scp regression on 6.0.0-rc.1

[webvictim]

Description

What happened:

# build/teleport is a binary
$ ls -l build/teleport
-rwxr-xr-x. 1 gus gus 70682783 Feb 24 17:23 build/teleport

# try to scp it to hades (node running 6.0.0-rc.1), it fails with this weird error
$ scp build/teleport hades:~/tmp
ERROR:
	open home/gus/tmp: no such file or directory

lost connection

# try to scp it to zeus (5.1.2) with the same command, works
$ scp build/teleport zeus:~/tmp
teleport                                                                                                                    100%   67MB  14.6MB/s   00:04

# file was created as expected
$ ssh zeus -- ls -l tmp
-rwxr-xr-x 1 gus gus 70682783 Feb 24 17:29 tmp

# same happens with `tsh scp` to hades, same error in the teleport logs
$ tsh scp build/teleport hades:~/tmp
-> build/teleport (70682783)
error: Process exited with status 1

# tsh scp works to zeus
$ tsh scp build/teleport zeus:~/tmp
-> build/teleport (70682783)

Not sure why the home/gus/tmp is missing the preceding / in the error.

Teleport logs from hades:

Feb 24 17:32:25 hades teleport[1830443]: DEBU [NODE]      Handling request exec, want reply true. id:13 local:192.168.64.201:55646 login:gus remote:192.168.64.1:57146 teleportUser:webvictim regular/sshserver.go:1269
Feb 24 17:32:25 hades teleport[1830443]: INFO [NODE]      Creating (exec) session ff83677f-df42-4cf0-87cf-7fb8b9654f61. id:13 local:192.168.64.201:55646 login:gus remote:192.168.64.1:57146 teleportUser:webvictim srv/sess.go:234
Feb 24 17:32:25 hades teleport[1830443]: DEBU [SESSION:N] Using async streamer for session ff83677f-df42-4cf0-87cf-7fb8b9654f61. srv/sess.go:1043
Feb 24 17:32:25 hades teleport[1830443]: INFO [AUDIT]     session.start addr.remote:192.168.64.1:57146 cluster_name:teleport.example.com code:T2000I ei:0 event:session.start login:gus namespace:default server_addr:192.168.64.201:55646 server_hostname:hades server_id:0065053d-e8e9-4880-aebb-e2d9499b681e server_labels:map[arch:x86_64 external_ipv4:142.167.142.235 external_ipv6:No IPv6 hostname:hades running_containers:alertmanager caddy cadvisor delugevpn grafana homebridge jackett lidarr nodeexporter nodered ombi plex plexpy prometheus pushgateway radarr sensorexporter smokeping sonarr watchtower stopped_containers: teleport_version:Teleport v6.0.0-rc.1 git:v6.0.0-rc.1-0-g5470bb912 go1.15.5 type:node] sid:ff83677f-df42-4cf0-87cf-7fb8b9654f61 time:2021-02-24T21:32:25.464Z uid:5435bd13-0028-41d8-83fa-cdca81ab9c32 user:webvictim events/emitter.go:317
Feb 24 17:32:25 hades teleport[1830443]: INFO [NODE]      Started local command execution: "/usr/local/bin/teleport scp --remote-addr=192.168.64.1:57146 --local-addr=192.168.64.201:55646 -t ~/tmp" id:13 local:192.168.64.201:55646 login:gus remote:192.168.64.1:57146 teleportUser:webvictim srv/exec.go:182
Feb 24 17:32:25 hades teleport[1830443]: INFO [SESSION:N] Closing session ff83677f-df42-4cf0-87cf-7fb8b9654f61. srv/sess.go:632
Feb 24 17:32:25 hades teleport[1830443]: ERROR:
Feb 24 17:32:25 hades teleport[1830443]:         open home/gus/tmp: no such file or directory
Feb 24 17:32:25 hades teleport[1830443]: DEBU [NODE]      Local command failed: exit status 1. id:13 local:192.168.64.201:55646 login:gus remote:192.168.64.1:57146 teleportUser:webvictim srv/exec.go:196
Feb 24 17:32:25 hades teleport[1830443]: DEBU [NODE]      Exec request ("/usr/local/bin/teleport scp --remote-addr=192.168.64.1:57146 --local-addr=192.168.64.201:55646 -t ~/tmp") complete: 1 id:13 local:192.168.64.201:55646 login:gus remote:192.168.64.1:57146 teleportUser:webvictim regular/sshserver.go:1249
Feb 24 17:32:25 hades teleport[1830443]: INFO [AUDIT]     scp action:upload addr.local:192.168.64.201:55646 addr.remote:192.168.64.1:57146 cluster_name:teleport.example.com code:T3005E command:/usr/local/bin/teleport scp --remote-addr=192.168.64.1:57146 --local-addr=192.168.64.201:55646 -t ~/tmp ei:0 event:scp exitCode:1 exitError:exit status 1 login:gus namespace:default path:~/tmp server_id:0065053d-e8e9-4880-aebb-e2d9499b681e sid:ff83677f-df42-4cf0-87cf-7fb8b9654f61 time:2021-02-24T21:32:25.556Z uid:68fb14f6-5b5a-4915-8e32-9aac0abe8853 user:webvictim events/emitter.go:317
Feb 24 17:32:25 hades teleport[1830443]: DEBU [SSH:NODE]  Closed connection 192.168.64.1:57146. sshutils/server.go:448
Feb 24 17:32:25 hades teleport[1830443]: INFO [AUDIT]     session.data addr.remote:192.168.64.1:57146 cluster_name: code:T2006I ei:2.147483646e+09 event:session.data login:gus namespace:default rx:3822 server_id:0065053d-e8e9-4880-aebb-e2d9499b681e sid:ff83677f-df42-4cf0-87cf-7fb8b9654f61 time:2021-02-24T21:32:25.56Z tx:5463 uid:32822ba3-8323-4aec-a2ab-22911882acec user:webvictim events/emitter.go:317

