Toolbox: /usr/bin/toolbox linked against glibc-2.32 doesn't run on older glibc

DEBU Entry point of container fedora-toolbox-32 is toolbox (PID=0)
Error: invalid entry point PID of container fedora-toolbox-32

This looks like the container failed to start.

Once you have attempted to enter and it failed, could you please try this command and post the logs from it:

$ podman start --attach fedora-toolbox-32

I did and this is the error message:

[vagrant@ci-node-33 ~]$ podman start --attach fedora-toolbox-32
toolbox: /lib64/libc.so.6: version `GLIBC_2.32' not found (required by toolbox)

Here is with the debug output:

[vagrant@ci-node-33 ~]$ podman --log-level debug start --attach fedora-toolbox-32
INFO[0000] podman filtering at log level debug          
DEBU[0000] Called start.PersistentPreRunE(podman --log-level debug start --attach fedora-toolbox-32) 
DEBU[0000] Ignoring libpod.conf EventsLogger setting "/home/vagrant/.config/containers/containers.conf". Use "journald" if you want to change this setting and remove libpod.conf files. 
DEBU[0000] Reading configuration file "/usr/share/containers/containers.conf" 
DEBU[0000] Merged system config "/usr/share/containers/containers.conf": &{Containers:{Devices:[] Volumes:[] ApparmorProfile:containers-default-0.18.0 Annotations:[] CgroupNS:private Cgroups:enabled DefaultCapabilities:[CAP_AUDIT_WRITE CAP_CHOWN CAP_DAC_OVERRIDE CAP_FOWNER CAP_FSETID CAP_KILL CAP_MKNOD CAP_NET_BIND_SERVICE CAP_NET_RAW CAP_SETFCAP CAP_SETGID CAP_SETPCAP CAP_SETUID CAP_SYS_CHROOT] DefaultSysctls:[] DefaultUlimits:[] DefaultMountsFile: DNSServers:[] DNSOptions:[] DNSSearches:[] EnableLabeling:true Env:[PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin] EnvHost:false HTTPProxy:false Init:false InitPath: IPCNS:private LogDriver:k8s-file LogSizeMax:-1 NetNS:slirp4netns NoHosts:false PidsLimit:2048 PidNS:private SeccompProfile:/usr/share/containers/seccomp.json ShmSize:65536k TZ: Umask:0022 UTSNS:private UserNS:host UserNSSize:65536} Engine:{CgroupCheck:true CgroupManager:systemd ConmonEnvVars:[PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin] ConmonPath:[/usr/libexec/podman/conmon /usr/local/libexec/podman/conmon /usr/local/lib/podman/conmon /usr/bin/conmon /usr/sbin/conmon /usr/local/bin/conmon /usr/local/sbin/conmon /run/current-system/sw/bin/conmon] DetachKeys:ctrl-p,ctrl-q EnablePortReservation:true Env:[] EventsLogFilePath:/run/user/1000/libpod/tmp/events/events.log EventsLogger:file HooksDir:[/usr/share/containers/oci/hooks.d] ImageDefaultTransport:docker:// InfraCommand:/pause InfraImage:k8s.gcr.io/pause:3.2 InitPath:/usr/libexec/podman/catatonit LockType:shm Namespace: NetworkCmdPath: NoPivotRoot:false NumLocks:2048 OCIRuntime:/usr/bin/crun OCIRuntimes:map[crun:[/usr/bin/crun /usr/sbin/crun /usr/local/bin/crun /usr/local/sbin/crun /sbin/crun /bin/crun /run/current-system/sw/bin/crun] kata:[/usr/bin/kata-runtime /usr/sbin/kata-runtime /usr/local/bin/kata-runtime /usr/local/sbin/kata-runtime /sbin/kata-runtime /bin/kata-runtime /usr/bin/kata-qemu /usr/bin/kata-fc] runc:[/usr/bin/runc /usr/sbin/runc /usr/local/bin/runc /usr/local/sbin/runc /sbin/runc /bin/runc /usr/lib/cri-o-runc/sbin/runc /run/current-system/sw/bin/runc]] PullPolicy:missing Remote:false RemoteURI: RemoteIdentity: ActiveService: ServiceDestinations:map[] RuntimePath:[] RuntimeSupportsJSON:[crun runc] RuntimeSupportsNoCgroups:[crun] RuntimeSupportsKVM:[kata kata-runtime kata-qemu kata-fc] SetOptions:{StorageConfigRunRootSet:false StorageConfigGraphRootSet:false StorageConfigGraphDriverNameSet:false StaticDirSet:false VolumePathSet:false TmpDirSet:false} SignaturePolicyPath:/etc/containers/policy.json SDNotify:false StateType:3 StaticDir:/home/vagrant/.local/share/containers/storage/libpod StopTimeout:10 TmpDir:/run/user/1000/libpod/tmp VolumePath:/home/vagrant/.local/share/containers/storage/volumes} Network:{CNIPluginDirs:[/usr/libexec/cni /usr/lib/cni /usr/local/lib/cni /opt/cni/bin] DefaultNetwork:podman NetworkConfigDir:/home/vagrant/.config/cni/net.d}} 
DEBU[0000] Using conmon: "/usr/bin/conmon"              
DEBU[0000] Initializing boltdb state at /home/vagrant/.local/share/containers/storage/libpod/bolt_state.db 
DEBU[0000] Using graph driver overlay                   
DEBU[0000] Using graph root /home/vagrant/.local/share/containers/storage 
DEBU[0000] Using run root /run/user/1000/containers     
DEBU[0000] Using static dir /home/vagrant/.local/share/containers/storage/libpod 
