Fresh install unable to install anything

[sirideain]

Here is what I see with verbose. I get this trying to install clippy or rustfmt. I assume I would get it with other crates.

Updating registry https://github.com/rust-lang/crates.io-index
error: [20/-1] Cannot checkout to invalid path '3/n/nul'

[ncoish]

I get the same failure when using cargo build or cargo update --verbose:

cargo update --verbose
Updating registry https://github.com/rust-lang/crates.io-index
error: failed to load source for a dependency on num

Caused by:
Unable to update registry https://github.com/rust-lang/crates.io-index

Caused by:
[20/-1] Cannot checkout to invalid path '3/n/nul'

Platform: Windows 10
cargo 0.19.0-nightly (fa7584c 2017-04-26)

[azriel91]

Yay. NUL is a reserved name.

Other names to avoid / handle:

Do not use the following reserved names for the name of a file:
CON, PRN, AUX, NUL, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, and LPT9:

source: https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx

[withoutboats]

ping @alexcrichton @carols10cents not sure who else

We probably need to delete this crate and add all of these windows reserved names to the list of reserved names in crates.io.

[withoutboats]

Once nul is deleted I have a PR to reserve the names listed in @azriel91's post rust-lang/crates.io#695

[albel727]

@withoutboats Why wait? Make your PR sooner, for it better get some review before someone else has an idea to get famous quickly.

[withoutboats]

@albel727 The PR is open (I linked to it), but I'm not sure what will happen if its deployed before nul is deleted.

[carols10cents]

What will happen is if there are any updates to the nul crate after the deploy, those updates won't work. Which I think is fine. I'd rather prevent more things that cause problems first.

[albel727]

@withoutboats Ah, I thought it would be a PR against cargo itself. Nevermind me.

[carols10cents]

Deploying to production of the crates.io pr starting now.

[Manishearth]

This issue cannot be fixed by blacklisting crate names on crates.

Cargo uses a trie, so you could always trigger the trie to break via things like uploading packages nula, nulb,... so that a nul folder is created in the filesystem trie. We need a crates trie blacklist that makes sure these folder names don't get created in the trie (falling back to storing them flat one level above), as well as blacklists for the existing name.

Unless I'm misunderstanding how the registry trie works.

[carols10cents]

@Manishearth The trie is 2 letters, so a crate named nula would go in nu/la. Idk if that still leaves problematic files

[withoutboats]

All of the Windows names are 3 or 4 characters so it should be fine.

[shepmaster]

Cargo uses a trie, so you could always trigger the trie to break via things like uploading packages nula, nulb,... so that a nul folder is created in the filesystem trie.

If the directory scheme were to be changed, I'd recommend switching to using a hash of the name for the prefix directories; this leads to better distribution of files per directory. Too many things in a directory can have poor performance implications.

[retep998]

If the directory scheme were to be changed, I'd recommend switching to using a hash of the name for the prefix directories; this leads to better distribution of files per directory. Too many things in a directory can have poor performance implications.

With the current system you could trivially create a few million crates with a certain prefix and easily DOS anyone with a filesystem that doesn't handle that many files in a folder.