[MCOL-5535] Wrong permission of /dev/shm Created: 2023-07-18  Updated: 2023-09-22  Resolved: 2023-08-18

Status: Closed
Project: MariaDB ColumnStore
Component/s: None
Affects Version/s: 22.08.8, 6.4.7- CS only, 23.02.4
Fix Version/s: 23.10.0

Type: Bug Priority: Minor
Reporter: Petr Procházka Assignee: Roman
Resolution: Fixed Votes: 0
Labels: None
Environment:

VirtualBox v7.0.8
openSUSE Thumbleweed: Linux Thumbleweed 6.4.2-1-default #1 SMP PREEMPT_DYNAMIC Mon Jul 10 10:03:25 UTC 2023 (b97b894) x86_64 x86_64 x86_64 GNU/Linux

MariaDB ColumnStore v10.11.4_6.4.7 as single node installation.


Sprint: 2023-8

 Description   

After installation or restart of service is broken permissions for /dev/shm directory.

  • This is state before install:

    Thumbleweed:~ # l /dev/shm/
    total 1052
    drwxrwxrwt  2 root     root          80 Jul 18 13:06 ./
    drwxr-xr-x 18 root     root        4120 Jul 18 13:06 ../
    -rw-------  1 postgres postgres   26976 Jul 18 13:06 PostgreSQL.3071437720
    -rw-------  1 postgres postgres 1048576 Jul 18 13:06 PostgreSQL.3800041244
    

  • This is state after install:

    Thumbleweed:~ # l /dev/shm/
    total 8532
    drwxrwxrwx  2 root     root          320 Jul 18 13:09 ./
    drwxr-xr-x 18 root     root         4120 Jul 18 13:06 ../
    -rw-rw-rw-  1 mysql    mysql         112 Jul 18 13:09 MCS-shm-00010000
    -rw-rw-rw-  1 mysql    mysql     5000020 Jul 18 13:09 MCS-shm-00010002
    -rw-rw-rw-  1 mysql    mysql         112 Jul 18 13:09 MCS-shm-00020000
    -rw-rw-rw-  1 mysql    mysql       96000 Jul 18 13:09 MCS-shm-00020001
    -rw-rw-rw-  1 mysql    mysql         112 Jul 18 13:09 MCS-shm-00030000
    -rw-rw-rw-  1 mysql    mysql         800 Jul 18 13:09 MCS-shm-00030001
    -rw-rw-rw-  1 mysql    mysql         112 Jul 18 13:09 MCS-shm-00040000
    -rw-rw-rw-  1 mysql    mysql     2500020 Jul 18 13:09 MCS-shm-00040002
    -rw-rw-rw-  1 mysql    mysql         112 Jul 18 13:09 MCS-shm-00050000
    -rw-rw-rw-  1 mysql    mysql         112 Jul 18 13:09 MCS-shm-00060000
    -rw-rw-rw-  1 mysql    mysql    16777216 Jul 18 13:09 MCS-shm-00060001
    -rw-rw-rw-  1 mysql    mysql          72 Jul 18 13:09 MCS-shm-ff000000
    -rw-------  1 postgres postgres    26976 Jul 18 13:06 PostgreSQL.3071437720
    -rw-------  1 postgres postgres  1048576 Jul 18 13:06 PostgreSQL.3800041244
    

  • This is state after restart service mariadb-columnstore:

    Thumbleweed:~ # service mariadb-columnstore restart
    Thumbleweed:~ # l /dev/shm/
    total 8536
    drwxrwxrwx  2 root  root       340 Jul 18 13:09 ./
    drwxr-xr-x 18 root  root      4120 Jul 18 13:06 ../
    -rw-rw-rw-  1 mysql mysql      112 Jul 18 13:09 MCS-shm-00010000
    -rw-rw-rw-  1 mysql mysql  5000020 Jul 18 13:09 MCS-shm-00010003
    -rw-rw-rw-  1 mysql mysql      112 Jul 18 13:09 MCS-shm-00020000
    -rw-rw-rw-  1 mysql mysql    96000 Jul 18 13:09 MCS-shm-00020001
    -rw-rw-rw-  1 mysql mysql      112 Jul 18 13:09 MCS-shm-00030000
    -rw-rw-rw-  1 mysql mysql      800 Jul 18 13:09 MCS-shm-00030001
    -rw-rw-rw-  1 mysql mysql      112 Jul 18 13:09 MCS-shm-00040000
    -rw-rw-rw-  1 mysql mysql  2500020 Jul 18 13:09 MCS-shm-00040004
    -rw-rw-rw-  1 mysql mysql      112 Jul 18 13:09 MCS-shm-00050000
    -rw-rw-rw-  1 mysql mysql      112 Jul 18 13:09 MCS-shm-00060000
    -rw-rw-rw-  1 mysql mysql 16777216 Jul 18 13:09 MCS-shm-00060001
    -rw-rw-rw-  1 mysql mysql       40 Jul 18 13:09 MCS-shm-f7000000
    -rw-rw-rw-  1 mysql mysql       72 Jul 18 13:09 MCS-shm-ff000000
    -rw-------  1 mysql mysql    26976 Jul 18 13:06 PostgreSQL.3071437720
    -rw-------  1 mysql mysql  1048576 Jul 18 13:06 PostgreSQL.3800041244
    

I found that permissions change this Python script: /usr/bin/mcs-loadbrm.py.
So as workaround I locally modify this script and remove set permissions for all files in script (lines).



 Comments   
Comment by Roman [ 2023-08-07 ]

Hi petr.prochazka.
Thx for the bug report. We will surely fix this very "optimistic" assumtion that all shm files belongs to MCS.

Comment by Roman [ 2023-08-09 ]

I made a commit to fix this.

Comment by Daniel Lee (Inactive) [ 2023-08-18 ]

Build verified: develop branch, latest

engine: 765dd46b61334c750c6fa5e5f22e9761950ec29d
server: e9345305497f951b2e612ba11cb8e79affa0c844
buildNo: 8451

Reproduced the issue in release 23.02.4 and verified the fix.

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