[MDEV-29103] Aria Table Data Loss Created: 2022-07-14  Updated: 2023-11-28

Status: Confirmed
Project: MariaDB Server
Component/s: Encryption, Storage Engine - Aria
Affects Version/s: 10.3, 10.4, 10.5, 10.6, 10.7, 10.8, 10.9, 10.10
Fix Version/s: 10.4, 10.5, 10.6

Type: Bug Priority: Critical
Reporter: Chris Haddon Assignee: Sergei Golubchik
Resolution: Unresolved Votes: 0
Labels: Aria, Windows, data-loss, encryption, repair, use_frm
Environment:

Reproduced on Windows 10 and Windows Server 2016

Attachments: Zip Archive HEDOHWBSVRTTAPP.zip    

 Description   

I have found a critical bug in Aria (Page storage format) where tables are wiped if someone runs a repair command with the USE_FRM flag.

REPAIR TABLE X USE_FRM

This bug only exists for databases that use an encryption plugin. In our case we use a file encryption plugin, however it is likely this bug affects all types of encryption plugin.

Disabling the encryption plugin or changing the storage format to Dynamic will prevent the USE_FRM from wiping the table.

However, since we require Data Encryption at Rest, we have to use encryption and Page storage format.

To reproduce, set up a Windows VM with MariaDB 10.5.13 (or later) installed.
Load on a file-based encryption plugin (or any other encryption plugin).

Then create a database and some tables and add data.
Finally, run a repair table command with the additional flag USE_FRM.

Now disconnect and reconnect to the Database and you will see all data has been removed.

A proposed dirty fix could be the following:
If table type is Aria and Storage Format is Page and encryption is enabled, then ignore USE_FRM flag if its passed in.

 Comments   
Comment by Chris Haddon [ 2022-07-15 ]

There also seems to be the same issue with auto-recovery when using encryption. Is it possible auto-recovery also uses USE_FRM ? If so, this might need fixing/tweaking so that USE_FRM isn't used.

Comment by Chris Haddon [ 2022-07-21 ]

We just had a power cut at one of our sites.
Before the power cut the system was functioning correctly.
After the power cut, the database "tigersys" had been wiped.

I believe this is related to auto crash recovery built into Aria when
using encryption plugins.

Please see attached mariadb err log (zipped up).

Comment by Elena Stepanova [ 2022-07-25 ]

Thanks for the report. Reproducible as described.

--source suite/encryption/include/have_file_key_management_plugin.inc
 
 
 
set global aria_encrypt_tables=1;
 
 
 
create table t (a int) engine=Aria row_format=PAGE;
 
insert into t values (1),(2);
 
repair table t use_frm;
 
select * from t;
 
 
 
# Cleanup
 
drop table t;
 
set global aria_encrypt_tables= default;

10.3 02e85aea

 
repair table t use_frm;
 
Table	Op	Msg_type	Msg_text
 
test.t	repair	info	Wrong CRC on datapage at 1
 
test.t	repair	status	OK
 
select * from t;
 
a
 
drop table t;

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