MDEV-26933 InnoDB fails to detect page number mismatch

mtr_t::page_lock(): Validate the page number.

ibuf_tree_root_get(): Remove assertions that became redundant.

The assertions in btr_validate_level() are kind of redundant as well,
but because they are ut_a(), they are also present in release builds,
while the ones in mtr_t::page_lock() are only present in debug builds.

btr_cur_position(): Do not duplicate an assertion that is part of
page_cur_position().

dict_load_tablespace(): Introduce a new option
DICT_ERR_IGNORE_TABLESPACE that will suppress loading a tablespace
when a table is going to be dropped.

Author: dr-m

mysql-test/suite/innodb/r/alter_kill.result

@@ -11,7 +11,7 @@ InnoDB		0 transactions not purged
 connection default;
 # Cleanly shutdown mysqld
 disconnect con1;
-# Corrupt FIL_PAGE_OFFSET in bug16720368.ibd,
+# Corrupt FIL_PAGE_TYPE in bug16720368.ibd,
 # and recompute innodb_checksum_algorithm=crc32
 # restart
 SELECT COUNT(*) FROM bug16720368;

mysql-test/suite/innodb/t/alter_kill.test

@@ -43,7 +43,7 @@ connection default;
 
 disconnect con1;
 
--- echo # Corrupt FIL_PAGE_OFFSET in bug16720368.ibd,
+-- echo # Corrupt FIL_PAGE_TYPE in bug16720368.ibd,
 -- echo # and recompute innodb_checksum_algorithm=crc32
 perl;
 do "$ENV{MTR_SUITE_DIR}/include/crc32.pl";
@@ -56,7 +56,7 @@ die "Unable to read $file" unless sysread(FILE, $page, $ps) == $ps;
 my $full_crc32 = unpack("N",substr($page,54,4)) & 0x10; # FIL_SPACE_FLAGS
 sysseek(FILE, 3*$ps, 0) || die "Unable to seek $file\n";
 die "Unable to read $file" unless sysread(FILE, $page, $ps) == $ps;
-substr($page,4,4)=pack("N",0xc001cafe);
+substr($page,24,2)='42';
 my $polynomial = 0x82f63b78; # CRC-32C
 if ($full_crc32)
 {
@@ -86,7 +86,7 @@ INSERT INTO bug16720368_1 VALUES(1);
 -- echo # Shut down the server to uncorrupt the data.
 -- source include/shutdown_mysqld.inc
 
-# Uncorrupt the FIL_PAGE_OFFSET.
+# Uncorrupt the FIL_PAGE_TYPE.
 perl;
 do "$ENV{MTR_SUITE_DIR}/include/crc32.pl";
 my $file = "$ENV{MYSQLD_DATADIR}/test/bug16720368.ibd";
@@ -98,7 +98,7 @@ die "Unable to read $file" unless sysread(FILE, $page, $ps) == $ps;
 my $full_crc32 = unpack("N",substr($page,54,4)) & 0x10; # FIL_SPACE_FLAGS
 sysseek(FILE, 3*$ps, 0) || die "Unable to seek $file\n";
 die "Unable to read $file" unless sysread(FILE, $page, $ps) == $ps;
-substr($page,4,4)=pack("N",3);
+substr($page,24,2)=pack("H*","45BF");
 my $polynomial = 0x82f63b78; # CRC-32C
 if ($full_crc32)
 {

mysql-test/suite/innodb/t/log_corruption.test

@@ -57,7 +57,14 @@ my $body = pack("x[8]Nx[10]Nx[16312]", 768, 97937874);
 my $ck = mycrc32($head, 0, $polynomial) ^ mycrc32($body, 0, $polynomial);
 print OUT pack("N",$ck).$head.pack("x[12]").$body.pack("Nx[4]",$ck);
 # Dummy pages 1..6.
-print OUT chr(0) x (6 * 16384);
+$body = pack("x[16338]");
+for (my($page) = 1; $page < 7; $page++)
+{
+    ## FIL_PAGE_OFFSET
+    $head = pack("Nx[18]", $page);
+    $ck = mycrc32($head, 0, $polynomial) ^ mycrc32($body, 0, $polynomial);
+    print OUT pack("N",$ck).$head.pack("x[16350]Nx[4]",$ck);
+}
 # Dictionary header page (page 7).
 ## FIL_PAGE_OFFSET
 $head = pack("Nx[18]", 7);

mysql-test/suite/innodb/t/page_id_innochecksum.test

@@ -61,5 +61,9 @@ let SEARCH_PATTERN=page id mismatch;
 --source include/search_pattern_in_file.inc
 