DEBU[0000] Using tmp dir /run/user/1000/libpod/tmp      
DEBU[0000] Using volume path /home/vagrant/.local/share/containers/storage/volumes 
DEBU[0000] Set libpod namespace to ""                   
DEBU[0000] [graphdriver] trying provided driver "overlay" 
DEBU[0000] overlay: mount_program=/usr/bin/fuse-overlayfs 
DEBU[0000] backingFs=xfs, projectQuotaSupported=false, useNativeDiff=false, usingMetacopy=false 
DEBU[0000] Initializing event backend file              
DEBU[0000] using runtime "/usr/bin/runc"                
DEBU[0000] using runtime "/usr/bin/crun"                
WARN[0000] Error initializing configured OCI runtime kata: no valid executable found for OCI runtime kata: invalid argument 
DEBU[0000] using runtime "/usr/bin/crun"                
INFO[0000] Setting parallel job count to 7              
DEBU[0000] overlay: mount_data=lowerdir=/home/vagrant/.local/share/containers/storage/overlay/l/55ZKQ2LAMO7JLCJ4FVOE6E6TBG:/home/vagrant/.local/share/containers/storage/overlay/l/2SIOJSIO6LJDSZJHEL6FUA34V2,upperdir=/home/vagrant/.local/share/containers/storage/overlay/3109f3facec37f0bec076d921731107d23a36c918a3eb24bb03685f10179801f/diff,workdir=/home/vagrant/.local/share/containers/storage/overlay/3109f3facec37f0bec076d921731107d23a36c918a3eb24bb03685f10179801f/work,context="system_u:object_r:container_file_t:s0:c14,c464" 
DEBU[0000] mounted container "e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e" at "/home/vagrant/.local/share/containers/storage/overlay/3109f3facec37f0bec076d921731107d23a36c918a3eb24bb03685f10179801f/merged" 
DEBU[0000] Created root filesystem for container e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e at /home/vagrant/.local/share/containers/storage/overlay/3109f3facec37f0bec076d921731107d23a36c918a3eb24bb03685f10179801f/merged 
DEBU[0000] /etc/system-fips does not exist on host, not mounting FIPS mode secret 
DEBU[0000] Setting CGroups for container e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e to user.slice:libpod:e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e 
DEBU[0000] set root propagation to "rslave"             
DEBU[0000] reading hooks from /usr/share/containers/oci/hooks.d 
DEBU[0000] Created OCI spec for container e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e at /home/vagrant/.local/share/containers/storage/overlay-containers/e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e/userdata/config.json 
DEBU[0000] /usr/bin/conmon messages will be logged to syslog 
DEBU[0000] running conmon: /usr/bin/conmon               args="[--api-version 1 -c e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e -u e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e -r /usr/bin/crun -b /home/vagrant/.local/share/containers/storage/overlay-containers/e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e/userdata -p /run/user/1000/containers/overlay-containers/e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e/userdata/pidfile -n fedora-toolbox-32 --exit-dir /run/user/1000/libpod/tmp/exits --socket-dir-path /run/user/1000/libpod/tmp/socket -s -l k8s-file:/home/vagrant/.local/share/containers/storage/overlay-containers/e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e/userdata/ctr.log --log-level debug --syslog --conmon-pidfile /run/user/1000/containers/overlay-containers/e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e/userdata/conmon.pid --exit-command /usr/bin/podman --exit-command-arg --root --exit-command-arg /home/vagrant/.local/share/containers/storage --exit-command-arg --runroot --exit-command-arg /run/user/1000/containers --exit-command-arg --log-level --exit-command-arg error --exit-command-arg --cgroup-manager --exit-command-arg systemd --exit-command-arg --tmpdir --exit-command-arg /run/user/1000/libpod/tmp --exit-command-arg --runtime --exit-command-arg /usr/bin/crun --exit-command-arg --storage-driver --exit-command-arg overlay --exit-command-arg --storage-opt --exit-command-arg overlay.mount_program=/usr/bin/fuse-overlayfs --exit-command-arg --events-backend --exit-command-arg file --exit-command-arg container --exit-command-arg cleanup --exit-command-arg e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e]"
INFO[0000] Running conmon under slice user.slice and unitName libpod-conmon-e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e.scope 
[conmon:d]: failed to write to /proc/self/oom_score_adj: Permission denied

