daemon/logger/gcplogs: remove ensureHomeIfIAmStatic workaround

This function was added in b86e3bee5aea8e72b7f08e104ebb5d6cb18f8890 to
work around an issue in os/user.Current(), which SEGFAULTS when compiling
statically with cgo enabled (see golang/go#13470).

We hit similar issues in other parts, and contributed a "osusergo" build-
tag in https://go-review.googlesource.com/c/go/+/330753. The "osusergo"
build tag must be set when compiling static binaries with cgo enabled.
If that build-tag is set, the cgo implementation for user.Current() won't
be used, and a pure-go implementation is used instead;
https://github.com/golang/go/blob/go1.19.4/src/os/user/cgo_lookup_unix.go#L5

With the above in place, we no longer need this workaround, and can remove
the ensureHomeIfIAmStatic() function.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

daemon/logger/gcplogs/gcplogging.go

@@ -117,15 +117,6 @@ func New(info logger.Info) (logger.Logger, error) {
 		return nil, fmt.Errorf("No project was specified and couldn't read project from the metadata server. Please specify a project")
 	}
 
-	// Issue #29344: gcplogs segfaults (static binary)
-	// If HOME is not set, logging.NewClient() will call os/user.Current() via oauth2/google.
-	// However, in static binary, os/user.Current() leads to segfault due to a glibc issue that won't be fixed
-	// in a short term. (golang/go#13470, https://sourceware.org/bugzilla/show_bug.cgi?id=19341)
-	// So we forcibly set HOME so as to avoid call to os/user/Current()
-	if err := ensureHomeIfIAmStatic(); err != nil {
-		return nil, err
-	}
-
 	c, err := logging.NewClient(context.Background(), project)
 	if err != nil {
 		return nil, err

daemon/logger/gcplogs/gcplogging_linux.go

@@ -1,27 +0,0 @@
-package gcplogs // import "github.com/docker/docker/daemon/logger/gcplogs"
-
-import (
-	"os"
-
-	"github.com/docker/docker/dockerversion"
-	"github.com/docker/docker/pkg/homedir"
-	"github.com/sirupsen/logrus"
-)
-
-// ensureHomeIfIAmStatic ensure $HOME to be set if dockerversion.IAmStatic is "true".
-// See issue #29344: gcplogs segfaults (static binary)
-// If HOME is not set, logging.NewClient() will call os/user.Current() via oauth2/google.
-// If compiling statically, make sure osusergo build tag is also used to prevent a segfault
-// due to a glibc issue that won't be fixed in a short term
-// (see golang/go#13470, https://sourceware.org/bugzilla/show_bug.cgi?id=19341).
-// So we forcibly set HOME so as to avoid call to os/user/Current()
-func ensureHomeIfIAmStatic() error {
-	// Note: dockerversion.IAmStatic is only available for linux.
-	// So we need to use them in this gcplogging_linux.go rather than in gcplogging.go
-	if dockerversion.IAmStatic == "true" && os.Getenv("HOME") == "" {
-		home := homedir.Get()
-		logrus.Warnf("gcplogs requires HOME to be set for static daemon binary. Forcibly setting HOME to %s.", home)
-		os.Setenv("HOME", home)
-	}
-	return nil
-}

daemon/logger/gcplogs/gcplogging_others.go

@@ -1,8 +0,0 @@
-//go:build !linux
-// +build !linux
-
-package gcplogs // import "github.com/docker/docker/daemon/logger/gcplogs"
-
-func ensureHomeIfIAmStatic() error {
-	return nil
-}