Also note weird line break in the error message.

What you expected to happen: scp to hades should work just as it does to zeus.

Reproduction Steps

See above.

Here's my ~/.ssh/config if it helps:

Host teleport.example.com
    User gus
    Port 3023
    IdentityFile ~/.tsh/keys/teleport.example.com/webvictim
    UserKnownHostsFile ~/.ssh/teleport/known_hosts

Host hades
    User gus
    ProxyCommand sh -c '~/.ssh/teleport/login.sh teleport.example.com webvictim && ssh teleport.example.com -s proxy:%h:%p'
    Port 3022
    IdentityFile ~/.tsh/keys/teleport.example.com/webvictim
    HostKeyAlias hades.teleport.example.com
    UserKnownHostsFile ~/.ssh/teleport/known_hosts

Host zeus
    User gus
    ProxyCommand sh -c '~/.ssh/teleport/login.sh teleport.example.com webvictim && ssh teleport.example.com -s proxy:%h:%p'
    Port 3022
    IdentityFile ~/.tsh/keys/teleport.example.com/webvictim
    HostKeyAlias zeus.teleport.example.com
    UserKnownHostsFile ~/.ssh/teleport/known_hosts

(there are more details about the exact setup at

Server Details

• Teleport version (run teleport version):

$ ssh hades -- teleport version
Teleport v6.0.0-rc.1 git:v6.0.0-rc.1-0-g5470bb912 go1.15.5

$ ssh zeus -- teleport version
Teleport v5.1.2 git:v5.1.2-0-g822d10b44 go1.15.5

• tsh version: Teleport v5.1.2 git:v5.1.2-0-g822d10b44 go1.15.5
• Server OS (e.g. from /etc/os-release): Fedora 32
• Where are you running Teleport? (e.g. AWS, GCP, Dedicated Hardware): Home lab