Apply the 5.6.40 security fixes to XtraDB

We did not merge Percona XtraDB 5.6.40-84.0 yet.
The changes in it are mostly cosmetic, except for
2 bug fixes from Oracle MySQL 5.6.40, which could
be security bugs.

This was achieved by taking the applicable parts
of an earlier InnoDB commit to XtraDB:

git diff 15ec8c2{~,} storage/innobase|
sed -e s+/innobase/+/xtradb/+|patch -p1

storage/xtradb/handler/handler0alter.cc

@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-Copyright (c) 2005, 2017, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2005, 2018, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2017, 2018, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
@@ -4782,37 +4782,44 @@ innobase_rename_columns_cache(
 }
 
 /** Get the auto-increment value of the table on commit.
-@param ha_alter_info	Data used during in-place alter
-@param ctx		In-place ALTER TABLE context
-@param altered_table	MySQL table that is being altered
-@param old_table	MySQL table as it is before the ALTER operation
-@return the next auto-increment value (0 if not present) */
+@param[in] ha_alter_info	Data used during in-place alter
+@param[in,out] ctx		In-place ALTER TABLE context
+				return autoinc value in ctx->max_autoinc
+@param altered_table[in]	MySQL table that is being altered
+@param old_table[in]	MySQL table as it is before the ALTER operation
+retval true Failure
+@retval false Success*/
 static MY_ATTRIBUTE((nonnull, warn_unused_result))
-ulonglong
+bool
 commit_get_autoinc(
 /*===============*/
 	Alter_inplace_info*	ha_alter_info,
 	ha_innobase_inplace_ctx*ctx,
 	const TABLE*		altered_table,
 	const TABLE*		old_table)
 {
-	ulonglong		max_autoinc;
 
 	DBUG_ENTER("commit_get_autoinc");
 
 	if (!altered_table->found_next_number_field) {
 		/* There is no AUTO_INCREMENT column in the table
 		after the ALTER operation. */
-		max_autoinc = 0;
+		ctx->max_autoinc = 0;
 	} else if (ctx->add_autoinc != ULINT_UNDEFINED) {
 		/* An AUTO_INCREMENT column was added. Get the last
 		value from the sequence, which may be based on a
 		supplied AUTO_INCREMENT value. */
-		max_autoinc = ctx->sequence.last();
+		ctx->max_autoinc = ctx->sequence.last();
 	} else if ((ha_alter_info->handler_flags
 		    & Alter_inplace_info::CHANGE_CREATE_OPTION)
 		   && (ha_alter_info->create_info->used_fields
 		       & HA_CREATE_USED_AUTO)) {
+
+		/* Check if the table is discarded */
+		if(dict_table_is_discarded(ctx->old_table)) {
+			DBUG_RETURN(true);
+		}
+
 		/* An AUTO_INCREMENT value was supplied, but the table was not
 		rebuilt. Get the user-supplied value or the last value from the
 		sequence. */
@@ -4827,7 +4834,8 @@ commit_get_autoinc(
 		dict_index_t*	index = dict_table_get_index_on_name(
 			ctx->old_table, autoinc_key->name);
 
-		max_autoinc = ha_alter_info->create_info->auto_increment_value;
+		ctx->max_autoinc =
+			ha_alter_info->create_info->auto_increment_value;
 
 		dict_table_autoinc_lock(ctx->old_table);
 
@@ -4836,16 +4844,16 @@ commit_get_autoinc(
 
 		if (err != DB_SUCCESS) {
 			ut_ad(0);
-			max_autoinc = 0;
-		} else if (max_autoinc <= max_value_table) {
+			ctx->max_autoinc = 0;
+		} else if (ctx->max_autoinc <= max_value_table) {
 			ulonglong	col_max_value;
 			ulonglong	offset;
 
 			col_max_value = innobase_get_int_col_max_value(
 				old_table->found_next_number_field);
 
 			offset = ctx->prebuilt->autoinc_offset;
-			max_autoinc = innobase_next_autoinc(
+			ctx->max_autoinc = innobase_next_autoinc(
 				max_value_table, 1, 1, offset,
 				col_max_value);
 		}
@@ -4855,11 +4863,11 @@ commit_get_autoinc(
 		Read the old counter value from the table. */
 		ut_ad(old_table->found_next_number_field);
 		dict_table_autoinc_lock(ctx->old_table);
-		max_autoinc = ctx->old_table->autoinc;
+		ctx->max_autoinc = ctx->old_table->autoinc;
 		dict_table_autoinc_unlock(ctx->old_table);
 	}
 
-	DBUG_RETURN(max_autoinc);
+	DBUG_RETURN(false);
 }
 
 /** Add or drop foreign key constraints to the data dictionary tables,
@@ -5828,8 +5836,13 @@ ha_innobase::commit_inplace_alter_table(
 
 		DBUG_ASSERT(new_clustered == ctx->need_rebuild());
 
-		ctx->max_autoinc = commit_get_autoinc(
-			ha_alter_info, ctx, altered_table, table);
+		if (commit_get_autoinc(ha_alter_info, ctx, altered_table,
+			table)) {
+			fail = true;
+			my_error(ER_TABLESPACE_DISCARDED, MYF(0),
+				 table->s->table_name.str);
+			goto rollback_trx;
+		}
 
 		if (ctx->need_rebuild()) {
 			ctx->tmp_name = dict_mem_create_temporary_tablename(
@@ -5861,6 +5874,8 @@ ha_innobase::commit_inplace_alter_table(
 #endif
 	}
 
+rollback_trx:
+
 	/* Commit or roll back the changes to the data dictionary. */
 
 	if (fail) {

storage/xtradb/row/row0log.cc

@@ -1,6 +1,6 @@
 /*****************************************************************************
 
-Copyright (c) 2011, 2016, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2011, 2018, Oracle and/or its affiliates. All Rights Reserved.
 Copyright (c) 2017, 2018, MariaDB Corporation.
 
 This program is free software; you can redistribute it and/or modify it under
@@ -2631,7 +2631,15 @@ row_log_table_apply_ops(
 
 	while (!trx_is_interrupted(trx)) {
 		mrec = next_mrec;
-		ut_ad(mrec < mrec_end);
+		ut_ad(mrec <= mrec_end);
+
+		if (mrec == mrec_end) {
+			/* We are at the end of the log.
+			   Mark the replay all_done. */
+			if (has_index_lock) {
+				goto all_done;
+			}
+		}
 
 		if (!has_index_lock) {
 			/* We are applying operations from a different