Harden the recovery extension against SQL injections coming from the

sqlite_schema table of the database being recovered.

FossilOrigin-Name: 555401fe048a51ecaed3ef672723b6ef8e1340c7028c11a17731abbc399bc078

ext/recover/sqlite3recover.c

@@ -532,18 +532,39 @@ static void recoverFinalize(sqlite3_recover *p, sqlite3_stmt *pStmt){
   }
 }
 
+/*
+** Run a single SQL statement in zSql.  If zSql contains two or more
+** SQL statements separated by ';', only the first is run.
+**
+** Return the sqlite3_finalizer() or sqlite3_prepare() result code
+** from running the zSql statement.
+*/
+static int recoverOneStmt(sqlite3 *db, const char *zSql){
+  sqlite3_stmt *pStmt = 0;
+  int rc;
+  if( zSql==0 ) return SQLITE_OK;
+  rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
+  if( rc ){
+    sqlite3_finalize(pStmt);
+    return rc;
+  }
+  while( SQLITE_ROW==sqlite3_step(pStmt) ){}
+  return sqlite3_finalize(pStmt);
+}
+
 /*
 ** This function is a no-op if recover handle p already contains an error
 ** (if p->errCode!=SQLITE_OK). A copy of p->errCode is returned in this 
 ** case.
 **
-** Otherwise, execute SQL script zSql. If successful, return SQLITE_OK.
-** Or, if an error occurs, leave an error code and message in the recover
-** handle and return a copy of the error code.
+** Otherwise, execute a single SQL statment in zSql.  Even if zSql contains
+** two or more SQL statements separated by ';', only execute the first one.
+** If successful, return SQLITE_OK.  Or, if an error occurs, leave an error
+** code and message in the recover handle and return a copy of the error code.
 */
 static int recoverExec(sqlite3_recover *p, sqlite3 *db, const char *zSql){
   if( p->errCode==SQLITE_OK ){
-    int rc = sqlite3_exec(db, zSql, 0, 0, 0);
+    int rc = recoverOneStmt(db, zSql);
     if( rc ){
       recoverDbError(p, db);
     }
@@ -943,7 +964,8 @@ static void recoverTransferSettings(sqlite3_recover *p){
       }
       recoverFinalize(p, p1);
     }
-    recoverExec(p, db2, "CREATE TABLE t1(a); DROP TABLE t1;");
+    recoverExec(p, db2, "CREATE TABLE t1(a)");
+    recoverExec(p, db2, "DROP TABLE t1");
 
     if( p->errCode==SQLITE_OK ){
       sqlite3 *db = p->dbOut;
@@ -1025,12 +1047,12 @@ static int recoverOpenOutput(sqlite3_recover *p){
 static void recoverOpenRecovery(sqlite3_recover *p){
   char *zSql = recoverMPrintf(p, "ATTACH %Q AS recovery;", p->zStateDb);
   recoverExec(p, p->dbOut, zSql);
-  recoverExec(p, p->dbOut,
-      "PRAGMA writable_schema = 1;"
-      "CREATE TABLE recovery.map(pgno INTEGER PRIMARY KEY, parent INT);" 
-      "CREATE TABLE recovery.schema(type, name, tbl_name, rootpage, sql);"
-  );
   sqlite3_free(zSql);
+  recoverExec(p, p->dbOut, "PRAGMA writable_schema = 1");
+  recoverExec(p, p->dbOut,
+      "CREATE TABLE recovery.map(pgno INTEGER PRIMARY KEY, parent INT)");
+  recoverExec(p, p->dbOut,
+      "CREATE TABLE recovery.schema(type, name, tbl_name, rootpage, sql)");
 }
 
 
@@ -1170,7 +1192,7 @@ static int recoverWriteSchema1(sqlite3_recover *p){
       ")"
       "SELECT rootpage, tbl, isVirtual, name, sql"
       " FROM dbschema "
-      "  WHERE tbl OR isIndex"
+      "  WHERE (tbl OR isIndex) AND sql GLOB 'CREATE *'"
       "  ORDER BY tbl DESC, name=='sqlite_sequence' DESC"
   );
 
@@ -1196,7 +1218,7 @@ static int recoverWriteSchema1(sqlite3_recover *p){
             zName, zName, zSql
         ));
       }
-      rc = sqlite3_exec(p->dbOut, zSql, 0, 0, 0);
+      rc = recoverOneStmt(p->dbOut, zSql);
       if( rc==SQLITE_OK ){
         recoverSqlCallback(p, zSql);
         if( bTable && !bVirtual ){
@@ -1238,15 +1260,17 @@ static int recoverWriteSchema2(sqlite3_recover *p){
       p->bSlowIndexes ?
       "SELECT rootpage, sql FROM recovery.schema "
       "  WHERE type!='table' AND type!='index'"
+      "    AND sql GLOB 'CREATE *'"
       :
       "SELECT rootpage, sql FROM recovery.schema "
       "  WHERE type!='table' AND (type!='index' OR sql NOT LIKE '%unique%')"
+      "    AND sql GLOB 'CREATE *'"
   );
 
   if( pSelect ){
     while( sqlite3_step(pSelect)==SQLITE_ROW ){
       const char *zSql = (const char*)sqlite3_column_text(pSelect, 1);
-      int rc = sqlite3_exec(p->dbOut, zSql, 0, 0, 0);
+      int rc = recoverOneStmt(p->dbOut, zSql);
       if( rc==SQLITE_OK ){
         recoverSqlCallback(p, zSql);
       }else if( rc!=SQLITE_ERROR ){
@@ -2624,7 +2648,7 @@ static void recoverStep(sqlite3_recover *p){
           if( bUseWrapper ) recoverUninstallWrapper(p);
         }while( p->errCode==SQLITE_NOTADB 
              && (bUseWrapper--) 
-             && SQLITE_OK==sqlite3_exec(p->dbIn, "ROLLBACK", 0, 0, 0)
+             && SQLITE_OK==recoverOneStmt(p->dbIn, "ROLLBACK")
         );
       }
 
