Failed Bad Packets false positive fully restricts player movement on all mc versions below 1.17

MithrandirCraft commented 9 months ago

Describe the false positive and how to replicate it

Just install grimac on a clean paper server with viaversion, viarewind (and optionally viabackwards), then connect to the server using a client version below 1.17 (that is 1.16.2 or lower).

If you're an admin you should notice the Bad Packets false positive messages in chat.

PadPackets check should either be adjusted for clients below 1.17, disabled, or there should be a workaround.

imagen

Grim version

2.3.55

Server version

1.20.2 (with all via* plugins installed)

Plugins

Server Plugins (50): Paper Plugins:

AuthMeVelocity, MarriageMaster Bukkit Plugins:
40ServidoresMC, AdvancedPortals, AuthMe, BanFromClaim, BetterRTP, BottledExp, ChatControlRed, ClearLag, CMILib, CoreProtect CraftingStore, CrazyCrates, CustomJukebox, DecentHolograms, DownloadResourcePack, ElytraBalance, Essentials, EssentialsSpawn, FastAsyncWorldEdit, FastLogin floodgate, GriefDefender, GrimAC, Guilds, JukeboxRegion, LibsDisguises, LuckPerms, MythicMobs, NerfVillages, PlaceholderAPI PlayerHeads, PlayerWarps, PremiumVanish, ProtocolLib, Shopkeepers, SkinsRestorer, SSX-Connector, *StatsPvP, Storage, TAB-Bridge TradeSystem, Vault, ViaBackwards, ViaRewind, ViaVersion, ViewDistanceTweaks, VotingPlugin, WorldGuard

SamB440 commented 9 months ago

BadPacketsN means you are ignoring teleports. Please try and reproduce with only GrimAC and via installed.

MithrandirCraft commented 9 months ago

It's happening only on my survival server with only grimac, ViaBackwards, ViaRewind & ViaVersion installed.

It's likely to be server/config related, but I still haven't pinpointed what.

What is this teleportation ignore you mention? Maybe a server config?

SamB440 commented 9 months ago

I am saying that BadPacketsN flags because Grim believes your client has ignored a teleport packet.

I can't reproduce this problem with a 1.20.2 Paper server and a 1.12.2 vanilla client.

MithrandirCraft commented 9 months ago

Just noticed it actually does happen on every server on my network, velocity related?

MithrandirCraft commented 9 months ago

Fixed: Issue was I had left the via* plugins on velocity, as well as on every backend server.

Big fail.

SamB440 commented 8 months ago

Please close this issue, then

GrimAnticheat / Grim