forgejo/services/task/migrate.go
Mathieu Fenniak f93d2cb261 ci: detect and prevent empty case statements in Go code (#11593)
One of the security patches released 2026-03-09 [fixed a vulnerability](d1c7b04d09) caused by a misapplication of Go `case` statements, where the implementation would have been correct if Go `case` statements automatically fall through to the next case block, but they do not.  This PR adds a semgrep rule which detects any empty `case` statement and raises an error, in order to prevent this coding mistake in the future.

For example, code like this will now trigger a build error:
```go
	switch setting.Protocol {
	case setting.HTTPUnix:
	case setting.FCGI:
	case setting.FCGIUnix:
	default:
		defaultLocalURL := string(setting.Protocol) + "://"
	}
```

Example error:
```
    cmd/web.go
   ❯❯❱ semgrep.config.forgejo-switch-empty-case
          switch has a case block with no content. This is treated as "break" by Go, but developers may
          confuse it for "fallthrough".  To fix this error, disambiguate by using "break" or
          "fallthrough".

          279┆ switch setting.Protocol {
          280┆ case setting.HTTPUnix:
          281┆ case setting.FCGI:
          282┆ case setting.FCGIUnix:
          283┆ default:
          284┆   defaultLocalURL := string(setting.Protocol) + "://"
          285┆   if setting.HTTPAddr == "0.0.0.0" {
          286┆           defaultLocalURL += "localhost"
          287┆   } else {
          288┆           defaultLocalURL += setting.HTTPAddr
```

As described in the error output, this error can be fixed by explicitly listing `break` (the real Go behaviour, to do nothing in the block), or by listing `fallthrough` (if the intent was to fall through).

All existing code triggering this detection has been changed to `break` (or, rarely, irrelevant cases have been removed), which should maintain the same code functionality.  While performing this fixup, a light analysis was performed on each case and they *appeared* correct, but with ~65 cases I haven't gone into extreme depth.

Tests are present for the semgrep rule in `.semgrep/tests/go.go`.

## Checklist

The [contributor guide](https://forgejo.org/docs/next/contributor/) contains information that will be helpful to first time contributors. There also are a few [conditions for merging Pull Requests in Forgejo repositories](https://codeberg.org/forgejo/governance/src/branch/main/PullRequestsAgreement.md). You are also welcome to join the [Forgejo development chatroom](https://matrix.to/#/#forgejo-development:matrix.org).

### Documentation

- [ ] I created a pull request [to the documentation](https://codeberg.org/forgejo/docs) to explain to Forgejo users how to use this change.
- [x] I did not document these changes and I do not expect someone else to do it.

### Release notes

- [ ] This change will be noticed by a Forgejo user or admin (feature, bug fix, performance, etc.). I suggest to include a release note for this change.
- [x] This change is not visible to a Forgejo user or admin (refactor, dependency upgrade, etc.). I think there is no need to add a release note for this change.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/11593
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: Mathieu Fenniak <mathieu@fenniak.net>
Co-committed-by: Mathieu Fenniak <mathieu@fenniak.net>
2026-03-10 02:50:28 +01:00