 --remove_file $resultlog
+# prevent purge from crashing on page ID mismatch
+let $restart_parameters=--innodb-force-recovery=2;
 --source include/start_mysqld.inc
 drop table t1;
+let $restart_parameters=;
+--source include/restart_mysqld.inc

storage/innobase/dict/dict0crea.cc

@@ -654,7 +654,7 @@ dict_build_index_def_step(
 	index = node->index;
 
 	table = dict_table_open_on_name(
-		node->table_name, true, DICT_ERR_IGNORE_DROP);
+		node->table_name, true, DICT_ERR_IGNORE_TABLESPACE);
 
 	if (!table) {
 		return DB_TABLE_NOT_FOUND;

storage/innobase/dict/dict0load.cc

@@ -2225,7 +2225,7 @@ dict_load_tablespace(
 		return;
 	}
 
-	if (ignore_err == DICT_ERR_IGNORE_DROP) {
+	if (ignore_err >= DICT_ERR_IGNORE_TABLESPACE) {
 		table->file_unreadable = true;
 		return;
 	}
@@ -2412,6 +2412,11 @@ static dict_table_t *dict_load_table_one(const span<const char> &name,
 			table->corrupted = true;
 			table->file_unreadable = true;
 			err = DB_CORRUPTION;
+		} else if (table->space->id
+			   && ignore_err == DICT_ERR_IGNORE_DROP) {
+			/* Do not bother to load data from .ibd files
+			only to delete the .ibd files. */
+			goto corrupted;
 		} else {
 			const page_id_t page_id(table->space->id, root);
 			mtr.start();

storage/innobase/fts/fts0fts.cc

@@ -1373,7 +1373,7 @@ fts_cache_add_doc(
 static dberr_t fts_drop_table(trx_t *trx, const char *table_name, bool rename)
 {
   if (dict_table_t *table= dict_table_open_on_name(table_name, true,
-                                                   DICT_ERR_IGNORE_DROP))
+                                                   DICT_ERR_IGNORE_TABLESPACE))
   {
     table->release();
     if (rename)
@@ -1505,7 +1505,7 @@ static dberr_t fts_lock_table(trx_t *trx, const char *table_name)
   ut_ad(purge_sys.must_wait_FTS());
 
   if (dict_table_t *table= dict_table_open_on_name(table_name, false,
-                                                   DICT_ERR_IGNORE_DROP))
+                                                   DICT_ERR_IGNORE_TABLESPACE))
   {
     dberr_t err= lock_table_for_trx(table, trx, LOCK_X);
     /* Wait for purge threads to stop using the table. */

storage/innobase/ibuf/ibuf0ibuf.cc

@@ -341,8 +341,6 @@ static buf_block_t *ibuf_tree_root_get(mtr_t *mtr)
 		page_id_t(IBUF_SPACE_ID, FSP_IBUF_TREE_ROOT_PAGE_NO),
 		0, RW_SX_LATCH, mtr);
 
-	ut_ad(page_get_space_id(block->frame) == IBUF_SPACE_ID);
-	ut_ad(page_get_page_no(block->frame) == FSP_IBUF_TREE_ROOT_PAGE_NO);
 	ut_ad(ibuf.empty == page_is_empty(block->frame));
 
 	return block;

storage/innobase/include/btr0cur.ic

@@ -1,7 +1,7 @@
 /*****************************************************************************
 
 Copyright (c) 1994, 2015, Oracle and/or its affiliates. All Rights Reserved.
-Copyright (c) 2018, 2020, MariaDB Corporation.
+Copyright (c) 2018, 2021, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
 the terms of the GNU General Public License as published by the Free Software
@@ -109,10 +109,7 @@ btr_cur_position(
 	buf_block_t*	block,	/*!< in: buffer block of rec */
 	btr_cur_t*	cursor)	/*!< out: cursor */
 {
-	ut_ad(page_align(rec) == block->frame);
-
 	page_cur_position(rec, block, btr_cur_get_page_cur(cursor));
-
 	cursor->index = index;
 }
 

storage/innobase/include/dict0types.h

@@ -82,8 +82,12 @@ enum dict_err_ignore_t {
 					incomplete index definitions. */
 	/** ignore all errors above */
 	DICT_ERR_IGNORE_ALL = 15,
-	/** prepare to drop the table; do not attempt to load tablespace */
-	DICT_ERR_IGNORE_DROP = 31
+	/** prepare some DDL operation;
+	do not attempt to load tablespace */
+	DICT_ERR_IGNORE_TABLESPACE = 31,
+	/** prepare to drop the table; do not attempt to load tablespace
+	or the metadata */
+	DICT_ERR_IGNORE_DROP = 63
 };
 
 /** Quiescing states for flushing tables to disk. */