@@ -2689,7 +2713,7 @@ static void recoverStep(sqlite3_recover *p){
       ** database. Regardless of whether or not an error has occurred, make
       ** an attempt to end the read transaction on the input database.  */
       recoverExec(p, p->dbOut, "COMMIT");
-      rc = sqlite3_exec(p->dbIn, "END", 0, 0, 0);
+      rc = recoverOneStmt(p->dbIn, "END");
       if( p->errCode==SQLITE_OK ) p->errCode = rc;
 
       recoverSqlCallback(p, "PRAGMA writable_schema = off");
@@ -2885,7 +2909,7 @@ int sqlite3_recover_finish(sqlite3_recover *p){
   }else{
     recoverFinalCleanup(p);
     if( p->bCloseTransaction && sqlite3_get_autocommit(p->dbIn)==0 ){
-      rc = sqlite3_exec(p->dbIn, "END", 0, 0, 0);
+      rc = recoverOneStmt(p->dbIn, "END");
       if( p->errCode==SQLITE_OK ) p->errCode = rc;
     }
     rc = p->errCode;

manifest

@@ -1,5 +1,5 @@
-C Fix\sa\scrash\sthat\scould\soccur\sif\ssqlite3_deserialize()\swas\sused\sto\soverwrite\sa\sdatabase\swith\san\sopen\stransaction\son\sit.\sBug\sintroduced\sby\s[fc42d31d6fca21ab]\son\s2018-03-07\sand\sfirst\sreleased\sin\sversion\s3.23.0.\sThis\sis\snot\sa\svulnerability\sas\san\sattacker\sthat\scan\sexploit\sthis\salready\shas\sthe\sability\sto\sexecute\sarbitrary\scode.\sForum\spost\s[forum:39134ba029\s|\s39134ba029].
-D 2026-04-27T12:28:23.589
+C Harden\sthe\srecovery\sextension\sagainst\sSQL\sinjections\scoming\sfrom\sthe\nsqlite_schema\stable\sof\sthe\sdatabase\sbeing\srecovered.
+D 2026-05-01T13:56:19.868
 F .fossil-settings/binary-glob 61195414528fb3ea9693577e1980230d78a1f8b0a54c78cf1b9b24d0a409ed6a x
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
@@ -486,7 +486,7 @@ F ext/recover/recoverpgsz.test 88766fcb810e52ee05335c456d4e5fb06d02b73d3ccb48c52
 F ext/recover/recoverrowid.test f948bf4024a5f41b0e21b8af80c60564c5b5d78c05a8d64fc00787715ff9f45f
 F ext/recover/recoverslowidx.test c90d59c46bb8924a973ac6fbc38f3163cee38cc240256addcab1cf1a322c37dc
 F ext/recover/recoversql.test e66d01f95302a223bcd3fd42b5ee58dc2b53d70afa90b0d00e41e4b8eab20486
-F ext/recover/sqlite3recover.c 56c216332ea91233d6d820d429f3384adbec9ecedda67aa98186b691d427cc57
+F ext/recover/sqlite3recover.c dfbfca5a8e4909333e5aa3749bcffb5dd7e396de9541c338f8cc843b2e20217e
 F ext/recover/sqlite3recover.h 011c799f02deb70ab685916f6f538e6bb32c4e0025e79bfd0e24ff9c74820959
 F ext/recover/test_recover.c 3d0fb1df7823f5bc22a0b93955034d16a2dfa2eb1e443e9a0123a77f120599a3
 F ext/rtree/README 734aa36238bcd2dee91db5dba107d5fcbdb02396612811377a8ad50f1272b1c1
@@ -2197,9 +2197,8 @@ F tool/warnings-clang.sh bbf6a1e685e534c92ec2bfba5b1745f34fb6f0bc2a362850723a9ee
 F tool/warnings.sh a554d13f6e5cf3760f041b87939e3d616ec6961859c3245e8ef701d1eafc2ca2
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
 F tool/winmain.c 00c8fb88e365c9017db14c73d3c78af62194d9644feaf60e220ab0f411f3604c
-P e3f318bf52932460890333c6dcae352ab4b0c943d7be67734649eff1ff9fc9fc
-Q +77662cce9aa452ba5820e5f1a864a802763bd83b937cdb16e7025219eff7bd08
-R 13f45488f2adbf7d8419fcbad47e0b59
+P b7b0745d6def6b141c900884cd97f10f3afedcbfb4bd9ce2409ee2380a8602dd
+R 11219c7cfe7bdcf239f28e0e5affe87f
 U drh
-Z 52f7987a045aaf068eaa89a2ec557d9d
+Z 6e7e7042c5556e0b59775c06541d4c66
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-b7b0745d6def6b141c900884cd97f10f3afedcbfb4bd9ce2409ee2380a8602dd
+555401fe048a51ecaed3ef672723b6ef8e1340c7028c11a17731abbc399bc078