[LU-15928] pass key length as part of index API

• Status: Open
• Project: Lustre
• Affects Version/s: Lustre 2.15.0
• Type: Bug
• Priority: Minor
• Reporter: Andreas Dilger
• Assignee: Sebastien Buisson
• Resolution: Unresolved
• Severity: 3

Description

With fscrypt passing binary names to the underlying ldiskfs storage, the lookup API should be passing the length of the key through the DT index API instead of calling strlen() on the string, otherwise this may incorrectly process keys with embedded NUL bytes.

Issue Links

• is related to: LU-13717 Client-side encryption - support file...

Comments

[Gerrit Updater]

"Andreas Dilger <[e-mail]>" uploaded a new patch: https://review.whamcloud.com/47624
Subject: LU-15928 osd: pass keylen for dt index operations
Project: fs/lustre-release
Branch: master
Current Patch Set: 1
Commit: f88b3fb915f3f0a56da562885db38a8f515260a3

[Andreas Dilger]

Sebastien, I started on this patch but haven't had time to finish it off. I think this is needed to handle binary names properly.

[Sebastien Buisson]

Actually, in order to avoid this large change in the DT index API as part of the LU-13717 series, I had decided to critical encode the names of encrypted files passed from client to server. This escapes NULL, LF, CR, /, DEL and = characters, so that using strlen is safe.

So the code is sane as it is today. But passing the length of the key through the DT index API instead of calling strlen on the string seems to be a better longer term option. And that would avoid the need to critical encode names on client side before the request is sent, just to critical decode those names on server side upon request receive. Unless the ptlrpc layer requires buffers put in the requests to be nul terminated?