Giving items with unknown (high) data value crashes and leaves the world unusable

I will tell you if you get above 8 (and it seems mostly any numbers above 8 up to at least 11) will spawn in the upper half of the flower, taking the form of whatever flower is under it. From what I can see, 6 and 7 crash it (and in my case, rendered one of my worlds unloadable). But yea, if there is a command that can be put it, it shouldn't cause an outright crash but instead an error message in the chat.

This is... quite exploitable, to say the least.

I fail to see how world corruption is the "intended" consequence of using a command. A player may have made a typo (for example, 135:6 wouldn't cause any issues). Besides, obtaining the item via /give will also cause crashes and world corruption. When players reported that wool blocks with damage values above 15 caused crashes, Mojang actually addressed it, and fixed the bug. I don't see why this situation would be intended, if that one wasn't.

Actually, just to clarify here, as this ticket neglects to mention something important:

This bug can be performed in the vanilla client, with no external tools, via commands such as "/setblock ~ ~ ~ 175 6" and "/give @p 175 1 6". That's what I mean by "exploitable" - although it's a given that a player with OP commands should be able to mess up a world pretty badly, creating a redstone contraption which corrupts the server is just a bit much.

I think Mod Anon Ymus wasn't aware that this bug can be performed in-game using simple commands. Is that correct?

No, I was aware, but I feel that messing with blocks that aren't obtainable without purposely /give-ing them to yourself should not be expected to work. Either way, I'll reopen this issue. Mojang can decide what they want done about it.

Yeah, this is annoying, but indeed data value 6 and 7 crash the game, 8 and up spawn the upper halves of the flowers. Hope this helped

This is a solution for those needing to fix their Minecraft world when 175:6 is crashing the world
-Download MCEdit
-Run MCEdit for the world
-Create a custom chest (must be a premade chest)
-Add item id 175 and damage value 6
-Click: Remove id from entire world
-tick the box that only deletes the item/block with the damage value
It should fix the problem, if game crashes again, then simply reload the world again.

Just had this happen to me. Very annoying to revert to a backup (only 1 day old thank god). Note that the object is in the players inventory and changing it doesn't help (the game still tries to load it as the old value, presumably only honoring the change in the second game tick), although I have a different editor than suggested. Surprised griefers aren't nuking worlds with this (although I guess you'd need permission to use give commands first).

If it's a singleplayer world, you should be editing the level.dat's copy of the player, not your named file in the players folder (changes are ignored to that in singleplayer). If you did /setblock, you'll need to use MCedit to get rid of it.

Yeah I did and it didn't help. No I didn't use setblock, it was "give". I can see the item in slot 4 and change it's damage number and item id but the game still tries to render the old value. I didn't lose very much at all so I'm just cutting my losses. I'm more worried about the fact that they have no intention of fixing it. This could make for some pretty high level griefing on multiplayer, granted they couldn't corrupt the map without access to the give command. Some servers have more levels of permissions than just "full op or nothing" though.

Perhaps the bug is not the value crashing the game, but it is Minecraft not recognizing that the metadata values of 6 and 7 are invalid.

Normally Mojang puts dupes in the slots (like with Log2 (block 162)). If they'd just made 6 and 7 dupes of 0 and 1 it wouldn't be a problem.

This is really becoming a big problem on my server where I let users use the /item command.

That command doesn't exist in Minecraft, so it cannot be fixed.

I have found a fix for this. This fix works for singleplayer and multiplayer and so far has been compatible with other things like Optifine or a minimap mod.

Decompile Minecraft then go to net.minecraft.block.BlockDoublePlant.java. Open with Notepad++ or your other favorite code editing software. Replace lines 123-131 with this:

public IIcon getIcon(int p_149691_1_, int p_149691_2_)
{
int meta=p_149691_2_ & 7;//XP4L
return func_149887_c(p_149691_2_) || meta>=field_149893_M.length ? this.field_149893_M[0] : this.field_149893_M[meta];//XP4L
}

public IIcon func_149888_a(boolean p_149888_1_, int p_149888_2_)
{
return p_149888_1_ ? (p_149888_2_<field_149894_N.length?this.field_149894_N[p_149888_2_]:this.field_149894_N[0]) : (p_149888_2_<field_149893_M.length?this.field_149893_M[p_149888_2_]:this.field_149893_M[0]);//XP4L
}

Recompile and reobfuscate Minecraft and you should get an aja.class file. Copy a clean version of the version you're running and the .json file that goes with and put it in a new folder under versions. I copied my 1.7.2 version into a folder called 1.7.2_Fix. Rename the .jar you copied to the same name you named the folder. Rename the .json file the same thing as well. Open the .json file with Notepad++ or other code editing software and replace whatever is after "id": with the name you used to rename the folder and files. So for me it would look like a 1.7.2_Fix folder inside versions, and inside that I have 2 files named 1.7.2_Fix.jar and 1.7.2_Fix.json, and inside the .json file I changed "1.7.2" to "1.7.2_Fix." Now open the .jar with WinRAR or 7Zip and drop the aja.class file into the .jar and delete META-INF (like installing a mod). Open the launcher then make a new profile using that new version of minecraft you just made. To test and see if it worked, load a singleplayer world and spawn in the buggy flower with your favorite command (ex. /give Codered999 175 1 6). It should no longer crash you if you hold or place the flower.

I found in multiplayer servers it's a huge issue. Griefers can crash players and force them to not be able to join the server unless their player data was erased. If a player observes another player holding the bugged flower WITHOUT the fix, they see a lot of weird changing entities in the other player's hand and sometimes their name too, and then they crash if that flower is placed. Before I fixed it, I saw things like my friend holding a creeper or a squid or a villager with his name above it tiny. In the pictures below you can see that viewing another player holding the flower without the fix causes entities in the background to glitch around. Now with the fix, anyone views the item and placed block as a sunflower stalk without the sunflower head.

Here are some pictures of the bugged flower with and without the fix for anyone interested.

View from another player WITHOUT the fix: http://i.imgur.com/gfP9ozI.png

Another view from another player WITHOUT the fix: http://i.imgur.com/2xKAojw.png

1st person view of item WITH fix: http://i.imgur.com/27Xuuu7.png

3rd person view of item WITH fix: http://i.imgur.com/oXo7NSb.png

1st person view of placed flower WITH fix: http://i.imgur.com/HmRCC2K.png

and another 1st person view of placed flower WITH fix: http://i.imgur.com/HikHQCy.png

Still in 08a and 10c

Wait this bug is still around? I thought adding the purple and black checkered block as the default for all missing textures fixed this?

EDIT: Add 1.78 to the list of versions this bug crashes. The actual relevant line in the code is "java.lang.ArrayIndexOutOfBoundsException: 6". 6 was the data value I used for block 175. There's only plants for 0-5 and 8-13 (the top halves of the plants in 0-5). Yes of course I was smart enough to do this to a brand new world. I was expecting it to die.

Add snapshot 14w18a

Aidan wick, just a quick question, what is that pig thing in the images you posted?

Confirmed for 14w21b

/give @p minecraft:double_plant 1 12
/give @p minecraft:sand 1 3
still cause client crash and make you unable to get into the world.

It would be really nice if this were fixed in 1.8 then Id be able to re open my world. ( I spent a nice amount of time on it and Id like to be able to continue)