Greenmask V0.1.13 SIGSEGV

[TCY16]

Hi!

While using Greenmask for the first time, I've encountered a segfault. Using the dump option while testing on a single table in my database. I've verified connection with psql following config:

dump:
  pg_dump_options:
    dbname: "host=obfuscated-amazon-address user=postgres dbname=db_name"
    jobs: 10
    table: "tablename"
storage:
  type: "directory"
  directory:
    path: "/home/ssm-user/tmp"

The segfault output is:

panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x20 pc=0xd3ddb1]

goroutine 151 [running]:
github.com/jackc/pgx/v5.(*LargeObject).Close(...)
	/home/runner/go/pkg/mod/github.com/jackc/pgx/[email protected]/large_objects.go:156
github.com/greenmaskio/greenmask/internal/db/postgres/dumpers.(*BlobsDumper).Execute.func2.2()
	/home/runner/work/greenmask/greenmask/internal/db/postgres/dumpers/large_object.go:95 +0x31
github.com/greenmaskio/greenmask/internal/db/postgres/dumpers.(*BlobsDumper).Execute.func2()
	/home/runner/work/greenmask/greenmask/internal/db/postgres/dumpers/large_object.go:100 +0x1f1
golang.org/x/sync/errgroup.(*Group).Go.func1()
	/home/runner/go/pkg/mod/golang.org/x/[email protected]/errgroup/errgroup.go:78 +0x56
created by golang.org/x/sync/errgroup.(*Group).Go in goroutine 65
	/home/runner/go/pkg/mod/golang.org/x/[email protected]/errgroup/errgroup.go:75 +0x96

For completeness; The uname -r output gives: 6.1.79-99.167.amzn2023.x86_64. I've used greenmask-linux-amd64.tar.gz and the following libraries postgresql15 postgresql15-contrib. The database version is Postgres 15 as well.

On a different note, I've also found that greenmask dump --data-only gives a schema collision error : "pg_dump: error: options -s/--schema-only and -a/--data-only cannot be used together"

[wwoytenko]

Hi! Thank you for reporting!

github.com/greenmaskio/greenmask/internal/db/postgres/dumpers.(*BlobsDumper).Execute.func2.2()

Looks like the seg fault is in Large Object dumping. I will check this tomorrow. There is definitely a bug.

On a different note, I've also found that greenmask dump --data-only gives a schema collision error : "pg_dump: error: options -s/--schema-only and -a/--data-only cannot be used together"

Well, you're right. I will review this case tomorrow as well.

[wwoytenko]

I've created #103 PR, but I will review the logic. I think there might be high resource utilization without a worker pool pattern. I will keep you posted

[wwoytenko]

@TCY16

The large object dumper seg fault I hope will be fixed in #103

The fix is expected to be published as v0.1.14 on Thursday (09.05.2024)

Regarding this

On a different note, I've also found that greenmask dump --data-only gives a schema collision error : "pg_dump: error: options -s/--schema-only and -a/--data-only cannot be used together"

I've opened issue #104 and initialized a PR #105

[wwoytenko]

Regarding --data-only workaround right now

I recommend creating dump as usual without --data-only.

But if you need to restore only data you can call restore --data-only.

[TCY16]

Thanks for the super quick turnaround! I'll post more issues if they come up 😄

[wwoytenko]

Published in 0.1.14. Let me know if everything is ok