Some fixes and improvements

[lem21h]

Community Contribution License

All community contributions in this pull request are licensed to the project maintainers
under the terms of the Apache 2 license.
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contributions to the project maintainers under the Apache 2 license.

Description

General set of updates to prevent code panic due to some cases.
Added some improvements to reduce amount of created GoRoutines in some functions - more work needed

Motivation and Context

Want to make this project better and readable

How to test this PR?

Just run the tests

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Optimization (provides speedup with no functional changes)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• Fixes a regression (If yes, please add commit-id or PR # here)
• Unit tests added/updated
• Internal documentation updated
• Create a documentation update request here

[lem21h]

I'm sorry for poking - but is there a change someone could have a look into that (for example @Vonng

I have a bit more things I would like to "improve" and fix

[Vonng]

Thanks for the work here. This PR is too large and mixed for us to review or merge as-is 😂. For this fork, we try to keep changes narrowly scoped to security fixes and clearly auditable hardening work. I do see two parts that are worth splitting into focused PRs:

1. Harden ReadParts / DeleteBulk by validating paths from the msgpack request body.
2. Harden metacache marker parsing so malformed markers cannot panic or mutate state before validation.

Those two would be much easier to review and are aligned with the project scope.

[lem21h]

Thank you @Vonng for feedback - I will try to split this up - I have some more things already done

also I've identified a lot of race conditions - which we, in my work, experience under a heavy load in Minio, so still digging to resolve those issues too

[lem21h]

@Vonng reduced to "cosmetic" changes