

FossilOrigin-Name: 0770363b30382af76e87009192f3b59b8b089e2e2ad3dfac3392f52e78633a3b
---
 ext/fts5/fts5_hash.c      |  4 +++-
 ext/fts5/test/fts5aa.test | 13 +++++++++++--
 manifest                  | 16 ++++++++--------
 manifest.uuid             |  2 +-
 4 files changed, 23 insertions(+), 12 deletions(-)

diff --git a/ext/fts5/fts5_hash.c b/ext/fts5/fts5_hash.c
index 1327597ce7..69e67fa468 100644
--- a/ext/fts5/fts5_hash.c
+++ b/ext/fts5/fts5_hash.c
@@ -444,7 +444,9 @@ static int fts5HashEntrySort(
   for(iSlot=0; iSlot<pHash->nSlot; iSlot++){
     Fts5HashEntry *pIter;
     for(pIter=pHash->aSlot[iSlot]; pIter; pIter=pIter->pHashNext){
-      if( pTerm==0 || 0==memcmp(fts5EntryKey(pIter), pTerm, nTerm) ){
+      if( pTerm==0 
+       || (pIter->nKey+1>=nTerm && 0==memcmp(fts5EntryKey(pIter), pTerm, nTerm))
+      ){
         Fts5HashEntry *pEntry = pIter;
         pEntry->pScanNext = 0;
         for(i=0; ap[i]; i++){
diff --git a/ext/fts5/test/fts5aa.test b/ext/fts5/test/fts5aa.test
index 64c5331c64..43942ca598 100644
--- a/ext/fts5/test/fts5aa.test
+++ b/ext/fts5/test/fts5aa.test
@@ -591,9 +591,18 @@ do_execsql_test 22.1 {
   SELECT rowid FROM t9('a*')
 } {1}
 
-}
 
+do_execsql_test 25.0 {
+  CREATE VIRTUAL TABLE t13 USING fts5(x, detail=%DETAIL%);
+}
+do_execsql_test 25.1 {
+  BEGIN;
+  INSERT INTO t13 VALUES('AAAA');
+SELECT * FROM t13('BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB*');
 
-finish_test
+  END;
+}
 
+}
 
+finish_test
diff --git a/manifest b/manifest
index 2a16c720d1..a92f8aa900 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Disable\sthe\sundocumented\srtreenode()\sSQL\sfunction\sthat\sis\sonly\sused\sfor\stesting,\nexcept\swhen\sdoing\sa\sbuild\sthat\sis\sspecifically\sintended\sfor\stesting.
-D 2019-09-03T17:55:55.993
+C Fix\sa\sbuffer\soverread\sthat\scould\soccur\swhen\srunning\sfts5\sprefix\squeries\sinside\sa\stransaction.
+D 2019-09-03T18:43:33.704
 F Makefile.in 1cc758ce3374a32425e4d130c2fe7b026b20de5b8843243de75f087c0a2661fb
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 8eeb80162074004e906b53d7340a12a14c471a83743aab975947e95ce061efcc
@@ -104,7 +104,7 @@ F ext/fts5/fts5_aux.c 67acf8d51723cf28ffc3828210ba662df4b8d267
 F ext/fts5/fts5_buffer.c 1dd1ec0446b3acfc2d7d407eb894762a461613e2695273f48e449bfd13e973ff
 F ext/fts5/fts5_config.c 5af9c360e99669d29f06492c370892394aba0857
 F ext/fts5/fts5_expr.c f2825f714d91bbe62ab5820aee9ad12e0c94205b2a01725eaa9072415ae9ff1c
-F ext/fts5/fts5_hash.c 534d5591f479c0999543689122ad6952823bc7c85273a0ff4f7f91d9f914a54b
+F ext/fts5/fts5_hash.c d1e75e7645b3d661a2d5645c3c3d618249611d721354097d8e6b5c66ca754e2b
 F ext/fts5/fts5_index.c cdceac47287c66500214ee946ca871ac48027a82a0ca82177c1c6af19f181ca0
 F ext/fts5/fts5_main.c 1ba0e7806886c1bc16e20d0dde1c2b535d1aeb98cbbb937c4c3e064af5ac6f03
 F ext/fts5/fts5_storage.c 7750986004f3f0c94619a85ecb5dd6cbef53e5e3853488e8a906c269d4d11db6
@@ -118,7 +118,7 @@ F ext/fts5/fts5_vocab.c e44fefa7f0c1db252998af071daf06a7147e17e7
 F ext/fts5/fts5parse.y a070b538e08ae9e2177d15c337ed2a3464408f0f886e746307098f746efd94ca
 F ext/fts5/mkportersteps.tcl 5acf962d2e0074f701620bb5308155fa1e4a63ba
 F ext/fts5/test/fts5_common.tcl b01c584144b5064f30e6c648145a2dd6bc440841
-F ext/fts5/test/fts5aa.test 6dd1bfa4426a8d77e8c8d447aad02515c85118b082f24053ac89802300077ff1
+F ext/fts5/test/fts5aa.test e23fcbde0fc453a3c268aac90ea28f8a80489ed49c733ba8dd6b5148ae1a5893
 F ext/fts5/test/fts5ab.test 30325a89453280160106be411bba3acf138e6d1b
 F ext/fts5/test/fts5ac.test 55cad4275a1f5acabfe14d8442a8046b47e49e5f
 F ext/fts5/test/fts5ad.test 36995f0586f30f5602074e012b9224c71ec5171c
@@ -1583,8 +1583,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 553a923c82e968104296253d07dc6e1219747d85ebb7b02640d33d7056418df4
-Q +7b4583f932ff0933280aa73ee69294b488f96d4f2bdc8422cd0136d944d9fb60
-R 160479229dfaf50c9c28f49f4cd87a8e
+P 34cd2d929e21e41373368da846ae4ddd6385c7ba0c45410903717a07aab862a3
+Q +b3fa58dd7403dbd4d2e9f3ae23d7d1337830d6fef2aa2f137ac5174de0d5828e
+R f471046159000a987d436b75b5cec47d
 U drh
-Z ac3d589fe78ec5d9641a884a62646a8f
+Z 9e3f267447b1acdc339d2688519c1ae7
diff --git a/manifest.uuid b/manifest.uuid
index 06e3a0c425..80bbe50666 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-34cd2d929e21e41373368da846ae4ddd6385c7ba0c45410903717a07aab862a3
\ No newline at end of file
+0770363b30382af76e87009192f3b59b8b089e2e2ad3dfac3392f52e78633a3b
\ No newline at end of file
-- 
2.39.5