DEBU[0000] Received: 1684                               
INFO[0000] Got Conmon PID as 1681                       
DEBU[0000] Created container e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e in OCI runtime 
DEBU[0000] Attaching to container e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e 
DEBU[0000] connecting to socket /run/user/1000/libpod/tmp/socket/e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e/attach 
DEBU[0000] Starting container e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e with command [toolbox --verbose init-container --home /home/vagrant --monitor-host --shell /bin/bash --uid 1000 --user vagrant] 
DEBU[0000] Started container e54f97de47f50f5ffc98d514629170dce4decd308861aee4e6bccc017abfd24e 
DEBU[0000] Enabling signal proxying                     
toolbox: /lib64/libc.so.6: version `GLIBC_2.32' not found (required by toolbox)
DEBU[0000] Called start.PersistentPostRunE(podman --log-level debug start --attach fedora-toolbox-32) 

Yep, this is not good. Basically some library pulled in by the Toolbox code uses C code requiring the use of cgo. When cgo is used during the build and a libc library is found on the system, the binary is dynamically linked to the libc library. This is normally ok but since Toolbox is used as the entry-point of containers, different versions of libc (resp. glibc) can break it. I have a proposal for a fix (#531) but I need to discuss it more with @debarshiray.

Yes, as @HarryMichal mentioned, this is the problematic part:

[vagrant@ci-node-33 ~]$ podman start --attach fedora-toolbox-32
toolbox: /lib64/libc.so.6: version `GLIBC_2.32' not found (required by toolbox)

It means that a /usr/bin/toolbox binary linked against glibc-2.32 from Fedora 33 on the host, doesn't work with an older glibc from older Fedora releases inside the container.

We end up in this situation because we bind mount /usr/bin/toolbox from the host into the container so that it can be used as the container's entry-point. This worked fine in the past when Toolbox was implemented in POSIX shell, and it would be picked up the environment's /bin/sh. However, it doesn't work so well when it's an ELF binary.

I grabbed the Fedora 33 binary, unpacked it and poked at it a bit.

$ rpm2cpio ./toolbox-0.0.93-2.fc33.x86_64.rpm | cpio -idmv
...
...
$ objdump -T ./usr/bin/toolbox | grep GLIBC_2.32
0000000000000000      DO *UND*  0000000000000000  GLIBC_2.32  pthread_sigmask

Looks like there's a new implementation of pthread_sigmask in glibc-2.32.

I found a way to tell the Go toolchain to avoid the new version of the pthread_sigmask symbol from glibc-2.32. See: https://github.com/containers/toolbox/pull/534

Testing welcome.

Closing.

Please feel free to leave a comment on the PRs or here if you think that it's still broken.

Thanks for the testing, by the way. Much appreciated!