1359938 - Socket status events and tcp fast open

Status: RESOLVED FIXED

(Core :: Networking: HTTP, defect)

Description

[Dragana Damjanovic [:dragana]]

During TFO we buffer data in TCPFastOpenLayer before we call sendto. This is needed because we can only call sendto once and we need to have all data that we want to send in one buffer.


This breaks timing of socket status events.

When we call PR_Write during TFO we do not send data so we should not send NS_NET_STATUS_SENDING_TO event either. The data will be send when we call TCPFastOpenFinish or after the socket is connected.

When socket is connected we need to send the rest of buffered data before we call OnSocketReady, because OnSocketReady can trigger NS_NET_STATUS_WAITING_FOR event.

We need to move call of nsHttpTransaction::SetRequestStart from nsHttpTransaction::ReadRequestSegment because this can be called during TFO as well.

Comment 1

[Dragana Damjanovic [:dragana]]

Attachment: bug_tfo_and_socket_status_event.patch

Comment 2

[Dragana Damjanovic [:dragana]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=c93401ac878dd1faece1748375e8d8698321477f

Comment 3

[Patrick McManus [:mcmanus]]

thanks for including the try report unfortunately its lit up all orange with

Assertion failure: false, at /home/worker/workspace/build/src/security/manager/ssl/nsNSSIOLayer.cpp:1181

so I'll drop the review for now..

Comment 4

[Dragana Damjanovic [:dragana]]

Attachment: bug_tfo_and_socket_status_event.patch

Comment 5

[Dragana Damjanovic [:dragana]]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=21105e0581d4e7c5f0775972e85446414fa7a3cc

Comment 6

[Dragana Damjanovic [:dragana]]

Comment on attachment 8862193 [details] [diff] [review]
bug_tfo_and_socket_status_event.patch

I am dropping review flags.

The problem is not 1359847. I do not know what it is. I am investigating. (I cannot reproduce it locally so it is fun to debug.)

Comment 7

[Dragana Damjanovic [:dragana]]

The problem is bug 1340854. If we do PR_Write with 0 bytes to be written assertions can be hit. I will check if we can call PR_Write(nullptr,0,...) or we are not allowed anymore. I assume that is a regression from bug 1340854. If nss wants it that way I will change my patch.

Comment 8

[Dragana Damjanovic [:dragana]]

So this try failure are a regression from bug 1340854. This is not a really important regression, just a minor thing.

But from ekr's comment, we can not call PR_Write because this will not always call send or recv on a layer under NSS. And we can end up in a deadlock :) - NSS think it has sent data and does not want to call send/recv, but that data sits in a buffer in the layer below.

I will update the patch to call TCPFAstOpenLayer:Send directly not utilizing PR_Write.

Comment 9

[Dragana Damjanovic [:dragana]]

Attachment: bug_tfo_and_socket_status_event.patch

https://treeherder.mozilla.org/#/jobs?repo=try&revision=29c6e4d15948b8a2269b32898681c22583018f03

Comment 10

[Patrick McManus [:mcmanus]]

Comment on attachment 8862619 [details] [diff] [review]
bug_tfo_and_socket_status_event.patch

Review of attachment 8862619 [details] [diff] [review]:
-----------------------------------------------------------------

::: netwerk/base/TCPFastOpenLayer.cpp
@@ +64,5 @@
>      CONNECTED,
>      WAITING_FOR_CONNECTCONTINUE,
>      COLLECT_DATA_FOR_FIRST_PACKET,
> +    WAITING_FOR_CONNECT,
> +    SOCKET_ERROR_STATE

i like this

Comment 11

[Dragana Damjanovic [:dragana]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/4a3896a7e29f605d0bc509ca98095c1960aa70cf
Bug 1359938 - Fix socket status events for TCP Fast Open. r=mcmanus

Comment 12

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/4a3896a7e29f
Fix socket status events for TCP Fast Open. r=mcmanus

Comment 13

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/4a3896a7e29f