155 lines
4.8 KiB
Go

// Copyright 2019 Gitea. All rights reserved.
// SPDX-License-Identifier: MIT
package task
import (
"context"
"errors"
"fmt"
"strings"
"time"
admin_model "forgejo.org/models/admin"
"forgejo.org/models/db"
repo_model "forgejo.org/models/repo"
user_model "forgejo.org/models/user"
"forgejo.org/modules/graceful"
"forgejo.org/modules/json"
"forgejo.org/modules/log"
"forgejo.org/modules/migration"
"forgejo.org/modules/process"
"forgejo.org/modules/structs"
"forgejo.org/modules/timeutil"
"forgejo.org/modules/util"
"forgejo.org/services/migrations"
notify_service "forgejo.org/services/notify"
)
func handleCreateError(owner *user_model.User, err error) error {
switch {
case repo_model.IsErrReachLimitOfRepo(err):
return fmt.Errorf("you have already reached your limit of %d repositories", owner.MaxCreationLimit())
case repo_model.IsErrRepoAlreadyExist(err):
return errors.New("the repository name is already used")
case db.IsErrNameReserved(err):
return fmt.Errorf("the repository name '%s' is reserved", err.(db.ErrNameReserved).Name)
case db.IsErrNamePatternNotAllowed(err):
return fmt.Errorf("the pattern '%s' is not allowed in a repository name", err.(db.ErrNamePatternNotAllowed).Pattern)
default:
return err
}
}
func runMigrateTask(ctx context.Context, t *admin_model.Task) (err error) {
defer func(ctx context.Context) {
if e := recover(); e != nil {
err = fmt.Errorf("PANIC whilst trying to do migrate task: %v", e)
log.Critical("PANIC during runMigrateTask[%d] by DoerID[%d] to RepoID[%d] for OwnerID[%d]: %v\nStacktrace: %v", t.ID, t.DoerID, t.RepoID, t.OwnerID, e, log.Stack(2))
}
if err == nil {
err = admin_model.FinishMigrateTask(ctx, t)
if err == nil {
notify_service.MigrateRepository(ctx, t.Doer, t.Owner, t.Repo)
return
}
log.Error("FinishMigrateTask[%d] by DoerID[%d] to RepoID[%d] for OwnerID[%d] failed: %v", t.ID, t.DoerID, t.RepoID, t.OwnerID, err)
}
log.Error("runMigrateTask[%d] by DoerID[%d] to RepoID[%d] for OwnerID[%d] failed: %v", t.ID, t.DoerID, t.RepoID, t.OwnerID, err)
t.EndTime = timeutil.TimeStampNow()
t.Status = structs.TaskStatusFailed
t.Message = err.Error()
if err := t.UpdateCols(ctx, "status", "message", "end_time"); err != nil {
log.Error("Task UpdateCols failed: %v", err)
}
// then, do not delete the repository, otherwise the users won't be able to see the last error
}(graceful.GetManager().ShutdownContext()) // even if the parent ctx is canceled, this defer-function still needs to update the task record in database
if err = t.LoadRepo(ctx); err != nil {
return err
}
// if repository is ready, then just finish the task
if t.Repo.Status == repo_model.RepositoryReady {
return nil
}
if err = t.LoadDoer(ctx); err != nil {
return err
}
if err = t.LoadOwner(ctx); err != nil {
return err
}
var opts *migration.MigrateOptions
opts, err = t.MigrateConfig()
if err != nil {
return err
}
opts.MigrateToRepoID = t.RepoID
pm := process.GetManager()
ctx, cancel, finished := pm.AddContext(graceful.GetManager().ShutdownContext(), fmt.Sprintf("MigrateTask: %s/%s", t.Owner.Name, opts.RepoName))
defer finished()
t.StartTime = timeutil.TimeStampNow()
t.Status = structs.TaskStatusRunning
if err = t.UpdateCols(ctx, "start_time", "status"); err != nil {
return err
}
// check whether the task should be canceled, this goroutine is also managed by process manager
go func() {
for {
select {
case <-time.After(2 * time.Second):
break
case <-ctx.Done():
return
}
task, _ := admin_model.GetMigratingTask(ctx, t.RepoID)
if task != nil && task.Status != structs.TaskStatusRunning {
log.Debug("MigrateTask[%d] by DoerID[%d] to RepoID[%d] for OwnerID[%d] is canceled due to status is not 'running'", t.ID, t.DoerID, t.RepoID, t.OwnerID)
cancel()
return
}
}
}()
t.Repo, err = migrations.MigrateRepository(ctx, t.Doer, t.Owner.Name, *opts, func(format string, args ...any) {
message := admin_model.TranslatableMessage{
Format: format,
Args: args,
}
bs, _ := json.Marshal(message)
t.Message = string(bs)
_ = t.UpdateCols(ctx, "message")
})
if err == nil {
log.Trace("Repository migrated [%d]: %s/%s", t.Repo.ID, t.Owner.Name, t.Repo.Name)
return nil
}
if repo_model.IsErrRepoAlreadyExist(err) {
return errors.New("the repository name is already used")
}
// remoteAddr may contain credentials, so we sanitize it
err = util.SanitizeErrorCredentialURLs(err)
if strings.Contains(err.Error(), "Authentication failed") ||
strings.Contains(err.Error(), "could not read Username") {
return fmt.Errorf("authentication failed: %w", err)
} else if strings.Contains(err.Error(), "fatal:") {
return fmt.Errorf("migration failed: %w", err)
}
// do not be tempted to coalesce this line with the return
err = handleCreateError(t.Owner, err)
return err
}