1630439 - Issue opening url with underscore at the end on Android

Status: RESOLVED INVALID

(Core :: Networking: DNS, defect, P3)

Description

[Tim Langhorst]

Attachment: Screenshot_20200416-002954.jpg

When I try to open an URL with an underscore (for example https://cromefire_.gitlab.io/nativeshell-api-definition) it immediately returns "Address Not Found" (it doesn't seem to make a network request at all).

This affects both nightly and stable, but it works fine on desktop.

Comment 1

[Tim Langhorst]

Attachment: Screenshot_20200416-004333.jpg

Comment 2

[Stefan Arentz | :st3fan | ⏰ EST | he/him]

I moved this to Core / Networking: DNS because I am not sure what to do with this or whether this should work.

Comment 3

[Valentin Gosu [:valentin] (he/him)]

So, _ in a hostname isn't really common, but we allow it nonetheless.
For some reason it seems the android implementation of getaddrinfo doesn't.
When I switched to using TRR, the URL in comment 0 worked with no problem.
I also tried a custom C++ program that calls getaddrinfo, and had the same issue.
I'm not sure how Chrome is working. Maybe they're using a custom resolver?

Comment 4

[Tim Langhorst]

So should this be reported to Android?

Comment 5

[Valentin Gosu [:valentin] (he/him)]

(In reply to Tim Langhorst from comment #4)

So should this be reported to Android?

Likely yes.

Comment 6

[Tim Langhorst]

If you can provide me with details which function is affected and maybe a small "reproduction" I can report it there

Comment 7

[Valentin Gosu [:valentin] (he/him)]

Attachment: dns_test.c

I ran this test on Linux (it works) and on Android in the CxxDroid App where it didn't.

Comment 8

[Valentin Gosu [:valentin] (he/him)]

It would be nice to find a fix for this, but it's not clear what that would be.
Seems like a getaddrinfo bug. Looking at Chrome's code it would seem they use the same, not sure what their trick is to make this work.

Comment 9

[Valentin Gosu [:valentin] (he/him)]

(In reply to Valentin Gosu [:valentin] (he/him) from comment #8)

Seems like a getaddrinfo bug. Looking at Chrome's code it would seem they use the same, not sure what their trick is to make this work.

Once I disabled the Async DNS feature in Chrome it stopped working too.
https://discourse.pi-hole.net/t/disable-async-dns-resolver-in-google-chrome/9500

Definitely an Android bug. Closing since there's nothing we can do here.
It is mitigated by using TRR (although we have no UI for it on Android).

Comment 10

[Tim Langhorst]

How can I enable TRR?

Comment 11

[Valentin Gosu [:valentin] (he/him)]

(In reply to Tim Langhorst from comment #10)

How can I enable TRR?

Go to about:config and set network.trr.mode to 2
More info here and here

Comment 12

[Tim Langhorst]

The issue already existed in a similar fashion I added the repro snippet: https://issuetracker.google.com/issues/154694663