Composer hangs when cloning SSH repository with enabled ControlMaster

[astehlik]

This is a really strange bug.

I'm using the ControlMaster setting of SSH to speed up connections to our Git server:

Host mygitserver
    ControlMaster auto
    ControlPath ~/.ssh/master-%r@%h:%p
    ControlPersist 1h

I can manually access the Server with SSH and clone repositories without a problem.

But when I use composer and the master file does not exist, composer just stops working on this command:

git clone --no-checkout 'git@mygitserver:mydir/myrepo.git' '/the/target/dir' && cd '/the/target/dir' && git remote add composer 'git@mygitserver:mydir/myrepo.git' && git fetch composer

When I look at the process tree, I see this:

php /usr/local/bin/composer.phar -vvv update
  \_ [sh] <defunct>

When I open a connection to the SSH server before running composer and the master file already exists the composer command runs without problems.

[cs278]

Eureka, I've been having this problem for ages never occurred to me it might be down to SSH connection multiplexing. This would explain why I don't see it very often and a SIGINT and re run always works.

[astehlik]

I'm glad I'm not the only one ;)

As a workaround I'm using a script that does a ssh -t mygitserver before the composer run.

[sbuzonas]

This has been a bug in SSH for a while with control persist.

https://bugzilla.mindrot.org/show_bug.cgi?id=1988

[astehlik]

Thanks for the pointer.

Since this does not seem to be a composer bug, maybe this should be added to the troubleshooting section in the docs?

[alcohol]

Odd, I use roughly the same settings but I have never had any trouble with it.

Host *
    TCPKeepAlive no
    ServerAliveInterval 10
    ServerAliveCountMax 3
    ControlMaster auto
    ControlPath ~/.ssh/ssh-%r@%h:%p
    ControlPersist 2h

[staabm]

@alcohol maybe you dont use a ssh version which is affected by the bug (see bugreport)

[alcohol]

On my server

rob@robbast ~ (master) $ ssh -V
OpenSSH_6.8p1, OpenSSL 1.0.2c 12 Jun 2015

On my macbook

rob@emac019 ~ (master) $ ssh -V
OpenSSH_6.2p2, OSSLShim 0.9.8r 8 Dec 2011

Yay for homebrew

rob@emac019 ~ (master) $ ssh -V
OpenSSH_6.8p1, OpenSSL 1.0.2c 12 Jun 2015

[cs278]

By the sounds of things it was never fixed in SSH they just added the -E option so you could stop it opening stderr. So I suspect unless that option is being used it should be present in all versions that support multiplexing.

@alcohol I'm using 6.6 and can reproduce the problem, the difference is I use a time out of 10 minutes rather than your much longer 2 hours. I think I'll bump mine up for GitHub.

Console output on my machine: https://gist.github.com/cs278/7e60c231159bc2249cd8

Steps to reproduce are basically:

cd "$(mktemp -d)"
ssh -O exit git@github.com
composer require --prefer-source psr/log '*'

[alcohol]

Eh your steps to reproduce doesn't really work for me...

rob@emac019 ~/Music (master) $ cd "$(mktemp -d)"
rob@emac019 /var/folders/q2/s6l2p2gj36l710r752smh96c0000gp/T/tmp.4dok4Aw4Dv $ ssh -O exit git@github.com
Control socket connect(/Users/rob/.ssh/ssh-git@github.com:22): No such file or directory
rob@emac019 /var/folders/q2/s6l2p2gj36l710r752smh96c0000gp/T/tmp.4dok4Aw4Dv $ composer require --prefer-source psr/log '*'
./composer.json has been created
Loading composer repositories with package information
Updating dependencies (including require-dev)
  - Installing psr/log (1.0.0)
    Cloning fe0936ee26643249e916849d48e3a51d5f5e278b

Writing lock file
Generating autoload files

Edit: never mind, had to add a github.com entry to my .ssh config;

Host github.com
    User git
    IdentityFile ~/.ssh/id_rsa

rob@emac019 ~ (master) $ cd "$(mktemp -d)"
rob@emac019 /var/folders/q2/s6l2p2gj36l710r752smh96c0000gp/T/tmp.kSrT2CsKd6 $ ssh -O exit git@github.com
Exit request sent.
rob@emac019 /var/folders/q2/s6l2p2gj36l710r752smh96c0000gp/T/tmp.kSrT2CsKd6 $ composer require --prefer-source psr/log '*'
./composer.json has been created
Loading composer repositories with package information
Updating dependencies (including require-dev)
  - Installing psr/log (1.0.0)
    Cloning fe0936ee26643249e916849d48e3a51d5f5e278b

Writing lock file
Generating autoload files

[stof]

@alcohol you should also force composer to use the ssh url when cloning the repo. If it clones over https, it will of course not be impacted. and by default, SSH is the last protocol: https://getcomposer.org/doc/06-config.md#github-protocols and

composer/src/Composer/Config.php

Line 30 in 8466129

'github-protocols' => array('git', 'https', 'ssh'),

[alcohol]

I see. So I guess his internal server doesn't support the git and https protocol, hence the ssh fallback.

[sbuzonas]

I have the issue with private repos. I have my environment set up to point GIT_SSH to a wrapper that spawns a control master if the socket isn't available. Then calls ssh.

[Seldaek]

Closing as it's not clear what we can do to help.