MediaWiki reports a mime type of application/octet-stream [ application/vnd.microsoft.portable-executable would be better, but current code does octet-stream]

Actual behaviour:

MediaWiki reports unknown/unknown.

MediaWiki has code that looks for both .exe extension and MZ magic numbers. It should be able to detect this (The detection is also used as part of the blacklist, so that presumably isn't working either for these file types)

Details

Related Changes in Gerrit:

	Subject	Repo	Branch	Lines +/-
	Make mime recognizer recognize exe files.	mediawiki/core	master	+26 -10

Customize query in gerrit

Related Objects

Mentioned In: T302395: MediaWiki confused over mime-type of exe files
Mentioned Here: T302395: MediaWiki confused over mime-type of exe files
rMW27105c21295d: * (bug 898) Mime type autodetection.

Event Timeline

Bawolff created this task.Mar 10 2020, 7:34 PM

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DannyS712 subscribed.Mar 10 2020, 7:46 PM

Llanddewi subscribed.Mar 11 2020, 8:16 AM

The answer is because unknown/unknown is set as the canonical alias for application/octet-stream (In buildin mime types but not in mime.types file). That seems wrong.

Its been that way since 27105c21295 so i guess this has always been broken

Change 579881 had a related patch set uploaded (by Brian Wolff; owner: Brian Wolff):
[mediawiki/core@master] Make mime recognizer recognize exe files.

https://gerrit.wikimedia.org/r/579881

gerritbot added a project: Patch-For-Review.Mar 16 2020, 2:58 AM

Llanddewi mentioned this in T302395: MediaWiki confused over mime-type of exe files.Feb 23 2022, 1:13 PM

Krinkle merged a task: T302395: MediaWiki confused over mime-type of exe files.Feb 28 2022, 8:12 PM

Krinkle edited projects, added: MediaWiki-libs-Mime; removed: MediaWiki-Uploading.

Krinkle added subscribers: Krinkle, tstarling.

Restricted Application added a project: Performance-Team. · View Herald TranscriptFeb 28 2022, 8:13 PM

Patches for this are welcome. @Llanddewi I believe you may be interested in this. There is a patch already with code that afaik is in fairly good shape but needs to be rebased and has a failing test. Feel free to rebase it and/or re-create as a new patch.

In T302395#7742674, @Krinkle wrote:
Based on chatting with @tstarling, I think we're fine with owning and maintaining support for detecting EXE files properly in MediaWiki.

The detection logic for its "magic header" binary code already exists but is currently explicitly mapped to octet-stream. I had mistakenly thought it got there by means of a fallback but it is fact explicitly mapped there:
MineAnalyzer.php
'MZ'               => 'application/octet-stream', // DOS/Windows executable
I'm merging this into task T247348, with the understanding that if this correctly recognises it as a distinct type and if that type isn't considered "unknown" that the issue you found is also naturally avoided/resolved.